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Topic Review (Newest First)
07-12-2013 06:32 PM
speedyrev I would think that a LS engine from a late model Chevy truck would be cheaper and simpler.
07-12-2013 05:42 PM
ipboxman I DD my 4bt Scrambler, I routinely get 33mpg with a 5 speed, 3.55 gears & 33" tires. It is a very simple setup, not a lot in the way of swap 'kits' out there tho. I fabricated most of my stuff.
My experience vs. what I've always heard about diesels:

4bt's do vibrate a lot, however I have the fluid-filled motor mounts & I can see clearly using my Stock CJ side mirrors. (You all know how crappy they are )

4bt's are loud. Yes. Isn't it awesome? Decent sound-deadening + new window and door seals help a lot but it is indeed noisy by any standards. Either you love it or not.

4bt's stink. My engine was in excellent condition and I rebuilt the injectors and resealed the inj. pump just because I'm anal that way. You really have to lean on mine to get it to smoke at all, and idling along on the trail there is no smoke and hardly any fumes. A poorly-tuned gas carb is much worse. If you go tuning on a diesel, you load a lot more fuel into the system that will not be burned = fumes/smoke.

4bt's are heavy. Yes indeed. Would not be ideal for muddy trails or off-camber stuff. Probably look at a 3.3L or something else if you had to have a diesel for that. If you have the $ and the technical know-how, the VW TDI swap would be ideal.

4bt's are slow. Tell that to all the commuters I cruise past each morning @ 75mph+
07-12-2013 01:05 PM
Rubicondon53
Quote:
Originally Posted by caryt View Post
Sorry I didn't know that if I didn't state my background that my opinion would be compared as you did. As to your metaphorical witticisms ...grow up.
So, I guess Mathew, Mark, Luke and John should also grow up? The Bible, as with all great literature is full of metaphorical witticisms... I suppose I should be quiet now.. You obviously just don't get it...
07-12-2013 12:27 PM
caryt Sorry I didn't know that if I didn't state my background that my opinion would be compared as you did. As to your metaphorical witticisms ...grow up.
07-11-2013 05:14 PM
Rubicondon53
Quote:
Originally Posted by caryt View Post

So now you are making comparisons..like this. Nice to know this is how you think.

Where have I said I had a bad experience. I have diesels and love them on the street. And have likely more experience with Diesels than you do as its my business. No diesel will be as stink free as a injected gas motor.

I don't want to get behind a carb'd gas motor either.

So get your diesel and likely spend 2x's the $ that having a LS would cost, not counting the added weight.
If, a big word, if you read all of this thread you would see that I recommended the Chevy LS ( 350)... Having clarified that, Diesel engines for personal vehicles have been getting a bad rap, the GM conversion diesel didn't help any.. ( late 70s/early 80s? ). I also asked a lot of practicality questions of the guy that made the 4bt swap, and as usual practicality questions were unanswered, mainly because the swap is basically a novelty, and not a good swap for very long range travel... My first major FFA project was rebuilding a J I Case model 600 Diesel engine ,,, ( in 1970 ) and have been around, worked on, and operated diesels ever since.. As far as how I think? You haven't a clue, as I often invoke metaphorical witticisms to make my point... If you have all that experience with diesels then why didn't you just say so, then I would not have justifiably come to the conclusion that your remark was based upon an antidotal experience.. Later on.
07-11-2013 09:23 AM
caryt
Quote:
Originally Posted by Rubicondon53 View Post
It's a shame you allow a single bad experience caused by a negligent driver to shape your overall opinion, I guess there is no convincing people that use antidotal evidence to formulate their personal world views.. I met a guy only last week. He was a bigoted racist from Mississippi. I guess all good ole boys from Mississippi are bigoted racists? I guess we should never allow facts to get in the way of opinion.. Banging head several times....

So now you are making comparisons..like this. Nice to know this is how you think.

Where have I said I had a bad experience. I have diesels and love them on the street. And have likely more experience with Diesels than you do as its my business. No diesel will be as stink free as a injected gas motor.

I don't want to get behind a carb'd gas motor either.

