Race engine build advice

[TargaT]

Hi Folks, I am soliciting advice for a 2 litre race engine build. The main goal is reasonable power (120-130 HP) and reliability. I have 914 race car I purchased a while back which came wisth a "fresh" rebuild spare that I installed and failed after some run in time. (rod bearing) Started the disassembly last night and this engine was destined for failure, so many things done wrong. This is my first flat 4 but have done a 2.4 six in the past. I'd like to know what are the key performance and reliability upgrades I should do. At the same time reutilizing what is good in the two motors I have.
What I know I have:
- 40mm Dells
- a Webcam in both engines I believe, specs TBD
- a freshs set of heads with HP springs but stock rockers
- pistons seem to be low compression (dished) 3 of one type 1 different, looks like rings may have been installed upside down
- cylinders, 3 of 1 type, 1 different. Appears they were not honed before installation of new rings
- high volume oil pump but is now trash,
- crank probably has one bad journa

Once I finish the tear down of this engine I will do the same on the other and see what is salvageable. I am tempted ot move for a new set of cylinders and pistons 96mm. What brands would you recommend and what compression. Or should I just bore the sleeves I have? What about valve train upgrades? connecting rods? cylinder studs, push rods etc. anything that is not outrageous cost. I look forward to your recommendations and will post my progress.

Thanks, Joe

PS this car is too be run in Vintage class.

[Dave at Pelican Parts]

Torque plate hone the existing cylinders out to 96mm, if legal for your class(es). Cylinders that have been heat-cycled a zillion times should be more stable than new ones. Plus very old ones seem to be higher quality than much of what we get new these days.

The heads are where the real power is in these engines. They can also be on the fragile side. At the very least, having them gone through by someone who knows what they are doing is a must. Len Hoffman at HAM Inc knows Type IV heads; he can do anything you might need done to a 914 head.

For pistons, JE makes good sets. AA P&C sets have attractive pricing, but the quality on them has been pretty spotty in the past. Particularly, I have heard, on their cylinders.

The stock rockers can be lightened without weakening them. The aftermarket "ratio rockers" are generally not intended for reliable engines, but rather for quarter-mile engines. People have addressed that to at least some extent with add-on oiling systems, but I don't have any information on how well that works.

A lot of people go with chro-moly pushrods. You use different valve lash specs when you use those.

The stock rods are OK for moderate power levels. There are H-beam ones you can pick up that are stronger, but I'm not sure how much you need them at 120-140 HP.

Compression ratio is determined by a lot of factors, like what kind of gas you can run (and are willing to run), the cam and valves, chamber shape, etc. The stock MILD cam allows for 8.5:1 on what passes for "premium" fuel around here. Wilder cams require more, and higher octane allows more.

Look into the exhaust. That is actually one significant exception to "the power is in the heads". Tangerine Racing (Chris Foley) makes the best, IMHO, and charges like they are the best. They have good mufflers, too (good for sound-restricted tracks or even the street!) and even a heat-exchanger option. European Racing (George Narbel) makes effective headers that are less costly, as does Triad West. The Kerry Hunter headers may be available (I had heard rumors they were not for a while) and are the least expensive and are generally less effective than the more expensive options.

The good news is that your power goals are pretty modest. Going up to 2056cc with a decently-aggressive cam, a little head work (probably stock valve sizes), and the Tangerine exhaust should put you right in there.

Make sure your cooling is up to snuff. Instrument the engine; oil temps and head temps are very good to have a handle on. There's a very good chance an external oil cooler will be required, at least if you drive in hot ambient temps.

Good luck!

--DD

[GeorgeRud]

I seem to remember that Dave Finch in Ohio was a big shot in the 914 racing world back in the day. Also, early Super-Vs were racing with type 4 engines, so some of that engine building talent may still be around.

I would assume that Jake Raby would be another reliable source, but any engine that is really competitive is also a hand granade waiting to explode. Speed costs money, how fast do you want to go?

[Matt Monson]

Originally Posted by GeorgeRud

I seem to remember that Dave Finch in Ohio was a big shot in the 914 racing world back in the day.

He won an FP SCCA national championship in 2005. You could say he came out of retirement to build that car. I provided the front clip and gearbox on that car.

TargaT,
Like Dave said, the real power is made in the heads on the TIV. Get your heads worked by a professional.

[Dave at Pelican Parts]

The FP cars shoot for just a little bit more than 120-140 HP, though. I recall the 1.8s making about 180 HP, with some claiming more and some claiming less; I assume the 2.0 cars were at or over 200 HP.

"Reliable" takes on a different meaning with those power levels. It often means, "Didn't need a 'refreshing' through the whole weekend".

