I have a '91 T/A 5.0, auto and 2.73's. In a race tonight, above 100mph while at WOT my car sputtered and felt like it hit a rev limiter. Is this the feeling of the dreaded "can't shift into 4th at WOT" feeling? Or is it a rev-limiter. I didn't even know 3rd gens had them if it was.

So how do I fix this or go above 105-or-whatever-mph?

 

With those gears, you should be past 110-120mph when shifting to 4th.
You may have a limiter on it, as there is a limiter in the prom, but I haven't come across any TPI cars that had the limiter set low enough for the car to hit it.
here is a video of my 88 when it was an Auto with 3.73 gears in it, stock tranny that upshifts to 4th in WOT.
http://www.transamws6.com/video/130mph.wmv
(please, no comments on the music that is playing )

 

Now that I think about it, this happened on the dyno in 3rd as well. My brain is fried right now, what does that mean?

Btw, thanks Zeph.

 

I would find someone local with an eeprom reader and the adaptor to read a stock memcal and see whats in the program and if the limiter is set low.

 

Maybe someones messed with your limiter and set it lower for whatever stupid reason, or maybe your fuel system cant keep up?


Zepher: Holy fak that car pulls, was that with the nos?

Oh BTW nice music

 

Nope, stock TPI with an Air filter.

 

damn, my cars gutless...


So, as for your car cutting out. What RPM does this happen at? AFAIK if you hit a rev or speed limiter the ECM cuts fuel until you drop below the limit, so your engine will feel like the keys been turned off till you slow down.

 

I did it again tonight and it's at 110mph. The feeling isn't what you described, more like a 3-loud-rapid-revs, not the car being like it's turned off.

 

It's in the PROM and it set at 125mph:

AXXF bin: 125.00 / MPH Fuel Cut Off Vehicle Speed

 

Then what is happening at 110?

 

Who knows. If you want to be sure, take the metal accesscover on your ECM and look at the 4 letter code on the silver sticker on the top of the blue MEM-CAL cover. It should say AXXF for you car. This is the same MEM-CAL my 92 GTA had stock and I read it into my computer. It was set to 125mph. I can post a computer screen shot for you if you want more proof. I even verified it against a stock AXXF bin I downloaded from the internet and it's identical.

Either your MEM-CAL is not the AXXF, or it's a mechanical problem with your F.I. or sensors...

 

Or maybe his speedo is showing 110 and the ecm is reading 125.