My Z28 is real strong through first and second, but seems to fall flat on it's face in third, untill the rpm's get back up. The car is setup as follows:

All stock internals 1986 305 TPI
700r4 with corvette servo (5500rpm shifts)
2200 TCI converter
2.73 open rear

Now I am upgrading to a 3.27 9 bolt rear because the 2.73 is noisey and on it's way out. Will the higher gear ratio help with this, or am I stuck with this till I replace the motor or cam?

Thanks,
-Jim

 

anyone?

 

yeah i am going to say that the new ratio will help get up to speed quicker and will alittle better up top.

with my 3.23 stock gears first and second oull pretty good and then when in drive i simply dont have the horsepower and the car starts to slow down (pull wise).

all in all the new rear ratio is going to help your quarter mile track times and be better from stop light to stop light.

 

3 problems (assuming no mechanical/electrical problems):

1. Weak engine.
2. Poor gearing.
3. Heavy car.

Gearing up to a 3.27 will help a small amount. You'll notice it more through first and second than in third though. Weight reduction will help, but not much.

The biggest improvement would be seen from full exhaust and a cam swap.

 

That's what I figured from the cam swap I allready have the 3" flowmaster and am considering the Hooker 2055 headers. I have the summit g5000 cam sitting here but the motor has two cyl's that the compression is low in, so I'm probably not going to put it in and just build a 350 as a replacement.

It's really right after the shift that it falls it on it's face, after the rpms get back up it starts pulling strong again.

I removed the a/c and heater (car isn't drivin year round and is my project car) and it has no big stereo equipment or anything in it so it's around the stock weight, maybe less here's all the mods that are on the car right now (more waiting to get put on)

MSD 6A
Accel 8.8mm wires
March Pulleys (crank/alt/waterpump/ps)
Flowmaster 3" cat back
Dynomax superconverter 3"
Built 700r4 with corvette servo
TCI 2200 stall
Crane ps-91 coil
Ac Rapidfires
Fluidampr Balancer
Relocated IAT

 

If it's just a momentary bog you might try posting this over on the TPI board as there's a good chance it's fuel related. Have you tried monitoring fuel pressure?

 

It's not a bog it just feels like it fell out of it's power range, and i was wondering if the gears would make it get back into it's range quicker, it used to bog alot but i took care of that, ended up being the pickup coil in the ignition