GMC / Chevy Project Dual Sport ; 1998 GMC Sierra

[Maverick]

I always thought a mid-90's 2dr blazer/tahoe with a 6.5 and sas built like yours would be a cool rig.

 

[Greg]

I always thought a mid-90's 2dr blazer/tahoe with a 6.5 and sas built like yours would be a cool rig.

For sure! Toss an NV4500 in there and you'd have a winner!

 

[Karnage Fab]

ive been building a few sets of motor mounts for a cummins 4b to bolt right into a 98 chevy 1500, my friend is installing one with a nv4500 in his truck, he has another one with a 4b already installed, u should go that route.

 

[Greg]

ive been building a few sets of motor mounts for a cummins 4b to bolt right into a 98 chevy 1500, my friend is installing one with a nv4500 in his truck, he has another one with a 4b already installed, u should go that route.

Like I said, I'd rather stay with a smallblock Vortec.

The Cummins 4BT is a neat engine, but if I was going to swap in a 4 cyl turbo diesel I'd use the Isuzu 4BD1T. It runs smoother and quieter than the 4BT and has a much more usable RPM range. They can be built/turned up to make 400+ ft/lbs, which is plenty.

I had a 4BT that I was going to swap into my old '92 FJ80... even after getting the engine, it's an expensive swap. Motor mounts would be the least of my worries with a diesel engine swap!

 

[ORD Stephen]

I've pretty much decided that the only motor swaps that make sense for a GM truck (and maybe just about anything) are a 6.0L or a cummins. Justification for this is that the 6.0L is pretty cheap to swap and easy to get 400hp from in a very smooth and reliable package. The cummins just seems to be the answer to any diesel swap. You idea of building up a vortec 383 would probably work for what you need, I know I've been happy with the couple stock trucks I've driven with the vortec 350. Just watch the budget, a junkyard 6.0L with a cam doesn't cost a lot...
Our UAK2500 was bought specifically to avoid some of these problems, mostly in that we got a vortec 454 and NV4500 in stock form. It has 5.13s and runs 37-40" tires and could easily run 4.88s since the motor torque is good and freeway rpms are a bit high. The downside is the milage is annoyingly easy to calculate since we can't ever get far away from 10mpg. This last trip on 37s saw a high of 11-ish and a low of 4-5mpg from a tank run out in almost all sandy roads. The solution is simple, just carry more gas! We put in a 40 gal. suburban tank and sometimes carry a couple cans but I'm pretty sure a cummins in this package could pull 15 or a little better on the highway and a lot more on the trail too. I doubt a 6.0L would do much better for milage, my sister in law's 6.0L truck struggles to pull 15 on a road trip in stock form. Built like the 2 trucks we're talking about I'd be really happy with 12.

If you can pull 400hp from the vortec 350 platform and not have to change exhaust, motor mounts, cooling system, accessories, wiring, etc, it's probably the way to go and will work great. I don't know what the output of the vortec 454 is but that power level is really nice. It carries hills well in high gear and has good power for sand, mud and so on.

 

[Tacoma]

^^ all of that is correct. I am getting a very annoyingly consistent 10-12mpg out of my Burb: w/4.10's and 315's, or 5:13's and 37's, it doesn't seem to matter. That's what it gets and I'll like it. Or, put a Cummins in.

If gas was cheaper I would love a 454 in everything, the torque is rad, but the weight and sub-10mpg sucks. 6.0's make a ton of sense and aftermarket support has gotten to be awesome. Cam it, chip it, yeeeee ha

 

[Greg]

I've pretty much decided that the only motor swaps that make sense for a GM truck (and maybe just about anything) are a 6.0L or a cummins. Justification for this is that the 6.0L is pretty cheap to swap and easy to get 400hp from in a very smooth and reliable package. The cummins just seems to be the answer to any diesel swap. You idea of building up a vortec 383 would probably work for what you need, I know I've been happy with the couple stock trucks I've driven with the vortec 350. Just watch the budget, a junkyard 6.0L with a cam doesn't cost a lot...
Our UAK2500 was bought specifically to avoid some of these problems, mostly in that we got a vortec 454 and NV4500 in stock form. It has 5.13s and runs 37-40" tires and could easily run 4.88s since the motor torque is good and freeway rpms are a bit high. The downside is the milage is annoyingly easy to calculate since we can't ever get far away from 10mpg. This last trip on 37s saw a high of 11-ish and a low of 4-5mpg from a tank run out in almost all sandy roads. The solution is simple, just carry more gas! We put in a 40 gal. suburban tank and sometimes carry a couple cans but I'm pretty sure a cummins in this package could pull 15 or a little better on the highway and a lot more on the trail too. I doubt a 6.0L would do much better for milage, my sister in law's 6.0L truck struggles to pull 15 on a road trip in stock form. Built like the 2 trucks we're talking about I'd be really happy with 12.

