High performance injectors with a mechanical IP?

[rlvelin]

I am in need of injector replacement (200,000+ miles on possibly stock injectors) and am considering high performance injectors. It seems that the most benefit from high performance injectors can be gained when used in conjunction with a DS4 pump, is this the case? Is it worth coupling high performance injectors to a mechanical IP? Does it require turning up the fuel at the pump or is it all controlled by injector nozzle size and pop pressure? Thanks for any input.

[cruzer]

I'm running Kennedy's injectors w/a new Kennedy stk 4911 mech pump. I did turn it up pump 1/8 turn b4 I installed it. According to my EGT's, I could turn it up some more, but b4 I do I will be installing a GM8 turbo, then see where EGT's are. EGT's will determine if more fuel or boost can be added.

The performance injectors atomize the fuel better.

All of my mods were done at the time except for the exhaust & gauges. I did have the Banks waste gate arm to increase boost,but I like the T/M better. I am extremely satisfied w/ all the mods. The power increase was awsome. Thanx TDP members.

The GM8 was given to me so I will see what it does in the near future.

[ 09-21-2004, 12:38 PM: Message edited by: cruzer ]

[rlvelin]

Cruzer
Will increasing the metered fuel with new stock injectors produce worthwhile power benefits or is the higher pop pressure required to atomize the increased amount of fuel? I see you turned up your pump before installation, would adjusting the fuel metering in small increments between test drives to make sure the EGT's are in check work or is there another method?

[cruzer]

There are people on this page that are more knowlegeble about this subject than me. That's for sure! All I can tell you is what my experiences are and some of the research I have found. I do know people who have turned up the pump w/stk injectors and got more power, and I was considering doing that b4 I cracked a piston from past overheating. I felt the 6.5 was very disappointing at that time. In my current configuration, it is a completely different truck. I thought it was max'd out. Boy, was I wrong!

The exhaust was a very good upgrade as you probrably know. W/the Banks kit they did describe turning up the pump, but you had to keep an eye on EGT's. The T/M instructions on tuning also require watching EGT's. For pulling a load, find the biggest hill so you can adjust boost to achieve max pulling power and keeping EGT's in check. Incremental adjustments, I think are required for boost and fuel, that's why I only turned the pump 1/8 turn in the beginning. Then I started tuning the T/M and stopped at 13-14psi sustained, I didn't want to go beyond that. The way it sits now, I feel I could turn up the pump a little more. I still have room according to the EGT's. I not going to do that until I see what effect the GM8 will have. I drive by the gauges when pulling.

Performace injectors atomize better giving you a more efficient burn, which is cooler and creates more power. Call John Kennedy or look thru past post for good info on this subject. GMCTD is a good source too.

FYI, Keep your cooling system serviced, and consider those upgrades too.

[lineman]

Revelin,I am currently running a turned up pump with stock injectors on a truck exactly like yours.I have 20k miles on the pump and injectors, 200k plus on the truck.I pull a 28 ft stock and flatbed trailer with it and it is my daily driver.I was amazed at the difference in the power.However I can't tell you if it felt so much better because of the pump being turned up or because it was so weak from wore out pump and injectors.All I know is that I am extreamly happy with it now.I will have my 4" exhaust and turbo master on,along with gauges shortly.This will help even more!And believe me,I would'nt trade this dependable truck off for anything.Even with 200k plus on it!......Lineman

[rlvelin]

Thanks for the insight guys. I think I will install stock injectors and play with the pump a bit as I have plenty of room with the EGTs thanks to the boost controller. The improvements should be significant enough that I will be thrilled even if I don't know what more could be gained with high pop injectors. The money saved on stock rather than high performance injectors can be put towards a new pump or possibly cooling mods although I haven't had cooling problems.