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914World.com _ 914World Garage _ Cost to go to 78mm stroke??

Posted by: Mueller Dec 13 2004, 04:59 PM

Seems like Jake will be out of reach for the next few weeks...so...anyone know the cost differance between staying at 71mm and upgrading to 78mm stroke?

my rods already need to be re-worked due to the pistons I'm going to use, so no loss there, I'm guessing new rods would be in order for the longer stroke....I have no idea what crank is going to cost, nor the rods....can a 1.8 crank be used so that I can at least sell my 2.0 rods and crank to help cover the additional costs??

Posted by: Cloudbuster Dec 13 2004, 05:08 PM

I got the impression from the Excellence article that 71mm cranks are fettled / welded by DPR to go to 78mm, so the 71mm crank is a core. As for 66m cranks, I get the feeling those aren't used since the 1911 package was floated to address excess 1.7/1.8 parts inventory. I think the 2.0 rods are a write off since T1 style wrist pins (22mm?) are preferred.

Posted by: Dave_Darling Dec 13 2004, 05:08 PM

Mike, get over to http://www.aircooled.net and look at the prices for stroker cranks and H-beam rods. Get Type I journals, as their rods are a lot cheaper than Type IV ones.

I don't know if a 78mm crank throw requires a reduced-base-circle cam or not. If so, that's extra work for you to do.

And don't forget all the time you will spend quadruple-checking everything and grinding down anything that interferes...

--DD

Posted by: DNHunt Dec 13 2004, 05:26 PM

Pistons, rods, 71mm crank as a core, reduced base circle cam and some clearancing of the case. It gets pricey. I'm not sure how much more.

Dave

Posted by: jwalters Dec 13 2004, 05:29 PM

I was told by the folks at Demello cranks that as long as you stay with no more than 78mm and use the type 1 rod with the inside bolts, that no clearancing should have to be performed--------they did say that on the odd chance you had one of those odd cases from a european bus then some work might need to be done, the key is CB style rods w/ the 22mm pin

Hope this helps beerchug.gif

Posted by: lapuwali Dec 13 2004, 05:30 PM

I'd love to hear a definitive answer to this. My impression is that 74mm is as far as you can go w/o having to worry about cam or case clearance issues, and 78.4mm is as far as you can go w/o having to grind bits of the case 100% of the time, and having to use the special cam.

Posted by: DNHunt Dec 13 2004, 05:33 PM

I just finished putting one together, The CB rods had a tiny bit removed and the case was clearanced by Jake. None of it was dramatic but it was definitly worked on.

Dave

Posted by: cgnj Dec 13 2004, 05:45 PM

Ok, here is my two cents.
66mm crank is a core. At 78.4 you will need a reduced base circle cam. I used Scat rods. I have not used the CB super rod. I have gleaned from STF that it requires little or no clearancing.
My crank was $450 from aircooled, no core. You may get a better deal with Demello or DPR, plus get a core for your crank.
CB super rods are about $270.
KBs are $300 at aircooled.
You should be able to fetch something with the 2.0 Crank and rods.
Machine your cylinders. Thats the difference.

Carlos

Posted by: my15window Dec 13 2004, 05:51 PM

I think I paid about 350.00 for his 76 crank, he balanced the fly wheel and ground down the rods He is the guy to go to though, he does all of F.A.T.S work and tons of other companies check out his web page, then check out FAT performances, cash talks too...

Posted by: Jake Raby Dec 13 2004, 05:52 PM

I can do it in my sleep guys... The clearance is nothing to worry about when you get all the parts from someone that KNOWS the clearances.

I don't use stock 2.0 rods for ANYTHING! 74mm stroke is no easier to build than a 78 with the right matching components. The problem to this point is finding THE person that can set you up with EXACTLY what works, clears, fits and won't break. If you buy many of the parts from establishments now you still have to clearance the rods, but where? How much do you take from them? Then you have to have them balanced!

Same goes for the camshaft.. How much of a reduced base circle? What will fit? How much is enough or too much lift??

