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Posted by: trekkor Aug 15 2004, 11:43 PM

Some say go six, some say stay four or go BIG four.

At what point does the SIX take over?

I run a 90 hp four and have been told that my 'lil SIX will make me slower with my 130+ hp. PO says 245hp. Won't truly know 'til dyno day. Which may sway me.

What kind of weight increase are we talking about?

Will I enjoy the car more on the street with the SIX?
Because let's face it I run 1-2 a/x a month compared to my 200 miles street driving.

a/x season is coming to an end soon. I'll finish with the four.
My project will be during winter. If the SIX is bogus I'll put the four back in. Only my time with my car hobby has been spent. ( A few bucks, too. )

KT

Posted by: Brad Roberts Aug 15 2004, 11:47 PM

HP to weight ratio....

90hp@ 2100lbs

130hp@ 2300lbs

It will always be easier to accelerate and stop less weight.

The biggest mistake made by newbie drivers... adding power before they can drive. It is much easier to add power than it is to add driver.


B

Posted by: VegasRacer Aug 15 2004, 11:58 PM

You say 130 hp. PO says 245 hp. That's a BIG difference.

Posted by: trekkor Aug 15 2004, 11:59 PM

I understand the driver part, as I still am just a punk.

When I had Instructors on both my afternoon runs on Sat at Alameda I only lost 1 second compared to my runs without 200 plus pounds of Randal or Rob Ways ( sorry ).

With the added ponies why am I slower?

When does HP win out?

KT

Posted by: anthony Aug 16 2004, 12:14 AM

I've been totally enjoying blasting around in the 911SC I just picked up. Unlike a stock 914, it effortlessly accelerates and moves through traffic. From 3000rpms to redline it's a damn rocket ship. It could only be better with about 250hp on tap. :-)

stock 914 2L (2100lbs) = 23 pounds per hp
stock 911SC (2600lbs) = 14 pounds per hp

To me if you are going to go with a six conversion you should go for at least a 3L or 3.2L engine but using the engine you have could be good for the initial shakedown.

It seems like it comes down to a coin toss. It costs $10-12K to install a used 3.2L engine. It costs about the same for a 200hp big four with nickies except you get a new engine and it only takes a few hours to install. The type IV is also a lot cheaper to repair/refurbish. Pick your poison.

Posted by: trekkor Aug 16 2004, 12:20 AM

Yes it is.
PO is no longer with us, so all info on build is lost.
245 is the surviving family rumor.

Trekkor

Posted by: anthony Aug 16 2004, 12:24 AM

245hp is a big number. What engine configuration are you supposed to have?

Posted by: SirAndy Aug 16 2004, 01:07 AM

it'll take over your WALLET when it's time to do a rebuild ...

Andy

Posted by: Walter Aug 16 2004, 03:04 AM

Up to 2,7 ltr both engines can be made equally strong. The six will however always be heavier and therefore needs some extra hp to be equally quick.

The difference will eventually be reliability. The six will always have more reserve with that aspect. The four needs way more tricks to be reliable at the same hp rating. A big four will be high strung, whereas a six is just mildly tuned with about the same power.

Strangly (or logically) enough, thats where budget comes in: With Nikasils (standard on most sixes), dry sump (standard on sixes), mods to make the outdated underhead valvetrain lighter (well, you know what Porsche did for that one), a big 4 can be made very reliable and then probably costs about the same if you let others do the engine building for you.

Although this reaction may lead you to beilieve otherwise, personally I like the type 4 better. A lighter car (especially a type 4 with Nikasils) is always more fun to drive fast and as stated before, a type 4 can be build more easily by oneself than the six IMHO...

