Looking to get some technical advice and a more in depth knowledge of this. Lets throw around ideas and such on this topic.

Recently I had a timing belt job done as well as a balance shaft belt done with all new oem tensioners, pulleys, gates water pump, and gates belts. this was my first rodeo with a t belt service on my evo. I opted to let someone else do the work to avoid kicking myself if something went wrong if i did the job. what follows is the full story of my experience and both the mechanic who did the job as well as myself were confused on the results when done.

I dropped my car off on a Saturday morning to have the job done. we agreed to change both belts, replace all the tensioners and pulleys as well as the water pump. the mechanic recommended doing cam seals while we were at it to prevent an oil leak down the road which could lead to having to do a timing belt. at first i was skeptical since I was pretty sure the previous owner of the car had done cam seals when he installed the hks 272's. I finally decided maintenance and anything preventative was a good idea and gave him the go ahead to change cam seals as well. I was under the impression that he would be removing the valve cover and cams to do this which is important later on in the story.

He promised to have the car done in a day since my work schedule is crazy and i was on call. He even agreed to do this on a saturday. so at about 1pm i get a call thinking it was him saying he was done, but instead he asks if i knew the mechanical timing was off previously. Of course my answer is "well hell no, the car has ran fine since owning it and has made 356/357 previously with no issues. at this point he tells me both intake and exhaust are off by a tooth or around 4 degrees with the intake being retarded and exhaust being advanced. he asks if i want to set the mechanical timing back how it currently is or put the car back into correct mechanical timing. of course i tell him to set it back to correct mechanical timing like anyone would.

a few hours go by and i get another call saying the car is done ready to be picked up and he lets me hear it over the phone... the cams were stomping the ground harder than ever before and he says it was due to it being put back into correct timing. when i arrive the car is idling fine with a hell of a lope and nothing else seemed unordinary. he had taken pics of the cars timing before and after on all of the timing marks and showed me to prove the car was in fact not in time when i brought it to him and that the timing was corrected. he then asks if my lifters have always been as loud as they were. I told him nothin unordinaraly loud and told him i thought the sound he was hearing at idle was either my throw out bearing since it has always made a rattle since owning the car or the skid plate rattling on the ic pipe or dp. he shrugged and was like ok if you say so. i pay him and get in the car to leave and pull out of his drive, and this is where things got weird and took a turn for the worse.

Immediately when i sat in the car i noticed vacuum was at only around 5-7 in hg. the car use to idle at around 15. i figured this was due to the timing correction. as soon as i pulled out the car felt like a dog down low with no power, add to that that on acceleration the lifters now sounded like they were going to come out of the valve cover. they were actually audible over the exhaust and drowned it out, and i have a 3" tbe with test pipe. at this point im thinking huge mistake to take it to this guy i need to pull over and call him and see whats up. i pull up to the first stop sign and the car idle surges from 1k to 3k rpm. i shut the car off tell him whats going on and he comes up the road to take a look. at this point im thinking im getting screwed so temper is up. My first thought is he popped the cams and did not bleed the lifters when changing cam seals. when i asked him this he says he didnt pull the cams. I jumped to conclusion that the seals werent replaced and he explains he did so with a seal puller and some type of pick so the cams never came out nor did the valve cover come off. He offered little explanation as to why the valve train is now so noisy and begins to say that i should try driving the car home and the lifters will probably quieten down and that maybe holding the cams in position to do the belt job bled them down. at this point im thinking he is trying to **** me over seriously so i tell him thats not an option and im uncomfortable doing so that i brought him the car with no issues and now all the sudden it has issues minus the timing being corrected. at this point he makes a comment saying maybe i brought him the car that way and trying to avoid confrontation i tell him i would appreciate it if he kept the car over night and went back through his work the next morning when it got light to verify things were in order since he guaranteed his work before i allowed him to do the work and that it was his reputation and not mine on the line (basically saying in a nice way if your pulling some crap this is your last chance to fix it or im putting you on blast). he agreed and i drove the car back down the block to his house and left for the night feeling very uneasy.

I went ahead and posted a few threads seeking advice on some forums and did not disclose any info on the guy just the issue and all i got was ya he is screwing you and sounds like the timing isnt correct and the sound isnt lifters but valves hitting the pistons. worried i went ahead and gathered info in case it turned into a civil matter, and started to jump the gun and disclose information about him. this pissed him off and of course led to us being at each others necks the rest of the night and the next morning. the next morning he calls and we go back and forth on why the car is like it is and tells me it will be ready in a few hours. few hours go by and i get the call to come back. i get back over there and he claims the lifters have quitened down substantially. the car is idling smooth and with no noise. im thinking ok what did you catch that was wrong. THIS IS WHAT IM LOOKING FOR MORE INFO ON: He explains to me that he used the adjustable cam gears i have and set the timing back close to but not exactly like it was when i brought it in. with the intake at +4 and the exhaust at -4 and there was virtually no lifter noise. He then says I did a compression check before and after doing this. with the cams zeroed out and in time compression was around 200psi across the board, and with how it is now and when you brought it in it was at 175psi across the board. I did not believe him at first since from what i have seen evos compression should be around 185 or so from the factory. he then says well every comp gauge is different and should be used just for a reference and be within a certain percent. he then says my theory is that the increase in compression caused an increase in combustion pressure which could could possibly be putting more pressure through the valve into the spring through the rocker and ending up in the lifter causing them to be much louder. that was his only explanation and that he talked to a few other mechanics the night before throwing ideas around. again i didnt believe him and asked for him to show me in person that timing was now correct and show me time stamps on the pics he took. The car was in fact in perfect timing, and he now had adjusted the cams back out to +4-4. i got in the car and vacuum was back up but not back to 16. it is now around 10-12, but of course not completely back since he did not want to risk setting it back how it was for fear of damaging the valves with clearance. i agree on that part, and cant believe i drove around for 5 years with the crank being 2 teeth off. when i pulled out the car now had its low end power back and the lifters were quiet. he suggested changing them and then zeroing out the cams and re tuning the vehicle.

SO lets hear your thoughts and opinions on this, how and why can changing the cam timing effect valvetrain noise. this is not a question of does it change the noise because i have seen it firsthand on my car, and my mechanic actually thinks the previous owner timed it this way purposely to make the lifters quieter to sell the car. Is his theory right because even he stated he has never seen it before and if asked previously to working on my car he would have said no cam timing can not effect the valvetrain noise in a 4g63. he has 20+ yrs working on 4g63 motors by the way.