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have you driven your 4bt more than down the driveway?

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Discussion Starter · #1 ·
i want to hear from anyone who has actually DRIVEN thier 4bt swap. especially with 700R4 or other OD auto.

i want to know if it will beat my bicycle off the line in a 3800# truck.

can i make a pass at 55mph without 2 miles of running start?

i know i can tow a semi up the hill, but can i pass that same semi?

anyone near nor-cal that has a 4bt i can drive-iin anything inclduing original application.
thanks
feel free to PM me or what have you.
thansk!
 

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Well, I've not swapped mine out of the P30 yet, but I've been enjoying driving it here and there..

The pump on mine has been adjusted to allow higher RPM for greater max speed on highway. It has NOT been adjusted for greater power (according to the service manager at Frito Lay, and I believe him). The truck is a 15' box P30. I've not taken it to the scales yet, but I think the thing weighs a bit more than 3800#. That said..

My friend that followed me back from Chattanooga in my pickup when I drove the P30 home swears that the P30 would probably beat my 90 C2500 w/ TBI 350 and 700R4 in the 1/8th. (3.42 rear end, 29" tires, Ex Cab, long bed, w/ bed topper..) I tend to accept his estimates in this area, as he's one of the ones that's been there, done that, and is now using the T-Shirt as a shop rag.. (Yes.. We're thinking a trip to the track is in order. Wonder if I can get the thing to light the rear tires?)

Oh, and that was before I figured out that if I really want to move out quick, I have to manually shift the TH400.

On highway, it's capable of holding 75 on flat and level, and 70 up any hill I've hit so far. Not bad at all for something with the frontal area of a bus.

And it's still pulling strong up until it gets near the governed limit.
 

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4BTA on road

On the road x over 2 yr.
# 7 owned early Bronco, owned 170, 200 six, 289, 302, 351.
4BTA, 68 Bronco, THM-475, 3:50 with 35" tires makes 3:50 gears about same as 2:78 gears with stock tires.

Power is comparable to 289/stronger than 302. I have no problem acceleratign with traffic or faster.

Compared to V8-gets there about the same, gearing clearly has to be higher, less RPM.

Mileage better than six cyl (mine were/ARE gutless).

Noise is obnoxious, till I get beside thumper stereos, then it is sweet revenge.

With no OD, mid-low 20s. Until I OD, top end is little over 75MPH.
No droop in mileage until 70-75. Good mileage at speed I travel, which is 65 or below.

Driven 5-6 known clear days on 1.5 hour morning /evening commute.

I would be using mine for Daily Driver, but have yet to install hinges and modify doors, and getting caught 1.5 hours from home with a vehicle with no doors in Virginia rain is a non-starter. Waited on chrome removeable door hinges for six months. Got em.

Mounting those doors may get on my priority list within the next few months.

Wayne
 

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driven mine quite a bit, it's plenty fast. i'm around 4500 or so, probably more like 46-4700 at this point.

I have not changed the pump or anything and so far I am pretty happy with the performance.

I don't DD mine, mainly because the 700r4 in mine is acting up. Fortunately I don't have to DD it at this point. I will in the future, I plan to run my 98 maxima into the ground first. I commute a lot, 130 miles round trip each day to work.
 

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Mine's in a vintage Dodge, 2WD, roughly 5,500 lbs truck, NV4500, 4.1 gears, 29" tires, bone stock. Removed about a 350-370 horse 360 to install 4BT. If I had to compare I'd say the 4BT is roughly similar to a stock 360 2bbl truck. Some gears it has more power than that, others about equal. I can light the tires from here to Christmas if I want, in 1st or 2nd gear.

On the freeway I'm always surprised at the strong pull from 60-80 mph, very healthy. With a governor spring swap I'm sure it would be pushing 100 hard if not more. PLENTY of power stock, but I'll probably turn it up because of my local roads, plus I already bought the go-fast parts.

