anyone here build a high rpm 4.8 ls,naturally aspirated?
just curious if any have bothered to do this,if so what were your results?
High hp/rpm 4.8 NA ls build
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rustbucket79
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Re: High hp/rpm 4.8 NA ls build
Sally most likely pointsbout that LS= SBF.
High rpm smallblocks hve veen in the game for some time. I think it wa Pro Stock where they destroked & built the smallblocks around 280 cui and 11.000 rpm. Unfortunately my knowledge of this part of history is weak.
What do you consider high rpm? For some that’s 6000- for othera 13.000.
There are some certain ‘rules’ of what to do while rpm goes up, and they hacen’t chnged lately as far as i know. Sometimes there’ some new tech like materials that makes life easier. Like when titan valves were infroduced.
You could read up on NASCAR- engines. Lot’s to be learned there.
High rpm smallblocks hve veen in the game for some time. I think it wa Pro Stock where they destroked & built the smallblocks around 280 cui and 11.000 rpm. Unfortunately my knowledge of this part of history is weak.
What do you consider high rpm? For some that’s 6000- for othera 13.000.
There are some certain ‘rules’ of what to do while rpm goes up, and they hacen’t chnged lately as far as i know. Sometimes there’ some new tech like materials that makes life easier. Like when titan valves were infroduced.
You could read up on NASCAR- engines. Lot’s to be learned there.
How to turn GURU in an instant.....
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jeff swisher
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Re: High hp/rpm 4.8 NA ls build
The LS engines will REV I will give them that.
Here is a bit of what I learned doing a 6.0 LQ9
It was carbed and liked the 800 CFM better than a 750.
Did not try anything larger.
The stock lifter trays were replaced with New ones and holes drilled for oil drain back Rocker trunion upgrade to bushings and Morel Lifters.
Took the stock LQ9 cam and reground it to a 222- 232 @ .050 on a 109LSA .557" lift, Pac 313 Rate Beehive springs 130 on the seat.
Now the ERROR in that deal was not enough valve spring for the RPM this 6.0 wanted to rev to.
I ported the LQ9 heads and added some more angles on the exhaust valve job vs the stock one.
Buddy stuck it into a long bed truck and was shifting for months at 7000 RPM.
No issues.
The day the not enough valve spring came up was the day he was not right in the head and forgot to shift and the thing went past 7600 rpm.
Lifter Loft done it in.. the lifter crashed down on the closing side and then there is the miss that was hard to find until we took the poor thing apart.
That is not much cam and it is an old GM HOT LT4 cam master for the older roller engines not the LS.
Go bigger on duration and keep the valvtrain stable and you should not have any issues revving the little 4.8 LS.
You need a cam that is stable up there and I do not think I would use lifter i bucket deals.
I think I would go link bar.
I like more carbs than 1 also so think tunnel-ram.
Here is a bit of what I learned doing a 6.0 LQ9
It was carbed and liked the 800 CFM better than a 750.
Did not try anything larger.
The stock lifter trays were replaced with New ones and holes drilled for oil drain back Rocker trunion upgrade to bushings and Morel Lifters.
Took the stock LQ9 cam and reground it to a 222- 232 @ .050 on a 109LSA .557" lift, Pac 313 Rate Beehive springs 130 on the seat.
Now the ERROR in that deal was not enough valve spring for the RPM this 6.0 wanted to rev to.
I ported the LQ9 heads and added some more angles on the exhaust valve job vs the stock one.
Buddy stuck it into a long bed truck and was shifting for months at 7000 RPM.
No issues.
The day the not enough valve spring came up was the day he was not right in the head and forgot to shift and the thing went past 7600 rpm.
Lifter Loft done it in.. the lifter crashed down on the closing side and then there is the miss that was hard to find until we took the poor thing apart.
That is not much cam and it is an old GM HOT LT4 cam master for the older roller engines not the LS.
Go bigger on duration and keep the valvtrain stable and you should not have any issues revving the little 4.8 LS.
You need a cam that is stable up there and I do not think I would use lifter i bucket deals.
I think I would go link bar.
I like more carbs than 1 also so think tunnel-ram.
Re: High hp/rpm 4.8 NA ls build
Sorry......missed the two little ls letters!
I was sorta poking fun at such a tiny post with NEAR zero info about what OP was running.
Guess it was just me
6sally6