Good luck,
Walter

Posted by: ArtechnikA Aug 16 2004, 05:16 AM

at the point on the dyno curve when the six starts producing more power...

stroke and compression being equal (which they mostly are on the 1,7/1,8) a big piston will produce more torque than a little piston. a 2,0 4 will produce more low torque than a 2,0 6. the 6 is starting to get into the meat of its power curve about where a D-Jet cam is falling off the top.

on the road - plus or minus a little - the crossover point is around 70-ish -- this is why 4's tend to be quicker at AX - where the speeds rarely exceed 70 and the 6 carries more weight.

no matter what you do - there will always be SOME engine that makes more power and goes faster than yours. enjoy what you've got and learn to drive it - this includes keeping it in a rev range that's appropriate for the task at hand.

Posted by: 914Timo Aug 16 2004, 05:34 AM

I have to say that the six is a lot more difficult engine to maintaina. Think about valve adjusting .....

And there is tons of more places where it can drop oil

But, I love my six. I dont even need a radio. I love the song of six

Posted by: cnavarro Aug 16 2004, 06:29 AM

Hey Walter, glad to see you here!

I'm going to stay out of the /4 vs /6 debate. I can truely say I can be neutral now that I made cylinders for both :-)

Charles Navarro
LN Engineering
http://www.LNengineering.com
Aircooled Precision Performance

Posted by: Tom Perso Aug 16 2004, 07:06 AM

I am a perfect example of too much power and not enough driver...

A 2270 in the 914 on R compound tires and it was only my second auto-x. The car was a handful and it literally shot from corner to corner... I couldn't keep up with it!

Tom

Posted by: brant Aug 16 2004, 08:29 AM

I think the -6 really starts to take over when you factor in the higher redline and gearing advantages of a big track.
b

Posted by: Mark Henry Aug 16 2004, 09:52 AM

All I have is a stock /4 engine with a bit of a cam and the SDS EFI and the power rocks. They have dyno days at the local rolling road and I want to try it out to see what Hp I now have, my guess is 110-120. It was enough to keep up with a Ferrari 328 over the weekend, I'm pretty sure he would have cried if he knew my 914 is only a 4 banger.

I almost jumped on the six bandwagon when I first got my teen, but the costs were a bit too much for me. I might have been able to do a low budget /6 for the cost of my new 2.6 nickies engine, still it would be a lot more work fitting it in.

One thing about a /4 though, it will always sound like a VW at idle. The sixes do sound cool.

Posted by: Jake Raby Aug 16 2004, 10:21 AM

Keep it a 4, or slap in a V8... The six conversion doesn't even get a wink from me..... atleast the V8 makes enough power to afford the weight and you can build one dirt cheap...

"The only replacement for displacement is weight reduction" Keep that in mind and the 4 is very promising IF IT IS DONE RIGHT! Not many people hold the keys to unlocking the -4 in power and reliability. I have a full set in my pocket 24 hours a day.

Posted by: mack914 Aug 16 2004, 10:32 AM

Doing a 6 conversion. Putting the drive train in today. May not be doing all the right things. But, one thing I do know is the sweet sound of that 6 is worth the price.

Posted by: Jake Raby Aug 16 2004, 10:34 AM

Must have never heard a big four done right.. It'll drown the six in carbs alone.

Posted by: scotty Aug 16 2004, 10:59 AM

...sound

I drove a '75 1.8 for 15 years. I loved that car. The only time I wished for more power was at high altitude and/or climbing steep hills "in pursuit."

I now have a '74 with a 2.7 six. It's more fun/money/tinkering. It also makes me pay more attention when I'm driving. Stupid moves that a stock 1.8 -4 would let me get away with become much more "interesting" with the -6 (not driving a 914 for 10+ years doesn't help one remember skills).

Gas mileage is down with the -6, but the grins per mile index is waaay up.

I can imagine the grins to be had with an 8.

Posted by: anthony Aug 16 2004, 11:00 AM

The ferrari must have not been trying. A 120hp 914 can't keep up with a 250hp Ferrari unless it's on an autoX course.

Posted by: nine14cats Aug 16 2004, 11:01 AM

I have to say that on the big tracks...the 4's are in my review mirror...

I think it depends what you end up doing with the car and what type of power band makes you happy!

