Turning up the IP

[DaveBr]

Looking for some feedback on how much I can turn up the mechanical IP on my 93 2500 2 wh dr. Mods done are as follows: 3.5" exhaust including x-over pipe, pulled intake snorkel & installed K&N filter, homemade adjustable boost control, 5 core rad, Kennedy's 180 calibrated clutch fan, 20" fan blade & 180 thermostat. A-pillar with boost, egt & trany temp. I'm thinking 1/4 turn but to be honest everything I've learned has come from this site & manual's purchased from this site. I'm no expert but I'm learning. Any thoughts?

Thanks

Dave (my first post)

[More Power]

Welcome to the board! :)

There are a couple of practical limits that define how much a pump can be "turned up".

Exhaust temperature.... The 6.5 can run at 1250 degrees F (before turbo) for as long as it takes to pull the longest steepest Interstate grade while towing any rated load. Adding fuel that takes it past the 1250 mark can cause problems unless the driver uses his right foot to manage temperature.

Health and capability of the fuel injection pump.... Most healthy DB2-4911 fuel injection pumps can be turned up approximately a 1/4 turn. An older pump may not be able to. Surging, white smoke, or erratic running are the usual symptoms of a pump that has been turned up past its ability.

On edit: Also, be aware that increasing the fuel rate also advances the injection timing by some amount. The two individual rollers for the pumping plungers ride up and down over eight peaks and valleys inside the cam ring, within the pump. Increasing the fuel rate lengthens the stroke of the two pumping plungers, so they each begin compressing fuel a little sooner on the upslope of each cam peak. This advances the timing - allowing the pumping plungers to pop each injector a little sooner. If your timing is already well advanced, you may need to retard the timing a little. A timing meter would be a big help to track the before/after fuel-rate adjustment's effect on timing.

Jim

[DaveBr]

Thanks for the info. I went 3/16 of a turn and it will be a few days before the truck runs. That was a challenging experience definately not for the faint of heart. My pyro is 1 1/2" below the manifold in the x-over pipe on the left bank. Should I allow the EGT to hit 1200 range or not as it is not directly in the manifold?

Thanks

Dave

[DmaxMaverick]

The X-over pipe is pre turbo, so ~1200° is OK. Only a few degrees off of the manifold, if it's detectable at all. Your boost should also increase accordingly, or you'll be missing out on some power trying to keep the EGT's under control.

3/16 turn is quite a bit. Most increments should be about 1/16 to 1/8 at a time. I know, it's a PITA, and you'd like to get it right the first time. Every engine and pump is different, in my experience, and a little on one may be a lot on another. Much depends on how much room you have to play with on your EGT, the condition of the engine and pump, and stability of the fuel supply.

[DaveBr]

Thanks for the info Jim. Much appreciated. As I said it will be a few days before the truck runs so I will keep my eye on EGT's and hope for the best.

[DaveBr]

Just back from 4,000 mi. test run pulling my 5th wheel & boat in tandem. The truck ran flawlessly. Impressive increase in power & truck never overheated, even on long, steep hills in 90+ weather. Only on extreme steep grades did I have to back off the pedal due to high EGT's. Thanks for all the info.:D

[BIGCHASE90]

HOW DID YOU TURN UP YOUR FUEL INJECTION PUMP??? I HAVE A 93 6.5 turbo diesel CHEVY 2500 4X4 AND not sure how to turn it up

[6.5 Detroit Diesel]

Caps stuck on the computer? :D
Have you done any mods on your truck yet? Essential being exhaust and pyrometer. Turning up your pump without preparing your engine could be fatal.

[BIGCHASE90]

i have a 3in exhaust but im getting ready to put a 4in exhaust and i have an exhaust temp gauge,boost gauge,tranny temp gauge, i havent really done anything to the truck yet i know it sounds stupid but i want it to smoke black.

[6.5 Detroit Diesel]

No excuse needed, it was one of the reasons that "fueled" my need for turning up the IP. Is the pump still in the truck? It is easiest if the IP is already out. :D
On the drivers side, if you look towards the bottom side of the pump, there is a little triangular plate. This has to come off. Your are going to need a allen key, (not sure what size, Robyn?) You will need to rotate the pump until you can see the screw head. Turn the screw clockwise carefully. Most will go 1/8th of a turn, and that will give you plenty of power. 3/16's will give lots of black smoke, and 1/4 is as far as I have read people safely taking it. Hope this helps and have fun digging around. ;)

[DaveBr]

On the opening page of this site click on articles and look up Mikes P400 6.5. There are pics of the IP taken apart and how to turn it up. You can access this if you are a member. I recommend you buy the 6.5 diesel manuals sold on this site. It has lots of info on getting more power out of your rig. Including turning up the IP. Make sure you pull the snorkel out from between the inner & outer fenders before you do this. You can also increase your boost - article in members area or in manual & a DIY intercooler for $400.00.

[BIGCHASE90]

which way do i turn the pump??? and what is a snorkle, is it what supplies the air to the airfilter??? and do i have to take off the fender to take the snorkle off? how do i get more boost out of my turbo saftley cuz i dont have the money to be replacing the turbo if you know what i mean

[bobt]

When I got instructions from Banks for turning up the IP on my '93, they indicated it took a 5/32nds ball end allen wrench.
Bob T

[6.5 Detroit Diesel]

You have to turn it clockwise.
As for the turbo, some vendors here sell stuff for you there. Check out Kennedy's stuff. You can safely make more boost

[daustin]

On the '93 models, you already have a spring actuated waste gate controller. What you need is more spring pressure, on my '93 i took the existing control rod/actuator off and modified it by: taking my bench grinder and removing the lip around the existing spring can. Got some1/4" rod, bent one end n a 90 and drilled it for a retaining pin. Threaded the other end of the rod so i could adjust the spring tension. Easy $10 fix with rod from home depot. Works the same as the turbomasters but a lot less expensive. I wouldn't do that unless you have boost guage as it dosen't take a lot more tension to make too much boost. I also turned up my IP 1/4 turn at the same time, watch your pyro gauge and don't exceed 1250F - you'll have to drive with your foot backing off if the temp gets above that.
Don

[bcbigfoot]

Great article about your boost controller here. http://www.thedieselpageforums.com/tdpforum/showthread.php?t=31044

[BIGCHASE90]

what is a snorkle? is it sort of a pipe that is between the inner fender and outer finder that sends air to the air filter?????????