I finally broke down and went to Dynojet Dyno in Balanced Performance.

The setup again:
Stock engine 112000 miles
Exhintake cam
460 cc injectors
Garrett GT28R (2560) turbo (welded wastegate)
Tial 38 mm external wastegate with separate exhaust
3" exhaust
Tullos EBC
Emanage Ultimate piggyback
Ebay Blow off valve
RX-7 Gen II modified intercooler.

7 psi 184.1 hp 160.3 lbf/ft
8 psi 191.8 hp 166.9 lbf/ft
9 psi 208.9 hp 179.8 lbf/ft

the torque curves are very flat, boost start at 2000, is 5 psi at 2500.

Never tried more than 9 psi since the road race class, KCC and Nasa Super touring are based on power/weight ratio, and the next step above 210 hp would have been 244 and I assume it might be too much for this turbo to try to be there 40 minutes at the time. 9 psi should be quite conservative boost.

Comments?

hrk

 

nice! post the plots when you get a chance....makes me want the bigger displacement, and it takes me about 11-12psi currently to acheive the same results.

 

That's awesome! 3" exhaust FTW.

I went to the same dyno at BPM a few months ago. The have a real cool facility.

 

Have you run it on the track yet? what's it like?

 

210whp from 9psi is very good. Wonder if the exintake cam helps keep the torque flatter on the topend.

 

That's it, I'm going to order a GT28R or disco potato soon! nice numbers!

 

Yes I have, with stock injectors and poor setup.
Here is description:
http://russmarshall.com/v/cars/cmc7/cmpfeb2007/

And will again next weekend in Road Atlanta. Come and say Hi!

hrk

 

The 17th & 18th?

I'm right up the road from RA, though I don't think there's a chance of having the miata ready.

 

Won't be there. Got a baby due in 4 weeks and LOTS to do on the house. I hope to get A race in this year.

Just wondered if you'd had it on track in a "sorted" state.

 

Numbers look great.

 

looks good. i'd expect you'd run out of injector past 10psi or so anyway.

 

Thanks,

I scanned a combination sheets with 3 documented runs.



Take a look at the torque, there is not buttloads of it, but it is pretty flat through rev range.

Please, remind me how to make O2 clamp with EMU?

hrk

 

Cannot say for sure, but I doubt it since I even highest cell I am taking out 25% from duty cycle. Actual duty cycle with these injectors ends up at 63%.

hrk

 

that's one of the nicest torque curves I've seen from a miata... excellent job dude.

 

63%! wow. my 450s are at nearly 90% with a 1.6 at 12psi. redline, 11.8:1 AFR

amazing what a few pounds of boost will do...

 

I would like to see what this puppy does on 15psi. See if the torque holds to redline.

 

Maybe later Andy,

Now I get myself used to 9 psi and when I do I can add more.

hrk

 

Im just power hungry, dont mind me

 

Blatant misuse of timesheets:
Here is one from Sunday race at Road Atlanta
http://www.texicanracing.com/nasatx/...h/scan0018.jpg

1:34.814 around Road Atlanta makes average speed to 96 mph.

Very happy with results. The RX-7 finishing 1.1 seconds in front passed several people (including me) under yellow flag and got disqualified.

Towards the end of the race the water temp crept up to 220 F and there was some sputtering, took an easier lap to cool it down and went off again once temps were at 200 and the car was fine again to be pushed.
I need to add another radiator to the trunk of the car, fed by rear opening of the head.

Here is link to datalog from accelerating from standing start:
http://russmarshall.com/v/cars/cmc7/...geViewsIndex=1

hrk

 

Congrats HRK! Time to find a bigger challenge if you're leading and winning your class already? I think the bigger victory is to put together your turbo kit and race successfully so soon w/o major issues. What are you using for a rad? - rob