My Evo 5 got it's cambelt done yesterday.

The car itself has had a little work done to it, Turbo back exhaust, intake, intercooler, hks cams and adjustable gears, and possibly ECU tune.

It pulled hard as hell before I got the cambelt done, and when i got it back,
it's not even comparable to a bone stock Evo, it barely even pulls now.

When they did the change at mitsubishi he said he was careful to leave the timings as they are, but from what i gather something must be off. I guess what i'm worried about, is that because they can't tell what the cams are (264,???) am i correct that I may lose some power even if they try and fix the timing?

Crapping my pants a little because I loved it how it was before, and don't really want to sacrifice that timing. Am i justified in this worry? Or do i not really know what i'm talking about.

Any opinions/expert advice are welcome, or correction of anything I have said and likely have wrong

 

If power is down 99% the timing is off. Unless they also flashed a stock rom.

 

Hey Thanks for your reply. He took off the cover again and double checked everything. Two of them did it and said the timing is perfect. The guys at mitsi are really stumped. It just doesn't feel like it has the low end torque it used to, it really used to pick up and go like a one inch punch. They also mentioned that the boost looked a little low, ~12.5psi peak and they are looking into that next week. Is it possible id really notice that much difference if the boost was lower? Nothing they did could have interfered with it apparently. Is a boost leak also a viable option??

Thanks

 

Oh and also they haven't flashed the ECU, which is good because I beleive it has had a custom tune mapped onto it.

 

lower boost = lower power. sounds like you have a boost leak. could be other things, but that's what comes to mind first.

 

Okay cheers mate. Is it possible that happened after the beltchange? I.e they've bumped something and missed it despite checking over everything? What should it be boosting at given the minor modifications it has?

 

They shouldn't have needed to touch any IC piping nor couplings, but you never know.
Boost should be whatever it's set for based on Ecu, if tuned, boost controller settings, etc.

 

Yeah He said they didn't touch any of the stuff he could think of that would effect that. Yet somehow the boost is down to 12.5psi from ~15 (i think).

Surely 2.5 psi wouldn't be noticeable difference that I feel as much I do? Even my friends said it doesn't pull like it did before. Its driving me crazy haha

It's really bothering me because i'm worried they won't be able to get it back to the way it was before. And no Boost Controller, boost is set manually. Even if when they unplugged the ECU, if i had a custom tune it should still be there from what i gather as it was flashed to memory.

I really hope they can track it down and it is just a boost leak or something. So frustrating becuase I know it can go faster, the difference is night and day,
but he said it seems to pull good. :/

 

Only running 12psi? Not that familiar with an evo5 but that seems low.

I would do a through boost leak test first. Is it stock turbo? Check your boost controller and wastegate as well.

 

Yeah I figured these things are supposed to be running at least 15 psi stock? It was definitely running 2psi more before the Cambelt change. And yup shes on a stock turbo.

Okay ill get them to do a boost leak test. I have a feeling something like that's happened and its leaking boost. Fingers crossed thats it and not something harder to track down

 

Since this all started with a cam belt swap it would be a good idea to check that all the timing belt marks still line up. If the belt is out of time all this other investigation will be wasted.

 

Yeah man ive had him recheck and he got another mechanic who who also Said the timing is perfect. Quite niggly really

 

OP stated timing has been rechecked a few times and all is well.

 

What I didn't read is the OP having the mechanic take him into the shop and showing him that the timing marks are bang on.

I've driven a 4g63 since 1992 and have been on one board or another supporting the cars since 1993. In that time I've encountered numerous accounts were professional mechanics screwed up belt timing. In my own work I've been adjusting belt tension only to hear the thump of the belt jumping a tooth at the crank sprocket.

So, belt change and down on power, check the timing. If it is okay, cross that possibility off of the list. Assuming it is okay could lead to a frustrating experience.

 

I doubt OP's mechanic is lying to him nor ignorant to how to check timing. That would be bad for business.
Unless it's more of a "guy I know" than an actual mechanic....in which case you should see for yourself LOL