So get your diesel and likely spend 2x's the $ that having a LS would cost, not counting the added weight.
07-10-2013 03:00 PM
UnlimitedRubicon
Quote:
Originally Posted by Rubicondon53 View Post
I guess we should never allow facts to get in the way of opinion.

It seems to work for you.
07-10-2013 02:50 PM
jmcc75
Quote:
Originally Posted by Rubicondon53 View Post
He was a bigoted racist from Mississippi. I guess all good ole boys from Mississippi are bigoted racists?
I think that's pretty close to fact I was never proven otherwise last time I was there lol but to the op would you consider using the 4.5l QSB cummins? I've seen in swapped into a YJ but I think it'd be pretty sweet in a TJ
07-10-2013 02:17 PM
Rubicondon53
Quote:
Originally Posted by caryt View Post
Then you guys get stuck behind one...no diesel will smell as clean as a fuel injected small block..besides the OP was asking about a 4bt
It's a shame you allow a single bad experience caused by a negligent driver to shape your overall opinion, I guess there is no convincing people that use antidotal evidence to formulate their personal world views.. I met a guy only last week. He was a bigoted racist from Mississippi. I guess all good ole boys from Mississippi are bigoted racists? I guess we should never allow facts to get in the way of opinion.. Banging head several times....
07-10-2013 11:49 AM
brandon-99tj
Quote:
Originally Posted by NCJeepin View Post
Am I the only one in here that thinks diesel smells good??
Nope. I love the smell of diesel
07-10-2013 11:14 AM
Lando25
Quote:
Originally Posted by "caryt View Post
besides the OP was asking about a 4bt
Cummins 4bt is a diesel.
07-10-2013 10:14 AM
NCJeepin Am I the only one in here that thinks diesel smells good??
07-10-2013 09:41 AM
caryt Then you guys get stuck behind one...no diesel will smell as clean as a fuel injected small block..besides the OP was asking about a 4bt
07-09-2013 10:54 PM
Lando25
Quote:
Originally Posted by caryt View Post
Any fuel injected gas motor is better than a sticking diesel on a trail. I go to enjoy the outdoors not smell diesel fumes. Diesels are great on asphalt where they belong.
As others have said diesels overall are clean and very efficient. They have a bad stigma from 16 year olds chipping their dads truck so the injectors pour too much fuel causing it to smoke. The diesel in my 82 Monte Carlo is cleaner and far more efficient than anything that was offered back the. The same holds true today.
07-09-2013 10:26 PM
McDaniel274
Quote:
Originally Posted by Rubicondon53 View Post
I'm curious, as I stated before, the 4bt is the only diesel swap I would consider, how long ago did you do the swap? Did you retain the jeep transmission? And what gears are you running, 3:07s? If you have 3:07s you should be very comfortable cruising at 70 mph at around 1600 rpms. While cruising at highway speeds does it smooth out nicely? I've considered this swap instead of buying a new rubicon in the future but haven't found anyone willing to talk about how well it works for long range travel, ie, exploring North America, from the Rockies to the Yukon and on up into Alaska.... Retirement is around the corner and we plan on long range extended trips.. 24 mpg is a lot better than 12 to 14 mpg which is what we currently get with our 4.0, loaded with gear and pulling the trailer... The 4bt wouldn't even sneeze at the extra weight... . Nice job !!
"Simplicity is the key to longevity" - I want to trademark that quote haha but crazy luck is why I'm driving it today. I started out looking to buy TJ, one with low miles no lift, no abuse. My dream was to build what I drive today. I started out looking for build sheets other forums and "running" the numbers of what it would cost to build a Tj with a 4bt conversion. Some how I stumbled upon this jeep on a 4btswaps.com forum and the guy had a buildsheet of everything ever done to it. This was going to be my "blueprints of what I wanted to build". And by sheer luck I stumble upon this same jeep forsale. I jumped on the chance to purchase it I only have 12g for and 03 jeep with everything you see on it now and the owner was only a 100miles away from me. Like I said sheer luck haha

