2109cc turbo build...

[Volky]

Hi to all,

I am recently upgrading my engine to a 2109cc boosted bug.

It has:
94mm A pistons (wasn't planning to go stroker)
76mm crank
CB panchito heads 40x35 61cc
Fk-8 cam
Waiting on CB 5.4 h-beam rods...out of stock

I was shooting for 8.5 comp with .060 deck just using a copper shim on top of the head. The piston sticks out .020. So, all this reading on .040 deck has me wondering if I can go for it and end up with 8.8 comp. On my 1776cc I had .070 from scratch, so I left it like that. I would like to run .050 the highest. Any factors I should be concerned with?

The car will be boosting 10-15psi tops. No strip or drag, just street and going to shows around the island. Will have intercooler and w/m injection.

Thanks,

[chriswillrise]

that cam is too big, youll take forever to build boost because of the overlap.

[Chip Birks]

That cam is extremely turbo proven, and loved by many vw turbo users. You are right in a way though, it will want to rev. Almost every turbo motor I've run has had fk8 or larger type cams. The ones with less than that and tiny turbos were definitely the meh combos. I'm pretty happy waiting a second or two for some turbo spool and a little rpm. It gives me a second to tighten my grip on the steering wheel before things get exciting

[Volky]

Chip,

So go with the fk-8, what's your opinion on the deck height being .040. What deck are you running?

Thanks,

[Chip Birks]

I have run .040 before. It worked just fine. I think mine is at .05 now. Still works just fine. I can't say for sure on the fk-8. But if I had it, I would definitely run it. It suits my driving style though.

[Volky]

Chip,

Thanks for the quick reply.

On my install .040 yields an 8.8 CR, .050 yields 8.6 and .060 is 8.3 which was my initial target. Since I didn't want to shim and use spacer why not go .040 with the .060 cyl shim and call it quits. So, I can run the 8.8 CR down the road with the .040 DH and the valves won't touch?

If so, I'll just drop the .060 copper shim.

[Chip Birks]

Valve clearance is something you will need to verify on your own. Too many variables there.

[Volky]

Yeah, I thought so...

Thanks.

[chriswillrise]

That cam is extremely turbo proven, and loved by many vw turbo users. You are right in a way though, it will want to rev. Almost every turbo motor I've run has had fk8 or larger type cams. The ones with less than that and tiny turbos were definitely the meh combos. I'm pretty happy waiting a second or two for some turbo spool and a little rpm. It gives me a second to tighten my grip on the steering wheel before things get exciting

We must of set up my buddys car wrong then, we basically could get more that 5lbs in 1st and 2nd gear with that cam. we just put in a ron lummus cam which was much smaller and we can hit our boost target

[dragvw2180]

Like Chip I like the FK8 , enough that we put it in my sons car. We opted for 8.2 compression , has a bigger tuning window than the higher compression . My personal street turbo engine has a FK10 , drives like a stock bug until I roll onto the throttle then it turns into a monster, LOL. I do like copper head gaskets and I do recommend them . Mike

[Volky]

Hi to all,

I sent the rotating parts for balancing...can't wait to get them back to start the cam degree and rocker geometry setup.

I was thinking of putting the ACE copperhead disc instead of the normal disc I got at home. I took off a 6 puck which messed up the flywheel. I had it resurfaced yesterday. Car will be street only running 15 psi tops.

thanks,

[Chip Birks]

You might push it with the copperhead. I ran one with 180 NA hp, worked great, tried again with probably 250whp and a stage 2 and it would drive through it as soon as boost came on. I have a Diamondback now, it holds pretty well with my stage 3 pp.

[Volky]

Hi,

I have been fiddling around with the cam lift of the FK-8 which states .383 lift and with 1.4 ratio rockers comes out to .536 allegedly. When testing I get .566 lift no matter what I do.

Anyone know what the problem is?

I want to finish the rocker geometry but I this is confusing me since total lift should of been .536 or am I incorrect?

Thanks,

[risk]

Maybe the 1.4 rocker is more like 1.47 ? You could try to measure both sides of the rocker and calculate the actual ratio, but it wouldn't be dead on.

[Volky]

Risk,

I'll see how to do it.

Thanks,