Eg hatch, Built B16a, Custom kit, 760whp/460tq, AEM EMS

[boosted hybrid]

Car: Eg hatch

Engine: 84mm sleeved B16a block, Skunk2 Tuner stage 2 cams, Edelbrock Intake manifold, hondata intake manifold gasket, 9:1 b20/vtec pistons (around 7.8~8:1 compression in B16a block)

Mods: Peak boost top mount manifold, t3/t67 H.O .82a/r, 3" dp, 3" exhaust, no cat, precision large front mount intercooler, custom 2.5" charge pipes, tial 44mm wastegate, tial 50mm bov, Kgparts.com 1600cc injectors, aeromotive eliminator pump, sumped fuel tank, -10 a.n feed lines, -8 a.n return lines, aeromotive a1000 fuel pressure regulator, AEM Pro Billet Distributor, MSD Digital 6 ignition, MSD Blaster HVC-II coil, NLR AMS-500 boost controller, AEM EMS

Tuning at 18psi and 34psi on Q16 fuel:



Old set-up ran 10.1~10.2 at 146mph with 60-70whp less power. New set-up broke a stock valve on the first few passes, waiting to get rebuilt. New block has 9~9.5:1 compression pistons and full Manley valvetrain. New set-up should get easily into the high 9's with some seat time.

[Jitu]

Car: Eg hatch

Engine: 84mm sleeved B16a block,9:1 b20/vtec pistons (around 7.8~8:1 compression in B16a block)

When i was deciding on piston for my B16 84MM bore with stock stroke, i wanted effective 9.1 c.r ,
The 9:1 C.R on a b20/vtec piston is with 89MM Stroke, but since i was using 77mm stroke on B16 i went ahead & installed CP 9:7 C.R B20/Vtec piston, My cylinder pressure across is 200 Psi, i know its close to 9:1 but i want to know exactly how much?

[boosted hybrid]

cc your combustion chambers, and take the cc of the piston and put it into a compression calculator and find out exactly how much compression you have.

[Jitu]

Thanks jeff,
whats the correct procedure to c.c combustion chamber, I am using CP 84mm pistons part# SC7017
Bore diameter = 3.307
Compression height = 1.181
Dish Depth = -0.21

& thanks a lot for your replies, you are my inspiration...!

[boosted hybrid]

You need to make a plate that you can inject liquid into the combustion chamber that will simulate the deck surface of the block. Once you have filled the combustion chamber, you dump the liquid out into a measuring cup and see how much liquid was needed to fill it. If you have had no combustion chamber work done, you should be at stock c.c specs. You can find the specs in a Helms manual or on the net.

[SWAPIT]

thanks jeff for postin the graph lost my sheet.car is down right now still waiting on the new block but have everything to put it back together.i going to be driving the car now to so seat time is def. needed.

[boosted hybrid]

You should be able to make some more power with the higher compression on the new pistons. I figured out some stuff with the AEM that will help with traction..

[Jitu]

I went the other way round before opening the cyl head.
like this
Bore 84 MM
Stroke 89 MM
C.R = 9.7 (as per C.P's spec chart 9.7 c.r with 89mm stroke)
B16 head C.C/Cyl 42.70 (Stock which i am using)
Head Gasket thickness 0.02900000 (in) OEM 3 layer
piston dome displacement= _____?

In a compression ratio calculator i put in the above values & for piston dome displacement i randomly put in values till i get resultant c.r of 9.7
-5.68 is the value i found for piston dome displacement which resultant in 9.7 c.r with above spec in a compression ratio calculator.
now i reduced the stroke to 77mm & rest same as above with piston dome displacement of -5.68
the resultant c.r is 8.5:1
Can this result be taken as accurate? I was planning to shave the head to increase c.r to around 9.1 is it worth doing this?
need your inputs.

[boosted hybrid]

I would not bother milling the head. If the compression is that low, just run the engine. There is little to no difference in power between 8.5:1 and 9:1.

[joshuajames]

Could this turbo have made more more?

[boosted hybrid]

Yes, it could have. I could probably have went to 40 psi, and gotten another 30-40whp out of it.

[boosted hybrid]

Update on this car, its running consistent 9.9 @ 149-150 mph at 30 psi of boost (around 700whp). Getting some things figured out and this should be a consistent mid 9 second car.

[SWAPIT]

All our hard work is starting to pay off cant wait til we get the boost to stay up i think the car will go a .6 w/all the power
I just want to thank you for all your help it is greatly appreciated!!

[spoolin turbo s]

is the late spool from the combination of it being 84mm with a b16 crank and the low compression ratio?

[engineer_ek4]

On a side note, I know you stated the car is running 3" exhaust w/o cat, is the exhaust ran under the car in the stock location ? Why I ask is because i want to know if this power level can realistically be achieved with full exhaust and exhaust tip. I am turbocharging my ek4 and the stock exhaust has two 90 deg bends around the gas tank.

[boosted hybrid]

The car has a full 3" exhaust from the downpipe back to the bumper.