What Breaks In A Boosted 4.0L?

[carnuck]

Don't do 5th wheel if you plan on ANY rough terrain! Go gooseneck instead.

[89Patches]

This is the blown 4.0.

 

https://www.facebook.com/photo.php?v=10151956418415991&set=vb.747280990&type=2&theater

The link didn't work for me.

 

The stopping power of the four pistons is going to be nice and all but I would think of the rest of the stress placed on all the other components in the front end.  I can't help but think of the four link and not sure I ever seen such load applied with that kind of front end.  all the tow rigs ive seen (real tow rigs) are leaf sprung or independent, I'm thinking its for a reason I can only imagine the stress put on the trackbar and the links stopping a load of that size time and time again.  I get what your trying to do, but if your serious about making a manche a serious tow rig ditch all the ideas of large improvements in small areas and look at it from a larger safer scale.  If I were to do it and I am purely speculating here with an unlimited budget of coarse.   First full size axles and all the goodies that come with it, leaf spring front end, major frame stiffening add ons, air bags in rear, hydro brakes, high sprung (heavy) suspension all around for sure, tightened up trans with major aftermarket coolers and built to the hilt long block(w/major rod journal oiling mods) boosted just enough to tow my shyte...putting a cooling system in that is still up in the air if you don't want to mount something extra in the bed with aux fans.   It sounds like you know the ins and outs of performance parts but they don't have a kit to make the mj into a pulling power house.  think of it like this   Its been done before many many times and who knows maybe they started out with something even less substantial than a compact truck but the end result is sitting next to you at the stoplight. A fullsize truck overbuilt not for the soccer mom but intended for towing a fellow auto behind it with no foreseen issues. Just try to think of everything you need to make it happen not what you can get away with is all.  Edge of your seat is for racers its why they get to have all the fun. towing in a real life situation is not a sport, its a responsibility to everyone around you. When I tow and I tow a lot I never worry about my rig, I worry about everything else around me and what to do if they make me nervous..  I mean no offence but build the baddest tow manche we have seen yet that would be @#$%in sweet.

By "Real tow rig" you are talking about diesel truck? The reason why there suspension is way more "beefed" up is because they have a fully dressed 2000lbs motor that sits in the front.

 

From what I read I am under the impression that you think i'll be towing 10,000+ lbs :doh:  The most I would probably ever tow would be 5000 lbs MAX!! which really isn't a lot of weight.

And I would like to daily the truck as well with out having stupid stiff suspension...

 

5th wheel on a long bed Metric Ton package maybe? Longer wheelbase would make for a more stable towing platform, and the 5th wheel  hitch would distribute  load weight better. 

My truck is a LWB :thumbsup:  I like having a usable bed ;)

[mvusse]

 

This is the blown 4.0.

 

https://www.facebook.com/photo.php?v=10151956418415991&set=vb.747280990&type=2&theater

The link didn't work for me.

 

Must be privacy settings. It's not my video.

[zagscrawler]

No I was not just referring to a diesel only. there are plenty of gas tow trucks out there as well and they share the same platform as the diesel versions but with like you said a bit more up front for the heavy engine. Its the platform that worries me is all. I am not an expert on how strong the stock chassis is really but when I converted mine to 4wd I stuck some 35's on it and of coarse had major deathwobble troubles.  I read and talked to many different folks on what causes and cures it of coarse and they all had different reasons and fixes.  Most of the fixes were bandades in my opinion so I looked at how the road forces were being applied to the chassis and came to realize that all the important pickup points were on the driver side only.  Fine I'm sure if you are trying to control things in stock form but needed to be strengthened for the large rubber it was trying to keep in check. All I did was build two frame connecters up front and boom no more dw's,  The driver side of my chassis was flexing and I would have never guessed it. I didn't change anything else, hell my stearing stabilizer shock is the original and completely useless.  This is why I think the chassis was just not built to handle full size duties from the get go.  I think it can be made into a much more sturdy platform with a little care. I wish you the best of luck and I will fallow the build for sure. The turbo motor is just to bad @$$ to not check out.  I know I am coming of as a downer so ill keep my negatives to my self from now on and want to wish you the best of luck with your truck. 