Now for the jeep 03 TJ 3.9l 4bt cummins turbo mechanical VE pump with gm clutch and bell housing transmission NV3550 and np231 and Dana 30-35 axles @ 3.07s the jeep I have nearly 20,000 on it since I've owned it I commute nearly 400-500 a week in it between school and work pumped is turned up with predator injectors was on the dyno at one point and put out 250hp and around 450ft/lb everything is mechanical, the Tj is as simple as simple gets, only break down has been front seal went out on pinion bearing on the rear axle. And theres no vacuum pump on the engine so you have to run a hydro-boost system for the brakes and you lose your vent controls. But a simple 12volt vacuum pump can easily fix that vent. Do i plan on building everything up i.e NV4550, atlas, dana 44's, etc. I will replace the old as they go. Does it smoke, yes, does it smell like diesel, yes, but do I care not one bit. Watching that boost gauge being pinned at 40lbs and rear tires chirping and leaving a subtle cloud behind doesn't happen everyday in jeep
07-09-2013 10:47 AM
SAABseanSCANIA
Quote:
Originally Posted by Rubicondon53 View Post
Sadly, you are mis-informed beyond reasonable belief.. A well tuned ( dyno-tuned ) diesel, even the older Diesel engines, do NOT smell of diesel. . New diesel technology are extraordinarily clean.. Bio diesel, smells a little like french fries, and emit 0 emissions..... If I ever make the swap, I'd be burning a lot of emission free veggie oil... Can't say that about a gasser
100% correct. I think he's seen too many kids with Powerstrokes blowing black smoke all over the place because they think turning their injection pumps up is "cool".

A proper running diesel is actually cleaner than a gasoline engine in theory. Noisier? Sometimes. Dirtier? Not necessarily. They are also more efficient and the fuel is less dangerous to transport than gasoline in the event of an accident; which is why ground force tactical vehicles aren't gasoline.........gas engines have a heck of a time burning JP-8
07-09-2013 10:46 AM
wrangler0232
I would say 4bt get the torque I was thinking that if I chose to go diesel or a 5.7 hemi
07-09-2013 10:45 AM
NJO 426 Hemi and don't look back.
07-09-2013 10:39 AM
Rubicondon53
Quote:
Originally Posted by SAABseanSCANIA View Post

Well, I have to chime in on a diesel topic....

I'd agree (formerly having to be cummins/CAT certified) that the old cummins would be the way to go for simplicity if you've been bitten by the diesel bug; and if you're buying a true mechanical B series engine. The great thing about these old engines is they're mechanical; the fuel system is a mechanically driven, mechanically timed, rotary vane pump or inline cam driven (translation: cheap rebuild). I get a giggle every time I hear a RAM guy say he has a 6BT in his 98+ 2500..... because it's not; it's electronically controlled Bosch as they all are (whether common rail or not). If you plan on getting an ISB (after 97), plan on dealing with unit injection. But with a mechanical engine in mind, you might have to adjust valve lash and you WILL (and I mean that) be rebuilding pumps; but it's cheaper to rebuild at intervals than replace at failure, that's why they're useable service life is about 350K before complete overhaul (500K is optimistic but possible) .

Don't get me wrong, the electronics aren't necessarily BAD; and I don't think the system is realistically "flawed" as almost every new vehicle with an internal combustion engine is HP common rail nowadays. The VM Motori you had in the liberty has a "modern" system in the sense that the unit injectors are controlled by a computer and the fuel delivery is under high pressure in a "common rail" (which your VW gasser is as well by the way). In your case, you had a Bosch CP3 Pump. Within this unit there are a couple components. It has a lift pump attached to the rear of the HP housing that draws the fuel to the HP Pump. What this does is supply fuel and keep the HP Pump lubricated (aka feed the pump). In between there is a regulating valve that controls pump lubrication, fuel supply to another valve, and acts to return fuel to the tank. On top of that, there is a fuel quantity valve that controls the amount of fuel heading into the HP pump (metering). Finally the HP side of the pump supplies rail pressure. Lot going on in there huh? But, the Bosch CP3 is used in all modern Cummins and Dmax engines, so "flawed" wouldn't be the word for a single point failure. With 93K miles I'm assuming that no fuel pressure high/low test was performed prior to the failure? I don't own a CRD so I'm not sure what the dealers do as far as service, but with a modern diesel it's either buy the equipment to do it yourself or cough up the money for a shop to do it. My guess is either the valving failed or the lift pump failed; both cause the HP pump to lean out and fail. But this is the technological world we live in with fuel economy and emissions to worry about. The benefit to having an electronically controlled system is controlling fuel volume, exhaust temps, engine speed, and emissions (all very important when trying to market a highway capable Jeep Liberty that gets "great" fuel economy). So an electrically controlled fuel system isn't necessarily "flawed" per se, but it's certainly not as simple as a mechanical system and with symbiotic components there's bound to be failures (VW diesels are unfortunately experiencing a bad rep for their fuel systems as well).

