Hello, Im new to the website after my recent purchase of a 91 Camaro Rs with the tbi 305.I have just installed a 4.10 gear, eaton posi, moser axles, and some dot slicks.Went to the track last week and was running 11.30 to 11.60 1/8 mile with the old 2.73 gear.No tires slipping but it was very inconsistent down track.Im hoping this gear will help some but my true question is...Can there be something else causing the inconsistency, my engine temp was exactly the same every pass...160.Could it be something with the computer...smog system etc...All information is greatly appreciated.Im thinking a Hypertech chip may help??
Jimmie Barrett

 

There are a couple of things that can cause inconsistency. The ECM does a forced knock test which adds spark timing. But if the forced knock test isn't run, then PE spark isn't added. There is also the BLM learning which can cause the AFR at WOT to vary.

If you are getting into mod's the best bet to to include tuning of the ECM. That is by doing it yourself. The learning curve is a little steep at first. But once you get going it really makes a difference.

RBob.

 

I completely agree with what RBob said, for any serious consistency a custom tune will be a must.

Also, don't overlook the transmission. The sloppy shifting of the stock trans will kill any chance of having a consistent car. Best bet is to install a shift kit and heavy duty trans cooler. Varying fluid temps play a big role as well.

Forget the Hypertech junk.

 

I believe I have found an answer, 355 sbc carburated with the help of the tbi to carb conversion thread from this site.I have also found a built 700r4 with a 2500 converter.Speaking of converters, is it normal for the stock converter to only stall to about 1000 rpm before pushing the car.One other question I had on my conversion...I know this is the wrong thread but will the fuel pump run without seeing oil pressure or will I need to use the existing oil pressure switch on the older 350 sbc block?
Thanks for all your help
Jimmie Barrett