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Posted by: r_towle Jan 28 2005, 12:49 PM

Has anyone tried to build a flat 8 with two type 4 motors?

Theoretical questions.
Assumptions
2 motors each producing 100 HP and 100 Lb/ft of Torque

The motors are end to end, front to rear.
The cranks are fastened together either bolted or welded.

1) Would you get 200hp and 200 lb/ft or torque? or is there some multiplier...seems like you would produce more torque..

2) could it be done with a single ignition system available for sale off the shelf.

3) could you do it without two distributors? crank fired ignition system..I am thinking that there could be a wheel placed in between the motors to give you something to time from.

4) I am assuming either a nice FI system, or four carbs.

Has anyone done this?
I would like to see some articles or web pages if this has been done in the aircooled world...

Thanx in advance
Rich

Posted by: Mueller Jan 28 2005, 01:03 PM

yep, a few have been done........I know I've posted pictures as a well as a few others....

for a 914 application, the motor wouldn't fit unless you moved the assembly back a few inches...even without the cooling fan, I don't think it would fit in the stock location

for the cost/time/ it would take to make one, there are a dozen better engine choices unless one just wants to do it for the novelty of doing it....

since it's already been done a few times, there is no novelty in it....nothing ground breaking....kinda boring

Posted by: sanman Jan 28 2005, 01:05 PM

I thought of it but I think it would be


too long to fit in a 914 and
you would loose 1 fan for cooling

now on the other hand If some one made a 6 case that took t4 or t1 P/C,rods, and heads it may work
but that just my thoughts

forget it! you would need a 6 crank, and cam
Just get a chevy v8 or a porsche 6 and be done

Posted by: r_towle Jan 28 2005, 01:05 PM

i was hoping you would answer...you always think outside the box...

So what about the torque numbers...is it simply double???

It just seems that is would be multiplied somehow..
and where would i find some pics....
Rich

Posted by: andys Jan 28 2005, 01:08 PM

It's been done both ways. I saw a pic years ago of a specially cast block for 8 cylinders. Also, the Fittipaldi brothers raced a Bug in Brazil where they coupled two motors together similar to what you describe, in a mid-engined configuration. They were apparently very successful with this car. Interesting way that they ducted air to cool the motors: they slanted the windshield back into the driver compatment. Air was ducted over the driver, then down to the two motors.

Andy

Posted by: r_towle Jan 28 2005, 01:14 PM

honestly cooling seems like a simple part of it ...
A custom horizontal system would work.

What are the numbers...in theory???

Rich

Posted by: Cloudbuster Jan 28 2005, 01:22 PM

Double displacement does not usually equal double torque or horsepower. Not sure why.

In WWII, Pratt & Whitney took 2 14 cylinder radials and joined them onto a single case, resulting in a 28 cylinder that made 50% more HP. In the '90s Honda simply upped the size of a 600cc four to 900cc and got 20% more power (50% more displacement). Granted, the stock T4 is restricted, so using a RAT 2270 as a basis, maybe 250 HP would come from a T4x2. Just guessing.

Posted by: nebreitling Jan 28 2005, 01:36 PM

i would think that you could never get double the power. maybe 150%, 175% if lucky.

entropy's a bitch.

Posted by: Jake Raby Jan 28 2005, 01:59 PM

Already have a print in with moldex on the crank.
Already dissected 4 engine cases to find the best mating points.... Just need time

Posted by: synthesisdv Jan 28 2005, 02:19 PM

asked the same question a while back....

here's what I got.


Attached image(s)

Posted by: Cloudbuster Jan 28 2005, 02:23 PM

Hans Dahlbeck? Isn't he the brain donor in 'Young Frankenstein'? Seems fitting.

Posted by: synthesisdv Jan 28 2005, 02:54 PM

QUOTE (Cloudbuster @ Jan 28 2005, 03:23 PM)

Hans Dahlbeck? Isn't he the brain donor in 'Young Frankenstein'? Seems fitting.

No, I think you mean Mr. Abby Normal

Posted by: BigD9146gt Jan 28 2005, 03:33 PM

You'd be better off starting with two early 2.0 911 engines. By cutting the center two cylinders out of one case and placing them in the center of the other case, you add two cyclinders to an already superior design. Having small cylinders to begine with (width wise) helps keep the lenth of the motor down too. Then a Scat crank and some custom cams, you have the better overhead cam design, better cooling, and better head flow. Plus with the early cases, they're all aluminum like the 914 case, making welding them together easier... and stronger.

Posted by: Jake Raby Jan 28 2005, 03:47 PM

Nah.... Can't make a statement with a 911 engine!

Plus, they cost too damn much to play with at this level..

I'm using 964 heads though..

Engine will go in a mid engine 1961 VW Single cab truck, under the bed.....

Posted by: r_towle Jan 28 2005, 05:15 PM

QUOTE (Jake Raby @ Jan 28 2005, 01:47 PM)

Nah.... Can't make a statement with a 911 engine! Plus, they cost too damn much to play with at this level.. I'm using 964 heads though.. Engine will go in a mid engine 1961 VW Single cab truck, under the bed.....

I had a funny feeling you would be looking at this at some point in your life...

I may try to get this done, just to see if it can be done smoothly, easily, and if it has benefit.

I am thinking why not use the heavy strong crank and push rods, lighter cylinders and pistons, and turbocharge the whole thing....
It would be a cool way to use parts that may be inferior for a hopped up T4 motor, but rugged enough for a T8 motor.