If you can pull 400hp from the vortec 350 platform and not have to change exhaust, motor mounts, cooling system, accessories, wiring, etc, it's probably the way to go and will work great. I don't know what the output of the vortec 454 is but that power level is really nice. It carries hills well in high gear and has good power for sand, mud and so on.

Sounds good Stephen, I appreciate your input! You know, a 6.0 isn't a bad idea... a Vortec 383 is going to cost a pretty penny to build, I'm thinking $2,000 is just a start. For that price, I'm sure I can get a used 6.0 and pay for a wiring harness. I wonder how easy it will be to wire up a 6.0 in place of the Vortec 350? Making it bolt up isn't an issue, just the wiring. Time to do some research! I know the 6.0 runs thru the gas... but I think any gas engine in a big truck on 37's is going to. The hard part is all the additional stuff, radiator, A/C, etc... adapting all that stuff makes the Vortec 383 look good. I think in the end, the cost will be an even split... and the 6.0 will require more work & effort.

I wish I could have found a extended cab, short bed with a Vortec 454 and a NV4500... I would have been all over it! Part of my idea with this build was to take an every-day common truck and build it up in a simple way that others could follow. I think we've accomplished that.

I do like your idea of swapping in a Suburban tank for more capacity, I think I'm going to follow your lead on that one!

 

[Tacoma]

You can build 383's pretty cheap these days-- depends on HOW, and what parts you throw at it.. all of which is nearly a moot point with LS motors getting cheaper by the day. Cam, headers, VROOM. Cheap and easy.

Suburban tank swaps are the snazz for GM trucks. That was my plan for my old dually: one big 40gal Burb tank instead of the two saddle tanks. Current Burb has got the big tank, I think it's 38gal? It hurts to fill it up. A LOT. But you do get some range....

 

[Greg]

You can build 383's pretty cheap these days-- depends on HOW, and what parts you throw at it.. all of which is nearly a moot point with LS motors getting cheaper by the day. Cam, headers, VROOM. Cheap and easy.

Suburban tank swaps are the snazz for GM trucks. That was my plan for my old dually: one big 40gal Burb tank instead of the two saddle tanks. Current Burb has got the big tank, I think it's 38gal? It hurts to fill it up. A LOT. But you do get some range....

I've been pricing out the 383 parts for awhile and have a wish list on Summit Racing. I've got a Scat rotating assembly with 6" I beam rods, Hypereutectic pistons and a cast crank for $1,100. Lunati roller cam, Fluidampr and gasket re-ring kit... all together totaling right at $2000 and I still don't have stuff like oil pump, timing chain set, cam bearings, etc. I'd also need to have the heads rebuilt, all the block cleaning & machine work done, etc, etc. There's a very good chance a 383 will end up costing over $3000... That's a bit more than I had hoped.

I'm still trying to figure out the best choice for the money, but the 6.0 is looking pretty good, if the wiring, the cruise control and connecting gauges isn't a nightmare.

 

[LT.]

This is one of those decisions that i hate. Do you spend a little more money on something that is easier or, do you spend less (at least initially) and deal with the headaches. Your truck has a theme of being simple, stout, and in your words, something anyone can follow and build. With that in mind i think you have to go with the 383. If you wanted to deviate from your theme then the 6.0 is your best option.

I guess if ot was me i would just buy a 383 already built from Summit Racing. Less down time for the project, easier, and simple. With the 6.0 i suspect that while you may save up front it will cost more than the 383 in the long run. Nickel and dime you til it runs.

LT.

 

[TRD270]

I'd also need to have the heads rebuilt,

I remember hearing from somewhere it's actually cheaper to just buy new ready to go heads for these because they are so common. I also remember a problem with the heads cracking. However I may be thinking of the 5.3, something to look into anyway

 

[Rot Box]

Have you considered forced induction vs. The 383/6.0 option? I have a friend who installed a Vortech blower on his Vortec 5.7 back in the day and it made a substantial difference in power...


That said I'd leave it alone. When are we having this fullsize party anyway

 

[Greg]

This is one of those decisions that i hate. Do you spend a little more money on something that is easier or, do you spend less (at least initially) and deal with the headaches. Your truck has a theme of being simple, stout, and in your words, something anyone can follow and build. With that in mind i think you have to go with the 383. If you wanted to deviate from your theme then the 6.0 is your best option.

I guess if ot was me i would just buy a 383 already built from Summit Racing. Less down time for the project, easier, and simple. With the 6.0 i suspect that while you may save up front it will cost more than the 383 in the long run. Nickel and dime you til it runs.

LT.

For sure! And with that kind of money, I want to make the right decision. The ready to run 383's are more for muscle cars, they're not EFI friendly engines and they're pretty aggressive. On top of that, I really enjoy picking out the individual parts and building the engine myself.

