I have a Vortech and some other mods listed below........When i rev out at the top of 4th gear it sounds like the car is misfiring like a waaahhh pah pah pah then it catches again........it started at 4th, and didnt bother me much, now i noticed it at the top of 3rd and 4th......I cant tell if its the gaping with my plugs, or the timing..... or am i short on fuel up top and thats my problem i need bigger injectors?..Any suggestions or help would be much appreciated..

Thanks

 

At what rpm are you talking about...6800rpm ? If so , you are hitting the rev limiter

 

Nahh my rev limiter is set at 7200........... I hear that at around 6000, dont get a chance to really look when im flooring it in 3rd gear, or 4th, just know its at the top for a second then it smooths out , then i have to shift

 

When my Vortech was first installed it did the same thing one morning, but on the low end. it would not rev past 2500. It appeared to be hitting the rev limiter.I turned the car off and then switched the ignition on and off 3 time without starting the engine , this must have reset the split second box, it only stumbled one other time that week but it was at the top of 3rd gear. Anyways Vortech sent me another split second stand alone box without any questions or hassles. No problems ever since !

 

If its fuel related , the FMU might be going bad . And like yama1 said..it could be the SS box . How long have you had the kit installed ? If you had a shop do the install , take it to them , they can check it out for you .
But I wouldnt go WOT till you find out . No sense in hurting the motor .

 

I have had the kit on for about 7K miles, its been real good also... I live far from the shop that i had the instal at, Im in NY they are in MD (AAM), ill just give them a call and vortech a call right afer i guess.... Just trying to get an idea of what kind of problem it is, maybe some one will hit it on the head........

 

Did you put new plugs when they did the install. Could be bad or dirty plugs.. Check them out first..

 

Yea, i did put new plugs in when i got the kit installed. I called AAM and the had mentioned trying new spark plugs and they suggested NGK's and have them gapped at .035. I am going to try that and see how the car runs.

 

If you mean the factory "rev-limiter", you are really referring to when the shift light is set to flash and Boog is most likely correct.

 

I believe he had the AAM flash that raised the rev limit to 7200 RPM

 

Trust me i know how to drive my car, and i am 1000% sure at 5800-6000 i am not hitting my 7200 rev limiter, to be honest, during a burnout i have reved my car out to 7400, the SAFC tachs your highest RPM so how accurate it is i dont know, but thats what it recorded, also like i said the power band smoothes out after the misfire...............I am pretty sure and hoping it is my spark plugs because this is a progressing problem.... it started at the top of 4th and progressed to the top of 3rd and 4th. When i have time next week i am going to change them and see what happens.