2002 questions, new to cummins

[RJPotts]

Hello all. I recently purchased a 2002 3500 QC 4x4 6-speed. I love it, but I have a few questions.

Since I drove it off the lot about a week ago I have done a 4" straight pipe, BHAF and the silencer ring delete option. Pyro, fuel pressure, and boost gauges will be here shortly.

-What is the maximum I can do on a stock clutch, I don't want to get crazy YET, but I will eventually. Just a few small things to increase power, and most importantly fuel economy (avg. 22mpg now 70% city/30% hwy. )

-What are some important dos and don'ts of cummins?

Only thing I'm not sure about, a few times, usually on the highway when I'm kinda coasting for a while or as the RPMs come down gradually, when I hit the go pedal again it does nothing, I can't hear the turbo anymore but everything else seems and sounds fine, it bogs down for a few seconds then suddenly the turbo spools back up and it takes off like a rocket. Any clue as to what this is????

Thanks a lot in advance...

 

[DTroy]

Well, I get to be the first to welcome you aboard. Glad you could join us.



As far as the clutch goes. . I had 275 injectors, boost controller, 5" exhaust, and an AFE. All was fine. When I added the Blue Chip FMS, it was okay at 30%. When I bumped it up to 63% and hammered it up a hill... . well, it went up in smoke. I had prepared myself for the failure, but not the replacement price tag.



The boys have had different amounts of luck with their stock clutches. Mine had already had about 99k on it.



If I remember correctly, the stock clutch is rated for something like 625 ft. lbs. or so.

 

[Mundgyver]

I am at 140,000 with a stock clutch and mods. See my signature. Mine is still holding, but I am starting to put my nickles asside for a new one. Driving style makes a big difference. Welcome aboard.

 

[Beast2B]

There is LOT of variation, mine slipped with BHAF, 4" exhaust and Comp on level 3 (of 5). I only had 25k miles, but I was planning to BOMB it anyway, so it wasn't too big a deal. I'd say that besides BOMBing, the front end is probably the worst thing on these 4x4 trucks. Look into a DSS steering support and you'll probably want to upgrade the track bar before too long. Search and you'll be rewarded with hours of reading! I did the DSS bracket, tightened it up a bit, more preventative than repair for me.

 

[Tcolesanti]

As far as the slight "dead pedal" you get after coasting, it could be a number of things, i. e. not being used to the 24v yet, could be an APPS needing to be reset or replaced. To do this disconnect the batteries for an hour or so, then hook them back up, turn the key to "on" and slowly depress the accelerator pedal all the way down and slowly all the way back up. Check lift pump pressure as soon as you can, catch it before it causes a really expensive failure. I recommend the FASS as I have one, works great and I would buy it again. Hope this helps.

 

[Tcolesanti]

Also, fill out your signature when you can, so people will have a quick reference to help you in the future.

 

[RustyJC]

My stock clutch lasted through an Edge EZ, BHAF and 4" exhaust system, even towing a heavy 5th wheel. When the DD2 injectors went in on top of these mods, however, the stock clutch slipped the same morning - at 1800 RPM in 5th gear of a 6 speed running empty!! :{ That was at 16K miles. :{ :{



As far as the dead pedal goes, I'd certainly check lift pump pressure ASAP. My HO, however, before I installed the EZ, was soft below 2100 RPM, then came on much harder. This is part of the low emissions fuel curve calibration of the stock ECM to keep the engine from overfueling before boost is building up - this keeps smoke down, but also kills a lot of responsiveness.



Rusty

 

[RJPotts]

Well thank you all for your input. I was afraid that the lift pump was going to be the problem, but I have an extended warranty so I'm not too worried about the bill as I don't have any fuel system mods to void the work. Other than that little bog every once in a while, it runs great, has a little stumble when accelerating cold but I'm not worried about that.

I have noticed that a lot of people here use the Edge EZ or some other Edge product as a base, how hard is it to install/remove this incase the VP44 or something expensive does fail so that I don't get hassled by the dealer about the warranty?

Thanks again...

 

[Tcolesanti]

Where are you located? Maybe a member in your area could help you diagnose the stumble/dead pedal issue? I am using an Edge Comp in my truck and I love the in cab adjustability, but if I were to buy again I think I would opt for a Blue Chip FMS. Edge EZ's are great that they have a certain degree of adjustability (low boost fueling), a built in boost fooler and work well with aftermarket injectors, also the price is good. The EZ is just 2 plugs underneath the hood, one to the MAP sensor and the other to the diagnostic port, makes it very easy to remove in case of warranty work.

