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Max Rpm's Lq4

s10473

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s10473 Enthusiast

s10473

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I have a LQ4 6.0. I am looking to see if anyone has raised their max rpm's. I am doing an EFI custom tune with a supercharger so looking to get a little more spin out of the blower. What is the highest and safest mas rpm.

Ranger Senior Enthusiast

Ranger

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My 6.0 usually shifted at 5k but I think just under 6k is the max for short periods.

Schmids5.3l Senior Enthusiast

Schmids5.3l

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I have a LQ4 6.0. I am looking to see if anyone has raised their max rpm's. I am doing an EFI custom tune with a supercharger so looking to get a little more spin out of the blower. What is the highest and safest mas rpm.

 

5,700-6,000 on factory valve train, after that you'd just be making noise and not power.

 

In the past you mentioned you were wanting to run max psi safely(10~)..are you? Messed with the timing any? An extra few PSI will really be felt, as well as reving past the factory preset RPM red line of 5200 or whatever it is.

 

Edit: your sig says 6lbs, I think you could swap pulleys and run 8psi pretty safely. That would be a noticeable increase. I'd keep a lot of the factory torque management with your tuning though, with 6" lift and bigger tires + a blower the 4l60 would probably feel better. :(

svensk Senior Enthusiast

svensk

Posted
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I have a LQ4 6.0. I am looking to see if anyone has raised their max rpm's. I am doing an EFI custom tune with a supercharger so looking to get a little more spin out of the blower. What is the highest and safest mas rpm.

I'd keep a lot of the factory torque management with your tuning though, with 6" lift and bigger tires + a blower the 4l60 would probably feel better. :(

 

I think he's got a 4l80 or 85e. Even with that junk I would still beef it up a bit, maybe transgo and stall it.

Schmids5.3l Senior Enthusiast

Schmids5.3l

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I think he's got a 4l80 or 85e. Even with that junk I would still beef it up a bit, maybe transgo and stall it.

 

I didn't even notice that it was a 2500 :( With the 80e your in better shape!

s10473 Enthusiast

s10473

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Thanks Nytemare.

Last week I installed 44lb injectors and did a Efilive tune. I was running out of stock injector at 5200 RPM. I only have 6lb of boost now but have a new impeller coming in that will up my boost by 2 to 3lbs. So I will be on the dyno then while tuning. I was just seeing how high I could get the rpm's up to. Not going to raise the limit if there is not a noticable gain.

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