Rich

Posted by: Mueller Jan 28 2005, 05:29 PM

QUOTE

I may try to get this done, just to see if it can be done smoothly, easily, and if it has benefit.

if it was even one of those choices above, you'd see more than a few running around

it'll have all of the same problems or issues a /4 has, the only benifit is if you are trying to reach a certain hp level...if stock /4 has 100 and you want 175, then the /8 should be able to give you 175 horsepower easier than the /4

I'm betting that hp per liter would be the same and if anything, the /8 would be under more stress if you try to push it too hard.....

Posted by: jwalters Jan 28 2005, 06:06 PM

An aviation supplier / builder / design company called "Able Experimental" has done this with full success--albeit a T1 engine---Developed over 210 HP and almost 280 ftlb of TQ---key was 90.5mm P/C and a 80mm stroke---it was made for experimental aircraft--the same company makes the altimizer carburetor--this is an injected carburetor which automatically compensates the mixture for changes in air density--very popular carb in aviation.

Posted by: Jake Raby Jan 28 2005, 06:10 PM

It won't cost a whole lot for me to do it, other than the crank and heads... The rest of it I have gobs of....


Its all in time and putting the imagination to work..

Its no fun if you don't push the envelope.... I'm sure I'd learn something beneficial to my other normal engines from doing it!

Posted by: Mueller Jan 28 2005, 06:13 PM

QUOTE (jwalters @ Jan 28 2005, 05:06 PM)

An aviation supplier / builder / design company called "Able Experimental" has done this with full success--albeit a T1 engine---Developed over 210 HP and almost 280 ftlb of TQ---key was 90.5mm P/C and a 80mm stroke---it was made for experimental aircraft--the same company makes the altimizer carburetor--this is an injected carburetor which automatically compensates the mixture for changes in air density--very popular carb in aviation.

considering thier 100 hp /4 motors cost $6000, I'd hate to see the price of that /8 motor

they do have some cool stuff...

Posted by: jwalters Jan 28 2005, 06:28 PM

Yea they do---imagine there is allot of machining and welding up a crank and cam and MAGNESIUM case ( Can you say,,sparkler??) Those engines require even more prep than or = to Mr. Raby does to his to make them a viable high power aero engine If the balances of the entire assembly are off more than .10 inches per second the crank will grenade itself--even at the max rpm of 3600 these engines are rated for--and bye bye propellor--the cranks are rough prepped by CB's--they actually forge a crank just for this purpose---kool stuff indeed

Don't know ifn I would ever get into something like that, manufacturing wise--the liability factor is an ass pucker!!!

But it would be kool to see Jake the man do it---400+HP anybody???

I myself have a really doable engine make-up I am dreaming of---it uses the stock bottom end--but the cyl and up is off the shelf from a manufacturer that has been in business since 1908--

Not going to reveal it yet,,need to get measurements and geometric values looked at--plus I don't want to get sand bagged just yet!

Posted by: Bleyseng Jan 28 2005, 06:48 PM

screw two motors! put four of them together!


Attached image(s)

Posted by: redshift Jan 28 2005, 06:59 PM

QUOTE (Mueller @ Jan 28 2005, 08:13 PM)

considering thier 100 hp /4 motors cost $6000, I'd hate to see the price of that /8 motor they do have some cool stuff...

Uhh... excuse me, but doesn't everyone's /4 run about $6k?



Sounds CHEAP for FLYING.


M

Posted by: Bleyseng Jan 28 2005, 07:01 PM

I am hoping to squeeze by with $5000,
buying that Passat stole the rest of my milk money!

Posted by: Jake Raby Jan 28 2005, 08:16 PM

Here it cost 6K for a stock rebuild, but you can add 50HP for another 2500 in most cases.

5000 will go a long way really soon, especially in the beginning!

Posted by: r_towle Jan 28 2005, 11:23 PM

how would you do oiling on the rear engine???

Seems like you would have to eliminate the oil pump on the rear engine and connect the two oiling systems in some way...

Rich

Posted by: Brando Jan 29 2005, 05:12 AM

or connect them at the cranks...

if you're going that far, might as well go the route of merging two 911 cases...

Posted by: SpecialK Jan 29 2005, 05:18 AM

Screw pistons...........someone stick a Huey Turbine in a 914 (hey...I saw an Allison V12 in a Opel GT once....."point and shoot" as someone put it)

Posted by: BigD9146gt Jan 30 2005, 03:19 PM

QUOTE (Jake Raby @ Jan 28 2005, 01:47 PM)

Nah.... Can't make a statement with a 911 engine! Plus, they cost too damn much to play with at this level.. I'm using 964 heads though.. Engine will go in a mid engine 1961 VW Single cab truck, under the bed.....

911's cost too much to play with at this level???

1) What would two used long blocks go for? $2000?... ya, possibly more, but my friend just picked up a complete 69 911E all original with minimal rust for $1000. Deals are out there if you keep your eyes open, and thats what we're talking about.

2) If you charge $6000 for your base motor, and i was paying you to build a flat 8, you would have to charge $50,000 to even think about braking even. Odds are, if someone is going to be making something of this magnitude, they would't be paying you or anyone else to do it, cause for that price lots of other things could be aquired.

3) Lets think about how the factory made larger motors. The 908 and 917's for example, have very close relations to the 901 engine being over head cams, single heads, etc. Porsche and his crew were very brite, and if they chose a design similar to the 901 for their larger motors, i'm gonna say it wasn't because they listed all the options on the table and played spin the bottle to choose? Think about whats already done? Dry sump, single heads-better flowing, overhead cams, stronger crank, just a better-overall design from the get-go.

4)This is a project for someone who can do all their own work (like you and me).

Jake, i respect your work, but stick to what you know. Last time you were on the 911 bird forum, you started out high and mighty, but had zero answers. If you actually worked with 6's, you wouldn't say what you do about them... and i wouldn't be typing right now.

