Safe RPM Limits

[notaustin]

Soo, with this next stimulus check looking like it might be significant (no guarantees of course, and not starting a political debate), I'm looking at going and getting a big turbo, and moving the PowerBar up. So, what is a safe RPM limit for the factory valve springs, or are they already pretty maxed out? And if anyone has experience with the RPM limit on the Mountune upgraded valve springs, that information would be good to have as well

 

[notaustin]

I've heard as high as 7200 on the factory springs but I want to confirm that with someone who has potentially tried it

 

[TyphoonFiST]

10k*

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[the duke]

7500rpm or so.

 

[briandee]

I think I heard the house rejected the $2,000 payment, so we may be stuck with $600 in upgrades!

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[TyphoonFiST]

I think I heard the house rejected the $2,000 payment, so we may be stuck with $600 in upgrades!

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Countered it with a 2k stimulus with getting Rid of Section 230 against big Tech*

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[Ecmdrw5]

Countered it with a 2k stimulus with getting Rid of Section 230 against big Tech*

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[notaustin]

sooo, about the rpm limits lol

 

[notaustin]

7500rpm or so.

Is that the mountune springs?

 

[the duke]

Is that the mountune springs?

Stock hardware of the valve train. Test it and see.

 

[haste]

I've read but can't confirm that the hard coded RPM limit on these engines is 8300. The engine isn't designed for high rpm but seems to handle it OK.

I personally limited my RPM to 6900 with my x37 because any higher won't take advantage of the turbo. I've had the 6900 limit for over 50K miles now with the x37 and use the limiter more than I should.

My buddy has a whoosh hybrid and runs 7k RPM limit without any issue.

 

[Rocketst]

I drove with the rpm at 8k for almost a year with a forged engine.

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[Sam4]

They say anything's a dildo if your brave enough, so in the ST's case - your right foot will know the max RPM's. It sure isn't 6500, it'll flog pretty well but runs out of air up there pretty quick.

 

[Rocketst]

Also, keep in mind that rpm kills things boost doesn't. So if your planning on running anything past 7k, that you have a built engine, the turbo can still pump more air, and that your power curve will benefit before trying to up it. I'm running a g25-660, I have plenty of headroom and am running a built polished and ported head with aftermarket cams and a forged bottom end with an oil baffle system to improve oil flow. I have a lot of engine work to get to 8k safely. It's not for the faint of heart.

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[M-Sport fan]

I would even consider a dry sump system if I were ever thinking about regularly screaming it that high.

 

[EnthusiaST]

I'm at 7k with no issues besides a maxed fuel system. Upgrade your fuel system!