Street Trucks. Handling, braking, etc..

[87manche]

so, I'm on the throne last night.

I was reading through a recent issue of JP.

They showcased the currie parts MJ.

 

They had a very ingenious way of mounting a rear swaybard, welded it to the shackle mounts and came forward with the arms/links to the axle.

 

Something that you may want to try and find pictures of.

[Eagle]

And 2400 is right where I like to be for 70-75 mph, not 50.

My tire/gear charts don't get into any low-profile sizes. The smallest tire I worked up figures for is a stock 215/75R15. Assuming the 3550 has an overdrive ratio of 0.75:1 (I'm too lazy to check), here's what I get:

 

At 50 MPH, 4th gear (1:1) would be 2224 RPM and 5th would be 1668 RPM running stock 3.54 gears.

 

Same gears at 70 MPH ==> 3114 RPM & 2336 RPM

-------------------------------

Jump to 4.10 gears

 

At 50 MPH, 4th gear would be 2576 RPM and 5th would be 1932 RPM

 

Same gears at 70 MPH ==> 3607 RPM & 2705 RPM

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Jump to 4.56 gears

 

At 50 MPH, 4th gear would be 2865 RPM and 5th would be 2149 RPM

 

Same gears at 70 MPH ==> 4011 RPM & 3008 RPM

--------------------------------

Those tires are rated to turn 754 revolutions per mile. You can get the tevs per mile for any other tire size you're considering and just do the math to convert those RPMs to the different tire size. It's a direct proportion.

[DirtyComanche]

so, I'm on the throne last night.

I was reading through a recent issue of JP.

They showcased the currie parts MJ.

 

They had a very ingenious way of mounting a rear swaybard, welded it to the shackle mounts and came forward with the arms/links to the axle.

 

Something that you may want to try and find pictures of.

 

Saw it in the rag. Bling parts. It's an option if I kept the leafs.

[cherokee]

Are there any dual piston calipers that bolt in place of the standard d30 caliper?

 

I think one of the kits earlier in this thread had them, but it was both pricy and required modification.

[FxRacing282]

TNT from my years at the dragstrip i would have to go against you in the AWD department. a locked D44 with street drags radials would be much better then awd. once you get to the point where the truck no longer makes enough torque to spin the tires awd slows you down. and you can get to 30 or 40 real quick.

 

DirtyManche... a 350 or 351 with a 3 speed auto or a 4 speed and propper gears would make your truck about as fast as it can go. the few pounds from loosing the locks and windows is only a little little bit of time taken off. i would look into doing a winter project with that. I'm not sure where you are but my friend may be able to sell you a 305 for cheap. (I'm in new hampshire) or maybe a whole 350 with a 3hree speed. obviously this would be a on a 2wd as street rod trucks are 2wd

[Pete M]

The 5.0 from a mustang cobra would make for a sweet speedster. :D

[TNT]

TNT from my years at the dragstrip i would have to go against you in the AWD department. a locked D44 with street drags radials would be much better then awd. once you get to the point where the truck no longer makes enough torque to spin the tires awd slows you down. and you can get to 30 or 40 real quick.

 

This is true but in the rain on the street I would smoke almost anything up to 70mph and then they would have to catch back up after that. Besides that AWD rocks in turns.

[FxRacing282]

yeah its true but not until 70 mph. and it has the same possibility of rolling at high speed whether its awd or 2wd. personally i would take a long box 2wd dropped about 3-4 inches and built from the ground up like show quality and can run in quick street class (less then 10 seconds)

[JOMJ87]

Some kinda IFS from a FWD or AWD that wis strong would be really nice. If it was me I would go rotary engine with all the goodies and then throw what i could to make it a curd hugger. I am facinated abotu rotaries and i think they are great choices for preformance in a light package. I also like a diesel (4Blt cummins) with added goodies for the torque aspect. These are my dream engines for my rig but i think for a street runner they would make a nice sleeper. I would also run a SWB for a better turning radius and have the COG as low as i could with a air ride suspension that i could tune to get it perfect. The AWD idea i love after driving my cousins Suby around. it seems to have the best of both. The launch of rear and the control thru turns of a front without spiining tires. once the start sqealling they arent taking you down the road. The more torqu the happier i am though but these are crazy ideas i have had that i thought i would share. MAybe they are crazy talk but maybe one day....

 

Cole

[FxRacing282]

its interesting you say that cause i also love rotary engine as they make more HP and TQ per liter than a conventional internal combustion engine. diesels are sweet too but usually need a turbo charger and whatnot plusyou gotta plug em in during the cold months. a cummins with a chip and properly built and tuned would be wicked cool to see though

[DirtyComanche]

A 4BT would be an amusing engine, but not in any street truck. It would be like my dodge (6BT) but in a smaller package. It drive pretty good, but nothing like what I'd want to build in a MJ.

