does anyone know if the heads are identical in flow rate and design when comparing the evo 8 JDM to the evo 8 USDM?

 

If I were to bet $10,000 that they are the same..do you think that I would win, Tom? Wish that I could tell you though. I have a USDM head on my shelf and a JDM head on my engine. However, I haven't had them side-by-side on the bench. Sorry, buddy.

 

damn.. you have them both though lol. thats more then most people towards the subject lol.

i think they are the same, but just wanted some reassurance. i am gonna have to confirm it with an egt gauge.

 

Yours is an interesting question. I always just ASSUMED that Evo long blocks per se were identical across the board for the different world market versions, that is JDM, USDM, Euro Market, Latin American versions, Asian Market, and etc., for any given model within each respective generation. That is, for example, all Evo VIII's have a "world head". But that was just my assumption. I just always figured that the actual cylinder head design and casting was the same across the board.

 

Tom, one thing you have to keep in mind about the evo VIII heads is core shift... that in itself will effect VE and EGT alone... we all know how prone evo VIII heads were to core shift.

 

Evo VIII heads showed up on a lot of non Mitsu vehicles and were not cast by Mitsu from what I can tell.

Aaron

 

My evo 9 head had a lot of core shift on it too.

My stock Evo 8 head flowed 220cfm with stock valve @ 0.400" lift.

 

Probably should spend more time finishing tunes and less time with trivial things like this actually

 

I am sure he is wondering so he can finish a build for a customer. I know he has a motor being put together and why not ask to see if anyone knows and if the customer would want one he can get one for the motor. And Tom I would say there about identical. I know when I had my jdm motor for my talon I had 2 heads done and they were idential in flow rates. I can see the 2 evo heads being the same way.

 

Who would shell the extra cash for a jdm head instead of a ported one?

 

If the flow rates are better then a usdm one, it doesn't matter. When you keep the stock angles which possibly flow better then the usdm and clean them up and smooth out the casting it will flow just as good if not better being the head was designed. It is like taking a 2g dsm head and putting it on a 1g car. Ported 1g head is great, but a ported 2g head being it is better flowing performs better. Ask Curt Brown about that and how it works he can explain it better then I can.

 

i have spent all day yesterday tuning cars and all this entire week.. i dedicate myself to tuning these cars. I even tune them Saturday and Sunday..

your response is not necessary. and this information is for a customer. yes you should feel bad now. that was an extremely rude response on your behalf not knowing why i need the information and not knowing the work load i have over here..

and yes i will be tuning AGAIN this entire weekend.. now if that's not dedication then what is?

 

im not sure you tell me? because no ones trying to buy a jdm head here..

 

ok thanks Aaron.. that answers my question pretty much.

and thanks for the others as well who posted good info.

 

Oh cmon Tom...

If you get offended by stuff like this you're in the wrong industry...