Two things: with a diesel you can turn up the fueling for more AVAILABLE POWER, but your throttle pedal still controls that. That means that even with some pretty serious tweaking you can still get the same mileage if you keep your foot out of it! I see 25 in the steep mountains, running pretty hard.

Second: GEARS, GEARS, GEARS!!! That's the secret to the whole driveability thing, you have to have the right gears. That's axle gears, and tranny gears. Get that right and you'll be smiling every single time you drive it, I do anyway!
 

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This is a great thread, I'm learning a lot, and also confirming a lot of what I already knew. I have a '96 Ram Cummins (6b, not a swapped in 4bt), and can confirm the mileage vs. power statement. When it was bone stock I easily got 22mpg (its a 4x4). After a while I put in a different fuel plate (#10) which gave me TONS more power, yet my mileage (when I can behave myself) stayed the same. But I have the extra there when I need it.

The same goes for gears. A Cummins gets great mileage when its in its sweet spot, but the mileage goes down the toilet in a hurry if you get out of that even a little. My Ram had 3.54 gears stock, and thats when I was getting 22 mpg. I now have '04 Ram 2500 axles in it with 3.73 gears. Not a big change, but on the highway I lost at least 4 mpg. This truck isn't used a lot for towing, so I wish I had the 3.54 gearing back. On the other hand, around town, where I need to accelerate a lot, I'm getting at least as good as I did with the 3.54 gears.

For our Durango project, which will be used as a commuter vehicle with very limited trailer towing (towing my XJ on a trailer to trail runs a few times a year), I will have 3.54 gears for now, but I'll be changing to 3.27 eventually. Ideally, I wish I could use 3.08/07 for economy. This will be with a 4bt/NV4500 combo in a 4x4 with 31" tires.

Please keep the good info coming...its a great help to those of us starting on our projects!

Jim
 

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Discussion Starter · #8 ·
This is a great thread, I'm learning a lot, and also confirming a lot of what I already knew. ...
...............
Please keep the good info coming...its a great help to those of us starting on our projects!

Jim
wow gentlemen! this is super great info. my plan is for a classic suburban (50's) with 4bt(i hear 4BTA=quieter?) and S-10 4x4 axles with 3.42 ratio, and 700R4 and 235/75-15 tires on a slightly lower than stock chassis.
this is going to be the 'sleeper' driver and my wifes MAIN car and the only reason for 4x4 is because with this body-i cant chain up when going to the snow(boarding) or up in the mountains to the inlaws.
it will occasionally tow a small pickupbed trailer and my car trailer in rare emergency situations.

also-curb wieght for this exact body in 2wd with SBC/700R4/camaro suspension is right at 3800#

3.42 ratio axles are stock in S-10 axles. should I be thinking about 3.23 or even lower ratios? I will be having the OD 700R4.
Thanks again and KEEP IT COMING!
Mark
 

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My Carryall can run any legal road speed and is very reasonable when passing someone, but its not a Vette LOL. Its also equally capable off road.

I took it on a trip to Labrador in 2005, ( http://imageevent.com/moosecreekmaple/translabrador2005 ). Loaded with 2 extra axles, spare parts, tools, 20 gallons of extra diesel, 8 gallons of pre mix anti freeze, 2nd spare tire 900 x 16, clothes, back pack and tent, my curb weight was a little over 7000#.

The total distance was 3411 miles with 539 miles being on primitive gravel roads running at 20 or so MPH for hours due to serious poor road condition. My overall fuel for the entire trip was 25.9115 mpg.

I use 4BTA's, CPL 857 turning a NV-4500 married to a NP-205 turning 4.89 ring and pinions cranking 900x16 STA Super Lug Tires 36" dia. Before you ask, why 4.89's, Power Wagons. WC's and M37 stock differentials have either 4.89 or 5.83 Ring and Pinions only.

