5.3L question

[RIPPEDK5]

What is the max RPM an L59 5.3L with a 4L60E can handle? basic mods are dual exhaust, hypertech max energy tuner, k&n intake, tayler wires..

I had a conflict with my rev limiter ( set at 5700 rpm) and 2nd gear full throttle downshift, which wanted to climb higher then the rev limiter

 

[boz42]

I don't know but the bottom end of those engines are impressive. I have heard of people taking them to 7000 without issue.

 

[4xcrazy]

I've had the one in the Avalanche up pretty at times, it seriously likes to do a hard downshift/passing gear shift, even when at freeway speeds, I never really noticed where it went in the rpm band, but it was up there around at least the 6000 range.

Kind of thinking that may have helped contribute to the failure of one of the lifters and a cam lobe, thinking maybe a lifter bounce/chatter or something, maybe need tighter springs for high rpm use.

 

[RIPPEDK5]

I had decided i wanted to open it up coming on to a highway. Put it to the floor and it shifted down to second and hit the rev limter at 5700 rpm, hesitated, then shifted to 3rda and i was off passed 120...

Justdonta want to damage the motor

 

[4xcrazy]

From what I'm bring told by the engine builder, if you want to run high rpms, you'll need to build up the top end primarily, he's telling me the bottom.ends are actually pretty well set up..

 

[Lifted87chevy]

4xcrazy is right. Everything ive read says the valse springs are the main problem when you want to raise the rpm's.

 

[454Sub]

That is correct, the LS and the all the other SB and BB Chebby motors have the same weak point, its the valvetrain. Both float valves at high RPMs, and that will lead to some nastiness down the road. I would toss a cam with some LS6 valvesprings in that 5.3 and that thing will be real deal.

 

[supermotard750]

i spun a stock bottom end to 7400 with texas speed 5.3 heads infront of my 4l60 in my camaro at least twice a week for a year. i pulled the motor apart at 140k miles and still had cross hatch in the bore and the bearing wear was minimal and even

 

[RIPPEDK5]

Good to hear i wont hurt it

But do i turn the shift point down or the rev limiter up? (shift point is set 300 rpm above stock and rev limiter is set at 5700)

If money ever allowed, i would get new heads, cam and valvtrain

 

[supermotard750]

The shift points get set to what ever you want with a stock converter 300 over is fine. But I always make sure my limiter is set 3-400 higher then the highest shift point

 

[eagle mark]

There's several tables for shift points, normal, cruise, hot, cold and performance. None will work correctly if you have a gear and tire change. That needs to be corrected first. 400 to 600 changes needed.... luckily software does them all one shot. Start messing with one and you can have many issues.

If these are set correctly the downshift will not happen if motor will over rev.

 

[y5mgisi]

From what i have read on that subject, a stock 5.3 will do 6700 without any issues. But, as others have said, the top end is the "weak link" for rpm. But stock shouldn't have problem with 6700.

 

[jake 03]

You really dont have worry about over revving an ls bottom end but you can start bending pushrods over 6500 if the topend is stock. For what its worth the 5.3 in my 03 silverado saw 6400 pretty regularly with no ill affects.