The issue is having to buy a cam from one place, a crank from someone else, and rods from someone else- Thats about to become a thing of the past. blink.gif

BTW- I wouldn't use a crank other than DPR if someone held a gun to my head. Email me for some pics of "Others" work.... I spin DPR cranks with my design to over 8,000 sustained RPM with no sweat. One of my new customers this year threw a counterweight off of a Demello crank that went clean through the case and through the body of his F prod 914! It took out 15,000 bucks of other parts with it! All cranks are NOT created equal! Alot of them are made from cores that would not clean up for a stock job... I send my cores in for the work to be done and throw 1/4 of them away in the process of looking for the best ones. Its not uncommon to find cracked journals, loose fitting flywheels and etc from the "Others"....... Been there and done that!

here are the prices you asked for

Crank= 485.00 (TI journals)
Rods= 280
Clearancing = Included with rod price boldblue.gif
Camshaft= 175.00 (custom grind with reduced base circle designed for the heads being used as well as the crank/rod clearance)

Hell as far as the case clearancing goes if you buy the stuff from someone that puts their heart and soul into this you might even get a template of what to clearance and where to do it from! The clearance work is simple..

Building less than a 78 stroke is just plain a waste of time, this is super easy this way and give tremendous amounts of torque!

Ask DNHunt how easy it is to build when you do it my way... He knows first hand..

I can literally do it wearing a blindfold!

Patience guys... Patience... I'm working 18 hours a day trying to remedy these issues!

Posted by: Mueller Dec 13 2004, 06:42 PM

cool...thanks for the input everyone.....guess I'll be going with a stroker motor mueba.gif

now to sell my turbochargers before I get any more "bright" ideas, hahaha

Posted by: Jake Raby Dec 13 2004, 07:00 PM

Gimme 4-5 weeks :-)

Posted by: Mueller Dec 13 2004, 07:04 PM

no problem.........it gives me time to build the intake system for it welder.gif smash.gif

Posted by: bernbomb914 Dec 13 2004, 07:13 PM

mike I have the 78.4 from DTM cost was 425.00 I didnt need to worry about cam as it cleared. machined the case. bought spacers from rimco and push rods from rimco, they have to measured first. If I was to do it over I would have done a 76.4 stroke confused24.gif as that is as large as porsche goes. and I would use 102 nickys to get the Cubic Inches. just my opinion.

Bernie confused24.gif

Posted by: Jake Raby Dec 13 2004, 07:25 PM

78x102 is hard to beat...

The 102s are all mine now. Charles gave me the exclusive rights to them for all the research I have given him!

Posted by: Bleyseng Dec 13 2004, 07:33 PM

damn Mike, you gonna build a 102x78 monster for your daily driver 914? Kewl!

Geoff

Posted by: anthony Dec 13 2004, 07:35 PM

Jake is that 4-5 weeks before you have these kits for sale on the web site? Or 4-5 weeks to receive a crank/rods/etc. after an order?

I was going to build a 2056 but I think I should go 78xsomething.

Jake, just for the sake of curiosity, what is the approximate hp/torque for a 78x102 Nickies engine?

Posted by: Jake Raby Dec 13 2004, 07:42 PM

There are no approximates! I have had a 78x102 make 200HP and 200 on torque, and others designed for longevity make 180..

My standard base engine for a 78x102 makes 195 and 205 on torque at the flywheel. Thats of course with the heads that it REQUIRES. Big bores don't play with headwork!

It'll be 4-5 weeks until I can show you guys what I'm doing around here...

delivery times will be in days- Not weeks.

Posted by: jr91472 Dec 13 2004, 08:06 PM

ok, now I am getting excited boldblue.gif boldblue.gif

Posted by: Britain Smith Dec 13 2004, 08:35 PM

Here is a picture of the 78mm crank installed in my case with a reduced base circle cam. I have a Raby cam in their now, but you get the idea.

-Britain

IPB Image

Posted by: Randal Dec 13 2004, 08:56 PM

QUOTE
Here is a picture of the 78mm crank installed


Now that is beautiful! Can I borrow it for a few events?

