I've got a question for you guys. I've got a pair of Merc 420's that I rebuilt last year and installed a set of roller Reed cams I picked up from Mild Thunder. The Cam specs were 232/237. After talking with Bob at Marine Kenitics we used 1.7/1.8 rockers on it which Bob said would change the duration slightly to 232/241. So with that said, last year I used the V8-24 modules the curve was steeper than I wanted so I bought a set of V6-14 modules. I always thought they were a 14 degree advance but I was reading tonight that on a V-8 they are only 6-10 degrees advance. Should I find a set of V8-20 modules or am I going to be fine with the V6's? My biggest worry is starting the engines with an initial advance around 24-28 degrees!

what are you running for total timing,im thinking around 34,so 34 - 14 = 20.that is where your initial timing would be set at.also,i run 34 locked on my cat and absolutely no trouble starting,they turn over very fast and fire right up.

Mike- from what I've read it would not be 20 because the module is not designed for a V-8 so the resistance is off resulting in a 6-10 degree advance. The only way I know this is because I just read 4-5 separate post saying that all others were getting and why? I don't know why this would be, as my Crane boxes don't have 4,6,8 cylinder selector. If you're running 34 locked I should be fine. I just want to make sure what I have will work, if not I want to start shopping before spring gets here.

Mike, (endeavor32 Mike lol), lots of us running locked out timing, no starting issues. I'd verify full advance timing and set it to what you need at full advance, and let the base fall wherever it may. Reason the v6 modules starting being used is for more timing at idle, to help with idle quality with bigger cams and what not.

We used the V-6 modules back in the very late 80s and thru the mid 90s on our blower motors as the timing comes in much sooner, better Idle and acceleration thur the mid range, less heat build up also. Back to your question of start up cranking, I never had a problem with the advanced timing when starting no hard spots or kick backs you will be fine in that respect. might be hard to find at a good price. a lot of us "old timers" still use them over those "fancy blue MSD thingies" lol

Mike, Joe, Abones,
Thanks for the reply's. Sounds like I'm not going to have an issue so I'm going to use them. I really wish I could use the crane boxes I have but none of them seem to be working. I'm going to check them out this spring again but if I get the same results as last year I'm going to use the V6-14 modules that I have.

The V6-14 modules give about 10* of advance on a V8 engine and all the advance will be in by about 2500rpms. You should be fine running them. Just set total timing to 32-34* and let base timing fall where ever.

Thanks Griff- thats what I'm going to do!

I run the v6 modules and only pay attention to the full advance timing as MT suggests. I believe I get 11-12 initial and run 30* all in. I have no issues starting with the v-6 modules.

my merc 454-420 rebuild to 485 hp were a pain at idle when engaging. my engine builder switched to V6 module... a dream come true! end of trouble! should have done that the first year, not the fifth year when I sold the boat!!!