6.2 Power?

[86DuallyCrew]

Is there anything we can do to our the 6.2 in our 86 Crew Cab dually that is relatively inexpensive? Don't want to go to a turbo or anything thats more money that I want to spend. What about IP mods? Is a bigger more flowing exaust worth it? Injectors? What can we do to this thing? We tow a 2 car open trailer that weighs about 9500 lbs. It does ok...steep grades are horrible though. Went racing last weekend about a 3 hour trip with a few big mountains and we were down to 2nd gear going about 20-25 mph. Just wondering if there is anything we can do?


Another question, how hard is it to put an NV4500 transmission in this truck, it already has the hydraulic throwout bearing and it is 2wd so is this a direct swap?

Any help would be appreciated, thanks alot.

[john8662]

You can do a few things to up the power non turbo.

Get more air into the engine, first install a hi-flow air filter. I'd see about getting a Unifoam filter, Amsoil used to make a foam airfilter element but has since dropped that design for a disposable version.

While you're getting more air into the engine you might consider building a better airbox with some kind of a snorkel on it to direct more air into the air cleaner. There is a provision already in the core support of your truck that you can adapt 4" hose from and into your air cleaner.

The factory installed a resonator and restrictive tubing into the air cleaner, this would need to be removed and replaced with some air cleaner tubing to get air to the air cleaner in the first place.

Exhaust work can be done, but I'm still not convinced that the factory needs to be replaced to get more power.

Banks makes a "stinger kit" that has a mandrel 3" exhaust system and the air cleaner box mods mentioned above. It's supposed to net some more HP.

But.. A turbo is really the "fix" for the towing scenario.

Others will likely tune in here soon..

P.S. Welcome to TDP forums!

[Subzilla]

After you do the mods John suggested, the IP can be turned up via the metering screw. More instructions on the Diesel Page concerning that. Make sure you have a pyrometer (exhaust gas temperature guage) installed as soon as possible and keep the egt's under 1200 or so. This is critical to engine preservation. You would be amazed at how quickly the egt's can climb on the hills especially pulling a load.

You've found the right place for lots of great info.

[NH2112]

A turbo is really the only modification that will net you some serious power. Adding more fuel will only work if there's more air to burn it in, and a wide-open air intake system won't flow THAT much more air since it's still relying on atmospheric pressure to do all the work. The difference will be noticeable, but honestly I think you'll go from pulling hills at 20-25mph in 2nd to pulling them at 25-30mph in second. With the turbo you'll be able to pull with the flow of traffic.

I recently went from an NA 6.2l in my 85 C1500 to a 6.5lTD and "night and day" doesn't even begin to describe the difference. If anyone had told me what the new engine would pull like compared to the old one before I did the swap, I would have thought they were full of you-know-what. Search around on eBay, you'll probably be able to find a turbo w/exhaust manifold, and intake for a decent price. My truck also has a 4-speed, so I could tell you what I had to do to make everything fit (it really wasn't that much.)

PS - I have most of an ATS turbo that I'm willing to let go really cheaply. The turbo will need new bushings, and some parts will need to be fabbed. It's a kinda weird design but from what I've heard it's actually a better turbo than the Banks. PM me if you're interested.

[john8662]

Gotta throw my .02 in on the ATS kit...

It works great on 4wd applications, not so great on 2wd trucks, due to the different suspension below.

If you've got 4x4, then ATS, if not go Banks 100%

The ATS will spool faster due to the exhaust housing used and the location and plumbing of the kit. It will also make great boost (almost scary for stock C/R engine).

I also agree that the performance of the turbo verses n/a is night and day.

The good about making a cold air intake (plumbing from the core support into the air cleaner) is that while going down the road, it will get more air, which helps when pulling.

J

[90LX]

Good to see another racer on board!

If you don't want to go turbo, you might want to look into propane injection. I don't know a lot about, other than reading a few web articles on it. There was a good test article in one of the Dodge magazines (can't remember which one) that compared power and mileage with/without while pulling a trailer. They picked up mileage and had more power for pulling. Can't remember if the $ per mile went up or down. Do some research on it. They have kits for NA as well as Boosted.

Link below on Propane kit.

http://www.usdieselparts.com/category.cfm?Category=707

[NH2112]

The problem with propane injection on an NA diesel is you're still adding a fuel without adding more oxygen. The propane doesn't actually burn and create power like diesel does, rather burning it allows for more complete combustion of the injected diesel fuel. The numbers I've seen show that a typical diesel burns 80-85% of the diesel injected, with propane this goes up to about 95%. Still, the propane will be using oxygen that could be put to better use burning diesel. Nitrous would be a better choice since it has more oxygen per unit than air does, and introducing nitrous into the intake air would allow more diesel fuel to be burned, resulting in more power for climbing hills or other short-duration needs.

[soulman67]

On the 91 crewcab srw 3500, it had factory dual exhaust I cut the mufflers off and it made a great improvement on pulling power. It had the 4L80e instead of the granny 4 speed. It was very loud but sounded awsome.

[90LX]

Mopar Muscle magazine had the propane article in the April 2006 issue.

www.moparmusclemagazine.com

[NH2112]

The article refers to installing it on a turbocharged Cummins. Putting propane on a naturally-aspirated engine will have the results I mentioned above because there just isn't enough oxygen available to burn the diesel AND the propane.

[gvig]

The 6.2 exhaust manifolds have a cast in restrictor ring just inside the outlet. I found a set of 6.5 non turbo manifolds (no restrictor ring) and put them on my 84 Sub and it made a dramatic difference, also went with a dual three inch exhaust with dual Magnaflows. The power was dramatic, so was the noise. Sounded like a small block chev with glass packs. A crossover took much of the crackle out of it, still impressively loud. Turned up the pump and it really made some power.

I was pulling a 24 foot Bayliner hardtop cabin cruiser, very heavy, but with the mods, the Sub pulled at any speed asked.

Always make sure the exhaust and intake are maxed out before you add fuel.

Breathe, gauges, then more fuel.

[Tatraplan]

The 6.2 exhaust manifolds have a cast in restrictor ring just inside the outlet.

Would it be possible to grind off the restrictor, or will that weaken the manifold to much?

/Robert

[snoman87]

Another question, how hard is it to put an NV4500 transmission in this truck, it already has the hydraulic throwout bearing and it is 2wd so is this a direct swap?


I see nobody has address this question. The NV4500 would be easy to put in. You may have to run a little extra piping for the clutch, and make some minor adjustments to the driveshaft and tranny mount location but it will bolt to the engine so your laughing. You will love to have OD

[gvig]

As for the restrictor rings, I imagine they could be ground out. Would take a lot of time and a die grinder, much like porting a set of heads. Shouldn't significantly weaken the manifolds if you watch what you are doing and don't make the wall any thinner than the surrounding area. Any relief would help.

I considered doing this very thing, but decided my time was worth more than the small amount I paid for the manifolds. It was some time ago and I don't remember how much I paid for the manifolds but it was something like $25 or $30. YMMV!

First the memory goes, and then.... something else... but I don't recall what it is...:D

[86DuallyCrew]

Thanks a lot for the ideas guys, will look into getting more air to it and maybe a more free flowing exhaust, probably will buy a turbo diesel truck before I ever spent the money to put a turbo on this truck, its just not in good enough shape.