Again, you are a phenominal VW aircooled 4 cylinder guru.

Posted by: Air_Cooled_Nut Jan 30 2005, 03:57 PM

Yeah, deals are out there if you wanna WAIT for them and are constantly searching for them Anyway...

After reading about the Ferrari's and Lambo's that have eight plus cylinders and how folks drool over the carbed versions of these engines I think it would be something neat. Heck, you wouldn't need monster big jugs, either, as these cars didn't, just lots o' cylinders. My initial guess would be getting two balanced STOCK engines and make sure the timing 'tween the two engines was spot on, then mate 'em From what I read, the older Ferrari eight cylinders run like two, four cylinder engines mated together, which also contributes to their distinct sound. I'm guessing their cylinder firing order is different than American V8's.

Now, getting a vehicle to accept the engine is another issue. But from my point of view I think it'd be neat and who gives a crap if it's already been done before? If you were successfull and DOCUMENTED it so others could follow you could develope a cult following

Posted by: jwalters Jan 30 2005, 05:19 PM

Just do like the fiero / lambo conversion guys---stretch that puppy and put a flat 12 lambo in it!!!

THAT would be kool to say the least----

Posted by: r_towle Jan 30 2005, 06:09 PM

ok,

When if any was the earliest time that an overhaed cam was used on a /6 motor???

I have never taken one apart....yet...

Rich

Posted by: DuckRyder Jan 30 2005, 06:18 PM

Thinking out loud:

Couldn't you slice one case disecting it between the bores (that would require an angle or zig zag)

then slice the ends off of the other case to insert it in between the front and back of the other two halves.

That make sense?

Posted by: r_towle Jan 30 2005, 06:37 PM

QUOTE (DuckRyder @ Jan 30 2005, 04:18 PM)

Thinking out loud: Couldn't you slice one case disecting it between the bores (that would require an angle or zig zag)  :sawzall: then slice the ends off of the other case to insert it in between the front and back of the other two halves.  :welder: That make sense?  :blink:  :burnout:

ok, ill bite, why would i do that versus cutting the back off one and the front off the other.......

BTW It looks like the oil galleys can line up if it is cut in the correct place.

I would go with a dry sump.

Rich

Posted by: BigD9146gt Jan 30 2005, 07:05 PM

Rich, before i start in on Air Cool'd, the 901 (911) was an overhead cam from the get-go. They had some drawings for a single cam like the TIV, but it didn't prove itself like the overhead cams. The first 911 was in '65, but the project started in about '60. It wasn't set in stone till '63 or so, because Porsche wasn't sure if they wanted to go with a 356 looking car or not. Granted the 911 is close to the 356, they had other designs that they were looking at. Also, there was the 356 Carrera engine, which was the 4 cam motor back in the early '50s (550 spider). They the 901 had its first twin cam race engine in '67 for a few of the 911R's, which were 2.0L with around 200bhp.

QUOTE

Yeah, deals are out there if you wanna WAIT for them and are constantly searching for them  Anyway...

Ok, whats your point? Isn't that the point of a "good deal", or are we thinking like typical americans who want a good deal 365 days with no effert or quality?

QUOTE

After reading about the Ferrari's and Lambo's that have eight plus cylinders and how folks drool over the carbed versions of these engines I think it would be something neat.  Heck, you wouldn't need monster big jugs, either, as these cars didn't, just lots o' cylinders.  My initial guess would be getting two balanced STOCK engines and make sure the timing 'tween the two engines was spot on, then mate 'em   From what I read, the older Ferrari eight cylinders run like two, four cylinder engines mated together, which also contributes to their distinct sound.  I'm guessing their cylinder firing order is different than American V8's.

Ya, its called a 944 and a 928... The only difference is the crank and block. Same heads, pistons, rods, etc. But just because it has half the cylinders doesn't make it easy to make over. I too don;t know what the firing order is, but a 6/8 cylinder engine is WAY more naturally balanced than a 4 cylinder engine. In fact, the 6/8/12 cylinder engines are the the best for being balanced.

QUOTE

Now, getting a vehicle to accept the engine is another issue.  But from my point of view I think it'd be neat and who gives a crap if it's already been done before?  If you were successfull and DOCUMENTED it so others could follow you could develope a cult following

Cults are for those who like Coolaid. If a project like this ever made it to production, there would be very few who would undertake it. Just like Mr. Polopulus (sp), the guy who took the 901 and chopped two cylinders off and made a 4 cylinder for the 356 croud. The motor is around $15000, but that croud spends more money than the 914 croud.

I'm not by any means saying use the 901 because its expesive, but to the same measure, don't use a TIV because its cheap. Your going to be spending money either way you look at it, so why not start with a better designed engine and parts?

Posted by: DuckRyder Jan 30 2005, 07:21 PM

QUOTE (r_towle @ Jan 30 2005, 08:37 PM)

QUOTE (DuckRyder @ Jan 30 2005, 04:18 PM) Thinking out loud: Couldn't you slice one case disecting it between the bores (that would require an angle or zig zag)  :sawzall: then slice the ends off of the other case to insert it in between the front and back of the other two halves.  :welder: That make sense?  :blink:  :burnout: ok, ill bite, why would i do that versus cutting the back off one and the front off the other....... BTW It looks like the oil galleys can line up if it is cut in the correct place. I would go with a dry sump. Rich

Hey, I said I was thinking out loud.

I thought that it would match up better that way - possibly.

It has been a while (thank god) since I've seen one bare though.

Posted by: URY914 Jan 30 2005, 08:09 PM

Here's what you need...


