• 9 -------------------- Date: Sun, 6 Aug 2000 18:29:00 -0400
  From: "NickG" <nikog_at_MediaOne.net>
  Subject: stage 1 turbo dyno results
  

I made a couple of passes with my car on the dyno today. Both runs produced the same hp, and the peak torque was within 4ft/lbs or each other. Results:

Max Power: 280hp _at_ 5500rpm
Max Torque: 277 ft/lb _at_ 4500rpm

The link to the graph is:

http://www.pompano.net/~nikog/pics/dynorun1.jpg

Details:

'95 M3 5-speed
AA Stage 1 turbo kit
30lb injectors
custom air box/heat shield
6psi base boost setting, but boost started dropping off to 4psi above 5000rpm (due to wastegate setting/design) run(s) made in 3rd gear
2 1/2" downpipe, high-flow cat, stock muffler custom tuned chip (by me)

I can't wait to see the results after I get the boost stable at 7psi all the way to redline. Maybe 300rwhp??

Enjoy :)
Nick

• 10 -------------------- Date: Sun, 6 Aug 2000 15:52:24 -0700 (PDT)
  From: Matt Henson <hensonator_at_yahoo.com>
  Subject: Re: [BigBoostGruppe] stage 1 turbo dyno results
  

Hi Nick,
Wow.. here are a few thoughts..

1. Your torque curve..its's flat!
2. I'm a little skeptical that you're only making 4PSI at the HP peak. Here's why. If you take a stock M3 and dyno it it will make around 200RWHP. Given that the MAP is 14PSI absolute, that's 14.28 HP/PSI. Now, take a nicely tuned NA M3 with a CAIS. It will have about 14.5 PSI MAP. It will make, say 225RWHP or 15.5 HP/PSI.

Your car is making 280RWHP at 18.5PSI. That's 15.1HP/PSI. Which is better than stock. And almost as effieient as a tuned NA car. I'm not saying that this isn't possible, it's just amazing.

Normally you'd expect the turbo motor's pressure-power efficiency to be much lower than the stock NA one. For example, AA's example Stage 1 on the site makes 295_at_21.5PSI absolute or 13.7HP/PSI. I'm not sure what my car did since the boost also dropped off because the BC wasn't set up correctly. But I expect it to be worse than AA's.

3) If you are really only running 4PSI and you can maintain, say, 15.0 HP/PSI then you'd make around 320RWHP. In reality, I'll bet that the efficiency drops off a lot above 4PSI as the timing retards to deal with detonation. But 300RWHP should be within reach. Ironically, 320RWHP is 380 at the crank, which is that Mitsu says that our turbo can support.

4) It will be interesting to see the EGO of your engine at some point.

5) That torque curve sure is flat. :-).

Good Job,
Matt