Dyno question

[daviss]

How does Alky affect the wideband readings on the dyno? I made a couple of pulls the other night and the A/F took a huge dive when the meth came on. There was no knock and it looked on the DS that everything was in order. 02's were about 800 on the DS. We decided not to use the wideband because it contradicted the DS readings. Car felt strong all three pulls.

Pulls were @ 20 psi with Razor's meth kit set @ factory settings. Made 375hp and 420ft-lbs. Not too bad for the first time on the roller. Three pulls really isn't enough to get this thing tuned right. Should be a lot left in it. I'll give free beer to anyone who can tune this thing. (After it's tuned)

 

[Reginald West]

Its been my experince that when the meth comes on the car gets real fat.In fact I had to take 20 percent out the fuel map on both of my cars when meth came to get them to perform right.

REG

 

[2QUIK6]

What I observed on the dyno in regards to the stock O2 reading on DS was that it was very low, indicating it was very lean, yet the WB on the dyno said 11.5. My DS was showing o2 of around 690-710mv.
I was getting no knock and decided the WB was right and my o2 before were in the 780-800 range.
After the dyno pulls, put it on the street, and the o2 readings were back at 780-800mv... I suppose it has something to do with the real load on the engine instead of the dyno load which is not quite the same as the real weight of the car, I'm guessing the dyno roller resistance is less than the real rolling weight of the car..

 

[Roc87]

With the Methanol, My a/f wouldn't get any richer than 12:1. On the first pull it was around 12.8:1 and I turned up the WOT Fuel in the translator, made another pull and it was around 12.4/12.5:1, made another adjustment and got it to 12.1:1, and it seemed WAY too rich, when I let off, it sounded like a shotgun went off. Don't have DS any more, but the scanmaster showed around 750mv on the final pull.

What size turbo are you running?

 

[daviss]

I would have put it on the street but it started snowing while I was on the rollers. Made for a nice ride home.

It's a TE-60 turbo. I'm not unhappy with the results, I just want to make sure I don't blow a head gasket. I'll go to the track when it opens and tune there. I actually turned down the boost for the last pulls to make sure I didn't break it and get stranded at the dyno with snow piling up.

I wish I had a scanner to post the graph. The A/F is all over the place.