4g61t.org

wonder what the cr would be if you put the 12 valve head on with 8valved dished pistons? would the dish be enough for the valves or would the pistons need reliefs for the valves?

I know it wold make the cr lower but might be a good starting point for turbo 1.5?

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RIP- '92 Colt 200E, 12valve 4G15, 5spd.

'89 Colt 200E, stock 8valve 4G15, 5spd,

if i am right, you would get a 8.5:1 cr with that combo.

i will have to start to look for pistons to do that, or just keep the 8v.

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Stock Sucks...!!
Mods List:

Custom cold air intake
Iridium Sparks
NGK sparks plugs wires
2" exhaust and moffler
ACCEL Coil
240cc inyectors
52mm TB
K&N filter
Elantra BRAKES ( upgrade )
195/50 R15
2.5" lowering springs
Ate. brake Fluid

I wonder how well the 4g15 would like a turbo with only 8.5cr.

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Had a:
1991 Eagle Summit ES Hatchback - 4g15 12v 5spd
1991 Dodge Colt -4g15 12v 4spd
Have a:
1978 Oldsmobile Cutlass - 468BBO TH350
Round 3:
1990 Dodge Colt-4G63T 5spd

The only problem I see with that is if you decide to get serious with boost your still running stock strength pistons which wont like the extra heat from the turbo. Might as well stay with the stock pistons and stock compression taking the better off-boost response and just keep the pressure below 10psi.

talking about the pistons.........

what would be the highest CR with stock conrods that 4g15 can handle?

12:1 would be too much? 4g15 8v?

I was searching about the conversion in a 12v ( 8v block ) and it suppose to has differents head gasket..... i knew that it was not differents.

now I dont know.

_________________
Stock Sucks...!!
Mods List:

Custom cold air intake
Iridium Sparks
NGK sparks plugs wires
2" exhaust and moffler
ACCEL Coil
240cc inyectors
52mm TB
K&N filter
Elantra BRAKES ( upgrade )
195/50 R15
2.5" lowering springs
Ate. brake Fluid

The 4G15 rods aren't all that strong although they will hand 10-12psi so long as you keep the tuning conservative so as to avoid detonation. It is detonation that causes the most problems and will always break the first weak link in the chain.

I think you'll find that the differences in the HG are to suit the 12v head rather than the block but I could be wrong.