If you like the 4, go 4 if you like the 6 go 6...or go V8!

Truthfully, running with the zoomies....I don't see any 4's....

but that's on the track...on an auto-x or street, the 4's are really nice...

Bill P.

Posted by: theol00 Aug 16 2004, 11:11 AM

I have - an "anemic" 2.2 ltr e spec 6 in my car with Weber IDA 44 - and its done right - had a few 914 2ltr and 1.7ltr before they are different animals although a lot of fun -
I also have a 92 911 c2 with 250 hp - I would sell that car before I would sell my 914 - 6 2.2. I drive it on the track and on the street - the only thing I do is change tires. The car is reliable, low maintenance and it is a blast!

But you have to do what you think is right for you.

Posted by: J P Stein Aug 16 2004, 11:47 AM

We can (and have) had this discussion till we're blue in the face....and yet, it rages.

The answer (IMO) is: It's your money, do what you want..... but make sure you know what you want.

That said, I don't know anybody that has converted a 6 to a 4......Jake prolly does tho

V8? Sure, if you want a cruiser.....

Posted by: theol00 Aug 16 2004, 11:53 AM

JP Stein said:
That said, I don't know anybody that has converted a 6 to a 4......Jake prolly does tho




JP - I have to agree - that is the best argument I ever heard on this subject!

Posted by: john rogers Aug 16 2004, 12:11 PM

Having raced a stroker 4 that had 184HP at the rear wheels and a six that has 185HP at the rear wheels I have noticed the following things. The six is much more reliable, as we could get two races maybe on the four. The four had much more torque and was much easier to drive, even on a track such as Willow Springs. The six conversion needed an "V" top gear where the four was happy with an "X" top gear so I now have two transmissions. The slight extra weight from the six has actually made the car handle better, especially with the stiff springs/shocks we have. The car seems to stay "planted" much better on chicanes and turns.

Posted by: anthony Aug 16 2004, 12:22 PM

As John points out gearing is the other major issue here. I think people often skimp on this aspect of their conversion. A V8 is supposed to be awesome coupled with a 930 transmission and likewise a big six is great with a 915. That can add an extra $5-7K to the project which of course is why most people start off with the stock 901.

Posted by: jd74914 Aug 16 2004, 12:25 PM

did i mention that i agree with you jp

whoever said small sixes aren't worth it . . . :finger2: . . . LOL

also, i've got access to 2.4ltr S (also e-spec), its fun in a 911, i want to try it in a 914

Posted by: Jake Raby Aug 16 2004, 12:28 PM

John went about his big four totally different than we do.. Those big cast iron 103s are the worst thing for reliability.

I do know of one six that was converted to a four- no joke.

Posted by: J P Stein Aug 16 2004, 12:58 PM

Hay *I* believe you.
Even a blind squirrel finds an acorn once in a while.

Did the fo...guy stick with the dry sump or go with a tuna can?

Posted by: Jake Raby Aug 16 2004, 01:26 PM

We dry sumped it... He kept the tank.

Posted by: Martin Baker Aug 16 2004, 01:48 PM

Amen...

Posted by: siverson Aug 16 2004, 02:46 PM

Hay! No way, I think I win that award!

-Steve
'74 914 3.6

Posted by: michel richard Aug 16 2004, 04:31 PM

It's hard to convert to a 4 after you've spent the big bucks on a "6". The fact it has'nt been done very often is not a huge argument (IMHO)

Oh, and a 2.2 E that's on carbs is, be definition, not done right. (Nomex on)

Michel Richard
High revving 2.2 E with MFI 914

Posted by: 9146986 Aug 16 2004, 05:23 PM

I think we've got a variety of issues rolled into one thread here.

First, for anyone that's owned a non 6 914, the 6's have a certain lure or mystique about them. You know, only 3400 built, half or so of that imported to the US. Of course anyone that's drove a real 6 with a tired engine would say "what's the big deal?". At 125hp the 2.0T engine is no awesome powerhouse. Fresh engine vs fresh engine, the 6 will be faster than a 2.0 four, but not by much.