[89Patches]

No I was not just referring to a diesel only. there are plenty of gas tow trucks out there as well and they share the same platform as the diesel versions but with like you said a bit more up front for the heavy engine. Its the platform that worries me is all. I am not an expert on how strong the stock chassis is really but when I converted mine to 4wd I stuck some 35's on it and of coarse had major deathwobble troubles.  I read and talked to many different folks on what causes and cures it of coarse and they all had different reasons and fixes.  Most of the fixes were bandades in my opinion so I looked at how the road forces were being applied to the chassis and came to realize that all the important pickup points were on the driver side only.  Fine I'm sure if you are trying to control things in stock form but needed to be strengthened for the large rubber it was trying to keep in check. All I did was build two frame connecters up front and boom no more dw's,  The driver side of my chassis was flexing and I would have never guessed it. I didn't change anything else, hell my stearing stabilizer shock is the original and completely useless.  This is why I think the chassis was just not built to handle full size duties from the get go.  I think it can be made into a much more sturdy platform with a little care. I wish you the best of luck and I will fallow the build for sure. The turbo motor is just to bad @$$ to not check out.  I know I am coming of as a downer so ill keep my negatives to my self from now on and want to wish you the best of luck with your truck. 

I see what your saying. But I believe what your talking about applies to lifted truck with like you said 35" tires, The forces are much different when towing so I don't think It will have a large impact like your saying, with only a 3" lift and 31's. But I would like to eventually up grade the front suspension, But as of right now I don't think it's necessary just yet. But I do hear what your saying!!

I have to finish the engine build on my car this winter and also get the MJ painted, So I will be drained to start the engine build on the MJ. but I would like to get all the "supporting mods" and suspension mods done before I tear in to the motor. I hope you stay tuned in when the build starts :thumbsup:

 

And finally does anyone know what a Metric Ton is rated to tow from factory?

[reece146]

We are talking about a truck that was designed to tow 5000 lbs from the factory.

 

Upgrades are to make it perform closer to current expectations. Not increase tow rating (you can't - you need to redo the type certification to do that).

 

What you can buy in the show room today is nuts. Don't the modern trucks do 0-60 in under 8 seconds with 10,000k lbs in tow? I may be exagerating but you get my point.

 

Build it well, be smart about it...

 

Not to keep harping... I tow a ~3500 trailer. My Jeep (XJ) is fully built and weighs ~4200 lbs empty... Empty! Add two adults and two kids, a weeks worth of camping equipment and bikes, etc...

 

Juggling the weight around that is like towing a 4500+ lb trailer with a stockish MJ. Without trailer brakes it tows adequately but I have larger than stock brakes on the Jeep. It's no hot rod on an incline but it gets by ok. On level ground it is fine.  It needs trailer brakes.

 

To be certain the load isn't pushing around the truck in a panic situation add trailer brakes, anti-sway and a weight distributing hitch. You'll be fine. 

 

2¢

[johnj92131]

When properly equiped, the max tow rating for the MJ is 5000 lbs.  Properly equipped means a weight distributing hitch, metric ton/big ton package, automatic transmission, power breakes and steering, heavy duty trans mission cooler, hd radiator, etc.  Please note, a standard transmission is not part of the package.  Also note that the truck must be a long bed to have the factory big ton/metric ton package.  There you have it.  What the factory says you need to tow 5000 lbs.

 

 

And finally does anyone know what a Metric Ton is rated to tow from factory?

[89Patches]

So basically from what you guy's said, My truck as it sits could tow 5000 lbs. Because I guess you could  say I added a "metric ton" package when doing the 97+ swap.

 

So I may as well go over the current mods that are done to the truck.

 

-  97+ interior swap

-  00' 4.0L H.O

-  AW4 w/ Big trans cooler

-  Ford 8.8 3.73 LSD

-  Dana 30 HP 3.73

-  Retained Rear 8.8 rear sway bar

-  WJ front sway bar

-  "Metric Ton" rear leafs 

-  3" lift kit 

-  Braided SS brake lines/ DD brake booster

 

I am probably leaving some stuff off, It's been awhile.

And just throw up a Pic of how it sit's at the moment.

 

Image Not Found

 

And I do realize that there will be problems with the certification, But that's a problem for later. 

