How do you...

[Strider Negro]

how do you raise the rev limit on the motor without actually killing it
sure there are ecu upgrades but let's assume for example i have a car that redlines at 6000 rpms
how would i safely be able to bring it to 9 or 10 thousand rpms without killing the motor????

but that is if it's possible...(just wondering..)

[Doug000]

Originally Posted by Strider Negro

how do you raise the rev limit on the motor without actually killing it
sure there are ecu upgrades but let's assume for example i have a car that redlines at 6000 rpms
how would i safely be able to bring it to 9 or 10 thousand rpms without killing the motor????

but that is if it's possible...(just wondering..)

The redline is not just an arbitrary number. It is actually based on how the engine is built.....bore, stroke, compression, tolerances, balance on the recipricating mass. Depending on your engine you may not ever be able to safely do 9000+ rpms. But with a factory redline of 6000, you could spend about $3,000 having your engine rebuild and balanced and you could probably get 7500 rpms successfully. Of course, this number is just guess since I don't know what kind of motor you have.

[BeEfCaKe]

Drop a s2k motor in...

[v10_viper]

Originally Posted by BeEfCaKe

Drop a s2k motor in...

And have no torque?? You can get a higher redline out of an engine with stronger and lighter parts, but it's gonna cost you.

[SaabJohan]

The stress on the engine internal increase at the square of the rpm. Increase the rpm from 6000 rpm to 10000 rpm and you have increased the stress about 180%.

Not only should the engine be able to resist the rpm it should also deliver power. The main focus on making a high speed engine should be something like this:

Light piston/conrod assembly, most important is piston weight.
A stronger piston/conrod assembly.
Short stroke with large bore and a long conrod.
A valvetrain with harder springs and lighter moving parts. Larger valves and mechanical lifters, better valveseats.
A camshaft with more duration and higher lift.
Friction reduction with nikasil, diamond like carbon and so on.

That the engine doesn't get much torque isn't that important since it will deliver the power anyway. It's just like riding a bike in diffrent gears, pull hard and slow or fast and easy; it doesn't matter which one you choose because you will get the same performance anyway.

[454Casull]

Two cars with the same body shape and HP have the potential to reach the same top speed, regardless of torque. Acceleration at any given RPM also depends on the HP (the transmission can give the same torque@RPM if HP is the same).

Did that make sense?

[v10_viper]

Originally Posted by SaabJohan

The stress on the engine internal increase at the square of the rpm. Increase the rpm from 6000 rpm to 10000 rpm and you have increased the stress about 180%.

Not only should the engine be able to resist the rpm it should also deliver power. The main focus on making a high speed engine should be something like this:

Light piston/conrod assembly, most important is piston weight.
A stronger piston/conrod assembly.
Short stroke with large bore and a long conrod.
A valvetrain with harder springs and lighter moving parts. Larger valves and mechanical lifters, better valveseats.
A camshaft with more duration and higher lift.
Friction reduction with nikasil, diamond like carbon and so on.

That the engine doesn't get much torque isn't that important since it will deliver the power anyway. It's just like riding a bike in diffrent gears, pull hard and slow or fast and easy; it doesn't matter which one you choose because you will get the same performance anyway.

I know an engine that redlines at 8200 RPM and has a 5" stroke, so you dont always have to have a short stroke but it helps reduce the stress, but it depends on the reliability you want from that engine, however I dont know the reliability of this engine. Basically you just need reduced friction, but it's hard to get that.