Attached image(s)

Posted by: redshift Jan 30 2005, 08:11 PM

QUOTE (Special_K @ Jan 29 2005, 07:18 AM)

Screw pistons...........someone stick a Huey Turbine in a 914 (hey...I saw an Allison V12 in a Opel GT once....."point and shoot" as someone put it)

That car was on Ebay..

LOL Paul! Is that your new class ride?



M

Posted by: r_towle Jan 30 2005, 08:14 PM

QUOTE (URY914 @ Jan 30 2005, 06:09 PM)

Here's what you need...

looks kinda heavy to me.

I know you looked at it and said, hey he could make it lighter if he did this and this and this....

Rich

Posted by: URY914 Jan 30 2005, 08:18 PM

QUOTE (r_towle @ Jan 30 2005, 06:14 PM)

QUOTE (URY914 @ Jan 30 2005, 06:09 PM) Here's what you need... looks kinda heavy to me. I know you looked at it and said, hey he could make it lighter if he did this and this and this.... Rich

I've been working like crazy on my car. I gotta get it back together enough to take it to Sebring in two weeks to get it weighed. My day job and family keep getting in the way

Paul

Posted by: Air_Cooled_Nut Jan 31 2005, 11:23 AM

QUOTE

Ya, its called a 944 and a 928... The only difference is the crank and block. Same heads, pistons, rods, etc. But just because it has half the cylinders doesn't make it easy to make over. I too don;t know what the firing order is, but a 6/8 cylinder engine is WAY more naturally balanced than a 4 cylinder engine. In fact, the 6/8/12 cylinder engines are the the best for being balanced.

Okay, ya lost me. What's yer point? My bit on the Ferrari wasn't a suggestion of how to fire it but as to a contribution to its sound.

QUOTE

Cults are for those who like Coolaid[sic]. If a project like this ever made it to production, there would be very few who would undertake it.

I meant it like people doing it themselves for fun, not to actually make a production engine that people would buy.

QUOTE

Your going to be spending money either way you look at it, so why not start with a better designed engine and parts?

I agree with this logic. But I guess my message was too subtle as I was thinking about the SOUND of a multi-cylinder, carbed air-cooled engine.

I'm not denying that a 901 engine is likely a better candidate from an engineering standpoint so here, this one's on me

Posted by: jwalters Jan 31 2005, 02:47 PM

Wonder how the T4 would respond with a crank that has throws at 90 degrees at each other--instead of the 180 degree config---this and change the firing order to reflect a burn event on one side of the engine at a time--like : 1, 3, 2, 4

Instead of one side-followed by two same side, then last one side again---: 1, 4, 3, 2---

There would have to be a radically ground cam for this--


Ala Ducati--if the Duc had four cylinders.......

Posted by: bondo Jan 31 2005, 02:50 PM

QUOTE (jwalters @ Jan 31 2005, 01:47 PM)

Wonder how the T4 would respond with a crank that has throws at 90 degrees at each other--instead of the 180 degree config---this and change the firing order to reflect a burn event on one side of the engine at a time--like : 1, 3, 2, 4 Instead of one side-followed by two same side, then last one side again---: 1, 4, 3, 2--- There would have to be a radically ground cam for this-- Ala Ducati--if the Duc had four cylinders.......

I don't think you could grind a cam THAT radically, as 2 lifters are riding on each lobe, one for each side of the engine. By design it has to be 180 degrees apart.

Posted by: r_towle Jan 31 2005, 05:28 PM

yes, but what if you welded up the two motors to be in the 90 degree position???

That is what I was thinking....

Rich

Posted by: DuckRyder Jan 31 2005, 05:45 PM

QUOTE (jwalters @ Jan 31 2005, 04:47 PM)

Ala Ducati--if the Duc had four cylinders.......

Trying to make a desmo valve system work without overhead cams would be ... probably impossible.

Once you've adjusted the valves on one, you won't ever try to convert something TO Desmo.

And there is a 4 cylinder Ducati, the DesmoDeci (vs DesmoDue)





DuckRyder

Posted by: jwalters Jan 31 2005, 05:52 PM

Very nice pic of a Duc!!! I am spanking to it right now----always wanted one--900SS super light was the one that I lusted for--

I did not mean use the valvetrain--no--I was thinking of the inherent smoothness of a 90 crank--but because the cylinders are still 180 deg. the extra two throws would balance out like it was a 90 deg. crank in a 90 deg. cylinder layout-

And yes-those cam lobes would have to be whittled down in width quite a bit--but it could be done......

Posted by: DuckRyder Jan 31 2005, 05:56 PM

QUOTE (jwalters @ Jan 31 2005, 07:52 PM)

Very nice pic of a Duc!!! I am spanking to it right now----always wanted one--900SS super light was the one that I lusted for--

God, I wish I had never sold my 96 900 SuperSport SP!

Back to your regularly sceduled thread...

Posted by: JmuRiz Jan 31 2005, 11:06 PM

I know were're getting off topic here, but mmmmmmm Desmosedici = very nice. Man are they fast in testing this year too, wow. Looks like another fun MotoGP year.

Posted by: BigD9146gt Feb 1 2005, 12:34 PM

Nathan, I second that! MotoGP sould be great this year!

Duck, good point!!! Even though the Desmo is an awsome working system, the adjustments that are required to keep them up to spec are extreamly time consuming.

Its like the early 356 Carrera 4 cam motors... book time is 40hours!! I'm not kidding. They figured it would take you 3 times to get it right... Its all bevel gears and shafts, first you adjust the exhaust cam, then the intake cam. Pro's know how to compensate so that once they tighten the intake cam gear, the exhaust doesn't move. The good thing is once the adjustment is done, you never have to adjust it again solong as nothing breaks!

