Max and I went to the dyno today. After 12 passes I was able to get Max 3 HP (197.3HP & 134.6TQ)and his A/F ratio was pretty smooth all the way across. It still needs a bit more tweeking, especialy below 6k RPMs. We would have stayed on longer, but there were people waiting for apointments to get on the rollers. It seemed as though the ECM was fighting some of our changes and kept trying to richen the mixture. I think it might have been due to the temperature rising as we were going along.

I also did some tuning to mine, and ended up with a disapointing 190HP but that was up from a VERY disapointing 183. Again, the ECM seemed to be fighting us a bit. I am going to try to get the OBD2 reader so we can try to make the runs more uniform as far as temp goes. We did notice a fluctuation in temp according to the shop owners laser thermometer, but it was unavoidable. I am making an appointment for next Saturday morning for at least one more hour to get this straightened out. I am going to examine and probably replace the plugs as well, as I think that may be an issue like Ben had.

I did get a pass in with the nitrous, a wet Nitrous Express 50 shot. Final numbers with the N20 were 237.5HP & 168.8TQ. The plot for that is below Max's. As you can see the wet setup runs nice and rich which is exactly how I want it with the juice.


Max's Plot:


Jeff's Nitrous Run Plot:

 

Hey Jeff, thanks for sharing.

And yeah...get the plugs checked. Your #'s w/o juice are too low...

 

It's been bothering me all day now. I am going to go get a set tomorrow and install them.

 

It is possible that this dyno runs low. Only way to know this is to get a pre-dynoed car on those rollers so to say.........yea it's running low.

As for the temps.............you NEED a ODB scanner to get temps. You want to keep VERY consistant temps. Probably dead on or within 5 degrees. I think 190 is where we ran our cars. Though you don't want to tune at to high of a temp because at lower temps that A/F might not be the same. It's where a true tuner will come into their own..............instead of us hacks!

 

LOL, you are right, we need the OBD scanner. However, I refuse to pay some guy (who most likely learned to tune the same way we do, by trial and error) an obscene ammount of money to say "hey, your running 11:1 at about 5000RPM, lets take out some fuel". I think our money is much better spent on the OBD scanners and other needed equipment which can be used again and again. Thats where my money will go anyway.

It is also possible that the dyno you guys ran on was using different correction factors than this one. I know this dynojet is only about a year old and is very well maintained. We had pics of the shop, which is impressive, but my battery died and the memory crapped out losing them all.

A highlight of the afternoon was the old school Supra putting down WELL over 300HP and almost 400TQ to the wheels with some very minor tuning done to it. You just can't beat forced induction for tunability.

 

see the little break at about 7.5k we had the same issue until we changed the line on the plug wire from 1 to 3 - Jim is right we were running right at 190 degress (jim was consistanly lower because of his mugen t-stat and switch - 180 i think)

something must be off as i was pulling 207 and max and i have pretty much the same set-up

 

[QUOTE]Originally posted by Bass
[B]see the little break at about 7.5k we had the same issue until we changed the line on the plug wire from 1 to 3 - Jim is right we were running right at 190 degress (jim was consistanly lower because of his mugen t-stat and switch - 180 i think)

 

You can think that.... if it makes you feel better

But guys, remember... these are two different dyno facilities. The corrections that they computer can make are never 100% right.

Jeff, I wish I had the time to go down there with you guys... I know I could've helped you out. When we did the other cars at NE Dyno. We had my OBD reader there, and by the third car we tuned, we had it down pretty good that the following cars where on the dyno for 1/2 the time the first car was.

But... as I'm not very familar with the "juice", those air fuel mixtures look dangerously too high AND lean pre-vtec. But what the hell do I know

Let me know when the next time you tune. And I will TRY to be down there. [mumble to myself]Freaking work [/mumble to myself]

 

Glen, I will be going back next Saturday morning. Let me know if you can make it. As far as tuning for the N20, there isn't any way to do it. There are jets for the fuel and N20 that are used. For a 50HP shot, they specify which ones to use, no adjusting. I agree that it did look lean before I flipped the switch, which is an issue with the VAFC settings and why they have all been put back to 0 for now. If anything I would rather be runnng a bit richer when using the N20 to prevent any detonation. I think a set of plugs one step colder will make a difference with the N20. I'm also picking up a set of NGK 6564 plugs and will try them.

The dip you see down to 10:1 for a brief second is because when you don't purge the line prior to flipping the switch, it takes a split second for the pure N20 to make it's way through the line, so fuel is being added before the liquid nitrous makes its way through. This is not dangerous at all, however it does rob a small bit of performance, but will be taken care of on Thursday when my purge kit arrives

Give me a call if you are available. thanks

 

I will plan on being there Saturday. But if my wonderful job has me still overloaded, I'll let you know.

Put it this way... where do you think I would rather be