Hesitant rev

[kfellers]

Help, got my 3:73's put in today by the local Mustang guru, he drove the car afterwards and said it doesn't quite run like it should...should have a little more umph! He (I have for a long time) noticed that when you give it a quick rev, it seems to hesitate just for an instant before revving up. Almost like it has to take a gulp of air before any engine response, if that makes any sense.

I have an older ('93) Superchip "B" chip in it, could this chip be a piece of crap and not have advanced the timing enough and screwing up the timing? Mechanic said it may just need the timing bumped up a bit, what do ya'll think
Any help would be appreciated!

A little more info on the car, it's an 88GT see sig for mods..not much a couple of bolt-ons, still speed density.

 

[90mustangGT]

I would check the timing and at first set it to 10*BTC and then check the TPS voltage, should be with key on engine off be around .99 volts. Then if that's good then I would do a TPS sweep and be sure the voltage smoothly and consistantly increases in voltage as the throttle is opened. Then if that's all good I would check the connections to the PCM.

 

[HISSIN50]

So a MAF chip works alright in a SD car?

I like Jason's idea with the timing and TPS checking. I would also check the manifold vac. WIth a SD set-up, one likes to see nearly 20" hg at warm idle.

Any codes? You will need a code reader or test light to retrieve them since a SD car has no functional CEL.

Good luck.