When it comes to converting a 4 to a 6, you start into another realm. I think the point that Brad was trying to make, is that a few years after you get done it's very easy to look back and think "gee I should've spent the extra money and got a bigger more powerful engine". Once you start down the path of higher power engines, the pocketbook is the only limit.

I would respectively disagree that a good 2.2E or S isn't worth the effort though. 165hp in a 914 makes for a very well balanced car, and certainly much faster than a stock 2.0.

Just my .02 though, it's your car do whatever makes you happy.

PK

Posted by: trekkor Aug 16 2004, 05:26 PM

Ah, yes...

Keep it coming. I need it all. Thanks.

KT

Posted by: anthony Aug 16 2004, 05:30 PM

Hey, I'm driving a tired four!

Posted by: siverson Aug 16 2004, 06:06 PM

I agree, there are a lot of issues here.

I'll be the first to argue that the best bang for your buck is a dead stock four 2.0 with stock FI. They are really fun cars to drive, enough power, not too bad to maintain or rebuild.

Having said that, I've sunk a bunch of money into my six conversion and I love it and it's really fast, but it's not as good of "value" as a stock four. I.e. it's cost me 5+ times more money, but it's nowhere near 5+ times as much fun. Maybe 1.5 times more "fun", but really, how do you measure that... I don't regret spending the money on the 914, but there is some serious diminishing returns, and you have to know that when you get into it.

To get further off topic, the best bang for the buck toy I own is my 2000 Suzuki Bandit 600 motorcycle. Bought it used for $3500 with 2000 miles, probably could sell it now for $2500 with 6000 miles, and it's a blast to ride around and have loved owning it. In comparison, I just spent $3800 on the full Tec3 system for my 3.6...

-Steve
'74 914 3.6

Posted by: Gint Aug 16 2004, 06:49 PM

Sound familiar Trekkor?

I've had both. The small 6 may not be a monster powerhouse, but I want to hear that motor behind my head again so bad!

Posted by: thomasotten Aug 16 2004, 07:34 PM

Can someone break down for me the diferences between 2.2 E, S, and T? Does the T get you laughed off the island with the big six crowd? I would really like to know the differences in these three engines, and what one could expect to pay.

I too want to hear that sound

Posted by: Gint Aug 16 2004, 07:38 PM

Listen to the purple 914... sounds just like I remember my car - did. And hopefully will again soon.

http://914world.com/downloads/Videos/DynoDay.mov

Posted by: anthony Aug 16 2004, 07:45 PM

A 2.2T engine with 125hp seems like it would be hardly worth the effort.

I like this site for a quick rundown of all the various 911s:

http://www.idee.demon.nl/

Click on models and then on the page for each model there is a specifications page.

Posted by: ArtechnikA Aug 16 2004, 08:36 PM

good site.

if you want the real nitty-gritty details, they're in the Spec Book.
there's also overview in Anderson-1 and "911 Story"

a 2,2T had Zenith carbs. E and S had MFI. cam, compression, and detail differences after that.

but - 2,2's had the last of the short-stroke motors and the first year of piston squirters so running forged pistons and Nickies is do-able.

Posted by: 9146986 Aug 16 2004, 09:53 PM

I didn't have time to finish a couple other points in my prior post.

There is alot you can do to your 914 before you convert it to a six, that will make the six conversion that much better. Like suspension, brakes, transmission. I think it important to have an overall package you want to put together. What's good is an extra 50-70 hp (or 115) if it all ends up as inside wheel spin, or crappy handling, or marginal brakes?

I am guilty of having owned a 3.0 conversion, and really loving that car. There's nothing like the torque that engine puts out.

If I were to build that car now though, I would go with a 3.2 Motronic, because it works so well and you just turn the key. No snappity, pop, pop, time to clean the idle jets again. I would also like to build a car with a small displacement high revving engine too. Something like a 2.2S or even better a 2.4S with the 2.2S cams, with MFI for the throttle response.

