I am curious what head gaskets i should run on a WRX with and STI shortblock in it. Ive been suggested to use either factory gaskets or cometic gaskets. Im just kinda curious what the differences are?? I just ordered ARP head studs to hold everything together as well.
You're going to need to run a custom cometic headgasket to get the right compression ratio. I think crawford and Axis racing both stock the proper gasket, I think the compressed height on the gasket is 0.040 but you should check that before you order. Matt
I just ordered them from gruppe-s for $140 shipped. They have a compressed height of 0.040"!! Thanks for the help Matt, keep an eye out i may need some more help later!!
i've heard from SS that the higher compression when you do the swap is quite fun, and helps spool a lot faster, like 21lbs at 3300rpms on a 20g. i plan on doing the same swap when i get my next suby and plan on keeping the higher compression since i dont really care about making insane power gains just somehting fast and fun. Alex
the higher compresion usally leads to limited amounts of boost, the higher the compression the less boost you can run on pump gas.
Yeah and i want it to be very driveable, reliable, make some pretty nice power, and be very happy on pump gas. Hopefully this setup will be all of these things!
yowza, that will be a dead sexy car you will have, what sorta power numbers are you looking at? 330-360whp?
you askin me or jonnyboy? as for me, yes i will be doing the swap, not a shop, as far as myself, hopefully i will have help. Alex
Exactly, im hoping for something in the mid to high 300's! And I also will be doing the swap myself. Its way to expensive to go the other route.
Also i like the whole methanol idea! And bugeyes get two boost maps with ecutek, so ive been kinda tossing around like a 19psi street map with a high boost map (maybe 25psi or so) w/methanol injection. I dunno about all that tho. Ill take things a step at a time, lol.
this is something i what to do in the future as well. what is the total cost involed, not counting labor?
Probably around 1500 bucks, maybe a little more or a little less. Anyone know what the stock STI head gasket compressed thickness is?? I was talking to Scott today and he was saying that using the factory STI head gasket raises the compression to around 9.0:1 while using the factory WRX head gasket maintains around 8.5:1. If anyone knows that spec please let me know!!!
I used the stock 2.5rs gaskets and new stock head bolts and have not had any issues running 23 psi for 25k miles. They are slightly thicker than the stock STI gaskets. You also cannot use the stock WRX gaskets because the bore is larger and the gasket will be in the combustion chamber. I have done the swap once and helped with 2 others. If you ever need a hand drop me a pm. Mike K
I hope to just do it in a few days after work, i work at a dealership so any tool needed will be available.
The right tools are key. So is having all the parts available. It took me 2 weeks due to having to order parts but actual work time was probably more like 20-25 hours. I also did it by myself on ramps in my garage. Having a lift and an extra set of hands would have helped. There is an engine rebuild gasket kit that will have all the the gaskets and seals that you will need. I would suggest picking one of those up.
What else will i need (seals and gaskets)?? I dont wanna get everything if i dont have to, know what i mean. But i would like to hit on many of the major ones. I know of the timing belt and of course the head gaskets. Any other ones that will most likely be necessary?? Or if that seal kit is pretty cheap ill just go ahead and get it, how much did you pay for it?? LiquidForce...What kind of clutch are you running?? Im leaning strongly towards a six puck sprung hub clutch. Genya says he loves his and that it is very driveable almost like stock. Also have you had any gearset problems?? I am pretty sure my gearset is in fairly good condition, i have never beaten on the gearbox hard at all. I just kinda want to make sure it will be ok holding the power or else ill need to take that into consideration in my budget if it decides to crap out on me. Thanks for all the input everyone!! Ill try to keep everyone posted on the progress!
I run the stock wrx clutch and flywheel. When I upgrade the tranny I'll go with a more aggressive clutch. Right now I prefer the clutch to slip instead of my transmission breaking. The engine rebuild gasket kit I think cost me around 150. It has everything you need. I would definatley advise getting it.