That's my .02 anyways. I'd love to run an old 4BT in mine for pure novelty but the cost outweighs the "joy" I personally would get from it. I also don't think weight is an issue because plenty of gents on here have done the swap and they're riding just fine, so I imagine they've mastered the issue.
Agreed,,, I learned about everything you wrote on the way there... It isn't necessarily the CP3's fault that it suffered from lack of lube... Chrysler went on the cheap utilizing too many components from a gasser unit,, ie, rubber fuel lines, weak connectors, bad filter head with hearing unit. etc,,, the biggest flaw was the lack of a lifter pump.. The dealership never succeeded in getting the fuel bubble free, which I discovered when installing a new filter at 40,000 miles... I have theorized that the constant flow of air bubbles, caused by small leaks, and the lack of a lifter pump, caused the early demise of the CP3... I'm over it now, but at the time I was very upset that Chrysler off handedly dismissed my logic and refused to help with the repair bill.. You are obviously much better versed on the subject, is theory wrong?
07-09-2013 10:06 AM
Rubicondon53
Quote:
Originally Posted by caryt View Post
Any fuel injected gas motor is better than a sticking diesel on a trail. I go to enjoy the outdoors not smell diesel fumes. Diesels are great on asphalt where they belong.
Sadly, you are mis-informed beyond reasonable belief.. A well tuned ( dyno-tuned ) diesel, even the older Diesel engines, do NOT smell of diesel. . New diesel technology are extraordinarily clean.. Bio diesel, smells a little like french fries, and emit 0 emissions..... If I ever make the swap, I'd be burning a lot of emission free veggie oil... Can't say that about a gasser
07-09-2013 09:54 AM
SAABseanSCANIA
Quote:
Originally Posted by Rubicondon53 View Post
LS all the way,,, if you insist on an oil burner, then the BT... The new diesels are seriously flawed... I had one of those Motori motors in a Liberty, at 93,000, catastrophic failure of the fuel delivery system, the Bosch high pressure pump went out, and took the entire fuel rail with it,,, $5,000 later we got it back on the road, sold it, and bought my wife a VW gasser... I'll never use a "modern" diesel ever again... The 4Bt, is simple old fashioned, tech, and extraordinarily dependable for at least a half million miles.... Just my 2 cent
Well, I have to chime in on a diesel topic....

I'd agree (formerly having to be cummins/CAT certified) that the old cummins would be the way to go for simplicity if you've been bitten by the diesel bug; and if you're buying a true mechanical B series engine. The great thing about these old engines is they're mechanical; the fuel system is a mechanically driven, mechanically timed, rotary vane pump or inline cam driven (translation: cheap rebuild). I get a giggle every time I hear a RAM guy say he has a 6BT in his 98+ 2500..... because it's not; it's electronically controlled Bosch as they all are (whether common rail or not). If you plan on getting an ISB (after 97), plan on dealing with unit injection. But with a mechanical engine in mind, you might have to adjust valve lash and you WILL (and I mean that) be rebuilding pumps; but it's cheaper to rebuild at intervals than replace at failure, that's why they're useable service life is about 350K before complete overhaul (500K is optimistic but possible) .