The only problem is time and money, usually you've got only one at a time though!

PK

Posted by: trekkor Aug 16 2004, 10:11 PM

For all who missed my "Shall I say... SIX", saga.

Here's my motor again.

KT

I can't find the engine # right now.

Engine is across town.


Attached image(s)

Posted by: JmuRiz Aug 16 2004, 10:27 PM

Posted by: Aaron Cox Aug 16 2004, 10:29 PM

was it on a freakin boat???? or a sandrail?????

Posted by: phantom914 Aug 16 2004, 10:31 PM

Made for a dune buggy me thinks.

Andrew

Posted by: J P Stein Aug 16 2004, 10:45 PM

6 bolt cam covers = early aluminum case. 2.0L at one time.

Posted by: trekkor Aug 16 2004, 10:56 PM

Came out of a tube chassis desert racer.
Supposedly only 100 miles...one race. Carbs bogged when airborn.

JP, # is 901-06 with 8372 stamped below it in a different punch font.

KT

Posted by: seanery Aug 16 2004, 11:14 PM

Perry,
what size was the motor in the car you took me for a ride in at the MUSR last year?

Posted by: Steve Aug 16 2004, 11:33 PM

Power versus longevity a six will win hands down.
My stock 3.2 puts out 231hp.
I would love to see a 231hp four last as long my six.

Does anyone know of a 200k mile 231 hp four cylinder??

Steve

Posted by: Aaron Cox Aug 16 2004, 11:47 PM

thats not a fair deal.

it would be col if a four made 2/3 has much power and lasts as long. (4 cyl / 6 cyl = 2/3) .
if it made 66% as much power...and lasted as long. they would have equal longevity.

Posted by: J P Stein Aug 17 2004, 02:09 AM

Trekkor:

911/06 in stock form:

130 hp @ 6100
128f t/lbs @ 4200

9.01 comp ratio
Small port heads 32mm int & exh.

Anybody hot rodding this would open up the exhaust (& intake) ports. You can check the exh. ports with calipers.

Posted by: 9146986 Aug 17 2004, 07:16 AM

Sean,

That was a 3.2 Motronic. Except for the muffler (too resonant for me), that car was perfect.

PK

Posted by: iamchappy Aug 17 2004, 08:02 AM

I feel that Porsche should of offered the 914 with the same engines and running gear that were evolving on the 911 throughout it's production run. And if they had, we wouldn't have this debate. They had the right idea from the begining.

To simply think of it, if I had this as a factory option what would I want.

Posted by: ArtechnikA Aug 17 2004, 08:19 AM

MIGHT have happened if Karmann had continued to honor the handshake deal to provide bodies to Porsche for a price. but they raised the price on the shell and Porsche didn't have much choice but to pass the increase along. that brought the price of a 2,0 914/6 to within $500 of a 2,2 911 -- and buyers were quick to make their choice. (a 2,2 914.6 would probably have cost MORE because Reutter (owned by Porsche...) was making Zuffenhausen a pretty good deal on 911 bodies...)

by '72 the factory was getting heavily involved in international competition and with the introduction of the 2,7 911RS in 1973, they really didn't need the distraction on the assembly line that was pumping out profitable 911's as fast as they could.

One of Porsches hardest jobs now is finding ways to keep kneecapping the midengine Boxster so the 'entry-level' Porsche won't outperform the "flagship" 911. (996. 997. whatever...)

but this historical background just gives you an opportunity to do what economies made it impossible for the factory to do. and without 'Value Engineers' breathing down your neck trying to get you to cut (more) corners ...

Posted by: ! Aug 17 2004, 08:21 AM

Manfred is running a 2,0/6 "S" motor.....factory rated at a "bit" more than than the stock motor for that year, but more buzzy with molasses for pulling power below 4k rpms.....but boy does it zoom up to 7K fast......woof....

I'm doing the opposite of Bradholio.....going from a big six to a small bore....'cause I wants too...

