WheelmanZ28

I recently had my car custom programmed after the Hot Cam install. The person who tuned it adjusted the idle, shift points, gears, etc. But i also noticed he raised my rev limit to about 6700 RPM. The first time i hit WOT and hit the high RPMs i was freaked out cuz it sounded like my engine was about to come apart. For the most part the car runs great. However, when I'm at WOT and i hit these high RPMs, it almost seems like im losing A LOT of power. As soon as i pass 6000 RPM, the car seems to stop accelerating and just coasts until it shifts. Was my programming screwed up? I thought this cam mad good power in the upper RPMs? or am i wrong? thanx for the help.

1997rblckSS

6700rpms? man that is high..
I don't have programming, but I know that the cam is suppost to make power up to 6500 rpm's...but I shift right at 6000rpm's and it seems to like it right there...Bearing are going to start to wear fast shifting at that high of rpms's. IMO.

hairbear21

You're above the power curve and you are losing power at that RPM. I would lower it to about 6 grand and you shouldn't "nose over" like that.

WheelmanZ28

yea, i would like to have it turned down. but i got the tuning free as kind of a one shot deal. Is there anyway to turn the rev limit down? i still have my hypertech crap, but i'd like to sell it rather than use it just to turn my rev limit down.

hairbear21

The best thing to do in your case is sell the Hyperturd and use the cash to buy an interface cable and LT1_Edit or TunerCat or something along those lines so that you will be able to set the shift points yourself

FireAm94

My hotcam fell off pretty badly after 6k before I intalled the blower...if that helps any.

Joe

WheelmanZ28

hmmmmm, well a blower is too rich for my blood right now.

But now I'm guessing this could mean i need more fuel up top.

FireAm94

I think it's just the powerband of the hotcam if u ask me.

Joe

mkent

this does not have to do completely with this post but i was wondering what the stock shift points are on these cars and if there is a better RPM to shift at. my car is entirely stock and had a recent tune-up, but it does seem like it should shift a little bit sooner than what it does. it's like it gets up near redline and runs out of power until it shifts. sounds kind of like wheelmanz28's problem except not nearly as noticable.
maybe this is normal, i'm a former M6 driver so i'm used to it shifting when i want it to shift rather than when the computer shifts it.

hairbear21

On a stock Z28, the shift points should be around 5800 RPM at WOT. If you are losing power before that, you may have an underlygin problem. Also, before you do anything else, at least go to 3.23 gears! They are perfectly tame at interstate speeds, and the car will be more responsive to mods that you do to it.

mkent

i think it's just that 1-2 shift is too smooth for my liking...i liked the "grab second, kick sideways" action of my M6 tranny. but with those 2.73's and A4 once you hit 50-55mph it pulls harder than any non-bigblock car i've ridden in. also the 2-3 shift is much firmer than the 1-2 shift in my opinion.
ii've thought about switchin to 3.42's out of my old car but i'm afraid traction will be too much of an issue. it's perfect with the 2.73's...but then again the car is slow off the line.
maybe a torque converter will help me?...hmmm...

FireAm94

When I had my A4 with the hotcam, headers, and other boltons with 3.73's my best 60ft. with yokohama avs intermediates (street tires that aren't drag radials) was 1.86. I don't see any traction problems. That was with stock control arms shocks and everything suspension wise.

Joe

mkent

that's a good 60'. what kinda ET did you end up running, and mph?
also, what kind of gas mileage do you get with that set up? i'd like to do a mild cam, headers, TC and possibly gears in the next summer or two. but gas mileage is an issue right now for me, i need to keep it around stock gas mileage.
thanks

FireAm94

I don't remember gas mileage but it was pretty good....probably 24 or so highway. BTW...I had a b&m 3000 stall also, af far as the e/t went....it was an 8.41 @85 mph. That was with shorty edelbrock headers, transdapt cold air, 52mm throttlebody (lots better throttle response) too.

Joe

WheelmanZ28

When my car was programmed, i was told he set the shift points for the stall that i was planning to get. I planned on going with the vigilante 2800 stall. If i get this torque converter, will everything be ok then with the programming and the shift points?