[Tactical Bacon]

All you're missing from that list is a Class 3 Receiver Hitch to be able to tow 5k.

[zagscrawler]

The 5000 pound mark seems very realistic at this point but I guess I was pondering to much on the 400 hp and boosted upgrade which puts the towing range (power wise) a bit more than that i would imagine.  I guess you would just have power to spare on the uphills with that kind of power.  The way the thread started threw me off i guess considering the truck can tow what you want right now..

[Pseudosport]

We've been running a boosted 4.0L for a few years now but we are only making 200 whp / 260 wtq at 7 psi from a 50 trim T3/T4. Nothing crazy but its still going strong at this power level. From what I've read the pistons, rod bolts, and engine management are the weak links. Haven't seen anyone bending rods yet.

[reece146]

You are running MS (v2?), right?

 

How big a deal would it be to get MS running on a normally aspirated 4.x?

[gogmorgo]

We've been running a boosted 4.0L for a few years now but we are only making 200 whp / 260 wtq at 7 psi from a 50 trim T3/T4. Nothing crazy but its still going strong at this power level. From what I've read the pistons, rod bolts, and engine management are the weak links. Haven't seen anyone bending rods yet.

wtf is wtq? lb-ft?

[HOrnbrod]

Wheel torque I would imagine. 

[Pseudosport]

We're running MS1 v3.0 on the 1995 turbo Cheorkee and I've also wired one up on a 4.7L stoker in a Comanche with a 1991 harness swap. Install was the same. Tricky part was finding a Ford 6 vane shutter wheel to bolt into a 91-93 distributor.

 

wtq = wheel torque.  Sorry for any confusion, might have just made up that abbreviation.

[HOrnbrod]

wtq = wheel torque.  Sorry for any confusion, might have just made up that abbreviation.

 

Hesco and other stroker engine builders use this abbreviation. Probably the most important number you look at on the dyno.

[gogmorgo]

:soap box:

I knew wtq was wheel torque. My point however was that you should always include units with your torque numbers. Just using wtq and quoting a number could mean anything. Yeah, in North America you can generally assume the person is referring to lb-ft and in most cases be correct, but without units, you just have a meaningless number.

 

It's like saying something has a length of "11". 11 whats? Feet? Inches? Meters? Millimeters? Nanometers? Gigameters? Cubits? Stories? Furlongs? Leagues? Chains? Ångströms? Nails? Barleycorns? Fermi? Parsecs? Poppyseeds? Light-years? Hell, Beard-Seconds??? :headpop:

See? MEANINGLESS NUMBER!!!

 

 

The two most used units of torque, pound-feet (lb-ft) and newton-meters (nm) aren't all that close to each other (something like 0.7:1) and I've seen people refer to either as simply "tq" or worse, "torques".

I've even seen the same source, in the same context, quoting engine manufacturer outputs willy-nilly, ignoring the fact that they weren't all in the same units and referring to them simply as "torques" and then COMPARING THE TWO AS IF THEY WERE EQUIVALENT!!!! :mad:  :thwak:

 

 

 

 

 

Sorry... pet peave of mine.  :oops:

[HOrnbrod]

Of course you are correct, but have you ever seen a engine dyno runout that torque wasn't measured in ft/lbs? I haven't. This is a case in which it's very safe to ASSume ft/lbs due to the subject matter and number posted. Unless torque is commonly measured using different units in Canada. I don't know if it is.   :cheers:

[reece146]

Pedantic cat says you're pedantic.

 

The unit is "Torks"

 

I thought everyone knew that.

[Oyaji]

Of course you are correct, but have you ever seen a engine dyno runout that torque wasn't measured in ft/lbs? I haven't. This is a case in which it's very safe to ASSume ft/lbs due to the subject matter and number posted. Unless torque is commonly measured using different units it's different in Canada. I don't know if it is.   :cheers:

.

That would be because you are American - the rest of the world's  6.8 billion people use newton-meters (not pound-feet). Even professionals in the US use newton-meters, but for convenience of old farts like us who are too stubborn to change they  convert  figures to pound-feet.

.

Gogmorgo is right - precision and clarity do matter (I am sure his professors have drummed that into his head in his studies). That said, in the context it was presented (after adding 7 psi of boost) only pound-feet made sense to "ASSume" as  the correct unit.

