I searched the net and can't find any info on setting timing on a Cummins C8.3 turbo 300hp in a motorhome. The CPL is 1406.

Does anyone have the stock timing number, and any info on how to check and advance the timing? I have a number 10 fuel plate in it, and am considering trying advancing the timing a bit.

Edit - engine is a 1994 mechanical.

Thanks for any help,

 

Can you use the same P-pump timing tools as for a 5.9 Cummins???

 

I think so. We have the same pump and use the same fuel plates.

 

I'd start there then... The tools aren't cheap, but they would be good to have anyway...

 

I was searching on "Cummins 8.3 timing" and finding nothing. I just searched on "Cummins injector pump timing", and "injector pump timing" and finally found some info.

I need to look at my data tag tomorrow and see if it says the current timing setting with the CPL of 1406. Two guys with the 8.3 in motorhomes that installed the banks kits reported good results from advancing 4 degrees. I want to be moderate not agressive in what I do, so any info will help.

This link and the links off of it answered some of my questions:
https://www.dieselbombers.com/12-val...ming-help.html

 

When i got my ppump in off of an 8.3 cummins it was set for 15 degree timing. but it was off an 00 dump truck. and they aren't the exact same pump but they are close except for the oil returns. also found that out for my pickup. idk if that helped at all but i woulda liked for somebody to tell me it was at 15 degrees before i tried advancing mine.

 

It'll be 13,15, or 17(typical Med Duty timing). Just dont go too far past 19, because it starts getting risky on the headgasket. Sure makes the power better at the top end though.

 

ya mine ran good once i figured out the timing but mines at 16.5 now for my pickup. it has alot better top end too. but also the 4k gov springs help that 2

 

If you still have questions, try PM'ing JGK, he's local timing guru for these pumps up in the Idaho area.

 

I just found the data tag. CPL 1406, 12 degrees is stock. We pull a LOT of weight.

We did a early retirement and live fulltime in our Bluebird Motorhome. 33,000 lbs with full fuel, propane, fresh water, and all our "stuff", towing around 3600 lbs for the tow car. All up we're almost 37,000 lbs pulling the mountain grades.

The only mods so far are a number 10 fuel plate, and a Aero 4040XL muffler.

I am considering trying 15 or 16 degrees at some point in the future. First I want to install a boost and EGT gauge (on order next week) and pull some long mountain grades as she sits now, before altering the timing.

With the weight at almost 37,000 lbs, number 10 fuel plate, stock timing 12 degrees- what do you guys think final timing should be? No black smoke at all now - pretty clean and clear. I haven't messed with the star wheel at all yet - factory setting on it.

94 mechanical C8.3 turbo 300 hp. Here's the current rear wheel dyno numbers: https://www.dieselbombers.com/member...mins-c8-3.html