4g61t.org

I've just had a thought, would this work....

4g67 block rebored with 4g61 pistons, 4g61 head and a Evo 1-3 turbo?

Do u guys think this will work and what benefits would this have?

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playing with the same colt since 2002 and still going.....

Probably the same benfits you would get from hanging the EVO 1-3 turbo on the 4g67 engine and taking the money saved from machining to buy tuning equipment.

Agreed, or just swapping in a 2.0 for that matter.

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91 GSX - 511fwhp and 352 lb/ft 25psi 110 octane, 7.68 @ 95.9mph 1/8th 21psi 91 octane, 11.93 @ 112.9mph, 117.7mph best trap speed, 20psi 91 octane
98 Volvo S70 T5 - DD

http://www.facebook.com/captaintonus

4g63's are not about in the uk like they are in the us, I just wondered what cc that would make it Manley?

As for costs the rebore would not be expensive tbh.

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playing with the same colt since 2002 and still going.....

No not expensive but still it could be money spent in other areas. You could buy a wideband oxygen sensor for the cost of boring an engine alone. What is the CR of the 4g67 9:1? Buy a set of OE turbo 4g63 cams from anyone on this board and you would be able to easily hit 200whp with an EVO 1-3 small 16g on the stock 4g67 bottom end.

That sounds like a good plan

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playing with the same colt since 2002 and still going.....

Just a thought but would I not need to lower the compression ratio down from 9:1 so I can run a normal amount of boost?

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playing with the same colt since 2002 and still going.....

Nope. 9:1 is great for boost. Not too high to have to worry about detonation and high enough to spool the snot out of a turbo.

I'm running 10:1 pistons in my 4g61 and 12psi on a small 16g. As long as you run some kind of ECU you can tune, it works fine.

Also, I didn't notice any decrease in turbo lag from going higher compression. A local shop took a turbo Honda from 8:1 to 13:1 and the datalogs on the dyno showed the exact same spool time. The way he explained it to me, changing the displacement means more airflow through the engine which spools a turbo faster. Only upping the compression, doesn't change the displacement hence same spool times. All it does is squeeze the same amount of air tighter to make a little more power from the same amount of air.

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'89 Colt GT w/bigger than stock turbo
'91 Talon AWD w/bigger than stock turbo
'05 Dodge diesel w/bigger than stock turbo

Huh. I thought increasing the CR would create more energy in the exhaust and thus spin the spin faster/sooner. But any energy present in the exhaust charge after ignition would be proportional to the amount of air and fuel burnt in the combustion chamber. Makes sense, and I can't argue with a datalog. LOL

There are a lot of arguments that having higher compression makes the exhaust more "efficient", which means there is less heat in it, which means it would actually spool a turbo slower, or just as fast as it did before. It's difficult to differentiate between a car with "more low-end torque" and a car with "a faster-spooling turbo", ya know what I mean? I don't know how much truth there is to any of this, this is just crap you overhear throughout the years when "smart" people are talking.

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91 GSX - 511fwhp and 352 lb/ft 25psi 110 octane, 7.68 @ 95.9mph 1/8th 21psi 91 octane, 11.93 @ 112.9mph, 117.7mph best trap speed, 20psi 91 octane
98 Volvo S70 T5 - DD

http://www.facebook.com/captaintonus

Oh I know man. Quite often there are theories and logical processes that people try to apply to engines that just do not happen the way they look on paper. All that matters is the effing turbo spins and magic happens. lol

Yeah, I thought the same thing too. I wanted 10:1 pistons to try and make it more efficient for better mileage. I was hoping it would spool faster too. When my friend told me his experience with it I thought wow, it makes sense but isn't what I expected. Now that I have a running 10:1 car with nothing else changed besides the pistons, my results are that it spools just like before.

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'89 Colt GT w/bigger than stock turbo
'91 Talon AWD w/bigger than stock turbo
'05 Dodge diesel w/bigger than stock turbo

So throw in some E85, crank up the boost, and have a car that makes a lot of power on a smaller turbo and has an awesome powerband.

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91 GSX - 511fwhp and 352 lb/ft 25psi 110 octane, 7.68 @ 95.9mph 1/8th 21psi 91 octane, 11.93 @ 112.9mph, 117.7mph best trap speed, 20psi 91 octane
98 Volvo S70 T5 - DD

http://www.facebook.com/captaintonus

I wonder if they have E85 as cheap as we do without the us-government subsidies.

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