Hey guys,

Attached is my dyno sheet from my last tune. To make a long long story short, I'm being told that the turbo is max out and won't make any more power up top so its not really worth it to rev past 6400.

My question is if this is possible for the turbo to be max out at 15 PSI or why cant I keep making more power up top with the cams????

I know the PowerLab kit isn't producing the numbers everyone thought it would but the limits were high aits for most among other reasons but I don't believe I had read about the turbo being max out.

Quick Overview on Setup:
Cosworth Pistons 0.20 Over Bore
BC Rods
L19s ARP Head Studs
ARP Mains
HKS Head Gasket
ACL Moly Coated Race Bearings

BC Stage 3 Cams
BC Valve Springs n Retainers
3 Angle Valve Job

UTEC
Snow Performance Injection 100% meth

Megan Headers
Plenum Spacer
UR Crank Pulley

3" Custom Exhaust w Vibrant Resonator and JIC Muffler



I am aware that these numbers are on a Mustang Dyno but the last time I tuned on a stock block on this same dyno and compared it to a DJ, I made less power on the DJ. So unless I jump on a DJ again I do not believe DJ numbers would be higher. My butt dyno tells me its 505. It doesn't feel that much stronger

Any positive or negative critiques welcome.

 

Nice build.

You did indicate that critiques were welcome, though. So, here are my thoughts...

Your power band is very narrow.

You selected 272 duration cams and are only running to 6200 rpm or so. Maybe the dyno rpm reading is off and you are running to 6500 rpm. I would use shorter duration cams for that max rpm, which should help a little with spoolup. If you want to get more out the 272 cams, push the motor to 7500 rpm. A billit girdle would be nice to add strength for the higher rpm use, but I'm not sure if you can do so without dropping the motor. Maybe someone else can chime in on that.

Also, check out the Sound Performance Racing quick spool valve to get the turbo to spool up quicker.

If you go with a quick spool valve and push the rev limiter higher, I think you will have a much nicer power band.

 

why did you stop at 15 psi? at 20psi where you just not making anymore power? Safe tune meaning what? You could be lo0sing a ton of HP if the timing is weaksauce. How much meth are you injecting? Should be around 6-800cc /min if you really wanna be able to push the timing.

Step up to a 1.01 turbine housing and you'll make more power.

 

bigger a.r housing like above post.

 

Yes all responses n critiques welcome. At this point I'm trying to figure out what may be causing this and what solutions/options I have to make more power. If I chose the wrong Cams for my setup then I'll have to live w that mistake for now :-) but if there are options On how to make better use of them I'd really like to hear them. I'll have to look into the 1.03 housing. The meth kit is the stage 2 and I'm using the biggest nozzle of the two that it came with. Don't remember the size but it's for 500+ hp according SP.
The tuner said the turbo is maxed out so NO^^ reason to keep raising the boost. I do not know what was happening when he raised the boost. I was not present for the tune.

I sincerely do thank you all for your replies. I plan on making some changes but just need to get a clear idea of the changes I can make and it's cost to benefit ratios.

I plan on a FRS, 1000cc injectors, and a better Engine management but if it won't be really needed or useful with this kit then I plan on selling the PL and getting a twin turbo which is what I should have done from the beginning lol

 

Go somewhere else for tuning. Your power peaks, and then you......stop reving..... Rev the motor out more and let the power carry like a table top. When it starts to decrease then stop reving there.

Also, a bigger hotside will help the turbo be more efficient for such a big engine. A single 35r is small for high HP numbers on a 3.5 liter.

 

The only thing maxxed out is your tuner.

35r can run 600whp on race gas.

If you were maxxed becuase of fuel system or octane, thats a different story..

Please let us know becuase that turbo is NOT maxxed out. Something else in your system is

 

I agree with the above posts. A couple questions...

• Who is your tuner?
• What size injectors are you running?
• What are your power goals with pump gas + meth?

 

BTW... I'd ditch that UR crank pulley and swap it out for a Fluidampr or ATI pulley. The UR pulley is not harmonically balanced and could lead to premature motor failure. You would even be better off with the stock pulley.

 

agreed! UR sucks!! stock pulley > UR... it ****ed up my front main oil seal

 

When I'm on it, it doesn't feel like it falls flat on its face at 6400 or so. It keeps pulling and pulling strong. Thats why I was a bit shocked when the tuner told me that is not worth pushing it beyond 6400
I am deeply considering a different tuner and this is one of the reasons why I started this thread. I just do not give up on some one wo due process.

