I listed the comp. ratio for the DOHC - that's the EJ25D.

 

GD

Now I see it. A guy on SL-I.net is using a cosmetic gasket and is getting a compression ratio of 12:1.

If you are asking weather the frankenmotor is an interferance engine - it almost certainly is, yes. The thicker head gasket is because the piston will hit the HEAD surface not because it will prevent it from hitting the valves if the timing belt should break.

 

Interferance vs. non-interferance is a silly discussion. If changed on time and attention is given to the water pump and idlers the chances of a timing belt breaking are almost non-existant. EJ timing belts are VERY strong. I have changed literally over 100 timing belts and to this day I have not seen a single one come in broken. I've seen seized water pumps, cogged idlers, and other nasty tricks but not one broken timing belt. At this point it's just not a reasonable argument against the interferance engines.

 

The compression ratio of the EJ25D/EJ22E Heads/EJ25D gasket is 10.5:1

 

The compression ratio of the EJ251(3)/EJ22E Heads/EJ251 gasket is 11.4:1

 

The compression ration of the EJ251(3)/EJ22E Heads/EJ25D gasket is 10.4:1

 

25D's are the most common EJ25's right now that are availible used - and the 10.5:1 ratio is slightly better than a 251 w/25D gaskets.... and there has been some reliability problems reported with the 11.3(4):1 combinations so we have stayed away from that one..... though I can imagine it really tears it up before it blows!

 

And to the guy that says a CAI is worth 17 HP - you are most definitely mistaken. In fact the stock intakle IS A CAI and is not a significant restriction. You get more noise with your cone filter setup and your brain tells you it's faster because you really want to beleive it is. It is very likely slower due to being a warm air intake from the engine bay instead of a CAI from the wheel well.

 

GD

 

 

like i said i was told it was better hp with a cai....and no i wasnt stupid as to put in a hai lol....i routed it into the front bumper through the fender to its truly a cold air intake.....and the resonator on my car just looped down to the bumper and back up to the airbox so no....wasnt a cold air intake by any means. thats why i changed it. it is faster now .....just a lil bit but i do notice a difference just like i have on (almost) every car ive done that to. mostly throttle response though. its snappier. maybe te guy that told my 17 hp increase was b.s.ing me....possible but he said it came straight from a subaru dealership mechanic because the stock airbox was pretty restrictive. (so he says)

 

when i lost bottom end it was because of my oversized (free) muffler from magnaflow 3" inlet 4.5" outlet. sounds good but lost alot of bottom end torque. at least it doesnt sound like a fart can exhaust (like a honda)

 

-jarrid

They are Cometic gaskets, not cosmetic:)

Now I see it. A guy on SL-I.net is using a cosmetic gasket and is getting a compression ratio of 12:1.

 

And I doubt his engine is long for this world.

 

GD

Who knows. So just curious. I want to be in the 11 compression ratio. 10:5 seems to be what stock 2.5s are. Hoping this frakenmotor build will put me in the 15's at least at the drags.

If you want to go that fast - you need a turbo or you need to lose a LOT of weight.

 

GD

I run 17.1's STOCK in my 2.2 with the automatic. I also live 150-300 feet above sea level here.

 

If the 2.5 hybrid won't shave on a second in the 1/4 that is pretty sad. I got friends here with cammed 2.5's full exhaust and running 15.4-15.8.

 

It seems you're in portland too. From my understanding a stock 2.5 5 speed can run low 16's. I am not sure how 200chp 2.5/2.2 build wont get into the 15's.

Edited September 11, 201114 yr by 96LegacyEJ22