ironhead 3.4 pistons

[GPXSS]

Yes, the 93-95 Camaro 3.4...


you'll have to do alot of chamber work to get that compresison down, tuning would suck that high too... If you go that route (3.4 pistons) then atleast use the .060 gaskets to take it down a little..


3.4 RWD pistons in a 3400 and the .040 gaskets it's 13.9:1
3.4 RWD pistons in a 3400 and the .060 gaskets it's 12.9:1
3.4 RWD pistons in a 3400 and the .045 ROL gaskets: 13.64:1

with the 3100 GPXSS is talking about he's got 11.88:1, that's not bad at all...

my 3100 is .060 over so that raises the overall CR. GPSE3400 has done this with a 3400, im hoping he will chime in here. I should also add that we both are running long duration cams which will bring down the overall cranking pressure.

Normally I would agree with you SuperDave to increase headgasket height to drop compression, but you do not want .060" clearance between the piston and head. The further away you go, actually the more chance you have for detonation.. this is why I suggest using the .040 gasket.

[geldartb]

did he use the rods from the ironhead 3.4 or from his 3400. the only reason im asking is i found a set of ironhead pistons and they come fully assembled. just wanting to know if its possible to use the rods or worth it.

[Superdave]

did he use the rods from the ironhead 3.4 or from his 3400. the only reason im asking is i found a set of ironhead pistons and they come fully assembled. just wanting to know if its possible to use the rods or worth it.

Rods are probably the same either way...

[geldartb]

yeah i kinda figured that but youknow how they like to change random things. oh well ill find out when they get here this week.

[izayn]

Correct me if I'm wrong but,
The setup that is being disccused is the 3400 engine no mods with the Iron head pistons.


What would happen if you use the 3500 Top end swap ( Is it simpler , more plug and play, any shaving, etc....)

[geldartb]

for the now the setup were talking about is stock, until i decide on a cam.

the overall CR would be lower seen as how the combustion chamber is bigger. you know when you drope a 3500 tope end on a 3400 bottom end you get lower CR.

heres a quick one done with the CR calc with a completely stock 3400, with opening up the combust chamber 10cc it brings it down to 11.5-1
Bore 3.622"
Stroke 3.307"
Head Gasket Bore 3.75"
Head Gasket Compressed Thickness .040"
Combustion Chamber Volume 36.0 cc
Piston Dome Volume 8.0 cc
Piston Deck Clearance .0095"
Displacement 3349 cc
Calculated Compression Ratio 11.56:1

[Superdave]

Correct me if I'm wrong but,
The setup that is being disccused is the 3400 engine no mods with the Iron head pistons.


What would happen if you use the 3500 Top end swap ( Is it simpler , more plug and play, any shaving, etc....)

Well, the 3500 has bigger combustion chambers so it would help out the SCR a little.. and flows TONS more air...


That was actually my original plan when i started building the current engine for my car.. i just ended up going all 3500 though.

[geldartb]

ok im basically aiming for a 11.5:1 CR with the setup thats with gaining 10cc on the combust chamber. would it be easier to tune the setup below which is basically the same but adds a couple cc's to the combust chamber to bring the CR down to 11.1:1.

now im looking for a good cam to make the most out of this setup. im looking for good low end torque and enough tope end so it doesnt fall on its face before 6k.

Bore 3.622"
Stroke 3.307"
Head Gasket Bore 3.75"
Head Gasket Compressed Thickness .040"
Combustion Chamber Volume 38 cc
Piston Dome Volume 8 cc
Piston Deck Clearance .0095"
Displacement 3349 cc
Calculated Compression Ratio 11.18:1

[GPXSS]

Call whatever cam company you are buying from and tell them exactly what you have and what you are doing. They will tell you what cam to go with.

If you are going high compression then you need a high duration cam to help bring down the cranking pressure.

[geldartb]

thanks for the advice on the cam. ben said he had a good profile that fit what i was looking for.