Posted by: Al Meredith Feb 27 2006, 06:34 PM

I was out at Chuck Beck house (he lives outside Atlanta now) last fall and the first thing I saw was a 4 cylinder 911 engine he built. I can't remember when he did it but I would say early 80's. I also have an old HOT VW's Mag from the "energy crisis" days where they built a 2 cylinder Ty1. I think there is an aero ty 1 engine that runs 2 cylinders on the same side.

Posted by: Mueller Feb 27 2006, 06:36 PM

QUOTE (Al Meredith @ Feb 27 2006, 05:34 PM)

I was out at Chuck Beck house (he lives outside Atlanta now) last fall and the first thing I saw was a 4 cylinder 911 engine he built. I can't remember when he did it but I would say early 80's. I also have an old HOT VW's Mag from the "energy crisis" days where they built a 2 cylinder Ty1. I think there is an aero ty 1 engine that runs 2 cylinders on the same side.

you can buy a 2/3 911 engine brand new now.....bring money, I want to say just the bare block casting (new) is $10K or something crazy like that....

Posted by: Cap'n Krusty Feb 27 2006, 06:37 PM

QUOTE (Al Meredith @ Feb 27 2006, 04:34 PM)

I was out at Chuck Beck house (he lives outside Atlanta now) last fall and the first thing I saw was a 4 cylinder 911 engine he built. I can't remember when he did it but I would say early 80's. I also have an old HOT VW's Mag from the "energy crisis" days where they built a 2 cylinder Ty1. I think there is an aero ty 1 engine that runs 2 cylinders on the same side.

Ya coulda bought a REAL Porsche flat 8 yesterday at the Ustabedunkel's swap meet! The Cap'n

Posted by: Mueller Feb 27 2006, 06:40 PM

QUOTE (Cap'n Krusty @ Feb 27 2006, 05:37 PM)

QUOTE (Al Meredith @ Feb 27 2006, 04:34 PM) I was out at Chuck Beck house (he lives outside Atlanta now) last fall and the first thing I saw was a 4 cylinder 911 engine he built. I can't remember when he did it but I would say early 80's. I also have an old HOT VW's Mag from the "energy crisis" days where they built a 2 cylinder Ty1. I think there is an aero ty 1 engine that runs 2 cylinders on the same side. Ya coulda bought a REAL Porsche flat 8 yesterday at the Ustabedunkel's swap meet! The Cap'n

what was the asking price?

is this part of the stolen Volask motor horde??

Posted by: cbenitah Feb 27 2006, 07:10 PM

QUOTE (Cloudbuster @ Jan 28 2005, 12:23 PM)

Hans Dahlbeck?

Ahh a swede, I should find out if its a relative.. imagine the typ of engine I will have when I'm done

Posted by: Mueller Feb 27 2006, 07:15 PM

QUOTE (cbenitah @ Feb 27 2006, 06:10 PM)

QUOTE (Cloudbuster @ Jan 28 2005, 12:23 PM) Hans Dahlbeck? Ahh a swede, I should find out if its a relative.. imagine the typ of engine I will have when I'm done

I do less favors for relatives than I do for friends

you wouldn't get squat from me, hahahaha

I wonder if he ever moved over here to the US as the article states???

Posted by: ClayPerrine Feb 27 2006, 07:51 PM

How about something like this???

Posted by: Mueller Feb 27 2006, 07:52 PM

QUOTE (ClayPerrine @ Feb 27 2006, 06:51 PM)

How about something like this???

okay, spill the beans...whos 914 is getting that???

Posted by: Aaron Cox Feb 27 2006, 08:00 PM

i wanna say thats a photoshop.....

nice 907/908 motor

Posted by: rick 918-S Feb 27 2006, 08:01 PM

Dude! is that at your house? Thant thing is awesome!

this whole subject to me is about the cool factor. I like the idea of tryin to build a a flat 8 from a bucket of parts and a tig welder. Who cares if it can even run. I would be cool to try.

Posted by: bd1308 Feb 27 2006, 08:02 PM

i'll see if i can dig up two bus motors....

The VW guy owes me....

b

Posted by: Brian Mifsud Feb 27 2006, 08:22 PM

Mike...while your in there pouring aluminum, how about adding a few more pounds to the crucible.....

Do a straight 8 using the 911 heads arouind a chevy crank???

Posted by: Brando Feb 27 2006, 08:23 PM

QUOTE (Aaron Cox @ Feb 27 2006, 06:00 PM)

i wanna say thats a photoshop..... nice 907/908 motor

Ding ding ding! We have a winner! It is photochopped.


Attached thumbnail(s)

Posted by: ClayPerrine Feb 27 2006, 08:27 PM

FINALLY!!!

I was wondering when someone would pickup on the errors in my picture.



I actually would LOVE to do this. I have been thinking about it for a long time. I want to make molds of a 911 case, and make wax castings to cut apart to stretch. Then make molds for the stretched cases and cast them.


I would use a 3.6L case. If I were to do this, I would want to go BIG displacement!!!

Posted by: Brian Mifsud Feb 27 2006, 08:28 PM

Photoshopped??!! Well, if I were designing this thing in CAD, you'd do almost the equivalent in terms of "cutting and pasting" (well sort of)... this picture is excellent inspiration though for a very doable flat 8 using 911 parts and some off the shelf V8 stuff...


Mike.. think Propane, propane, Propane......

Posted by: ClayPerrine Feb 27 2006, 08:33 PM

The crank would have to be custom made. That would be the big expense. The cams and cam carriers could be made from existing 911 parts. Just cut and paste using a welder and a dial indicator for the cams. Setup each cylinder as if it were #1. Get the cams onto the proper lift with the crank at the correct degree setting and weld them together.


