Does anyone know if the over speed assembly or rev limiter, can be removed without causing issues with the ignition system on a 500 Bulldog engine. It has a Thunderbolt IV ignition on the engine and the engines are in a 99 Fountain 42 Lightning. Thanks in advance if anyone has any information on this.
Al

It can be removed, but you'll need the wiring harness for a regular TB IV off a Merc black engine.

Thanks Griff, I think I will look at other options to update the whole ignition system.

I'm looking at the same thing- The newest style of the HP 500, the rev limiter is built into the ignition module, it's not a separate box. Is this also able to be bypassed? I'm referring to the set-up with the knock sensor. If not- is it possible to have this re programed for a higher limit.

You may want to look at the Daytona Sensors ignitions. Fully programmable custom timing maps in 2D, or 3D, as well as idle stablization feature, built in rev limit thats adjustable, and preloaded mercruiser timing maps, that can be changed by turning a dial. Compatable with the Mercury Thunderbolt distributor as well.

I have wrote some timing maps on quite a few of these boxes. Even though I drive a truck, have no hands on experience with engines whatsover, specialize in google searches and reading magazines, the results have been good with those ignitions. For the price, considering they come with a good coil, they are are a good deal in my opinion, and very versatile.

The 500 Bulldog is a great candidate for a camshaft upgrade, with some additional rpm.

Thanks Joe, that is the system that I am looking to use. I also have considered using a DUI disributor as an option. Anyone have any thoughts on them? My only issue with the Daytona box is just figuring it out since I am an older person who does not get along good with modern technology. : ) I know some younger people that can figure it out for me if I get stumped. I quit drag racing last year because the class we ran in just got to complicated with all the computers.

They are pretty basic , especially if you want to run a simple pre programmed timing map . Data logging, 3d maps, can get a little more high tech though.

You can basically install it, select from the preprogrammed maps by turning a dial, set the rev limiter by turning a dial, and go. The nice feature is being able to use idle stabilization, which at idle, will bump timing to help maintain a minimum idle rpm, which is nice around the docks.

That is the way I am going to go. I see Barowski has them so that will be my next step. I have already upgraded the cam and everything else on the top ends so this will finish off the build for this year. (Hopefully)

The Daytona is basically the Crane HI-6M that is no longer available. I used that on my last boat and it is a very simple system to set up, and very reliable. When you consider everything that is packed into that box it's a pretty good deal. Most likely that is what I'm going to be using, with my new motors. It's a lot easier to just buy the Daytona box, than trying to hunt down a pair of V8-HP modules and then buy a set of rev limiters. If you do go with that set up, don't forget to buy the matching rotor for your mercury distributor.

Will this ignition work with a distributor from a 96 502 MPI?