Posted by: Mueller Dec 13 2004, 11:21 PM

QUOTE(Bleyseng @ Dec 13 2004, 06:33 PM)
damn Mike, you gonna build a 102x78 monster for your daily driver 914? Kewl!

Geoff

I wish.....nah, I'm being cheap and sticking with the 94mm bore...if I go with the hp per cubic centimeter of Jakes 2270 that uses sorta stock 2.0 heads, I should have 150 hp at the wheels....I hope so !!!!!

Watch out Trekkor, the /4's shall rule the auto-x field, LOL

Posted by: Jake Raby Dec 13 2004, 11:37 PM

Mike, thats gonna be tough..

You could change the arrangements with Charles and make it into a 96mm bore and a 2316 (80 crank) and get around 150 at the wheels..

The 80mm crank done my way is EASIER to install than a 78!

That 2316 combo is NASTY and still very drivable! Torque from hell and it pulls like mad with instantaneous throttle response!

Posted by: Mueller Dec 13 2004, 11:59 PM

tempting, but I'm going to have to draw the line someplace..."feature creep" is going end up costing too much money smile.gif


is 130hp at the wheels asking too much with the current 94x78 combo? Is the 94x80 combo something that can be done? If so, additional cost above and beyond the 78mm stroke.....

Posted by: Bleyseng Dec 14 2004, 12:07 AM

Why keep increasing the stroke? Why not increase the displacement to 102mm? Why not just do a 102x71mm engine?
Geoff

Posted by: Mueller Dec 14 2004, 12:17 AM

QUOTE(Bleyseng @ Dec 13 2004, 11:07 PM)
Why keep increasing the stroke? Why not increase the displacement to 102mm? Why not just do a 102x71mm engine?
Geoff

I believe these motors are more effecient with longer stroke combos..the cylinder is so big and with small valves that the motor needs the extra time for the stroke to go all the way down to really fill up the cylinder with air and fuel...something like that if that makes any sense smile.gif

the cost of going to 102's gets expensive real fast, the pistons cost more and I'm pretty darn sure at that level "real" head work is required......my heads are already done and most of the engine is paid for....or so I hope wacko.gif

Posted by: Aaron Cox Dec 14 2004, 12:23 AM

so go big stroke and an extra 2mm bore....cost less to bore out stock cyls....then it does for 102 nikkies....

you should start a donate paypal thing like i did!

im up to 7 cents..!!!! laugh.gif

Posted by: Mueller Dec 14 2004, 12:28 AM

QUOTE(Aaron Cox @ Dec 13 2004, 11:23 PM)
so go big stroke and an extra 2mm bore....cost less to bore out stock cyls....then it does for 102 nikkies....

you should start a donate paypal thing like i did!

im up to 7 cents..!!!! laugh.gif

I want the Nickies !!!!!!

I'm sure this won't be my last Type IV motor....I'll learn from this one and wait for Jake to keep on devoloping parts and combos..........

Posted by: Bleyseng Dec 14 2004, 12:46 AM

Cost the same for little Nikkies as it does for big Nikkies........

Geoff biggrin.gif

Posted by: crash914 Dec 14 2004, 06:52 AM

Mike, go with Jake on this one.....

I did it my self and had to redo just about everything....80mm crank...scat rods, I ground them down then ended up sending them to Jake, they work much better now...bought a reduced base circle cam...ended up getting another from Jake this time as it was even smaller and fit better...

His prices are what I spent not buying from him....then I re-bought from Jake.....do it once the right way...

Can you say 103mm Nickies..... wub.gif I have to say though, the case work is not too bad up to 80mm..

Go for it...herb

Posted by: DNHunt Dec 14 2004, 07:48 AM

Mike Why 94mm and not 96nn. I understand your idea about the longer stroke. But 96 is a real tried and true bore. Jakes done a bunch of these and he's said he likes 96 X 78. Get Charles to change to 96

Building the kit Jake put together was really fun. If I ever win the lottery I think I'd just stay home and assemble Jakes kits.