Make an extended oil pump drive shaft, and a flat fan. Use a distributor cap from a mercedes v-8.


It's doable, it would just take time, paitence, and money.



And it would be REALLY cool in a 914....... 4.8L air cooled flat 8.

Posted by: ClayPerrine Feb 27 2006, 08:36 PM

Mueller... you up for making a couple of custom cranks?

Posted by: Thorshammer Feb 27 2006, 08:42 PM

Well Actually no, never thought about doing a type four engine, However, my little devious mind has always wanted to do a three liter V8 using two Hyabusa (GSX1300 Suzuki) That have been over bored using a billet block and a custom crankcase and dry sump oiling system. Thought I would put it in a small formula car for hillclimbs. Used to get 260-280 out of 1480cc Bus motors back in the day, So I would say 475-480 on good gas would be the number. BTW, the reason you can't get double the hp is due to friction. More parts means more friction, there is a point of diminishing returns when it comes to adding cylinders. That it why many F1 cars stopped development on V12's. V10 WAS The best choice. now just freaking V 8's they suck.

The other idea I had was to use two FZR400 Yamaha Cylinders and heads and a custom made crank using the stock bore, but reducing the stroke so that I retained 640cc. This would give me a really nice bore to stroke ratio, and after some intake port epoxy and a scatter cam (one inlet valve opens before the other one to promote swirl) I think I could make 130-135 hp out of this one. Very cool. Counter rotating barrel valves, and injection with 4 valve cylinder heads. Very high tech, and very cool sounding. Would be a great FSAE engine. Little tiny gasps of air through that 20mm orifice. Yes, yes, yes, Oops I soiled myself.




Erik Madsen

Posted by: Brian Mifsud Feb 27 2006, 08:42 PM

Hi Clay,

When you say a custom crank MUST be used, is that because the Porsche head and barrels are at too wide a pitch(i.e spacing of journals vs barrel width)??

Otherwise, just customize the parts AROUND the cheap crank.....

Intention would NOT be to be a 908 replica, but just a powerful lightweight flat 8 that can slip into the engine compartment without hacking it all up...

Posted by: ClayPerrine Feb 27 2006, 08:46 PM

QUOTE (Brian Mifsud @ Feb 27 2006, 08:42 PM)

Hi Clay, When you say a custom crank MUST be used, is that because the Porsche head and barrels are at too wide a pitch(i.e spacing of journals vs barrel width)?? Otherwise, just customize the parts AROUND the cheap crank.....

Nope. The porsche crank uses a separate rod journal for each cylinder. So we need to add 2 more rod journals and 2 more main journals.


I suppose you could cut up a BUNCH of 911 cranks and put together something that would work. But I would not try it with a custom made case.


And I don't know what firing order to use either.


This idea really gets me thinking... This would be SO cool with 4 dellorto/weber style throttle bodies and electronic fuel injection. Bet it would sound really nice too...

Posted by: alpha434 Feb 27 2006, 08:51 PM

If you do a different firing order, then you'll have to do custom cams to match the new crank.

I would just offset one engine's crank 45 degrees. Exactly. Then no two cylinders are ever firing at once, and you could use a V8 ignition system, since all timing would be evenly spaced.

We're all lucky that flat engines are naturally counterbalanced.

Posted by: Brian Mifsud Feb 27 2006, 08:51 PM

QUOTE (ClayPerrine @ Feb 27 2006, 06:46 PM)

QUOTE (Brian Mifsud @ Feb 27 2006, 08:42 PM) Hi Clay, When you say a custom crank MUST be used, is that because the Porsche head and barrels are at too wide a pitch(i.e spacing of journals vs barrel width)?? Otherwise, just customize the parts AROUND the cheap crank..... Nope. The porsche crank uses a separate rod journal for each cylinder. So we need to add 2 more rod journals and 2 more main journals. I suppose you could cut up a BUNCH of 911 cranks and put together something that would work. But I would not try it with a custom made case. And I don't know what firing order to use either. This idea really gets me thinking... This would be SO cool with 4 dellorto/weber style throttle bodies and electronic fuel injection. Bet it would sound really nice too...

OKAY, so that IS because of the Pitch (or spacing) of the Porsche cylinder that THEY use individual journals.... That doesn't mean it MUST Be engineered that way from scratch. The OFFset of one bank to the other would dictate whether I needed to use individual journals.. since I could control the offset.. I COULD use the chevy crank...(and distributor, rods, flywheel... maybe more...)

Posted by: Cloudbuster Feb 27 2006, 08:52 PM

QUOTE (Thorshammer @ Feb 27 2006, 06:42 PM)

The other idea I had was to use two FZR400 Yamaha Cylinders and heads and a custom made crank using the stock bore, but reducing the stroke so that I retained 640cc.

Just in case you didn't know, somebody is most of the way there

http://home.mira.net/~iwd/

Posted by: alpha434 Feb 27 2006, 08:53 PM

Can't use a chevy crank for a flat 8.

Posted by: rick 918-S Feb 27 2006, 08:53 PM

Here's a thought, use a crank from a V8 engine like a Chevy small block. Build a case around it, and add cylinders and a custom cam. Easy peasy...

Posted by: ClayPerrine Feb 27 2006, 08:54 PM

QUOTE (alpha434 @ Feb 27 2006, 08:51 PM)

If you do a different firing order, then you'll have to do custom cams to match the new crank. I would just offset one engine's crank 45 degrees. Exactly. Then no two cylinders are ever firing at once, and you could use a V8 ignition system, since all timing would be evenly spaced. We're all lucky that flat engines are naturally counterbalanced.

