Does anybody know how to remove rev limiter
 

Does anybody know how to or know of somebody that knows how to disable the built in rev limiting ability of the Thunderbolt Five ignition system. It is factory set at 5050 rpm. I need to get my motor spinning to 5400. I have the power to do so.I already know that I can replace ignition system with MSD etc. to achieve this but I want to retain knock sensor feature that this sytem has.
Thanks in advance for any info.

Dave:confused:

P.S. This is a 454 Magnum carbed engine with a Whipplecharger.It has a stock bottom end with modified cyl heads. It does not have an ECM. The module in question is bolted to the side of the dist. I have an idea about putting a resistor in the line somewhere to fool it. I was just wondering if anyone out there has done this.

You will have to send in the ECM to have it reprogrammed. If you've added a lot more power, you should do this anyway. If you haven't done any major internal mods, then you shouldn't spin it much faster anyway.

This may be a dumb question but have you asked Dustin? Seems to me he must have to deal with this on a regular basis. ECM programming is part of installation on the fuel injected engines. If there is some simple way to do this he should know and be willing to help you out.

Talk to Jim at Arizonia Speed and marine, They reprogram ECU's all the time. They are in Chandler Arizonia, their add is always in Power Boat , or Hot Boat, also in Poker Run Mag.

The way I understand what bigwavz is talking about is that he has an ignition module attached to the side of his distributor, not an e.c.u. As he stated the motor has a carb., not injection. I am not 100% sure on this, but I am almost certain that you can not change the rev limiter in this type of ignition module. I would have to say the best way around this is to get an aftermarket distributor.

I don't think there is any way to disable the rev limiter. You can replace the module with a TB IV module but you also lose the knock sensor. You can add an aftermarket rev limiter, but that doesn't help with the knock sensor problem.

Bob

not sure if this would work the same way or not but back in my jetskiing days we would be able to get rid of the rev limiters on those sealed units by drilling out a certain spot on the module....I think it would work the same in this application just need to find someone who knows what they are doing with those! :)

Dave
I have been looking for an economical solution for this broblem also. Arizona Speed wants big bucks to reprogram these modules. So if you find a solution please post it. My limiter cuts in at 4600 so I would be interested in buying your module if you dont need it for your fix.

gene,
Tell me what engine setup you currently have and any other details I might need to know.

Dave

Dave, I started with the basic 96 Mercruser gen V 300 hp 7.4L. I've gone to 9.6 to 1 pistons, an 850 holley double pumper, performer rpm intake, merlin oval port heads and a 224/230 roller cam. I'm obviously making some good hp above 4600 rpm but like you I can't get to it. I don't want to spin much past 5000 rpm so your module would do the trick for me. I bought a V6 module on ebay but it arrived D.O.A.
Gene

Hey guys, is it possible to wire in an MSD module in there inplace of the stock one? It seams like it should work, just may need a bit of detecive work to get it done correctly. Maybe a call to MSD may shed some light! :D

I think I'm on the trail of something. I spoke with Marc from BAM marine and he is looking into piggybacking a MSD box into the system somehow. I'll know more in a couple weeks.

Gene,
If I go with the MSD setup I will let you know and maybe I can sell you my old module or at least help you get to 5000 rpm.

Thanks guys!!!

I am battling with a similar situation on a pair of 454 Mags (carbed). My problem is one of the engines has the right module which limits the RPM to about 5350 and the other seem to have the module for a 330hp motor and the limiter kicks in at 4950.

The two solutions that I have identified are:
a) replace the module for the 330hp with the correct one or
b) replace both modules with the Crane Cams HI6M ignition modules which have adjustable rev limiters.
I like option "b" so if anyone wants to buy these modules let drop me an email.

Ian T.

I have a pair of 96/97 454Magnum Bravo's (carbureted) with Thunderbolt V ignitions in a 89 Formula 272/SR1.

As I understand it the Thunderbolt IV didn't have a rev limiter.

[COLOR=blue]CayFomula:
Email me at [email protected] and let me know how much you like to sell the 5350 module for.

Dave

I have a 96 500HP with the Thunderbolt IV and there is a plug that you can buy that replaces the initial plug and does away with the rev limiter.