I searched and didn't find anything on this. I have 03 that I just had a Vortech S/C installed. It is putting out 350 rwph at 7# boost. Runs great in all ways except...when I shift in manual mode at WOT it misses like it would if I hit the rev limiter. I'm not hitting the rev limiter, since I drag race a lot and know how to avoid that. It will do the same thing in complete auto mode as well. So if I get on it it will cut out when I shift. I have been told that it is the tranny cuz I have drag raced it so much. I don't think so because it will turn 13.1 all day long with street tires and I'm shifting short (5100 rpm). To me it would seem that I would feel the tranny slipping and the the times would be much slower.

Anyone have any ideas? It seems as if the ECU is thinking it is at redline, but it isn't. And again I don't think the tranny is slipping and if it was it would feel like it was slipping instead of feeling like it has a miss at 5100 rpm.

It has the stock Vortech piggy back and stock ECU.

 

Mine did this as well when i put the greddy twins on.It seems that it will shift normally but it hits the rev limiter.I insalled as v/b and it shifts as soon as i shift it.

 

You need to upgrade your valvebody. I have a stock one I can sell you that you can send out to have modded.

 

That is probally mine.

 

Hmm, I am not having any issues like that. If I'm WOT in auto, it keeps going without a tic. Might have been the abuse from drag racing on the tranny.

 

I have the Stillen VB in it and it still does it.

 

That's what the shop that installed the S/C
thinks, but it doesn't slip. I did put a lot of 1/4 mile trips on the tranny when it was N/A though.

 

I know my shifts are slow, but it doesn't act as if it hit the rev limiter. I assume no slip light, but I wonder if it's ever so slightly slipping traction and reacting. Normal driving isn't causing this right?

 

Is it "missing" in each gear in both manual mode and full auto mode? Did the motor come out for any reason when you did the SC? Sounds pretty basic but have you checked the fluid level in the tranny lately? If you have dragged the car ALOT and since its an 03 it may be time for some new clutch packs.

 

I haven't had this problem at all and I drive almost exclusively in manual mode now that I have paddle shifters. The only problem I am running into is that especially with the extra power my transmission it exacerbated the problem with the slow shifting of the AT tranny. I have to shift at around 6,000 rpm so that my transmission with shift in time without me hitting the rev limiter.

 

Try changing out your fuild.

 

this acts exactly like I have hit the rev limiter. No slip light and TC off. Normal driving is very normal with no misses. Anything under 5k doe's not cause a miss/stutter. I can take off in 1st, hit second right away(4K) and it will hook up good enough to put down rubber for as long as it is WOT without the stutter.

It only happens above 5K while shifting manually at WOT.

 

fluid has under 400 miles on it. 7 passes at the drags and some racing myself fun, so it should be pretty fresh.

 

It is pretty normal for the engine to run up like that and was the first thing I thougt of, but it doesn't seem to be the case although this is the closest to describing what is happening. I have my shift light set for 5K right now and it will go up 500rpm between shifts, but that still is far from redline.

 

Motor didn't come out, fluids are good, it has been drag raced a lot, but before the S/C and shift kit it would shift very quickly, quick enough to chirp D/R's in third gear with a pretty stock engine. I have a 6MT rear end ratio.

 

OK folks Z Car Garage found out what the problem was. The Vortech piggyback had a corrupt program. It doesn't cut out at high rpms while shifting now. Back to the track to shave some tenths off my time.

 

Well its finally time you found out what the problem was.

 

good to hear. Really weird problem.