Won't work. It's not a type 4. It's a flat 6 that is getting stretched to a flat 8.


And I already covered how to get the cams correct.

Posted by: Brett W Feb 27 2006, 08:56 PM

The 180 degree 8 has a problem with second order imballance. It will shake at most street rpm levels. Most of you guys don't want to deal with that.

The 917 12s had problems with harmonics and crank vibration. This is why the fan and oil pump are mounted in the middle of the engine. You have to do this to keep those items alive.

You are better off just buying a Porsche flat eight. They aren't that expensive, when you look at what is involved in making your own.

Posted by: Thorshammer Feb 27 2006, 08:58 PM

One of the problems must be the design of a crank that does not extend the overall length of the engine by too much. This could be a major problem. It will probably have to use rods that are adjacent to each other liek a small block to keep the cylinder bore spacing decent.

As for the previous comment about bevel drive gear Carrera engines needing 40 hours to build. Yes that is true, if they are a new parts build up. However, if the time is taken upon disassembly to check tolerances and shims are kept in the proper order, then it is less than that. many Carrera Maestros (HA, HA, HA) keep the black art thing going to ensure no one else plays with them. Ensuring they have a place from now forth. But the main issue with 4 cam engines is parts availability or the ability to make some part that are NLA. This is the real issue. and thats why only two guys in the country do most of the 4 cam work. its either MT or CT, anything else is just a myth.
If you can work on a bevel drive Ducati, you can work on a carrera 4 cam.

BTW, why not make the V8 Type four monster use some Ducati Desmo air cooled cylinder heads. I have built many of those engines, the best we ever got in 750cc form was about 90-92 hp depending on the day. Which would mean 225 hp or so from 2.0 liters and 450 from 4.0 liters.
Just a thought.

Erik Madsen

Posted by: alpha434 Feb 27 2006, 09:03 PM

Why we couldn't use a Chevy crank:

Counter balancing, and angle offsets for timing.


A 60 degree V8 with a firing order 1-2-3-4-5-6-7-8

and shaped like this

1----2
3----4
5----6
7----8

The crank is at 0deg for 1. The crank is machined so that the piston one is -30 deg off center. Two is 45-30=15. Three is 60. Four is 95.

Posted by: ClayPerrine Feb 27 2006, 09:06 PM

QUOTE (Brett W @ Feb 27 2006, 08:56 PM)

The 180 degree 8 has a problem with second order imballance. It will shake at most street rpm levels. Most of you guys don't want to deal with that.

The second order vibration issue was solved in the second generation crank for the 908 engine. At the Fort Worth parade I talked with a guy who does restorations on 908s about this. He sent me the 908 firing order,but I lost that email when I left MS.


Anything longer than an 8 in a 911 style engine would make the crank too long. That would produce the torsional losses that they found in the 917 engine that prompted the center drive setup on it. Even the output drive on a 917 is taken from the center.

I figure if this could be done, then it would require a flat fan. Any ideas on it?

Posted by: alpha434 Feb 27 2006, 09:07 PM

QUOTE (alpha434 @ Feb 27 2006, 07:03 PM)

Why we couldn't use a Chevy crank: Counter balancing, and angle offsets for timing. A 60 degree V8 with a firing order 1-2-3-4-5-6-7-8 and shaped like this 1----2 3----4 5----6 7----8 The crank is at 0deg for 1. The crank is machined so that the piston one is -30 deg off center. Two is 45-30=15. Three is 60. Four is 95.

Wait. I did that wrong.

You alternate add, subtract.


But the point is that with a flat crank, we're 180deg out. Not 60

Posted by: lapuwali Feb 27 2006, 09:18 PM

QUOTE (Cloudbuster @ Feb 27 2006, 06:52 PM)

QUOTE (Thorshammer @ Feb 27 2006, 06:42 PM) The other idea I had was to use two FZR400 Yamaha Cylinders and heads and a custom made crank using the stock bore, but reducing the stroke so that I retained 640cc. Just in case you didn't know, somebody is most of the way there http://home.mira.net/~iwd/

Not most of the way, but all of the way. Ian Drysdale started with FZR400 top ends (barrels and heads) on a custom case and crank. He did this in the mid 1990s, and has been continuing development for years both of his engines and the custom chassis he builds for these engines.

The Radical engine is essentially the same idea.

The wackiest design I've seen was a "V8" made by simply gearing the output shafts of two complete ZX-9 engines together to a common output shaft (one through an idler), with the engines sitting "cheek to cheek". This made complete engine changes very easy, as long as you had a supply of used ZX-9 engines. It was very wide, but was built for a class of sportcar racing that required two side-by-side seats, anyway, so the width wasn't a problem. I believe a pair of ZX-12 engines were used by the same guy in a different car.

Posted by: alpha434 Feb 27 2006, 09:22 PM

QUOTE (lapuwali @ Feb 27 2006, 07:18 PM)

The wackiest design I've seen was a "V8" made by simply gearing the output shafts of two complete ZX-9 engines together to a common output shaft (one through an idler), with the engines sitting "cheek to cheek". This made complete engine changes very easy, as long as you had a supply of used ZX-9 engines. It was very wide, but was built for a class of sportcar racing that required two side-by-side seats, anyway, so the width wasn't a problem. I believe a pair of ZX-12 engines were used by the same guy in a different car.

Like a W12?

Where do you guys find that stuff? These are Formula classes? All we have around here is SCCA.... F. Vee and Mazda star stuff.

Posted by: Brett W Feb 27 2006, 09:23 PM

Sorry I was referring to a 180 degree V8. Don't know much about the flat 8. I would guess it would be pretty close to balanced.

