350 Vortec vs. 6BT

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pharmd

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Hello all,

I own a scrambler with a 350 Vortec. I have 1 ton running gear. My frame is 1/4 wall 2x4. So that's out of the way.

My question is this, what mods would I have to do to a 6BT 12valve to make me totally forget about my 350?

Ultimately, I am looking for a very simple (i.e. minimal electronics) no nonsense, reliable drivetrain. Can I get this with the 94-98 12V P-pumped motor?

I was going to run an SM465 with the 1.5" upgraded input shaft. I was thinking about eventually making it a 400hp sled. I like power, but only reliable power.

This project started off as a possible 4bt swap, but I know I will hit a ceiling with that motor. The jeep will weigh 5000lbs +/- after the diesel is in place.

Ask any questions. Let me know if I missed any important info and I will add it.

Thanks for any info.
 
pharmd said:
The jeep will weigh 5000lbs +/- after the diesel is in place.
Click to expand...

It will be extremely nose heavy.

I've wheeled a cummins powered truck. Never again. I've never figured out why the rock crawler guys seem to think they would be so great in a buggy or off road truck. If it were me, I'd be running an aluminum motor with some setback to it to make the weights a little more proportionate.

There is a thread over on pirate about a guy who has done the swap. I'll have to see if I can find it back. If I do I will post it up.
 
I use the scrambler mostly as a work truck. I use the pickup bed to haul, and I tow with it. I weekend wheel it occasionally (east coast). It is by no means a hardcore wheeler. I am looking for economy and power. I get 15mpg on the highway now with 37" tires, 4.56 gears, 4L60. I am looking to be in the mid 20's when I keep my foot out of it, and I want the power on tap for when I need it. By weight distribution on the vehicle now is almost 50/50 with a full tank of gas.
 
So youre planning on going over 1000rear wheel hp in the 4bt? cause thats been done. Heck there are a few over 500rear wheel hp on 4btswaps, what kind of power are you looking for?

I would definately go 4bt over 6bt in that application.
 
400 reliable HP. I am looking for upgrades that will give me some economy when I am not driving like racecar driver. But, I want the power on tap. It seems to me that 400 reliable HP in a 4bt, is uncommon.
 
Go on, I'm listening...

What turbos, how much cash, mpg, pump, etc.???

I am all ears.
 
What is the total towing weight?
If over 11,000 Id say go for the 6bt, below the 4 bt can do it and possible get better mpg.
also I 'd go with a turbo 400/gearvendors over the 4l60.
Talk with peak performance.
 
I would be using a 6bt, upgraded sm465, overdrive and np205. I am about 5klbs and the towing will be around 5-7klbs. I am looking for a diesel horsepower number to compensate for the engine that is in there. I heard that because of the diesel torque, diesel hp and gas hp are apples and oranges. The only diesel I have driven was a 240D and that is not a good example of power.


Don't want to downgrade. (300-400 very reliable efficient HP) I want to have better performace than the engine I have now.

Want better MPG while driving normal, and good power when I want to play.

I am looking for super simple. I don't want alot of electronics.

I like the idea of it (6bt) being fairly unique.
 
carcrafter22 said:
So youre planning on going over 1000rear wheel hp in the 4bt? cause thats been done. Heck there are a few over 500rear wheel hp on 4btswaps, what kind of power are you looking for?

I would definately go 4bt over 6bt in that application.
Click to expand...

You shouldn't be too far from 1k with your Fizzy!

I agree...4B over 6B! With 400hp on the ground I'm going to guess the torque would be at about 850ft-lb....more than enough to slightly aggravate some 8000lb diesel pickups. LOL
 
4B for that application. You'd be pretty pissed off the second you left the pavement with a 6B. It'd be way too heavy. A reasonably built 4B will do everything that small block can and then some, no problem.
 
I personally run a 4bt in a Dakota and if I was shooting for a reliable 400hp, good mileage, and only did some mild weekend wheeling I would go with the 6bt. I would do it for the same reason I swapped out the 4bt for the 6 in the race truck... money Its cheaper and easier to go with the six that has a P pump and two more cylinders and just run a mild tune on it. :Cheer:
 
Toolmanoffroad: That's what I was thinking. I am weighing the pro's and con's before I buy.


the cons for the 6bt are weight, and fabrication to make it fit.

The con's for a 4bt are: if I am not happy with the power, I will hit a ceiling where it will get extremely expensive get more HP, lack of availabilty, cost.

The pro's for the 6bt are availability, easier to make power, and I feel that the engine will not be stressed as much distributing the power over 2 more cylinders.

Pro's for the 4bt are: better MPG, easier fit, possibly more manageable.

I dont mind doing the fabwork in the beginning if I get a more reliable rig in the end. I feel that the super 4bt's that I hear about seem to involve alot of race parts that seem to contradict the idea of DD.

Please let me know if I am mistaken.
 
Depending on how easy you can find a 4bt and the price, I would think you would end up at twice the cost to put in the 4. I love my 4bt, but for 400hp daily driven and on the cheap... 6bt all the way. And I wouldnt use fuel mileage as a factor, cause with either one your gonna love it. From my personal experience the 4bt shakes more, is louder, and its harder to find one as cheap as you can get a 6bt with a P-Pump. It comes down to making the 6 fit..

I think you would be poopin kittins at 300hp with a diesel in that rig BTW.. :evil
 
300 HP is more than I have now, and with alot of extra torque. I set the bar high, but I would probably stop at 300ish. Other options to replace the 350 were a 383 stroker. The 6bt seems to be alot better choice than that. Also that is $5k without anything included.

Was going to sell the Vortec 350/rebuilt 4l60/ rebuilt np241, computer /wiring, radiator everything to just bolt this up into another vehicle to finance the 6bt. That complete package should sell well. Hook up a few wires and you are done..

I really want the 6bt to work. Plus I am sick of all the engine electronics on the chevy. They seem too fragile to me. (replacing O2 sensors, Maf sensors, blah blah.) It gets old.
 
Dave at PDR has a twin turbo 4bt in his 74 Bronco. Drives it down here to the states on a regular basis, wheels it. Drives it constantly up in Canada, to and from work and such. Goes out in the dunes with it. Has the power you are looking for, and he did all of the fab work himself in his own garage. I don't know what he has into it money wise. But I'm sure he didn't brake the bank.

Sounds like you're stuck on a 6B though, so just go with it and find out for yourself.
 
I'm currently building another HO-4B, the pump is the most expensive part of the whole project. I would advise anyone looking for big power out of a 4B to buy an engine with a P-Pump already on it.
 
carcrafter22 said:
So youre planning on going over 1000rear wheel hp in the 4bt? cause thats been done. Heck there are a few over 500rear wheel hp on 4btswaps, what kind of power are you looking for?
Click to expand...

you have any dyno sheets or video of this?

I have never heard of a 4bt making that kind of power...
 
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