Engine/Transmission (1994 - 1998) Fuel pump timing set too high!?

[Jerred]

With interest in advancing my pump timing to 15. 5 or 16degBTDC, I researched the procedure, obtained the parts/tools, got up the guts, and went for it.



I decided to first see where it was set at before adjusting. Using a dial indicator, I found that the plunger dept at TDC to be 5. 57mm. I have a '96 with the 180hp fuel pump (CPL 2174). According to every chart that I've seen, 14deg on a CPL 2174 is 4. 5mm. I had the valves set and fuel pump tuned by a Dodge dealer when I first bought the truck, 60,000 miles ago. The mechanic said he set the pump at 5. 25mm which, HE SAID, was SLIGHTLY advanced from stock. WELL, after verifying the plunger depth to be 5. 57mm, it appears that it is timed to about 19degBTDC.



It seems that the mechanic was reading the settings for the '96 truck with a MANUAL TRANSMISSION (CPL 2175), which many of you know has a 215hp fuel pump (my profile says manual transmission, but that's because I swapped them at about 150,000 miles, the truck still has the stock 180hp pump). 5. 25mm, where he set the pump at, sits at about 14-14. 5deg on the chart for CPL 2175 but if you extrapolate the setting out for the CPL 2174 (mine), 5. 25 is 17. 5-18deg (not sure why it was even higher than that when I checked it today).



Here's the question: since I've apparently, unknowingly, been running around at about 19deg on the pump timing (about 30,000miles stock and 30,000 miles with about 150hp increase from stock), what, if any, damage have I possibly done? Every since I added the extra hp, I've also noticed that the engine runs rough at high rpm/throttle/boost (2500rpm+/20-30lbs boost). Could this be a symptom of too high advance? I have a Banks fuel plate slid forward and what amounts to a 30lb wastegate and an extremely efficient intake and exhaust system.



Anyone have any thoughts? (besides me recalibrating that mechanic)

 

[bmoeller]

One thing having that much timing, from what I've read, is that it can possibly hurt the headgasket.



I've also read that using the pin to find TDC can be a problem. Apparently some are not quite in the right spot. Maybe that happened or the dial indicator might have been a little off.

 

[HoleshotHolset]

It's common practice for some people to adjust timing without using a dial indicator... . I wouldn't be surprised if he loosened the pump nut... cranked her over a little bit and tightened it back up.



I wouldn't worry about your headgasket until it fails... or exhibits signs of leakage. 19° of timing isn't all that much in the grand scheme of things.



Matt

 

[sewman]

If your timing is @ 19* it should run better @ higher rpm. I think @ 2500 your hitting the perset govenor speed & the fuel is backing off.

I don't think @ 30lbs boost you'll be hurting anything other than your bearings if you lug it much.

Bob

 

[wsmalley]

Your truck is fine. You have no worries nor should you have damaged anything. I ran mine at 20* for a loooooooooooong time before O-ringing and going higher. Plus you don't have enough fuel to worry about it. As far as the rough running, I would think it's a combination of the high timing trying to rev the engine higher with the governer saying NO. Solution: adjust your governer springs or get a 3k or 4k GSK and be done with it.

 

[Jerred]

Thanks so much for the replies. I think I'll turn it down a bit though. Thinking around 15deg. Anyone have any thoughts? I know it's really dependent on how much smoke I want.



It's funny that I'm a payday away from buying the 4000rpm kit from PDR!! Besides that, does anyone know which numbered fuel plate cooresponds with the Banks PP plate? I'd like to try a more aggressive one with the GSK.



Thanks again to all of you guys. I feel much better, and more importantly, I'm ready to keep diggin for hp!!

 

[HoleshotHolset]

If it were my truck, I'd set it at 16. 5° or 17°... that's the sweet spot for the 370 injectors that you're bound to install next.

I bumped the timing on Dad's truck to 15. 5° and it's not quite enough for the 370's. He's gonna raise it to 16. 5° when he gets around-tuit.



BTW, Piers has 370's on sale.



Matt

 

[SEmerson]

15 is too low

I would go 16 at the lowest

 

[Jerred]

In response to holeshotholset, yes, 370's are in my crystal ball.



I've been told though that with my stock 12cm exh turbo, I won't generate the kind of airflow that will do those monster injectors justice. Thoughts?



I've also heard something about the delivery valves in conjuction with the injectors. Any thoughts on those?



Again, thanks for all the help, you guys have been great.

 

[HoleshotHolset]

Jarred: The only way to see the real benefits of the 370's without having insane EGT's is to install a turbo that has more flow on the cold side.



You can control EGT's with your right foot and your plate to a certain point... . but after that you'll need a bigger turbo.



Installing a bigger turbine (hot side) will only delay the amount of time it takes to reach maximum EGT. You need to flow more (cool) air into the engine to fully burn the extra fuel from the 370's and realize the advantage they give you.



Anything past 35psi on the HX-35 is not a good idea because you're just blowing hot air past that point. Upgrading to a B1 hybrid turbo will flow plenty of air for the 370's and you'll have a HUGE margin of 'safe-zone', as far as EGT's are concerned, over the HX-35.



Some trucks require bigger delivery valves to eliminate a rough running condition that the 370's may exhibit... . some trucks don't need them. You'll get a lot more power with cut DV's, and the smoke will be out of control.



Matt

 

[RT66DOC]

Ditto what those guys said.

Mark at Piers told me 16 - 16. 5 with 370s.

 

[Jerred]

yeah, that's what I've been hearing as far as advance, with the injectors. I think that's where I'll set if (16. 5+-) and look around for good deals on turbos before dropping the coin on the injectors. I am trying to make a concerted effort to do things in increments as I am starting to realize (what most of you already know) that every engine is a little different and every new cookie needs to be evaluated separately, or the bill gets out of control.



SO, where I'll go from here is, 4000rpmGSK with HD intake springs and reset the timing to 16. 5.



After that, if anyone has killer deal on a big-ass turbo, you know where to find me!!



my wife is going to kill me...