legacycentral bbs

need help is it true that ej18 cams are better then ej22t cams becuse they open more and longer

anyone please

I would think it depends on if its naturally aspirated or forced induction.

Yeah, you don't want the big overlap performance-minded N/A cams would have on a turbo motor. The overlap helps a N/A engine suck more air into the cyminder at higher rpm, but on a turbo engine, it just wastes power out the exhaust.

Steve

..but on an N/A, the EJ18 heads and cams would do something useful? Should I be looking for a set? That would up the CR, right?

ok so dont put them on the turbo motor. got it evolutionmovement.

I don't know if they have large overlap, It's just an educated guess. I could be wrong, but if they are cams optimized for N/A performance, especially in a small engine where you'd want more top end to make up for the inevitable less bottom end they would almost definitely have fair overlap.

Steve

The EJ18 heads are substantially different than the EJ22 heads and would be a downgrade for either a turbo or NA build. The valves are smaller, and the combustion chamber is significantly smaller. Even on an EJ22T block, you would still be in the realm of 9.5:1 CR. And then there is the issue of a couple of extra breathers on the backside of the heads for EGR and some other stuff. Don't waste your time playing with these heads at all.

But you might look into the cam thing a little more. The cams will likely fit into a set of EJ22 heads. We are tearing down an EJ18 this weekend, and maybe I will get a chance to pull the cams out and compare...

evolutionmovement you think they would give me more top end i have the durations on both of them and i will show you and then you tell me what you think

Matt Monson thanks let me no what you find out it could help use all out.

It's quite possible. The 2.5RS heads apparently help quite a bit on the EJ22T. The car that i rode in the other day had some 2.5RS heads on his turbo motor and it pulled pretty hard. I think a 12.9 at this altitude is pretty good for an automatic awd car.

Large overlap will only help an N/A car's top end. Turbo cars will just loose boost as the exhaust valve is open at the same time as the intake. Low end N/A power suffers, too. The idea behind the overlap is that at higher rpm the open exhaust valve with it's escaping exhaust pulse creates a low pressure zone behind the pulse which helps pull more air through the open intake valve and into the combustion chamber.

Steve

Ok,
So, the EJ18's intake ports are a full 1/4" smaller than the EJ22T's, even though the valve size is the same. Also, the EJ18 has roller rockers, and because of that the width of the cam lobes is substantially different than the EJ22T's. You could take the whole rocker assembly and cams from an EJ18 and put them into an EJ22T head, but putting the whole head into your car would be a waste of time...

i actually tried 1.8 cams and rockers on my 2.2n/a, no power and it sounded like a v-tec at high rpm. imo useless, maybe just the cams would work but i lost patience and put the originals back.

is any 2.5 head the desired upgrade for the ej22t's, or is there consensus on what is the best / most cost efficient head upgrade would be? I'm thinking head/headers/turbo change all in one upgrade... probably port/polish/3-angle valve job standard dealie for the head, coating for the header, coating for the turbo (obviously this is not going to be a quick upgrade). Suggestions?

So far, jet hot or hi per coat for the coating, and a td05-16g for the turbo. perhaps even a ported monster 16g.

Free5tyle
Read the sticky at the top for Xephyr's set up...