I remember hearing from somewhere it's actually cheaper to just buy new ready to go heads for these because they are so common. I also remember a problem with the heads cracking. However I may be thinking of the 5.3, something to look into anyway

Very well could be the case, I've heard the same thing about aftermarket Vortec replacement heads now that you mention it.

Have you considered forced induction vs. The 383/6.0 option? I have a friend who installed a Vortech blower on his Vortec 5.7 back in the day and it made a substantial difference in power...

That said I'd leave it alone. When are we having this fullsize party anyway

I have! There's actually a slightly used Vortec 350 Whipple for sale locally, but it's $2500!! On top of that, I'd be paying for high octane fuel... if I'm going to do that, might as well pay for diesel, right?

My engine has some miles on it and it's tired... boost would just put a bullet in it. If I were to supercharge it, I'd want a rebuilt engine... so I'm pretty much back at square one.

You're the full size party planner... whatcha got?

 

[Tacoma]

I agree. Even a cheapie stroker is going to cost some coin. I say go w/the 6.0. and a cam, and enjoy.


Also, saw a pretty sweet near-clone of the RME TJ at whatever establishment is on the corner of 13th and State, but didn't get a good look at it. Enough to see that it was sweet, and dark blue. .

 

[thefirstzukman]

After the conversion have you measured the wheelbase? I want to rebuild my 97 stroker that is a duel cab duel rear wheel for the same use. I'm planning on 37" tires and want to shorten the wheel base 24" or so. My goal would be to be able to run hole in the rock with it and there are a couple parts I can think of that might be iffy at that wheel base.

If you could hurry and run the trail and let me know how it does I would appreciate it

 

[Greg]

I agree. Even a cheapie stroker is going to cost some coin. I say go w/the 6.0. and a cam, and enjoy.


Also, saw a pretty sweet near-clone of the RME TJ at whatever establishment is on the corner of 13th and State, but didn't get a good look at it. Enough to see that it was sweet, and dark blue. .

I don't know that a 6.0 is the final answer... I'm still undecided what to do about an engine, we will see. The current Vortec 350 runs fine and I'm in no rush to tear the truck down again soon, I want to get out on the trail with it!

After the conversion have you measured the wheelbase? I want to rebuild my 97 stroker that is a duel cab duel rear wheel for the same use. I'm planning on 37" tires and want to shorten the wheel base 24" or so. My goal would be to be able to run hole in the rock with it and there are a couple parts I can think of that might be iffy at that wheel base.

If you could hurry and run the trail and let me know how it does I would appreciate it

I'll see what I can do about running HITR for you.. I haven't measured the WB, but I should be right around 142-143". I will try get a specific answer for you.

I would think a long fullsize like this with around a 140" WB and 37" tire would do fine on HITR. It's a big truck though and there are some tight turns & narrow spots. I think the wheelbase and approach angle would be helpful, my trailer hitch would probably drag on some of the steep descents. Rock sliders would probably be wise, but probably wouldn't even get touched.

 

[sixstringsteve]

After the conversion have you measured the wheelbase? I want to rebuild my 97 stroker that is a duel cab duel rear wheel for the same use. I'm planning on 37" tires and want to shorten the wheel base 24" or so. My goal would be to be able to run hole in the rock with it and there are a couple parts I can think of that might be iffy at that wheel base.

If you could hurry and run the trail and let me know how it does I would appreciate it

I'd be more worried about the width of a duallie on HITR than the wheelbase.

 

[thefirstzukman]

I'd be more worried about the width of a duallie on HITR than the wheelbase.

I will go to a single rear wheel. Its just better for me to start out with the truck I have, no power questions and already has a 60 up front.

Gregs truck truly is inspiring!!

The wheel base I would be shooting for would be at 140" ish. so I am looking at a short flatbed. I like your interior changes, I would do buckets in the front for sure and with the duel cab I will still have room for the rug rats if they chose to come along.


This is by far my favorite truck build to date. Althought Steves extended cab would be a close second.

 

[sixstringsteve]

aside from the motor/power/mpg, how are you liking the truck Greg?

 

[Greg]

aside from the motor/power/mpg, how are you liking the truck Greg?

The motor/power/MPG's aren't that bad... just could be better.

I'm happy with it, but it still needs a steering stabilizer and an anti-sway bar to help out with on road driving. I still need to get the exhaust finished and build a front driveline before I can take it out and actually use the 4 wheel drive. I'm really looking forward to some off-road driving with the truck, I think it will be quite capable and hopefully ride well in the rough stuff.

There is plenty of other stuff to work on too; I've got a front axle seal leaking, need to wire up the ARB compressor, set up front bump stops, etc.

I'm kind of taking a break from truck, with Christmas coming up and my wife's B-Day I won't be buying any truck parts... so it's not getting wrapped up. I'll get back to it after the new year.