1995 Mustang Cobra tip-in throttle bog with Shiftmasters Tuner Board

[Jer]

Anyone knowledgeable on ’95 ECMs? I’ve got a weird tip in throttle bog going on. Car runs great otherwise.

I have a 95 Cobra with a 410 stroker, 226/226 duration, .515 lift flat tappet cam, ported World Products heads, TF intake, full exhaust, etc.

I purchased this car as-built and the previous owner did all the upgrades. He paid a local dyno shop to tune it a few years ago. I saw the receipt and they used a Shiftmasters Tuner Board piggyback. I have tried a couple times to contact Shiftmasters and they don’t return my emails. My guess is they may not be in business anymore.

Anyway, my car runs great but has a weird bog or flat spot when I tip in the throttle really quick. It will actually pop/backfire through the exhaust if I push the throttle too fast. I read these cars have a factory throttle tip in retard so maybe that is the problem and the dyno shop didn’t adjust this correctly or perhaps the Tuner Board isn’t that sophisticated? I don’t want to take it back to that dyno shop as I saw the bill and they charged the previous owner $1,600 to tune it (including the Tuner Board). Seems a bit steep for a dyno tune and computer.

Does this bog/flat spot sound like it could be tuned out with the Anderson Ford Motorsport PMS? Could I just plug it in and keep my old piggyback Tuner Board and just adjust stuff? I hate to mess with it and make it worse but I don’t really want to take it to that shop and get fleeced.

Should I just get a legitimate dyno tune someplace else? The car really runs great except for that weird bog. Could it be something else? I am used to more old school engines and the bog seems to me like if you had the wrong springs in the mechanical advance. Then, I read about the factory tip in retard programmed into these ECMs and figured that may be the case, but that is just a wild guess.

Any recommendations?

 

[greenlantern]

Well for starters I don't recommend running two seperate piggy back systems. In fact I don't think either piggyback is gonna bring that combo undercontrol. $1600 bucks for a tune? Thats insanity, especially seeing as how the car still doesn't run right.

I think a tweecer is probably gonna be your best bet. And try to hook up with someone who knows how to use it. Your right about the 94-95 EEC's there a pain.

 

[final5-0]

I could be way off base here but I wanna associate that word "Shiftmaster"
with one of the first self tuning interfaces that hit the market and it was
called ... EECTuner.

A whole lot like the Tweecer when you get right down to it as far as tuning
is concerned. It didn't have anywhere near the datalogging capabilities
as the Tweecer however.

Whether I'm right or wrong about the above .............

I don't know how I can help you other than say I don't see how the tip
in spark retard would be causing that nasty bog.

I'd think if that method of tuning you now have has become obsolete
you would need to start over with a Self or Pro Tune.

Many here have done well with the PMS if you wanna do the self tune thing.

Good Luck

Grady

 

[Jer]

Thanks for the advice. That Shiftmasters tune was done back in 2003 or so. Shiftmasters web site doesn't look to up to date.

Subsequent to my post the previous owner told me there was no bog when he had the car. So that would suggest the tune may be on base as I haven't done any mods.

He suggested going through the normal stuff like ignition tune up, MAF, throttle body, TPS, etc. I did clean the MAF and throttle body but haven't checked the TPS.

I will sort through all of this stuff first before messing with the tune. The car does run really hard, just that annoying bog.