Those are the answers I'm looking for. I do not believe the turbo is maxed out. If there is something else limiting me from producing more power, then I'd liked to know. I get the feeling I'm not being told everything and telling me that my turbo is maxed out was an easy way out.

I really do not want to get into discussions with "who the tuner is" for he has been very helpful throughout and is very knowledgeable. I will say it is a reputable shop that deals with Zs n Gs day in day out.
The injectors are 650s and I am pretty sure those are very close to being maxed out but I'd think running 100% meth injection would push it to about 550. I'm not looking to make ridiculous power with this kit on pump and meth but 505 and the power band dropping at 6400 just seems like I'm being cheated somewhere or something else is causing this. Just trying to find peace of mind if what I'm being told is factual or not.


^^Wow
Well, its an easy swap, so I may just do this. I'd hate to have parts wear out where not suppose to.

Thanks

 

I have the powerlab kit with the 1.06 housing and 264 cams. The larger house reduced the spool up time over the .82 housing and the 264 cams maded power all the way to 8100 rpms. My problem was insanely high back pressure and sky rocketing AITs. The car would not make anymore power after 15 psi as well. This powerband is way different than mine at 15-16 psi.

 

that looks pretty laggy too.. 400ft/lbs at 4900rpm?.. for a 35r with the small housing..

james.. what does ur graph look like? pic?

 

+1^^^^^

 

bulls eye gt35r's bolt on dsm turbos can make much more power than that on smaller motors. 15psi, sounds like your tuner as others have said. It could be something to do with not being able to hold higher boost levels, so the tuner thinks the turbo is maxed... But imo a good tuner is going to seek out what is limiting the kit, because your heads are pretty well worked... and a gt35r is capable of making really good power. Also the spool up seems slow...
I'd actually check for leaks... Would explain the lack of more power on higher PSI, or not being able to reach high PSI levels, and would explain the slow spool up.

 

Very interesting topic i hope you get the answers your looking for drock because this has me baffled too.... i think a leak test is a good idea.... lets see what other help you can get from this!

Also i wonder if the modified piping from when it was on rubens car has any effects on it or maybe not but even though they are minor who knows if it obstructs the air flow??

 

Modified piping??? That is something that probably should have been mentioned in the OP of this thread. Please elaborate on what has been modified on this kit.

 

I will look for it and post it asap. My car is at full boost, 15 psi, at ~3500-3600 rpms, climbs smoothly to 465whp (DD dyno) at 7200rpms and starts to taper off but does gain another ~10-15 whp between 7200-8100rpms. It starts to boost at ~2800rpms in 4th gear and rapidly hits full within 800rpms then has a smooth powerband to redline. This dyno looks very abrupt and ends quickly. The funny thing about my dyno is there are no signs of the turbo running out of steam but it will not make power after 15-16 psi. At this point, the AITs start to climb fast and the back pressure is at ~2.5 to 1 ratio before the exhaust housing but it able to make power to redline.
P.S. My car has the rev up engine, JW S7r cams, no head work, gt35r with 1.06 housing, Strup headers, three inch powerlab midpipe into an HKS dual 2.5 inch exhaust. I did remove the HKS portion of the exhaust and only gained ~5 whp on the dyno. Also the weld at the wastegate blew open during the dyno section; It looked like a bad weld was the cause of it. After much discussion, Powerlab was willing to replace it for free but I didn't want to deal with the down time so I had a welding shop tig weld it with gussets. Hopefully the high back pressure doesn't blow it back open but I guess time will tell.

 

man please.. if you dont know what your talking about... dont lead the OP in the wrong direction...

first of all you CAN NEVER.. compare it with a 35R on a dsm 2.0L... obviously the 35r on a dsm or sti with a small motor make more power and run higher boost pressure ... yes a 35r can make great power on pump gas in a dsm... but it is not the same for the 3.5 V6. a single 35r in our motor is actually a pretty small turbo for pump gas..

OP needs to explain what is done to the modified piping, first. .. and then he should do a pressure test... If his power band is fixed.. he will spool up faster and make a bit more power.. all OP should be worried about is getting that power band to match up better.. as far as power.. i think there great numbers for pump gas and small housing

op, if you want to wake up that turbo .. run it through some c116

 

very discouraging news for single kits.

wonder what the deal is....