 

[RJPotts]

I'm in Buford, GA. I'm still in the process of getting my sig and profile done. Now the question, which mod should I get? Edge EZ, Comp, etc... I haven't looked into any of them in depth... what would be my best compromise between power, fuel economy, and price for my application?

Don't tow much and when I do it's my little Toyota rock crawler (trailer + truck = about 5000lb) Most is regular daily driving 70% city/ 30% highway.

Thanks again in advance

 

[Tcolesanti]

The Edge EZ in most cases will improve mileage a little bit, and like I said before is easy to remove (and undetectable) in case of warranty work. Definately get your gauges installed as soon as you get them, they may not be the most expensive upgrade but by far the most valuable. Your stock clutch will be fine with the EZ, and then later you can upgrade injectors and clutch at the same time.

 

[RJPotts]

Excellent, thank you all very much for your help. Anyone know of a good dealer of Edge products. I've seen them on E-bay for $250-$350 or so, and they seem to retail for around $450-$500. What's my best bet?

 

[RustyJC]

If you get an EZ from a 3rd party, be sure to get the boost elbow Edge supplies with it. This will increase your boost pressure and keep EGTs down.



Rusty

 

[RJPotts]

I didn't know that was included, that is probably why the E-bay ones are so cheap. I think I'll just get a new one to be on the safe side.

-R. J.

I believe my truck has the HO motor, how do I tell? Does it make any difference?

What do these trucks make at the ground from the factory hp/torque?

HO? Non-HO?

And what should I expect, ballpark estimate, with the mods I have + the Edge EZ, and will it make some black smoke?

I like black smoke.

 

[Tcolesanti]

Yes if your is an '02 six speed then it is an HO. The HO engine has slightly higher compression than the SO engine (17. 3:1 vs. 16. 7:1) it also comes stock with the 13" clutch and 1 3/8" input shaft on the six speed. Other differences are with the injection pump and also the ECM. I know from the factory at the flywheel the SO was at 235hp/460ftlbs, the HO was at 245hp/505ftlbs. You could do a search and find someone that had dynoed with just an EZ to see what thier numbers are. I would recommend buying from Piers www.piersdiesel.com

 

[DTroy]

If you don't have gauges yet, you might want to look into the FMS. You will be able to fuel with lots of adjustability... and you won't have to buy gauges.

It comes with an EGT probe and it reads boost pressure. Not to mention all of the features.

I didn't want to alter the timing, that's why I went with the FMS. If the Redline was around at the time I might have considered it instead.

Oh ya, one more selling point. The FMS will tell you if the LP supplied fuel pressure drops too low.



I'm not a fueling box salesman... but I stayed at a Holiday Inn Express last night.



Save yourself some trouble and have the dealer check out the problems before you do any mods. (And to spare yourself a flaming. )

 

[Beast2B]

Ditto the dealer check. My 01 dyno'd 214hp/450# with BHAF and 4" exhaust only. Same day, same dyno I borrowed an EZ and ran 245/580 without the boost elbow. I kept the EZ for a few days and the driveability is WAY better.

Now, on the same note, if you don't want to continue BOMBing your truck;

Don't drive another members higher HP truck,

Don't attend a dyno event,

Don't read any threads about hp, torque, smoke stories, rice burners involved in smoke stories, etc.

 

[RJPotts]

Well thank you all, I'm convinced that an EZ will probably meet my needs for price, felt gains, and driveability. I have gauges on the way but a dealer check will be in my near future, nearer anyways than any new mods. I am planning on doing extensive modifications to this truck, I can't leave anything alone. I'm in the process os spending around $13,000-$15,000 on a $1000 85' Toyota (rock crawler), and thats just "thrown" together by my standards, I didn't even break out my TIG welder for the cage I wanna drive it so bad. BUT... I have a funny feeling that once I start with the old Cummins the 'yota is gonna have to take a seat for a long while.

Priorities are priorities...

Thanks again, any more ideas are welcome

 

[Tcolesanti]

Some quick side notes:

-Take a look at your track bar where it connects to the frame via balljoint-check for sloppiness-it will cause the truck to wander.

-After the warranty is up, consider an aftermarket lift pump of some sort, pusher pump, FASS, Air Dog, Rasp to correct the fuel delivery problem to the VP-44.

-BOMB away!!!!

 

[RJPotts]

I've been reading about the front end issues, I think that may be happening on my truck, steering isn't very precise, kinda sloppy. I'll be fixing that soon I'm sure.

Any one have pictures of stacks, I wanna do some here in the near future, and I'm not sure about what look I like the best. Any and all pictures would be a great help in making up my mind. If you don't want to post them here my e-mail is <rj. potts@ngtinc.com>.

-R. J.