It should say on the module what the advance is. It should say V8-xx. The xx is the amount of advance. Or post the part #. I have a full list of all TB IV modules and advance amounts at each rpm.

well, its not a msd soft touch as stated. its wired right to the tb4 unit and just looks like a small rect box with some merc numbers on it

823755A1 and 2425

also the tb4 unit is stamped 5f23a v8-hp

so a 23* advance as you said...id like to know what the limiter is and how to bypass it if needed.

thanks Griff!!

kevin

NO!!! NO!!!! NO!!!!!!

A V8-HP module has 20* of total advance and all advance is in by 3000 rpms.

That rev limiter is factory merc and the same as whats on my 525SC. It will be at 5300-5350rpms. It can be removed. The ignition module and distributor are the same as all TB IV's. The rev limiter is just wired into them.

i was told this is a merc soft toch rev limitter, & dist. it worked perfect, i wanted to twist my mots to 6200rpm. i hope thier what i sad they are..

thanks larry! i hope so too, i think i can remove the limiter if needed. i just need to find out how the wiring would be done!

There is a Merc wiring harness that can be used in place of the rev limiter and it's wires. Can't recall what exactly what it is from. Just that my last boat, which was a '94 with the HP465 motor had the limiter module, and ignition module originaly, but the previous owner removed the limiter and installed a wire harness that was a direct bolt in replacement (no cut and splice thing) from a different ignition set up. Really slick and clean. Maybe this will shed some light and someone else will know exactly what I had.

Here it is



Item #43 is my factory limiter with wires.
http://www.mercruiserparts.com/Show_...2%2DF213244%29

Item #10 is what I had when the limiter was not used with my blower motor setup http://www.mercruiserparts.com/Show_...+ELBOW%29TB+IV