Switched back to stock paramaters over the weekend and noticed my brake pedal was a bit more solid feeling. Switched back to my 89 perf tune and the pedal went back to feeling a bit soft.
Does this make sense to anyone? Could it be a result of more or less vacuum being made with the perf tune? Or am I just tripp'n?

Thanks
Shane

 

What tunes are you running?

 

tunes do not affect brake pedal feel

 

Troyer.

 

The more percent the throttle blade is open the less vacuum, is the idle raised on the tune in question?

 

But, if you could actually "feel" it, wouldn't the vacuum loss be more than what you'd get from just an increased idle speed? Any possibility of a vacuum leak?

I'm with OCP on this, I don't see how a tune can effect your brake "feel".

- Jack

 

It leaks only with the performance tune?

Maybe the tune changes the trans to unlocking sooner and down shift later and would equate to more braking needed? There can be many possibilities, maybe VCT tables have been changed? I don't know what changes are made to the tune, but I wouldn't rule out that it cannot be the tune.

 

I know, it sounded pretty flimsy when I typed it, but I was thinking, oh hell, who knows what I was thinking? :o

But he's describing a "mushy" feel to the braking, and that would rule out what you said about the effect of the trans unlocking sooner..., too, wouldn't it?

A "mushy" feel is usually due to a leaky master cylinder in my book. And, that has nothing to do with the tune at all.

Interestingly, I had a "mushy" brake feel on my car once. But it would only happen now and then. 99.9% of the time it was fine. Then it started getting worse. Master cylinder replacement fixed it.

- Jack

 

I'll gather some more data on my next tank of gas.

I'll check when I switch tunes but I don't think it is.

I stated I was using the 89 perf tune in my original post but the more I think about I was probably using the 89 tow tune. Anyways I'll check all four tunes and see if I can nail down the details.

I appreciate all the input!