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rssteiny 02-20-2010 07:22 AM

msd rev control ?
 
I am curently running the msd6 blue box with my stock 500hp distributors, if i get msd rev control boxes that plug into my msd6 boxes can i still use my stock distrs and if so will ineed to rewire the system as i do not want the stock rev limiters to work.

thanks

Boat1 02-20-2010 10:10 AM

What year is your engine. Assuming it is a carbureted HP500 it likely has a MEFI 3 computer that actually controls the rev limit function. Your MSD box is simply aplifying the spark to the plugs. To raise the rev limit you likely will have to have the computer setting changed. This still will be cheaper than the soft touch control from MSD. To lower the existing limit the MSD could be used.

rssteiny 02-20-2010 02:14 PM


Originally Posted by Boat1 (Post 3050959)
What year is your engine. Assuming it is a carbureted HP500 it likely has a MEFI 3 computer that actually controls the rev limit function. Your MSD box is simply aplifying the spark to the plugs. To raise the rev limit you likely will have to have the computer setting changed. This still will be cheaper than the soft touch control from MSD. To lower the existing limit the MSD could be used.

How do i get the computer changed and yes i am 2000 carb 500hps.

Boat1 02-20-2010 04:37 PM

A few suggestions, both are outstanding. Young Performance, Eddie Young, 615-216-7449 or Precision Marine, Mark Boos, 504-469-7463. They can better explain the process.

Young Performance 02-20-2010 11:01 PM

If it is a hp500 carb engine, then it doesn't have an ecm (mefi). The rpms will be regulated be the ignition module. Yes, you are correct that if you add a soft touch rev limiter the Merc. module will still control rpm limit. Whenever I add an MSD box, I have an aftermarket distributor as well. I would use the MSD ready to run so if the box ever fails, you can still run the engine without the box. That dist. does not require the use of a box.
Eddie

Boat1 02-21-2010 09:44 AM

My bad, I sure thought there was a MEFI computer controlling timing with spark knock feature. I guess it was 500 EFI when they switched. Sorry for the mis-information, thanks Eddie.

rssteiny 02-21-2010 03:03 PM


Originally Posted by Young Performance (Post 3051381)
If it is a hp500 carb engine, then it doesn't have an ecm (mefi). The rpms will be regulated be the ignition module. Yes, you are correct that if you add a soft touch rev limiter the Merc. module will still control rpm limit. Whenever I add an MSD box, I have an aftermarket distributor as well. I would use the MSD ready to run so if the box ever fails, you can still run the engine without the box. That dist. does not require the use of a box.
Eddie

So if i run that dist, with my box and a rev control box then the rev control will be regulated only through the rev box correct.

Young Performance 02-22-2010 12:53 AM


Originally Posted by rssteiny (Post 3051678)
So if i run that dist, with my box and a rev control box then the rev control will be regulated only through the rev box correct.


With the MSD ready to run (or any Pro Billet dist.) dist., that is correct. The rpms will be controlled by the rev limiter.
Eddie


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