redline with a 26 inch tire currently and only trapping 108??? something isn't right, I have 3.73's in my vert and on the motor it went 12.6 @108 and wasn't close to redline in 4th through the traps, now grant it I have a custom cam but rpm band was up to 6k iirc....I run a 275-40-17 on that car to and on my 85 with 3.73's and trapping 128 I'm close to redline on it with a 26 inch tire but I do have a little more rpm to work with then what A TFS-1 OFFERS...but still you should not be close to redline at 108 Imo..........what springs and heads are you using???

 

I thought i seemed off i wounder if the factory tach is that off?? but it doesnt feel like it.


springs idk, stock heads. the cam was installed buy previous owner he had the motor rebuilt in 2006.

 

stupid question does hp have anything to do with redlineand speed??? or does it only come down to rear end gearing and tire hight. sorry if this is a really stupid question

 

horsepower has nothing to do with RPM limitations. Its all about your valvetrain components and efficiency

My cams recommended "peak RPM" is 6800.

 

So when you guys say somethings wrong, are we think I have weak block or something???

 

no...just seems odd you are redlining at 108 with that set up...what is the rpm reading through the traps??

 

5700-6000 stock tach

 

does it feel like it's almost out of steam going through the traps??

 

YOu need to confirm your tach reading.

 

factory tack can be off as much as 800rpm at higher RPMs been a problem since the start of the 5.0s. get a good tack..