Posted by: Root_Werks Aug 17 2004, 12:27 PM

Preference. It is all about what someone likes. I like the sound of a 6 over a 4 or 8 cyl car. The 914 is such a versitile platform you can put just about anything in one. But the flat 6 is still a Porsche engine designed from the start for the 914 just like the flat 4 was.

I have heard some people swing wieght around.

4cyl - 2100lbs
6cyl - 2300lbs

I haven't ever had a 914-6 that wieghed that much? Maybe 2250lbs tops? I have found once you take out the heavy 914-4 cross bar, heater boxes ect. The wieght trade off is about the same. My latest 914-6 conversion wieghs in around 2200lbs full tank of gas. 130hp 2.2T engine. That works, keeps me under budget, wife happy and is still plenty zippy for street use.

Posted by: Root_Werks Aug 17 2004, 12:30 PM

Before I am corrected, I will do it myself.

914-6 2300lbs - Depends on what the car was built to be. Most stock bodied 2.7 under 914-6's without external oil coolers and frame stiffening kits will wiegh less than 2300lbs.

There, I think I covered myself?

Posted by: ArtechnikA Aug 17 2004, 12:40 PM

close :-) ...

owner's manual number on a factory 914.6 DIN curb weight is 940 Kg - 2068 lbs
Spec Book HP on a 2,2T is 125 HP @ 5800

Posted by: carr914 Aug 17 2004, 05:39 PM

After owning 6 914's mostly 2.0 liters, a 914-6 2.2T conversion and a 914-6 with a 2.2S motor, I decided on a 2.5 liter twin-plug six for my latest conversion. I will agree with an earlier comment on getting the mods (brakes, suspension, etc.) done. I've been slowly doing the mods on this car for about 9 years. I've got 1989 Carrera brakes with Pagid pads on this car. My feeling is going over 250hp will need even better stopping power.

Posted by: Eddie914 Aug 17 2004, 05:53 PM

I agree with J P.

The 2.7 is a great compromise.

Since my mongrel weighs in at less than 2100 lbs, throttle response is very linear.

Eddie

Posted by: thomasotten Aug 17 2004, 07:36 PM

But.... isn't the 2.7 the one that has the pulled head-stud problem?

Posted by: Mueller Aug 17 2004, 07:41 PM

so you fix it before installing the engine into your 914...

the 2.7 is not a bad engine, it had some issues that can be addressed...

good chances they have already been upgraded and fixed depending on who owned the donor 911

Posted by: ArtechnikA Aug 17 2004, 07:45 PM

-had-

just like the 3,0 is the engine that had the broken head stud problem.

there are well-known fixes.

Posted by: carr914 Aug 18 2004, 05:19 PM

I was told that the main cause of stud failures in 2.7 was due to the Thermal Restrictor exhaust which caused massive heat buildup, but if you eliminate that mess you have a great engine case to work with in the 7R.

Posted by: ! Aug 18 2004, 05:42 PM

Yup....the add on EPA smog crap killed a LOT of engines back in the 70s and 80s.....HEAT is a bad thing for air cooled engines.

BTW...they were Thermal Reactors.

Posted by: ArtechnikA Aug 18 2004, 05:46 PM

Thermal Reactor...

it was a bunch of things. the massive heat was one. weak mag alloy case was one, combined with too-fine-pitch threads on the studs - which is why Case Savers are an effective fix. finally - there were the new all-aluminum Nikasil cylinders, that resulted in more cylinder axial expansion (and therefore more force) than the earlier cylinder materials produced.

add in the 5-bladed fan, which was actually done to INCREASE temps (to improve the effectiveness of the thermal reactors...) and the fact that Porsche finally started producing AC units that worked well enough that people started buying and using them in - you can see this coming - hot areas...

the last years of the 2,4 also used the 7R case and weren't subject to nearly the stresses - those are good cases to start with although you will need to have the cylinder spigots bored if you're looking at 2,7 or 2,8 ...