is the IM the street or race version?

 

lol not sure...its the sheet metal with the velocity stacks

 

it sure looks like a miss or possibly a boost control issue. what are you using to control boost?

 

What fmic you using?

 

hallman mbc and 4" ETS intercooler

 

Which sheet metal?

do you have a picture?

Definitely something is not right....

your graph should have looked like the one below.... The pulls were made all the way to 8900rpm....




Me, without having such aggressive cams, without having an intake manifold or a throttle body, and without using so high boost or meth i got 547awhp on a dynojet duting the winter running 10 or worse afrs at around 28psi....

Why i am mentioning my car? Its a similar setup with a similar turbo....

I doubt that its the exhaust. i had the TurboXS back in the day and simply is one of the straightest and more free flow and loudest catbacks in the market...

Do you have a cat or a test pipe?

 

Lets put more detail into the situation since I'm the 'tuner' involved.

Boost held steady.
No more than 2 counts of knock through the pulls.
Afrs between 11.0-11.8 made no difference.
Car down on power 30-50hp at every boost level vs what I've seen personally.
3-5 degrees of timing changes made no difference.
We removed the intake filter to see if that was clogged--no difference.


-Car feels "choked"-- three resonators on the exhaust is a great place to start.
-Old school magnus isn't my favorite, but not the cause of the power drop-off.
-Sparktech seemed to be working just fine, but I wouldn't mind trying stock ignition back-to-back just for argument's sake.


More details to help paint the picture,,,

Motor was built by unknown shop. Still under 2k. Cams are unknown. Still no compression test results. No leak-down test done yet. Down a little on oil before the tune.
Boost leak test went good,,, plugs were good.

Power needs to be supported. There is a bottleneck here. When it's opened up the dyno will reflect it.

What do you guys think??

Ninja edit::

The 'cork' started taking effect around 62-6500 as you can see that's where the power fails to rise. I use 0 smoothing to isolate issues-- very squirmy after this rpm as well. My money is on the exhaust.

 

Motor was machined, balanced, and assembled by Headway Performance. Howards rods, JE 2618 pistons 8.5:1 with upgraded wrispins, arp main studs, l19 headstuds and stainless o ring.

 

- The exhaust would be the easiest/cheapest thing to check first...

- Cams i thought he said GSC S3s...

- And i agree with the particulat manifold.... Isn't it the version when BR made the manifold test and the car lost power, worse than stock?

Is it a Speed Density setup or a MAF?

Since i ve seen other cars of yours, i am sure that you can figure it out with the OP and get the 600+++ that he should be seeing on the 6262 and that boost level with meth!

 

Thanks for the support kouz...

Vid on the last pull....




Car was slowly increasing in power-- but it wasn't up to my specs. I believe in a firm foundation before building a skyscraper-- we both decided to take her down and work out the bugs. I'm more than happy to see this project to completion.

 

see if the timing is right maybe whoever installed the first set of cams had it off a notch just throwing that out there as well

 

3 resonators in exhaust!!!!!!!!unbolt the exhaust after the test pipe and do another pull, could be a quick answer to see if another one is needed

 

+1, it is a quick and easy way to find out if it is the cat-back.

 

Im gunna say it again the manifolds gotta go. then check the cams and timing and put the car back on the dyno with no exhaust and see what it does.

 

So Headway installed the cams and installed the motor into the car?