Hi everyone, we took the Scarboro Mazda Racing RX-7 back to the dyno on May 26 to set the air/fuel ratio as per Mazda Motorsports Development (Mazdaspeed) specs. Getting the air/fuel ratio rear 13:1 (12.81) we developed 230rwhp@9200 rpm and 145 ftlbs of torque@7100 rpm! We were really happy with the results, and could never have achieved those results by seat of the pants or looking at spark plugs style of tuning. Dyno tuning is fairly inexpensive at DynoJet services on Nantucket Dr in Scarborough! If your car has adjustablility you should get to a dyno and see the results!

 

Very nice!! That's N/A right? Very impressive!!

What did it cost to get the tuning done per hour? Did they let you do all the driving on the dyno? Did you use a wideband to get those A/F numbers?

Sorry for all the questions, just.....curious

 

I agree 100000%. What did you tune with?

 

All Jeff at Dynopower does is set up the dyno, install the air/fuel sensor in the exhaust pipe and run the car on the dyno at the rpm range you ask him to. We did our own jetting on the carb. (yes i have a holley 650 double pumper, the carbs that dont work right!) You can pay per hour if you want or he charged us $ 50.00 for 2 pulls with the air/fuel. Most dyno guys arent tuners, some can tune if you have a piston engine, but I havent heard of or met ANY rotary guys that dyno tune.

 

And yes, naturally aspirated all the way!

 

So was the air/fuel senor just something that they stuck through the back of the exhaust or did it acually get put into a bung on the header/downpipe?
Oh btw, what does he charge per hour?

 

Its the same sensor as they use when they do an emission test, so I think it is pretty accurate. I think he charges about $100.00 per hour, you can call Jeff directly at 416-752-3966.

 

The exhaust tip sensor can only be used when there is no cat installed. Otherwise you'll need to have a bung prior to the cat. I have been talking to a few dyno shops in the past week to organize a dyno day for the RX Club of Ontario. We will probably announce the date on Sunday evening.


Those are some impressive N/A numbers, congrats.

 

I was just talking to Jeff at the dyno, he has the Mini Club there today. He said the air/fuel reading at the tail pipe is about 1/2 a percent leaner than after the header. I dont know if thats true, but the Mini guys seemed to confirm that. The supercharged, chipped, cold air, underdrive pulley etc best pull was about 190H.P.
n/a 13b's rule!

 

This car has a ton of power out of an N/A. And it is running a 650 Holley Double Pumper. I wonder what it would do with programable fuel injection.

Way to go Al.

 

Sorry to scab your post Al, but I can't start a new thread. It does involve you and Scarboro Mazda though.