2084 Turbo Build

[buguy]

I saw an engine Paradise built with their build sheet on it. It showed a deck of .089". Those guys surely know their stuff. I don't know anything about the specifics of the engine, but if they aren't scared of some deck, i wouldn't be either. 11cc's is quite a bit to get out of a head.

[kangaboy]

Any chance you could dig that build sheet up? Curious if it was for a drag strip car, or if they still intended to use it on the street.

[Clonebug]

Just for giggles get a couple feeler gauges and eyeball the difference between say .040 and .060" .020" isn't much and I just can't see how it would make or break an engine build.
Most those Samba people are on a 6 year engine build and some of the ones that get their engine running end up having issues in the first 1000 miles or less.
Don't get hung up on the small stuff like they are......get your bearing tolerances set good and make sure you have decent clearances.....and run it.
A turbo is going to give you sooo much more power that a larger deck won't make a big enough difference. The tune and IAT's will be more important. If you need more power...turn up the boost.........

[buguy]

Sorry brother but i don't have a clue where i saw that at. I agree with others here. With your time running out, i think running more deck is your best option. Unshrouding your valves would be a good idea, but your not going to get the cc's you need just doing that. Getting the pistons dished would be good too, but finding someone to do that very quickly would be tough.
I don't know how important your track day is, but could you build it as is and run race gas, then deal with it after that?
I personally am running 9:1 on E85 and have experienced knock. My fuel was about a point leaner than my target though. I have tuned the knock out up to 22.8 psi so far, but it has taken more fuel than i expected it to, and now I'm maxxed out on the new 1000cc injectors i just put in 3 weeks ago.
Maybe you could shim the barrels with an .040" copper head gasket in mind to get you where you want to be. That way you could always change it a bit with a smaller or larger copper gasket fairly easily?

[buguy]

I should add just for a reference, i made 195hp on 13 psi @ 4000 rpm (let off early on my first ever dyno pull), 221hp/243tq on 18 psi @5300 rpm, and 242hp/260tq on 20 psi @ 5400 rpm. These runs it was hammering away with detonation (i thought it was my BOV opening under a load). Not sure what it would do now with the proper amount of fuel and lowering the timing, but this will give you an idea.
2054cc
Web 163 cam .505" lift 250@50 duration
35x40 cheap AA heads
9:1 on E85
TD04-19t turbo
1 3/8" header and no muffler
Tons and tons of low end, instant boost, and i seem to always shift at 5800 rpm, so that must be about where it runs out.
I set the boost for 18 psi and these were my last 3 runs:

[kangaboy]

So after taking everyone's replies into consideration, I've decided to do a little of both options, and open the heads by removing as much material as I feel comfortable doing (>5cc's), and then run the bigger deck height (~0.085"). I figured with this approach, I wouldn't really be doing anything irreversible (as long as I don't butcher the heads), and if it ends up being a slow turd down low (off boost), I can always just take the heads off and send them to someone to find those extra cc's that I need to allow my deck to come back down to 0.040-0.050". Again, with all the comments you guys have given, I'm sure the big deck will be just fine.
Also, with the new path forward, I'm going to have to opt out of the races this weekend. I told myself at the beginning of the build "don't cut corners to meet a deadline," and I intend to stick to that. Truth be told, we're going to get this motor together and then break it in and prolly bust the stock T1 transmission on the first big pull.
Stay tuned for combustion chamber pictures...

[buguy]

Good luck brother. My trans held a bunch of power. Axles, however, not so much.

[madmike]

Races? wouldn't happen to be our BugRun in Martin Michigan? this weekend too,,I to am opting out ,, I may be there, just bugless
Yepper break it in right K.Boy
Stock trans worked for me till this year(4-5yrs) I still drive it but forget 'speed shifting' on 2nd & 3rd

[kangaboy]

Nah, not the BugRun. Unfortunately we don't get any VW races down here in STL. Our local track sponsors the Import Face-Off event twice a year, and we have around 6 air-cooled VWs that show up though. We have had enough the last two races to have our own class, but the guys winning are usually low 12s. I'm hoping I'll be able to keep up with them next time

[madmike]

STL? ,, with you'r combo 12's should come 'easy'

[kangaboy]

St. Louis, MO. The racetrack is actually located right across the river in Illinois, but it's close enough to St. Louis city to be considered one in the same.

I spent some time last night opening up the chambers on one of the heads. I'm going to re-cc it after work today and see if I am anywhere near the 60cc's that I'm looking for, and they try and copy the work over to the other head. I attacked mostly the spark plug side of the exhaust port, which is where several folks said would cause the least impact in regards to flow. I tried to stay out of the squish area, and left the step alone. I didn't have a cylinder in hand, but if I need to gain any more combustion area, I'll place a cylinder down in the head and see how much more room I can get on the exhaust port side before getting into cylinder landing territory.



Jim also took the time and machined down two of the cylinders 0.005" to give us an even cylinder deck height of 0.023" on all 4 cylinders. That deck, plus the 0.016" step in the heads puts us at ~0.039". If I get to 60cc chambers, that will give me a compression ratio of 7.95:1 with a 0.050" shim under each cylinder (all the same with 58cc chambers gives a 8.14:1 ratio).



Also, a quick 0.02" shave of the rocker blocks gave a much better (centered) swipe pattern as compared to when we initially bolted it together. I'm hoping the valves and their respective guide appreciate this and give a few more miles of use.



WE'RE GETTING CLOSE TO A FINISHED LONG BLOCK!!!

[buguy]

When i did mine i used copper head gaskets. That way i can more easily change the compression later if i need to. Just a thought.

[madmike]

Purdy close to a 'Semi Hemi' My set of Hemi's are at 80cc Just FYI

[kangaboy]

When i did mine i used copper head gaskets. That way i can more easily change the compression later if i need to. Just a thought.

The only difference is the removal of the wrist pin to take the cylinder off, no? Always figured it was better to keep the spacers on the case side of the cylinders to reduce the amount of sealing surfaces in the heads. With a copper shim in the heads, it effectively doubles the sealing surface area in the combustion areas.
The heads look super shiny like I cut a lot out of them...but in reality I only cut out behind the spark plug side of the exhaust port. After cutting away on all 4 combustion chambers last night, it looks like we're sitting at ~58cc chambers. I'm going to do a little more unshrouding and blending to try and get those last two cc's, and then order some 0.050" barrel shims and get this thing bolted together.

[buguy]

I don't know which is better. I personally don't even take the pistons off when i pull cylinders. I just feel if i can simply pull the head and add or subtract the copper shim, it doesn't get much easier than that.