I don't know about the OP, but I'm also holding about 23-24 psi @7000 on a stock 8 turbo with 10.5 hotside. I'm using ECU controlled boost with a modified stock boost solenoid. Could be that the Truboost is holding you back but I'm just guessing cuz I'm not real familiar with them and how they work.

 

Adding more preload to your WGA will help lessen or eliminate taper.

 

Ah i see, well i will try adding some more pre-load to the wastegate over the weekend

Thanks

 

i've tigtened my actuator today widge and it does help. just don't go to far. you'll know when you have because you will get creep.
remember to drop duty cycles a little it makes a big difference low down

 

is the weight correct? seams heavy ? mine with 6speed is only 3348 with me in it
weighed at a weigh bridge. stock tyres? mine are 18's and very close to your tire numbers

 

here is my 05 MR runs (one with 23.6 and the higher with 23.8 peak boost) just today for the comparision.

These runs are on straight 91 oct here in southern cal, about 80 degree nice weather. Car has the following performance mods:

- full turboback with testpipe.
- AEM intake.
- Hallman manual boostcontrol.
- BuddyClub 272s.
- Precision 780cc.
- APS BOV.
- Exedy twin metallic.
- stock advan tires.
- Self tuned ecuflash targeting A/R 11.5 down to 11 after 7k rpm with minimal knock sum.

I used the default for MR weight which is 3285 lbs + my weight 155 + subwoofer and tool boxes 30 + laptop 5 = 190 lbs, which resulted in 3475 lbs. Adding or subtracting 10 lbs will make about 1-2 hp different.

Basically simple bolt-on stuffs, nothing to brag about. Just the same virtual dyno result for those who interest.

I'll try to get it tuned more boost with 100oct, dyno it and then put on my newly HKS turbo kit with 274/278 cams to see how it would go.

 

looks real G. maybe thought you'd get a little more with the cams!? maybe the gas sucks?

 

well 0 knock so that means there may more power that left on table to be extracted. I ran out of times since it's Halloween night here and the cops are out hunting.

 

Well most people use the "stock" curb weight, which for GSR is 3262 and for MR 3280.

But no modded car weighs the "stock" curb weight. A TBE takes off 20-40lbs, going to a BR intake takes off like 4lbs, etc, etc. Also level of gas. I have weighed my car and know that at 1/2 tank, no driver, it weighs 3000lbs. Its good to know your exact car weight when using these virtual dyno programs.

His tire height is correct if he is using 235/45/17 (stock tire size).

 

Cool. Yep, if you get creep, you have added too much preload. And it will raise your "base wastegate" pressure, and you will need less duty cycle to get the same peak boost.

Now just raise the duty cycle above 5K and totally eliminate that taper.

 

I have a hard time believing the numbers here too as I made about 400/400 on e85, 31.5 psi, stock 10.5 hotside 8 turbo, HKS 272's, and full boltons.

 

Im using a truboost so i am unable to do RPM boost control

either way im at 95% IDC up top as it is with the taper to 17psi so i think if i fix this tapper issue im going to run out of fuel,

So maybe some injectors then ill adjust, how many turns generaly?

So if i tighten too much it will creep boost, so i should do it 1 full turn at a time and test?

 

Like I said in the other thread, you need more smoothing.

 

Yeah, do one full turn, then test. Make sure to test in 3rd and 4th. If you get creep, you have added to much preload.

 

Very impressive!