ALFAGTV6.COM

But I always look at my V6 funny, and I've never had a...oh, wait, I do have a headgasket problem. I'll have to stop doing that.

Thanks Grant, I'll be sure to have a chat with my machinist about clearances before I do anything.

Maybe you should try calling Venolia directly. I would think they have some standard piston designs on file for the 2.5l. I had a set of pistons made for a 2l fiat a few years ago, and they were very helpfull.

No need to appologize Zambon, it's very good advice. That's exactly what "normal" people woud do. I would do that too, if the penalty were not so high. And thanks for the heads-up on the casting marks. I'll check with the rules gurus to see whether they look for "port reshaping" ...

Thanks Daniel! that helps a lot.

I'd planned to leave the intake valve sizes alone, and the heads unported for the most part. The Alfa competition code seems to place an unreasonably high penalty on bigger valves and head porting, at least at first glance. I had intended to get a high quality valve-job, some better flowing valves a...

Thanks for the info. You didn't by any chance measure the change in combustion chamber volume, and calculate the new static compression ratio did you? So far the only data I have is Jim K's statement about his 3.0l. The 2.5's lower swept volume should give a lower compression number, but it has a sm...

I've found an old post where Jim K. says that he shaved 1.6mm off of his 3.0 heads to get an 11:1 compression ratio. Does anyone know if this is the upper limit for removing material from the 2.5 head? Has anyone done more? Does it start to have a negative impact on flow and combustion as the chambe...

No, not that head, I already did that! :wink: I have a 2.5L engine in my gtv6 racecar project. I suspect that it has at least one head gasket leak. It seems to be a small one, slightly pressurising the cooling system, but it's a 9 hour tow to the track and I don't want to take any chances, so the he...

Thanks very much Michael and TS_turbo! They are both fantastic links! Very helpfull indeed.

Seriously? Nobody ever flow tested a stock 2.5 head? That's weird, it seems like a good idea to me. I guess I'll try to get it done and post the results in case anybody's curious.

Does anyone have flow numbers for a stock 2.5L head? Also, are the 2.5l intake runners the correct size for the stock 2.5l intake port? I know they're undersized for the 3.0l, but the 2.5l should be correct, right?

Thanks
Graham