here's a copy of my dyno sheet:

 

Looks pretty lean... Did you track EGT and/or fuel pressure? I'd be careful...

 

Well there it is to all you naysayers, 427rwhps

 

Well, here is my dyno run at 2psi.

http://www.datapathusa.com/scott/dyno.html

 

lol. My 865 was in vacuum still, no boost!

-Ethan

 

heheh

 

Well there is the proof. That was really 8 psi? It is interesting about the compression bit - what is it at about 9.4:1 with the tt head gasket as opposed to the RIdeal 3mm for 8.5:1 or equivalent? My question is what is the compression I guess?

Scott, what gives cause for concern on the a/f plot there? I am not so experienced but I see the #5 run at 14.8 if I'm reading correctly and that is too lean? Educate me. I thought the ratio could be taken as far as 11.

 

Air fuel ratios around 14.7:1 are considered "stoichiometric" and generally produce the most complete combustion with low emmissions. N/A vehicles can be tuned near this A/F ratio---say 13.5:1 and gain some power. Typical OEM ECUs on NA vehicles will put the a/f ratio at 10-11:1, giving up some power for reliability and a safety margin in the event that operating conditions cause the a/f to wander a bit.

Forced induction vehicles rely on extra fuel to cool the intake charge. Its cooled by the un-burned fuel and By-products of incomplete combustion. Running extra fuel lowers EGTs and saves your engine parts from increased thermal stress from possible detonation. Running stoich (14.7:1) can cause very high EGTs, and detonation under heavy boost.

Yes 11.1 is a good safe a/f ratio. The higher the number the leaner (and less safe).

On the flip side, running 8:1 is bad too, because raw fuel will wash the oil off the cylinder walls and exaggerate ring wear.

 

Well thanks! I had it backwards in my head. 14.7 is stoich, so I figured the lower the number the less fuel that is present but it is opposite and makes sense when I actually think about it. My bad.

 

I'm not trying to be a smart-***, but when you make anything close to any real power on a 2jz, you might have room to talk. I don't doubt at all that Wayne made 427rwhp, but it wasnt on 8psi, as Scott and Ethan's sarcasm was hinting at.

Wayne, you may have had a vacuum line pop off, boost controller malfunction, or dyno error. I've seen the latter possiblilty with auto trannys slipping an giving erroneous readings and seeing how your tranny is stock and you had just made multiple dyno pulls, that is a distinct possiblity. Either way, you may have thought you had your boost at 8psi, but I assure you, it wasn't at 8psi on that run. The middle two runs look about right for 8psi. Do you have the torque figures on those runs?

As far as your A/F goes, that is WAYYYYYYY to lean. IMO, you never want to run over 12.5 on the street under load, which usually means 12 to 1 on the dyno since there will be less load. It is only a matter of time before you melt something with those A/F's.

 

Scott, you should've been a teacher, perfect explanations of stoich and ring wash, and yeah, if he running stoich on a turbo car, just asking for a hole in a piston.....

 

I agree, I don't doubt that it made the power, I just doubt it did it at 8psi.... Not on a 60-1 anyways, and especially not with lowered compression.

-Ethan

 

We know it was running lean. After we finished dynoing the car we richened it up on the topend. After i get the tranny done i'll be back at the dyno to do a full tuning across the board at higher psi.

 

i dont care how many PSI's, I just want to know what you paid

 

Whats up Mitsu....... looking for a SC huh ... join the crowd..