Turbo cams in 2.5 DOHC heads?

Heads, valves, pistons, rods, crankshaft, etc...

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All_talk
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Turbo cams in 2.5 DOHC heads?

Post by All_talk »

Hey guys, haven’t been hangin around much lately, work, other projects, hobbies and such… life, you know the story.

Anyway, looking to finally (maybe) do some engine work on my ’91 SS, I’ve held off installing my EJ20G heads due the low compression issue with stock pistons. But last night my Subie buddy down the road offered up a great deal on a set of EJ2.5 DOHC heads, the compression numbers look good with the 49cc chamber, and assuming I can address the water passage, coolant/oil feed & return and cam gear issues I think it looks good.

I’m concerned with running the N/A cam profile in a turbo engine and not getting optimum performance, so two questions:

One, what stock (or aftermarket) turbo specific cams will fit in the 2.5 heads? Will the EJ20G cams work? WRX cams?

Second, does anybody have timing and lift specs on the EJ2.5 DOHC cams? EJ20G cams? WRX cams? Maybe I can run adjustable cam gears and split the duration a little and use the N/A cams?

Gary
No matter how broke I am... I always seem to find two cents.
Matt Monson
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Post by Matt Monson »

http://forums.nasioc.com/forums/showthr ... light=cams

And read the sticky about Marks' earlier use of the Ej22T block against the DOHC Ej25 heads. In short, don't bother changing the cams.

I don't think its' included anywhere online, but at one point Mark installed v3 STi cams into his DOHC Ej25 heads. Those are the only ones that will fit( ie Ej20K cams). He hated what they did to his powerband. He did pick up 25 peak horsepower, but the car fell flat on it's face down low. It took more than 1000rpm more to make the power. He literally only ran them for 48 hours before he tore the engine apart and took them back out. Now he uses them in an NA engine that revs to 7500rpm and runs stock DOHC Ej25 cams in his stock heads...
1974 Porsche 914 Cam Am Limted Edition AKA the Bumble Bee
1973 Porsche 914 2.0 l -Suby swap pending
1968 Porsche 911t survivor 47k original miles
2000 2.5RS daily driver.
1999 2.5RS w/ 50+ extra whp
Suby Hai!
All_talk
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Post by All_talk »

Thanks Matt, great info. :)

And the deal on the heads got even better, all I have to do is change out one front axle on his wifes OB and the heads are mine free, and he's buying the axle.... pretty sweet.

Gary
No matter how broke I am... I always seem to find two cents.
206er
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Post by 206er »

sweet deal!
1994 Touring Wagon: ruby mica, 5mt swapped
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