Posted by: JmuRiz Feb 28 2006, 09:31 AM

QUOTE (DuckRyder @ Jan 31 2005, 03:45 PM)

QUOTE (jwalters @ Jan 31 2005, 04:47 PM) Ala Ducati--if the Duc had four cylinders....... Trying to make a desmo valve system work without overhead cams would be ... probably impossible. Once you've adjusted the valves on one, you won't ever try to convert something TO Desmo. And there is a 4 cylinder Ducati, the DesmoDeci (vs DesmoDue)

Well, there are a zillion styles of demodromic valvetrains. I came across this site a while back, TONS of info, movies and pics of different systems. You can have gear driven valves w/o OHC engine...it's just not as easy

Posted by: r_towle Jul 21 2012, 04:37 PM

It's time for this to finally happen
Parts heading to the machine shop with a goal of a spring firing

Posted by: sixnotfour Jul 21 2012, 05:26 PM

wow a Aircooled Pushrod Flat 8

Posted by: seanery Jul 21 2012, 05:45 PM

QUOTE(r_towle @ Jan 28 2005, 02:49 PM)

Posted by: r_towle Jul 21 2012, 05:48 PM

Yes, you are.
At least it am staying in the family.

Posted by: BigD9146gt Jul 21 2012, 06:02 PM

Theres a guy down in Melbourne who has made flat 8's out of 6's, says they are really easy and has moulds for the 908 style fan shrouds... problem is my last boss has been trying to get parts off him for some years now. This is one of my all time projects I wish to make. Cudo's to you for trying it with the type 4 stuff... will be fun to fallow your progress.

Posted by: rick 918-S Jul 21 2012, 06:07 PM

Totally do-able with some planning. I'll be watc hing this one!

Posted by: Woody Jul 21 2012, 07:43 PM

Posted by: jwhcars Jul 21 2012, 08:58 PM

The 2 factory 914/8 cars had 908 engines in them. The orange one had the full race MFI engine, and the grey one had carbs and was de-tuned for street duty.
There is one in the Porsche museum.

Posted by: Dr Evil Jul 21 2012, 09:11 PM

I will be doing this someday if no one else does...probably even if they do.

Posted by: sixnotfour Jul 21 2012, 09:17 PM

Doc you should do a flat 12 Covair






V16 inspiration
http://www.gtspirit.com/2012/02/01/video-custom-speed-buggy-with-v16-engine/

Posted by: sixnotfour Jul 21 2012, 09:33 PM

and these heads;

http://members.home.nl/r.vd.meulen/photopage.htm?./pics/dist07.jpg


Attached image(s)

Posted by: sixnotfour Jul 21 2012, 09:48 PM

http://home.swipnet.se/motor/custom/

Posted by: seanery Jul 22 2012, 06:04 AM

QUOTE(jwhcars @ Jul 21 2012, 10:58 PM)

Posted by: Mueller Apr 13 2018, 07:43 PM

Back to the flat 8 talk....

Found out Ferrari uses flat-plane crankshafts in some of their V8's so I went on eBay and voila... I found this crank from a 328, 73mm stroke instead of the Porsche 908 66mm stroke.

Guy wanted $850 plus shipping, I offered about half that, he didn't quite tell be to F off, but I think he wanted to with his response, asked me to call if serious.

Anyway, while not as accurate as the 908 crank it seems like a cheap alternative.

Posted by: Elliot Cannon Apr 13 2018, 10:12 PM

There was a guy, Richard I think, who used to show up at the G&R all the time who planned to build an 8 cyl. type IV. Richard are you out there?

Posted by: billh1963 Apr 14 2018, 04:41 AM

Isn't there a guy working on casting new 3.6 cases? Maybe he could cast one for an 8

Posted by: Philip W. Apr 14 2018, 05:47 PM

QUOTE(billh1963 @ Apr 14 2018, 06:41 AM)

Posted by: Mark Henry Apr 14 2018, 06:35 PM

QUOTE(billh1963 @ Apr 14 2018, 06:41 AM)

Posted by: rick 918-S Apr 15 2018, 03:36 PM

QUOTE(Mueller @ Apr 13 2018, 08:43 PM)

Back to the flat 8 talk....

Found out Ferrari uses flat-plane crankshafts in some of their V8's so I went on eBay and voila... I found this crank from a 328, 73mm stroke instead of the Porsche 908 66mm stroke.

Guy wanted $850 plus shipping, I offered about half that, he didn't quite tell be to F off, but I think he wanted to with his response, asked me to call if serious.

Anyway, while not as accurate as the 908 crank it seems like a cheap alternative.

Posted by: Dave_Darling Apr 15 2018, 09:38 PM

There are people reproducing basically all of the parts of the 908 engine. You don't want to know what they cost....

--DD

Posted by: r_towle Apr 17 2018, 05:53 PM

QUOTE(Elliot Cannon @ Apr 14 2018, 12:12 AM)

Posted by: falcor75 Apr 17 2018, 10:50 PM

I know there was a Swedish guy building one and putting it in a buggy. Not sure if it was based on T1's or T4's.

edit: found this when searching....

https://www.youtube.com/watch?v=2GpMGPUMyXE

Posted by: sixnotfour Apr 18 2018, 05:31 AM

http://home.swipnet.se/motor/custom/

Posted by: sb914 Apr 18 2018, 06:55 AM

QUOTE(sixnotfour @ Apr 18 2018, 04:31 AM)

Posted by: campbellcj Apr 18 2018, 08:12 AM

Direct link to "boxer 8" page

http://home.swipnet.se/motor/custom/boxer8.html