Oh, and "Expense" also takes on a whole new (and quite painful!) meaning when running at those power levels. Lots of work and $$$ to get there and keep it alive.

--DD

[Matt Monson]

Yes, an FP engine is a high strung beast. All the OP needs to do for his goals is use the parts he has on hand, and get a bit of head massaging and he'll be where he wants to be.

[TargaT]

Sorry, haven't checked in for a while as I've been spending time doing research. Connected with DRD Racing (Darren). Not sure if any of you guys have heard of him or his reputation.He has been very helpful so far. Here's what I have on the list so far:
- counterbalanced forged crank (standard stroke)
- Keith Black 96 mm pistons 8.5:1 and new cylinders
- Webcam type 494 cam/lifters
- chromoly push rods
- H beam rods
- High volume oil pump
- Dellorto 40s
- lightened flywheel
- heads have been done with mild porting, heavy duty springs, titanium retainers

Anything I'm missing?

[Dave at Pelican Parts]

Exhaust.

--DD

[Racer Chris]

Originally Posted by TargaT

Sorry, haven't checked in for a while as I've been spending time doing research. Connected with DRD Racing (Darren). Not sure if any of you guys have heard of him or his reputation.He has been very helpful so far. Here's what I have on the list so far:
- counterbalanced forged crank (standard stroke)
- Keith Black 96 mm pistons 8.5:1 and new cylinders
- Webcam type 494 cam/lifters
- chromoly push rods
- H beam rods
- High volume oil pump
- Dellorto 40s
- lightened flywheel
- heads have been done with mild porting, heavy duty springs, titanium retainers

Anything I'm missing?

JE Pistons are a better choice for an engine which will spend most of its time in the upper rpm range. Have your cylinders honed to match them.
Get them with a mild dome and up the compression to 9.5:1

Use a Web 86A camshaft and prep the engine to redline above 6000 rpm.
With good intake and exhaust flow you'll be able to use it. RPM = HP
You could easily reach 140 hp with a reliable, and very driveable engine.

Get some big venturis for the Dellortos: 34-36mm.

Use good stainless valves. Change the exhaust stems to 8mm.

Getting the engine to breathe better is just as important to making it rev higher as balance work and lightening.
Oh, and don't bother with the counterbalanced crank.

[TargaT]

Hi Chris, thanks for the great advice. Regarding the crankshaft, I would have to recondition my original so I am about halfway to the cost of a counterbalanced unit. So for about an extra $250 is it worth it? I heard the counterbalanced are quite a bit heavier?
I guess, I could use the savings toward upgrading the pistons?

Thanks,

[Racer Chris]

Originally Posted by TargaT

Hi Chris, thanks for the great advice. Regarding the crankshaft, I would have to recondition my original so I am about halfway to the cost of a counterbalanced unit. So for about an extra $250 is it worth it? I heard the counterbalanced are quite a bit heavier?
I guess, I could use the savings toward upgrading the pistons?

Thanks,

Adding counterbalance weights actually increases the risk of crankshaft failure.
They also add back the weight you paid to have removed from the flywheel.
There is minimal benefit at the rpm you'll be running so I would spend the $250 on pistons instead.
IIRC, K&B pistons are cast. JE are forged - much better for severe use.

[mrhyde]

I see you're in Burlington ...I'm up in cambridge and am in the process of building my engine now ( 2316cc ). As well as a finishing a full ground up resto on my 72 914...

I would suggest contacting Mark Henry on here or the 914world forum for heads.. He did the heads for mine and has been building engines for years... Also easier than shipping to/from the states.... He might be able to help ya out... As for exhaust. Racer Chris is being modest. His exhaust setup is basically the best you can get from all the research I've done. I have one of his setups waiting to go onto my car..
Also, there is a shop in Toronto that can do balancing for our engines.


You planning on running at Mosport ???

[yeahmag]

The 494 will not get you were you want to be. The 86a will get you there depending on your heads and exhaust.

[TargaT]

My spare crank is currently getting reconditioned. The one that spun is apparently cracked so it's trash. It looks like the case I have was fully prepped including new galley plugs before failure. Due to the catastrophic nature of the failure I'm assuming all the case plugs should come out for a thorough cleaning and replace with threaded plugs while I'm at it. I've found a lot of info on the web on this topic but not one clear article to I could simply hand to my machine shop. I heard Raby had a complete article but it's nowhere to be found?
Also should I simply bore my original Mahle's to 96mm and use JEs or use new aftermarket cylinders? the cost would be similar.

Thanks, Joe

[Racer Chris]

If you have a machinist prepared to bore/hone the cylinders I would use the originals.