I am now in the final stages of my M37 with exactly the same engine driveline as the Carryall and expect even better performance since its a lot lighter.

Paul

 

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My Carryall can run any legal road speed and is very reasonable when passing someone, but its not a Vette LOL. Its also equally capable off road.

I took it on a trip to Labrador in 2005, ( http://imageevent.com/moosecreekmaple/translabrador2005 ). Loaded with 2 extra axles, spare parts, tools, 20 gallons of extra diesel, 8 gallons of pre mix anti freeze, 2nd spare tire 900 x 16, clothes, back pack and tent, my curb weight was a little over 7000#.

The total distance was 3411 miles with 539 miles being on primitive gravel roads running at 20 or so MPH for hours due to serious poor road condition. My overall fuel for the entire trip was 25.9115 mpg.

I use 4BTA's, CPL 857 turning a NV-4500 married to a NP-205 turning 4.89 ring and pinions cranking 900x16 STA Super Lug Tires 36" dia. Before you ask, why 4.89's, Power Wagons. WC's and M37 stock differentials have either 4.89 or 5.83 Ring and Pinions only.

I am now in the final stages of my M37 with exactly the same engine driveline as the Carryall and expect even better performance since its a lot lighter.

Paul

Very nice truck there. Looks like it was a lot of work.
 

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Very nice truck there. Looks like it was a lot of work.
Thanks Mooktank;
It took 2 years to rebuild. The entire lower half of the body was replaced. No sheet metal is available for the old iron. All was fab'ed from new sheet. Many criticle measurements were supplied by two friends one in Fairbanks and the other in Seattle. Full pictures of the rebuild at; http://imageevent.com/moosecreekmaple/1943dodgecarryall

Paul
 

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The burb I just got running has great off the line, preboost power and under boost out pulls the TBI 454 it replaced. Best of all it uses half the fuel.
 

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I only have about 100 miles on my 'burb so far, got it running just a few days ago. I have propane injection on it, it really boosts the torque. I am very pleased with the power. I need to remap the throttle so that I don't have to let up on the go pedal to get it to shift. A friend has the TunerPro software and burner to rewrite the firmware for the trans. I have the oil filled mounts, but still have alot of vibration at idle. I will experiment with a propane bleed at idle when in gear, but don't have alot of hope to be able to smooth it much. It will go 79 mph, the pump is governed at 2900.
 

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I am currently getting high 20's low 30's mpg and the jeep flies now. I put a smaller housing on the turbo. passing is now something I just do instead of downshifting. this is by far the best thing I have done to my jeep and none of the concerns people constantly talk about panned out to much (it's loud, it rattles, it's heavy, it's tall.) I took care of the rattling by turning up the idle a hair. I soundproofed the firewall and tub, I put heavy springs on the front and the engine just fits like it was meant to be. There took care of all of the so called "problems". name one jeep engine that bolts to a 1 ton OD trans, get's 30mpg, makes 300ftlbs, and last almost forever. And to top it all off they are relativly cheap.
 

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Discussion Starter · #16 ·
I am currently getting high 20's low 30's mpg and the jeep flies now. I put a smaller housing on the turbo. passing is now something I just do instead of downshifting. this is by far the best thing I have done to my jeep and none of the concerns people constantly talk about panned out to much (it's loud, it rattles, it's heavy, it's tall.) I took care of the rattling by turning up the idle a hair. I soundproofed the firewall and tub, I put heavy springs on the front and the engine just fits like it was meant to be. There took care of all of the so called "problems". name one jeep engine that bolts to a 1 ton OD trans, get's 30mpg, makes 300ftlbs, and last almost forever. And to top it all off they are relativly cheap.
wow-cool!
so im not really a 4x4 guy and want to know-does jeep make a IFS 4x4?

my plans are for a 4wd(3-5 days/year snow on paved roads) with IFS. prob gonna run chevy but open to anything IFS...with 60" WMS-WMS
will be installed in 50 chevy suburban.

