RPM limits

[That GN Guy]

Now my GN is still under the knife getting revived, but I was wondering what some older members ( not by age) consider reasonable RPM limits are for various components. I know these are low rpm engines from the factory. I know max hp and torque are defined by heads/cam ect.

But from my searches there is no single thread regarding RPM limits. If someone was to build a solid roller motor, at what point would the main/cam/rod bearings fail? Rockers and springs? Ignition and PCM? Tranny problems?

A good friend of mine passed away recently who built a 9k RPM 95 Z28, a stark contrast to my 94 shifting at 6k. He was a motor head at heart and a good guy. Anyone here built a high revving 3.8? This is a conversation starter not a build thread, just wondering what kind of interesting builds have taken place in the TR world.

 

[Nick Micale]

......................But from my searches there is no single thread regarding RPM limits. If someone was to build a solid roller motor, at what point would the main/cam/rod bearings fail? Rockers and springs? Ignition and PCM? Tranny problems?..........

There are no threads regarding RPM limits because that is only a small part in building a complete performance car, especially a turbo car.

Our 50 year-old V-6 engine was designed for low-end torque and power, unlike the newer engines which need RPM with their multiple valve heads, as well as operating for fuel economy and emission requirements.

The first consideration of our turbo performance goals is how the car going to be driven and used, is it street or track or both, or what percentage of each?

It is extremely important that the build has compatible parts to provide the final combination to safely and reliably perform as the owner desires.

I can, and have built, a GN with a 9000+ RPM limit when needed, but at 5000 RPM on the street it can only be maintained there for a couple seconds or so, and still "kill" most performance cars on the street if it is set up properly.

My race car RPM limit is set at 8000 RPM, but would still make power above that limit, but I do not need or want it there to achieve my performance level which is below 7000 RPM.

I start with the performance level desired and use, then put together a build that is well below that level for reliability and being consistent, and the budget is usually a significant factor as well!

 

[bison]

There are 8000+ rpm v6 engines out there. Usually the Buick 90* engines commonly break valvetrain parts when rpm is pushed.


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[1986 Buick GX1]

I remember touring the Indinapolis Motor Speedway Museum in '88 and they had several engines on display.
The two I remember in particular were the Chevy Ilmor V8 putting out 750 HP at 9,000 rpm and the Buick 3.8L Turbo V6, de- stroked to 3.4L, pumping out 820 HP at an incredible 10,500 rpm, but then again as mentioned, unlimited funds.
Probably not a good street cruising combo. Lol