High RPM "studder"
Thread Starter
Burning Brakes
Joined: Apr 2004
Posts: 859
Likes: 7
From: Spring Texas
St. Jude Donor '05
High RPM "studder"
Recently I installed a Super Ram, 1.6 RR's and a custom chip -
Before the mods the car struggled to RPM past 4500 rpm, after the install and before the chip the car would climb to 5500 rpm with no problem, but as soon as it hit 5500, the car would act like it hit a rev limiter...
The car does have MSD 8.5 wires and a Accel 300+, I checked the limiter on the 300+ and it is set to max or "no limiter" - So I don't think it's from the box...
I figured t he custom chip would solve the problem, but had no effect on the studder problem...
The motor has 90k+ miles on it - could it be a valve spring issue (they are stock) or is it something else?
BTW the car is a '90 L98 with and Automatic and 2:73 gears - I have other mods done to the car, but I don't think they are the problem..
But just to make it a little more simple to help me out, here are the other mods - FMS 24# Injectors, SR, 52mm TB, AFPR, 8.5 MSD wires, MSD cap & rotor, Accel 300+ w/ coil, underdrive pullies, LT headers, Corsa LT1 exhasut, No cats or Emission stuff, 1.6 RR's, Haedened push rods, cut air box lid, 160deg stat, K&N filter & custom chip with all this information..
I have a D44 w/ 3.45's on the way, but I would like to get a handle on this before I start the next upgrade....
Any help would be great!
Before the mods the car struggled to RPM past 4500 rpm, after the install and before the chip the car would climb to 5500 rpm with no problem, but as soon as it hit 5500, the car would act like it hit a rev limiter...
The car does have MSD 8.5 wires and a Accel 300+, I checked the limiter on the 300+ and it is set to max or "no limiter" - So I don't think it's from the box...
I figured t he custom chip would solve the problem, but had no effect on the studder problem...
The motor has 90k+ miles on it - could it be a valve spring issue (they are stock) or is it something else?
BTW the car is a '90 L98 with and Automatic and 2:73 gears - I have other mods done to the car, but I don't think they are the problem..
But just to make it a little more simple to help me out, here are the other mods - FMS 24# Injectors, SR, 52mm TB, AFPR, 8.5 MSD wires, MSD cap & rotor, Accel 300+ w/ coil, underdrive pullies, LT headers, Corsa LT1 exhasut, No cats or Emission stuff, 1.6 RR's, Haedened push rods, cut air box lid, 160deg stat, K&N filter & custom chip with all this information..
I have a D44 w/ 3.45's on the way, but I would like to get a handle on this before I start the next upgrade....
Any help would be great!
Thread Starter
Burning Brakes
Joined: Apr 2004
Posts: 859
Likes: 7
From: Spring Texas
St. Jude Donor '05
Hey Alvin!
No, nothing as of yet - I'm planning on checking the fuel pressure this weekend - what #'s should I look for on the pressure?
I'll send you the results from the data log for you to take a look at as well!
No, nothing as of yet - I'm planning on checking the fuel pressure this weekend - what #'s should I look for on the pressure?
I'll send you the results from the data log for you to take a look at as well!
