PWR SHFT

Will the stock PCM be able to control the motor past 7K? I know the tables only go up to 7K but I would like to turn the new motor to 7500. Can it do it and if so how?

PWR SHFT

Anyone?

dookie454

I have a log where I used a air cutter to spin an old distributor.. if I can find it I'll try to get it to you Im sure I went over 7000 a few times.

It probably wont tell you alot but maybe you can get something from it.

slomarao

7k ya it will be okay. 7500rpms, no way no how. Not exactly sure how and why the opti wont fire past 7k but it wont do it. Its been a common LT1 problem for a long time.

dookie454

I checked my datamaster logs, It shows RPM climbing to 6375rpm then it stops and flatlines until it drops below 6375rpm on every log... dont know if Datamaster 3.4.1 can read past 6375?

Some of the other parameters seem to climb at least a couple hundred rpm past that . Im not saying the PCM wont keep going to 7000 im saying My Datamaster 3.4.1 doesnt display it.

Injuneer

6,375 is the limit on the 8-bit field. 255 x 25rpm/bit = 6,375.

The Opti continues to put out a reliable signal at least to 8,000rpm... I have a data log to prove it.

hosspwr94

But your not using stock pcm though! Cheater!

PWR SHFT

OK. So from what I am hearing, If I want to spin the motor to 7500 RPM, I need an aftermarket computer. Can I get away with 7K to start so I don't have to incur the expense right away?

slomarao

yes you should be able to do it for a while.

Injuneer

Check around.... I'm pretty sure Rick Abare was running his stock PCM to 7,800rpm at one point.

PWR SHFT

Well for the added cost of an aftermarket PCM, I can build a 396 instead of a stock crank 355 and bring the RPM range inside the 7K limit of the stock PCM. I guess I will be adding a post about the Golen Shortblocks and what people think of them.

Thanks.

ramermanz28

Another thing to think about is the amount of force being applied to the rotor assembly. I overspun my OPTI and the rotor flew apart. Car stopped dead in its tracks. Towed it home, pulled the OPTI apart and there were little pieces of rotor all over the place. It knocked out the sensor and metal wheel as well. I was running a Delteq so I replaced the sensor and wheel and didn't put a rotor back in. Worked like a champ. So all I'm saying is that I don't think the design of the OPTI was meant to handle that kind of force. Just my experience, I could be wrong. Good luck, Rob.

Injuneer

Here's a post by someone running the Opti to 8,000rpm, but not without problems. Point is, he indicated he did this with a stock 92/93 PCM. The problem was the limited programming above 7,000rpm, and the Opti's tendency to disintegrate rotors.

https://www.camaroz28.com/forums/sho...08&postcount=7