There are certainly things to work out. Valve train geometry is tedious. Deck height is kind of tedious too as I kept rechecking it. It sure helped having Jake looking over my shoulder so to speak. The numbers never come out just exactly the same so I could bounce them off him and he let me know if they were in the ball park. It kind of reminded me of labs. There was always a little variability in the numbers.

Plan on fabbing or buying some tools. You'll need to CC your heads, be able to clamp your cylinders to the case and measure deck height, and measure valve opening and closing for valve train geometry.

Dave

Dave

Posted by: Jake Raby Dec 14 2004, 08:56 AM

All those special tools will be for sale soon- Made just for the Type IV engine!

Hell with the kits you'll have a choice to buy or rent a COMPLETE tool kit to do the job yourself! I'm talkin every tool!

As far as the 71x102 goes I have several combos for it, and have built them, BUT There is NOTHING like stroke!

That stock 2.0 rod journal should be avoided at ALL costs!

Posted by: Joe Ricard Dec 14 2004, 11:33 AM

Damn, what decisions I am faced with. Pay off the house of finance a Raby kit. headbang.gif How to talk wife into another motor idea.gif

Posted by: Bleyseng Dec 14 2004, 12:43 PM

Why avoid the stock 2.0l rod journal??

Geoff

Posted by: Dave_Darling Dec 14 2004, 01:45 PM

Because the Bug rods are cheaper and easier to get. The extra width appears to not be necessary, and the only really high-quality Type IV rods are priced like they were made of gold and platinum. (E.g., Carillos.) You can get some really stout Bug rods for relatively cheap--see some of the earlier posts.

Since you're having the rod journals completely re-worked anyway, why not make them the correct size to work with the less-expensive rods?

--DD

Posted by: cnavarro Dec 14 2004, 02:45 PM

Mike,

Go with the 96s if you're going to stroke it. I can always try to return the 94 pistons in exchange for the 96 KBs. Drop me an email so we can be on the same page before I send out anything to be plated :-)

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

Posted by: Jake Raby Dec 14 2004, 02:51 PM

The stock 2.0 journal on anything more than stock creates a situation where you MUST retain a stock 2.0 rod. There are NO rods other than Pauter (suck) and Carrillo($$) that will work on the 2.0 journal! Using the 2.0 journal puts a whole new list of challenges in the assemblers list of hurdles.

The 2.0 rod is 800 grams, too short and has weak bolts. The 2.0 journals also have no possibility of using a tri metal bearing because nothing is produced for them by Clevite thats better than stock.

The 2" Chevy or 2.165" TI journal is the best choice, especially the TI because it makes for a stronger crank due to less overlap from throw to throw than the stock 2.0 or the 2" Chevy

We only use 2" Chevy on cranks larger than 80mm, and only the 2.0 crank journal on 2056 engines and low performance applications, or where the rules say we have to keep them (Damn SCCA)

The TI journal is the BEST journal on the planet for these engines in every meaining of the word- From weight to ratio, to efficiency..

Posted by: Bleyseng Dec 14 2004, 04:25 PM

Well hell, I was thinking of using the stock rods with 103's as the bottom end only has 10-12k on it. Would like to make good power to 6000-6500 rpms as the crank is CW.

Geoff

Posted by: Eric_Shea Dec 14 2004, 04:32 PM

I'm telling your wife. cool_shades.gif

Posted by: Mueller Dec 14 2004, 04:39 PM

QUOTE(Eric_Shea @ Dec 14 2004, 03:32 PM)
I'm telling your wife. cool_shades.gif

hahaha...I should probebly delete this thread in case she figures out how to visit the site....

Charles...e-mail sent wacko.gif

Posted by: Eric_Shea Dec 14 2004, 05:25 PM

Found this in a local paper... I think you're in trouble Mike huh.gif


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Posted by: Mueller Dec 14 2004, 05:44 PM

luckly the ad didn't mention me accidently wishing her Happy Birthday last Sunday when it really is tommorow....what can I say?, I was tired smile.gif

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