[carnuck]

You mean like net HP vs Gross HP? Pre 1972 auto manufacturers used Gross HP ratings then insurance companies started hemming and hawing at 400 HP motors and jacking rates through the roof, so they started rating them net, with all accessories functioning in '72. That's why people think the smog stuff killed the HP because the numbers dropped so much. The reality is the power didn't get smogged away till a few years later when catalytic converters became required.

 

 

 

:soap box:

I knew wtq was wheel torque. My point however was that you should always include units with your torque numbers. Just using wtq and quoting a number could mean anything. Yeah, in North America you can generally assume the person is referring to lb-ft and in most cases be correct, but without units, you just have a meaningless number.

 

It's like saying something has a length of "11". 11 whats? Feet? Inches? Meters? Millimeters? Nanometers? Gigameters? Cubits? Stories? Furlongs? Leagues? Chains? Ångströms? Nails? Barleycorns? Fermi? Parsecs? Poppyseeds? Light-years? Hell, Beard-Seconds??? :headpop:

See? MEANINGLESS NUMBER!!!

 

 

The two most used units of torque, pound-feet (lb-ft) and newton-meters (nm) aren't all that close to each other (something like 0.7:1) and I've seen people refer to either as simply "tq" or worse, "torques".

I've even seen the same source, in the same context, quoting engine manufacturer outputs willy-nilly, ignoring the fact that they weren't all in the same units and referring to them simply as "torques" and then COMPARING THE TWO AS IF THEY WERE EQUIVALENT!!!! :mad:  :thwak:

 

 

 

 

 

Sorry... pet peave of mine.  :oops:

 

[carnuck]

PS: What usually breaks is the engine owner's wallet!

[Pseudosport]

The torque was rated in pound-feet (lb-ft) :thumbsup:

[gogmorgo]

I'm a little embarrassed about how emotional I get about that...

 

 

Of course you are correct, but have you ever seen a engine dyno runout that torque wasn't measured in ft/lbs? I haven't. This is a case in which it's very safe to ASSume ft/lbs due to the subject matter and number posted. Unless torque is commonly measured using different units it's different in Canada. I don't know if it is. 

 

Gogmorgo is right - precision and clarity do matter (I am sure his professors have drummed that into his head in his studies). That said, in the context it was presented (after adding 7 psi of boost) only pound-feet made sense to "ASSume" as  the correct unit.

 

The only dyno I have experience with is the ancient (soon to be replaced) engine dyno we use in our shop, which reads in KW and Nm. I don't remember the make off the top of my head, but I'm thinking it's an American brand.

But that said, I was reading through the reports and logs from the experiments with forced induction that the team did five years ago, and boost was always recorded in psi, right next to all the metric data.  :dunno:  To be honest, it's almost never safe to assume either system is going to be used in Canada. 

[reece146]

I have yet to see an automotive dyno in Canada read in metric. No one thinks in metric for automotive stuff, IME. Well, except that guy down in Sales that thinks he's a car guy because he has a car magazine subscription and drives a BMW. You know the guy, the one that is mostly always wrong about car stuff and you end up rolling your eyes at but can't be bothered to correct.

 

I've seen dynos with metric readouts in Canada but they were all industrial application equipment (gas turbines moslty).

 

Canada is kind of a hybridized I guess. Most think in kms and km/h but then most think in MPG (both Imperial and US to compare notes to the south and with the U.K.). I've noticed that most people under ~30-35 years old or so are starting to talk in l/100km more and more but that is a screwed up unit so I generally don't use it. You can't directly compare with the rest of the mostly commonly available English speaking automotive media out there.

 

Maybe it's just my circle of car peeps. One friend writes for a Canadian car mag and he is all metric all the time about cars except when we are talking about our race cars.  Then it's SAE for the engine and metric for the speeds and distance.

 

IIRC the U.K. is metric but their road signs are in mi/h and they talk in hp and lb-ft. Since they invented the foot, mile, gallon, etc. (i.e. the Imperial or British Gravitational system) I guess that makes sense culturally. The rest of Europe is all metric all the time. Same for Australia.

 

2¢