Need IP lines, also IP questions

[Sparky_NY]

I recently (2 weeks) got a gruman step van with a 6.2 (88-J Code) The milage is around 130K and it runs real good EXCEPT has very poor low end torque. On slight grades it barely moves from a stop and generally crawls from 0 to 10mph but then seems decent as the rpm's come up. I do get black smoke under high load conditions and replaced the fuel and air filter which helped slightly. I am thinking its pump and injector time due to the mileage and they are slightly weak.

Any suggestions? Also the injector lines are quite rusty (not leaking) and I am afraid some will break when I try to remove the injectors. Does anyone have a set of pretty good lines available or a source to get them?

:(

[britannic]

If you have the original pump and injectors, then you should get a performance increase with new/rebuilt injectors and pump.

With the mileage, you might want to check the timing chain wear and maybe consider fitting a gear drive.

Consider upgrading the exhaust system and air intake (see Dr. Lee's mods) to take advantage of the extra fuel.

Avant Salvage can usually supply the injector lines, they advertise on the DP.

[Sparky_NY]

I located a set of injector lines right after making the post from Tim Wagner. The exhaust was replaced not long ago with a dual system with what appears to be pretty good size mufflers. After reading up on the forum and noticing the big restrictions in the intake I made a new snorkel for the air cleaner and riveted it on adapting it to 4" aluminum flex hose which I ran to the original location next to the radiator. I think the intake mod added some power, but nothing radical, although it sounds a lot more fierce. In the process I noticed the injector pump is advanced about 1/8 inch which was going to be my next test, there is no excessive diesel rattle (except for the first couple mins when the cold advance is working) so I may try a little more advance.

Should I stick with the stock injector/pump types or would different models be a advantage?

[smokin6.2]

A stock pump "turned up" with a pyrometer should help you experiment with what works best. Is this an old postal van??

[Sparky_NY]

No, its not a old postal van, it was originally purchased by a company that delivered bottled water. It is a 88 with the J code engine.

I am going to replace the injectors and pump just as a routine maint. because of the 130K milage. I have talked with Tim Wagner and if I am not wrong he does the pumps with the pressure increased slightly already when he does a rebuild.

[Animal]

Sparky,

This may help you out.

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&category=33555&item=2425425478

[britannic]

Tim rebuilt my pump to the 4911 spec. He told me that the injectors actually set the pump's pressure, so I replaced my stock inj.s with 6.5LTD which have a higher pop pressure. The set up works great with my wastegated turbo.

[Sparky_NY]

Britannic, I have seen mention of using higher capacity injectors, thats what I was wondering if I would benefit from. Yours is turbo'ed though which would need more fuel than a NA engine. I wonder if there is any reason to use other than stock injectors in a otherwise stock engine.

[britannic]

Unless you have a 300HP engine that can burn the extra fuel, you won't get any benefit from high flow injectors, only a big hole in your paycheck :D .

However, 6.5LTD injectors with their higher pop pressure can inject the fuel faster with better atomization for a cleaner more powerful burn. This reduces afterburning in the exhaust manifold if you increase the injector duration and helps keep the heat down (providing the pump isn't overfueling and there's plenty of air to burn it all).

[90LX]

I keep looking at Britannic's setup/results and keep wondering if it would help my truck. I now have the pump advanced about 1/8" and my EGT dropped 150F. Now it only goes to 1000F at 70 mph on flat ground with no trailer in 90+ Florida heat and A/C off. Boost maxes at 8 lb. Within 5 miles the coolant goes from 190 to 230 and keeps rising till I back off to 60 mph. I'll never get this truck to pull my 9000lb gooseneck. :( The pump was retarded 1/16" by previous owner and I was easily hitting 1200F on EGT and sending the coolant temp through the roof, but also had more boost, 10lb, from the later combustion. I've thought of replacing injectors and getting the pump rebuilt, and if I'm that far, I might convert to 4911 pump and 6.5 injectors. I would like to be able to use the A/C, cruise at 70-75 mph AND pull my trailer. After all, it is only money and I can't afford a new truck. :D