Recently upgraded my GT35R with a 67 mm TO4R compressor wheel, everything else stayed the same 0.82 A/R turbine housing and dynoed it at 35 psi with C16, on a new 4wd Dynojet here, we made 608 WHP.

Previously on a standard 35R compressor wheel, it made the same?? The 67 mm wheel is suppose to flow 75 ib/min compared to 65ib/min of the 35R. Whats happening?

Worst was when we injected 50 hp of nos, it made only 617 WHP at the same boost?? This is boggling me....

A/F with turbo only is about 11.8, we tried leaning it to 12.1, nothing happened.. we tried running 37 psi, nothing happened!!

We then proceeded in changing over the turbine housing to the 1/06 A/R housing, spool up was so much slower and yet it made the exact 608 WHP??? Is the turbine wheel just maxed out??

The fact that the nos was on and running a 11.6 A/F with nos, makes so little more is beginning to puzzle me...

Am trying to upload the dynograph here...

I know guys here have made more with the 35R, but the fact that my best run on my last pass with the non upgraded 35R was a 10.41@ 143 mph with a 1.9 sec 60 ft!!

Any help will be appreciated!!

 

Wheels slipping on dyno....?

 

Monitoring timing & knock?

 

In my opinion, you shouldn't have changed the afr , but timing. You will make more hp changing timing than afr. I think the 35r is maxed out on efficiency. Once you can't make any more hp and you're still cranking the boost, you know it's time for a bigger turbo. gt47 woot!

 

There was zero knock levels at that boost, graph was smooth and there was no rollover of power, basically it was over 600 from 5800 rpm to 8000 rpm dead straight!! timing at that boost was at 20 deg advanced.. I thought dynojets don't slip??

 

If you had a 1.6 60ft it would be close to a 10.00(or maybe even lower) your trap is speed is great just work on you 60ft time.On the dyno I have no idea.

 

only 610??!!?!?!!!?!??

 

Isn't the nos suppose to work over whatever the turbo flows? 10 hp more on a 50 hp shot of nos is just weird...

 

What are you runing for engine manegment?

 

Its running an Autronic SMC engine management, fuelling on 1000cc Sard injectors with twin Bosch 044 pumps.. Everything else is running fine, just no more power even with the nos switched on..

 

i'm thinking this with a stroker kit?

is your dynojet corrected after the runs?

what sorta intake manifold? fuel injector cycle maxed out? ems? fuel pump?

spark plugs changed after every run?

did you try to run the dyno at 11.3 afr?

try race gas?

try gt40?

 

that sucks. well, if you want more power, just drop the 4g63 and stick a twin turbo LS-1 in there. that would help.

you should be running better than 10 sec with that setup. 1.9 is pretty bad...

 

Nope, this this is still a 2 litre bottom end running 9300 rpms, running a VENOM intake manifold on C16 fuel as mentioned...

 

What were the temps like, was it more humid the most recent time your EVO was on the dyno. I mean temps and etc. can play a pretty big role in dyno numbers, the problem may not lie with your car, but with your dyno or dyno conditions. Well if you were able to run a 10.4@143MPH on the previous setup, then if you are truly making more power, then you should trap higher. Take the car back to the track and see what she runs.

 

Street radials, lots of wheelspin unfortunately...am going full slicks soon...