Don't get me wrong, the electronics aren't necessarily BAD; and I don't think the system is realistically "flawed" as almost every new vehicle with an internal combustion engine is HP common rail nowadays. The VM Motori you had in the liberty has a "modern" system in the sense that the unit injectors are controlled by a computer and the fuel delivery is under high pressure in a "common rail" (which your VW gasser is as well by the way). In your case, you had a Bosch CP3 Pump. Within this unit there are a couple components. It has a lift pump attached to the rear of the HP housing that draws the fuel to the HP Pump. What this does is supply fuel and keep the HP Pump lubricated (aka feed the pump). In between there is a regulating valve that controls pump lubrication, fuel supply to another valve, and acts to return fuel to the tank. On top of that, there is a fuel quantity valve that controls the amount of fuel heading into the HP pump (metering). Finally the HP side of the pump supplies rail pressure. Lot going on in there huh? But, the Bosch CP3 is used in all modern Cummins and Dmax engines, so "flawed" wouldn't be the word for a single point failure. With 93K miles I'm assuming that no fuel pressure high/low test was performed prior to the failure? I don't own a CRD so I'm not sure what the dealers do as far as service, but with a modern diesel it's either buy the equipment to do it yourself or cough up the money for a shop to do it. My guess is either the valving failed or the lift pump failed; both cause the HP pump to lean out and fail. But this is the technological world we live in with fuel economy and emissions to worry about. The benefit to having an electronically controlled system is controlling fuel volume, exhaust temps, engine speed, and emissions (all very important when trying to market a highway capable Jeep Liberty that gets "great" fuel economy). So an electrically controlled fuel system isn't necessarily "flawed" per se, but it's certainly not as simple as a mechanical system and with symbiotic components there's bound to be failures (VW diesels are unfortunately experiencing a bad rep for their fuel systems as well).

That's my .02 anyways. I'd love to run an old 4BT in mine for pure novelty but the cost outweighs the "joy" I personally would get from it. I also don't think weight is an issue because plenty of gents on here have done the swap and they're riding just fine, so I imagine they've mastered the issue.
07-09-2013 09:22 AM
caryt Any fuel injected gas motor is better than a sticking diesel on a trail. I go to enjoy the outdoors not smell diesel fumes. Diesels are great on asphalt where they belong.
07-09-2013 06:03 AM
Rubicondon53 I'm curious, as I stated before, the 4bt is the only diesel swap I would consider, how long ago did you do the swap? Did you retain the jeep transmission? And what gears are you running, 3:07s? If you have 3:07s you should be very comfortable cruising at 70 mph at around 1600 rpms. While cruising at highway speeds does it smooth out nicely? I've considered this swap instead of buying a new rubicon in the future but haven't found anyone willing to talk about how well it works for long range travel, ie, exploring North America, from the Rockies to the Yukon and on up into Alaska.... Retirement is around the corner and we plan on long range extended trips.. 24 mpg is a lot better than 12 to 14 mpg which is what we currently get with our 4.0, loaded with gear and pulling the trailer... The 4bt wouldn't even sneeze at the extra weight... . Nice job !!
07-08-2013 10:44 PM
NCJeepin
Quote:
Originally Posted by McDaniel274 View Post
And it looks like it belongs in there as well haha
Man that's clean. Looks great. Definitely go 4bt. Perfect for offroad with gobs of torque (you don't need the high rpm horsepower offroad). Plus you will have plenty of power on road with good, well better mpgs. Not to mention the reliability of the Cummins. I plan to do the 4bt swap in the future after school.
07-08-2013 10:11 PM
jmcc75 That's sexy
07-08-2013 07:19 PM
McDaniel274 And it looks like it belongs in there as well haha
07-08-2013 07:12 PM
McDaniel274 I currently run a 4bt in my 03 Tj it's been very practical for me so far 24mpg w/ 4in lift on 33's and its my daily driver but weight wise the difference between a LS1 and 4bt is around 250lb and I have a heavy front bumper and winch on the front and the coils and shocks aren't any different holds up no problem even under interstate speeds and its a cummins they run forever
07-08-2013 06:46 PM
HillbillyJeeper If you go diesel your gonna have to think front springs and shoks too, might be OK overtime, and if you aint off road much. but hard wheelin that extra weight might be a factor. I'm still a diesel fan tho.
07-08-2013 06:40 PM
Bravo.Justin Yup, knew I wasn't that crazy yet
07-08-2013 06:36 PM
Bravo.Justin
Quote:
Originally Posted by MississippiDirtTJ View Post

I can't find anything pertaining to this on google. Care to share a link for to help enlighten the rest of us?
I read it yesterday in 4 Wheel Drive magazine. It's a 3.0L 182ci V6 if I remember correctly. Same mill as the Grand Cherokee. Let me find the article...
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