Cylinder Head Conversion

[madaboutmotors]

Hi, I have a 1998 Galant 2.0GLS and after doing some research I'm planning on converting the cylinder head from single cam to a twin cam. I have bought an Evo 4 twin cam cylinder head which has been rebuild, I am just wondering what other parts I will need. I know I will need a new head gasket set, cam belt and possibly tensioners but just want to check if there is anything else that will need changing like oil pumps or injectors etc.

Thanks for your help in advance

[Davezj]

is the compression ratio the same on the 2.0L gls galant engine and the 2.0L evo 4 engine, due to the evo 4 engine being turbo charged a turboed engine is usually lower compession ratio. a lower compression ration is needed for a turboed engine to reduce the possibility of pre detonation (knock) i think. so if you run low compression with no turbo i think it will run like a dog.
i am not sure if it is the size of the cylinder head volume that dictates the compression ratio or not.

but i always thought it was like this,
the compression ratio was the volume of the space in the cylinder head with the piston at TDC verses the volume of the cylinder head and the full cylinder volume., expressed as a ratio (e.g. 10:1 where the cylinder volume is 10 times the head volume at TDC), which why it is called a compression ratio but could be wrong, that is just what i had in my head. as the reason.

http://en.wikipedia.org/wiki/Compression_ratio

i was correct.

[orionn2o]

there may a few things to investigate.

Injectors on the evo 4 will be 430cc ish which will run rich if you are sticking with existing engine management. Also the cam sensor maybe different as there are now 2? Does the GLS engine run wasted spark? The evo does so you may need check that. are you planning to run it turbo'd?

[madaboutmotors]

ok thanks, will have to check the compression ratios between the two engines. I hadn't thought about the cam sensors, and I think that the GLS does not run wasted spark, but will double check. I was not planning on going down the turbo'd route just yet, was just going to leave it as DOHC N/A

[Davezj]

to be honest, you might find it easier to transplant a full engine and ECUand sensors, not sure if you will have a drive shaft and prop shaft issue doing this, but it is more than likely.

[Subaru ETA]

Agreed. You would prob be better off sourcing a complete engine, looms and ECU.

[madaboutmotors]

after doing some more research i have found that the galant has a compression ratio of 7.8/1 and the evo 4 engine has a compression ratio of 8.8:1. I have looked at the price of a whole engine, but just thought that because the blocks have the same code I was hoping it would be possible to do a conversion as it would save me money. I have found this website which tells me what timing components are different http://projectzerog.com/sohc-dohc.shtml and shows that it has been done

[lancerevo3]

i hope you current engine is at the correct side of the engine bay for the evo head

[madaboutmotors]

yes they are the same way round, the cambelt is on the left of the engine and the left of the cylinder head