do you have video capability? post or email me a short<2min video of it running. what did you use to soundproof? i am thinking of several spray-applications as well as interior matting and carpet. this is going to be a dailly driver and MPG as well as the ability to pass in less than 1/2 mile are the primary motivators.
thanks
mark
 

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Curious...Why do you need IFS? Bar None - the only good stock IFS system is the H1 geared hub setup.
Amen to that!!! The only reason I'm keeping the IFS in my wife's Durango is because its her daily driver, and I need to keep it at stock height. Properly set up, a solid axle will give a good ride. Anybody driven a Grand Wagoneer? They ride like a 4x4 Caddy! Solid axles have almost no maintenance required (ball joints last easily 100K+ miles), while IFS requires frequent ball joint replacement. IFS is also very weak. 4x4 IFS tend to eat CV joints fairly frequently as well. Not to mention frequent alignments. I'm a mechanic, and our regular customers need to come in once a year to have their IFS 4x4s aligned, and they always require adjustment each year (very rough roads up here). In comparison, we get 10+ year old trucks with solid axles that have never had anything except minor toe adjustments.

Jim
 

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Discussion Starter · #19 ·
Curious...Why do you need IFS? Bar None - the only good stock IFS system is the H1 geared hub setup.

okay-so now im a little curious. i LOVE the ride of stock 50's leaf springs but also think IFS is an upgrade for dailly ride handling...
Argghh...

this will see less than 10 days/year in 4wd. and all of it on paved snowy roads.

it wont be getting a lot of miles in general maybe 3-5,000/year if that. we work out of home so...

the other thing is that i want it to ride stock hieght of the 2wd 50's or even 1-2" lower for appearance.
s-10 comes with 3.42 ratios pretty common and coupled with road tires and with OD trans-should sit in the sweet spot of 17-1800 at 65.

im a big fan of the depndability of a solid axle but... convince me. the s-10 i can mod to not be torsion bar pretty easy and have air ride to handle the extra 300# of teh motor.
and the s10 front frame section matches almost exactly.
so far its a head project so...

keep it coming! im new to this and know zero of 4x4. just a great designer and fab guy-i can make it work but dont want to invent that round padded conveyance... =) wheel is it?! ROFLOL!
 

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IFS has its place, for very mild street driving, and gives a good ride and handling when set up properly. But for real reliability, you can't beat a solid axle. Honestly, it sounds like you would be safe with IFS as a low mileage/year vehicle that will be driven fairly easily on good roads. Unfortunately, the setup you are looking at has to be one of the worse IFS setups designed. The S-10 ball joints are stupidly weak (usually last 20-40k miles up here before getting very loose), and thats under the weight of an S-10 with a V-6 (or even 4 cyl.) Dodge IFS ball joints are very close as far as strength (Dakota/Durango), and I'm quite concerned about our Durango when its done, but as a mechanic, it will be fairly easy for me to replace them. As an example of how bad they are, we had a customer come in for an inspection with a 1 year old Dakota with 18k miles on it. Knowing the design as well as I do, I checked the front suspension carefully, and found 3 out of the 4 joints bad! 2 of those were VERY bad.

Try looking at some of the fullsize truck setups. late 90's Chevys are probably the best, they rarely seem to wear out parts other than wheel bearing assemblies...and even those aren't a very common issue, just a maintenance thing. If you look around, some models come with coils instead of torsion bars. To make the install easy, get a front clip from the truck you want to copy and use the entire front frame section. That will be much easier than trying to fab up mounts for the diff and suspension. The frame section will also be strong enough for the 4bt, and because GMs use a rear sump oil pan, a rear sump 4bt pan should fit no problem.

One more thing- newer 1/2 ton GMs sit fairly low, even with the tall tires they use. By using smaller tires and possibly using lower springs, you should get the stance you want, even with 4x4.

Jim
 
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