Dynoed my SP61GT very dissappointing #'s

[twinturbozs]

I got my Supra dynoed today, and confirmed my seat of the pants feeling. I ended dynoing 316rwhp on 18psi. Seems as though a few others who have dynoed their SP61GT have gotten 380-400rwhp. This was using a dyna-pack, whether or not it makes a difference.


A few problems i encountered. I maxed out my profec B boost controller and can only get 18psi on hi setting but held steady without any fluctuations. When he let off at the end of the run, a puff of white smoke would come out of the exhaust. The turbo has approximately 5000 miles from SP. I am running a stock IC.

I was also under the impression that with my setup, i would be running extremely rich. We ended up having to increase fuel pressure to 42psi to keep a safe AFR. The SAFC adjustments didnt have much affect at all.

ngine Specifications:
Rebuilt 7M-GTE
Greddy 2.0 mm Metal Head Gasket
K&N FIPK
NGK Spark Plug Wires
SP61GT
Apex-i S-AFC
Lexus AFM
550cc Injectors
Aeromotive AFPR
Greddy SP exhaust
BIC DP
Testpipe
MKIV Fuel Pump

Dyno sheet

Boost Curve

Air/Fuel Ratio

 

[bigaaron]

The hp and torque graph is all over the place, just like the afr. If the safc wasn't making any change in the afr, then that is probably the problem right there. I bet the safc isn't wired in correctly or has incorrect settings for your engine.

Do you have an upgraded fuel pump? Was the fuel pressure steady during the dyno pull? You should not need 42psi of fuel pressure at 300whp on 550cc injectors. If everything was right you would probably have to go down to about 35psi to keep it from running rich without taking out huge percentages of fuel on the safc.

Whatever the problem, I would not blame the turbo at this point. That turbo should be able to make 316whp at around 10psi.

 

[7MGTEsup]

Yeh sounds like you have some serious issues putting up the fuel pressure on 550's, maybe you have some bad injectors or your fuel pump is about to die.

 

[MRSUPRA]

Yeah, your about 100rwhp low for that boost level on that turbo. Definantly got problems. My only advise is to go over everything starting with the most obvious like spark plugs and vacuum leaks.

 

[bigaaron]

The boost graph looks fine, I don't think a boost leak was causing the problem.

 

[MKIIINA]

weird looking graph there man. i had a similiar experience when i dyno'd my sp61gt also when i was on similiar mods as yours (see bottom of sig). My problem ended up being faulty KS/KS Wiring. Im inclined to point the finger at SAFC for improper setup and lack of a good fuel pump for your issues as your af isnt as smooth as id like to see under boost especially around 5200 rpms where you get a blip, also when boost starts to build you see some hiccups on the way down when boost builds.

as for the smoke check the turbo for shaft play and report back

 

[twinturbozs]

I forgot to add that im already running a MKIV fuel pump. I do know the SAFC is working because i can adjust it at idle and i hear the idle richen up or lean out if i make adjustments at 1000rpm.

My other concern, how is it, that i can only get 18psi on max settings. I have a 14lb wastegate, which means i should be able to boost closer to 28psi if i desired. My smooth boost curve leads me to believe there isnt a boost leak any where.

Would the knock sensor throw a jagged graph like that?

 

[bigaaron]

On the smoke thing you would want to pull and inspect the plugs to check for oil burning in the cylinders.

 

[dbsupra90]

My other concern, how is it, that i can only get 18psi on max settings. I have a 14lb wastegate, which means i should be able to boost closer to 28psi if i desired. My smooth boost curve leads me to believe there isnt a boost leak any where.

Would the knock sensor throw a jagged graph like that?

are you running an internal or external gate?

yes and no about the knock sensors. it is a very touchy circuit, and if there was a problem you would have a code (52). but, if it was sensing knock it will retard the timing til knock was gone. then if it knocked again, it would retard again. that could cause the jagged edges. what octane were you running on 18psi?

 

[twinturbozs]

I was running a mix of 100 and 91 which probably averaged around 94-95. The turbo is running an internal wastegate.