Shouldn't the owner of the car check the car out prior to going? I know prior to taking my car to get tuned I do an inspection but I guess everyone is different.

 

not for 34 psi on e85!!

 

I dont think a shop is obligated to go over stuff like that when someone brings a car for a tune under any flat rate. If the cust pays you to troubleshoot the problem thats a different story.

 

EVO8LTW: I thought that all the other possibilities that you posited were insightful, except for #3. I can't quite visualize a 3" I.D. hollow, straight through pipe becoming obstructed with corrosion. Unless they were like huge cotton *****.

 

Good point I guess.

 

'
The shops I have gone to they have went over everything for me while I was on the dyno when I had some issues and we found ..

2 boost leaks.
plugs were bad and not gapped properly..

I guess every shop works different All I know is that my old tuner use to work until the tune was top notch and even if I took till 5:00 am..

 

True but he could of done the guy a boost leak test check the plugs and do a compression test all in all takes like 45 min tops for everything..But your right he should have gone over the car himself.

 

I'll try to answer this as best as possible.

(1) Could the cams be off a tooth? Was the car particularly knock sensitive?
Possibility? He said the car didn't knock at all on the last 4th gear pull.

(2) Could your Magnaflow muffler be coming apart and have an obstruction?
Possibility?

(3) Could the test pipe be obstructed with corrosion?
Possibility?

(4) Is the air filter particularly dirty (I lost 70 whp on a car once due to a dirty K&N filter)?
Don't think so.

(5) How's the compression on the motor?
Doing a test soon.

(6) Boost leak check?
For some reason I can't put more than 2psi in it when I test...

(7) Is the throttle plate opening 100%?
Not sure.

(8) Could the brakes be dragging?
Don't think so.

 

He changed the plugs on the dyno.
I also changed from a turbo xs mbc to a grimmspeed ebcs prior to the tune and when I got there he made me change back to a mbc, so I had to buy a new one because I didn't have my old one with me...that would've been good to know.

 

what are you using to check your boost leak test??Do you have evo scan and a tractrix cable??

 

What am I using for a boost leak test? Just a home-made boost leak tester.

I currently do not have evo scan/cable, but my buddy who tunes a bit is getting one soon.

 

OP: I have an FPRed and Cozzy M2s, and 26lbs of boost made 460whp on 93pump. so as far as comparisons sake the car should make a lot more than what you posted and there has to be some type of bottleneck somewhere. a boost graph would be a great help in figuring out any issues, you should have requested that asap after your tuning session esp knowing that there is a restriction somewhere. my boost spikes to 26 and tapers to 23 by redline. im also on a single walby and 880cc precisions. i want to make a jump to popcorn fuel but will need bigger injectors and try and see if i can pull it off with a single pump.

 

what are u using a bkie pump or a compressor??Your car should have been dynoed in 3 rd gear that's the closet to 1.1 ratio it makes your whp and tq go higher in 4 th gear so your and tq are probably like 15 lower.

 

I'll request a boost graph.

I actually tried both.

He did both 3rd and 4th gear pulls.

 

what made more power and tq?I looking at your mods there not much but there solid Im thinking of some other things it good be did you check the plugs and when is the last time you changed them???what was your arf's??