3000 or 4000 GSK ?

[JLewis]

I'm trying to decide which kit to get for my '98 5-speed. Right now I have a good plate, straight pipe and a cold air kit. Just installed my South Bend Con FE clutch a couple of days ago and my next mod is going to be govenor springs. Is there much performance difference between the two? (3000 vs. 4000) With the 4000 rpm kit do you need to change both the exhaust and intake valve springs to the heavy ones or just the exhaust valves? Also is it possible to float the valves with the 4000 kit if you were to just put your foot to the floor in a low gear and hold it there? In other words is there some sort of rev limit or is there a danger of reving too high and hurting the motor? Thanks.

 

[Pthomas]

I recomend the 4K with the 5sp

I ran the 3K springs for alittle over a year and just this year installed the baby springs or the 4k kit and even from 2000 to 3000 there is noticable difference. I diddnt change my valve springs right away but i never just held my foot to the floor to see if the valves float, i wouldnt recomend it. After watching the tach jump alot faster than before i finally installed all 12, 60lb springs. do it right the first time youll be much

 

[nfox]

gsk

I just installed a piers 3000rpm gsk in my 96 5. 9 cummins with a 5-speed and wow what a big difference!! You'll want to watch your egt's when you get in the higher rpm it will heat up fast.

 

[Deezul1]

Go with the 4K set, you can always watch the tach. I have the 4K and the stock valve springs and have not had a problem with valve float up to 3600 which is all I go to on purpose.

 

[Cummins Corvette]

Definitely the 4k... ... ... ... definitley.

 

[Jim Fulmer]

Thanks guys, the 4K update is on order.



Jim