4age 20V rpm limit

[RXi20]

What max rpm can the the STD rods on the Blacktop handle?

I have forged pistons on std rods, with a set of mild cams 9mm lift, with toda valve springs.

Installing an aftermarket ecu this week, just wondering what the motor can safely rev to, with breaking.

[onnaj]

From what i remember most aftermarket ECU's for the Blacktop (like Blitz, JAM, TOM's, etc) rev to about 8500 rpm. So i consider that as a safe limiter. Stock is 7800 rpm for the 5-speed and 8250 or so for the 6-speed ecu. Without a catalytic convertor you can rev about 200 rpm more on a stock engine.

[RXi20]

Thanks buddy

[jdm86gtz]

From what i remember most aftermarket ECU's for the Blacktop (like Blitz, JAM, TOM's, etc) rev to about 8500 rpm. So i consider that as a safe limiter. Stock is 7800 rpm for the 5-speed and 8250 or so for the 6-speed ecu. Without a catalytic convertor you can rev about 200 rpm more on a stock engine.

I have a Mine's ecu with an 8400 rpm limiter.
The 5sp ecu also has an 8250 rpm limiter.
Going by posts on http://www.ae86drivingclub.com.au/ people have lost rods at around 8500 but no idea if oem rod bolts or ARP bolts were used.

[yoshimitsuspeed]

8500 is a good general limit because that's about what the stock oil pump is reported to handle semi reliably. Even then if you spend much time up there you will want to inspect the oil pump religiously. Rods are hard to quantify because people have broken the stronger 4AGE rods or even forged rods just at stock redline. It's just very rare and often caused by something else that is often overlooked. 8500 should be pretty safe.

[onnaj]

When I had the 5 speed ecu my rev limit was 7800 for sure. Maybe you have a 5 speed and no cat, then you can rev some more as stock

[death_blossom]

why does having no cat converter allow you to achieve a higher rev limit?

[yoshimitsuspeed]

why does having no cat converter allow you to achieve a higher rev limit?

Lol there is no reason a cat would have any effect on your rev limit.

[death_blossom]

why does having no cat converter allow you to achieve a higher rev limit?

Lol there is no reason a cat would have any effect on your rev limit.

I thought not, haha.

[onnaj]

I met 2 people that were able to rev higher after they removed their cat. So i'm not making this up to you guys. Don't know why this happens, but it does.

[yoshimitsuspeed]

I met 2 people that were able to rev higher after they removed their cat. So i'm not making this up to you guys. Don't know why this happens, but it does.

Option a. is that it was so clogged it actually stopped the motor from reving or option b. and IMO much more likely believing they did a performance mod and wanting to see results from that mod miscalibrated their butt dyno.