 

For a utility truck, a 4BT would be a great choice.

 

 

And the wankels... Not for me.

[DirtyComanche]

Some kinda IFS from a FWD or AWD that wis strong would be really nice.

Cole

 

 

Yes, but there's not many good options. Most stuff offered from the factory is either not up to the task, not easily adaptable to anything else, or just plain stupid. The AMC eagle stuff is interesting because it's a D30 centre section with unit bearing outers, much like a solid D30. At least, that's AFAIK. It would be interesting...

 

 

But those SCCA trucks raced with a solid front, so I'm sure it's possible.

[akamcbird]

the eagle axle would be good but hard to adapt the ifs control arms, the upper a arm is mounted to the sheet of the inner fender w/coil and shock mounted on top of the a arm and again mounted at the top to sheet.

 

use your imagination since everything is gone

[DirtyComanche]

That might be a PITA. However, a guy can build his own A-Arms.

 

 

This FJ has IFS:

 

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And it didn't come off another vehicle! Well, sorta, gamma goat centre section (magnesium, ooooo) and some D60 parts, but it's pretty much custom.

 

It could be built, but is it worth it?

[feerocknok]

After comparing my AWD Audi to my RWD RX-7, I wouldn't be going back to rear wheel drive for the twisties. The AWD slides sideways just as easy with e-lockers as the RWD does with an LSD, but I can cut out of the slide immediatly in the Audi.

 

Solid axles are not good in corners!!!

[FxRacing282]

if you got the time and the tools to do it do coils out back and ifs up front. I'm sure a ranger ifs system wouldnt be too bad

[Indy_MJ]

In a street truck I would start with a SWB MJ and add the following:

 

285/40ZR18 BFG KDW tires

18x10" forged alumium rims

 

Has anyone put that wide of a tire on a lowered jeep? I know you can get the right offset wheels and/or wheel spacers so that they don't rub, but I would be nervous that it would in the front at full lock.

[Hawk]

The glass fenders are also negligible in weight difference. I couldn't tell between my baja's and my stock fenders, so after purchase price, and painting, they're not worth it as far as weight. Wheel travel, on the other hand....perfect.

[feerocknok]

In a street truck I would start with a SWB MJ and add the following:

 

285/40ZR18 BFG KDW tires

18x10" forged alumium rims

 

Has anyone put that wide of a tire on a lowered jeep? I know you can get the right offset wheels and/or wheel spacers so that they don't rub, but I would be nervous that it would in the front at full lock.

They measure out to 11.2" wide. Not too bad for rubbing, but it would hit.

[TNT]

In a street truck I would start with a SWB MJ and add the following:

 

285/40ZR18 BFG KDW tires

18x10" forged alumium rims

 

Has anyone put that wide of a tire on a lowered jeep? I know you can get the right offset wheels and/or wheel spacers so that they don't rub, but I would be nervous that it would in the front at full lock.

They measure out to 11.2" wide. Not too bad for rubbing, but it would hit.

 

They are 27" tall which would fit. I can fully bottom a 31x10.5-15 without springs in and turn from lock to lock with only light LCA contact. The shorter tire wouldn't hit on the right rims.

 

A better combo would be 4.10 frt gears with 275/35ZR19 tires and 4.88 rear gears with 305/40ZR22 tires. This would have a top speed of 130mph with 2500rpm at 65mph. That would be a 26.5"x10.9" front tire and a 31.5"x12.4" rear tire. The front should clear without rubbing. I wouldn't lower it more then 1" in the front when compared to a 2wd ride height and about 2"-3" in the rear so it sits level.

 

Now that would be wicked

[DirtyComanche]

The glass fenders are also negligible in weight difference. I couldn't tell between my baja's and my stock fenders, so after purchase price, and painting, they're not worth it as far as weight. Wheel travel, on the other hand....perfect.

 

 

 

I'm thinking they'll be worth it for the $40 worth of glass... I think I can mold a stock fender and reproduce it - but instead of using chopped mat that's absurdly thick I'd do it the 'right' way. Same goes for the hood. I hate buying stuff that I can make.

[Hawk]

That's cool. I gave a kid a set of revolver shackles for my baja's, so all I had to do was put the holes in the right spot for install, then get them painted.

 

(I even had the underside primed, you know, so they don't rust...)

[DirtyComanche]

Rust is always an issue! :roll:

 

 

 

I've been doing some more reading (never good) and hence have been looking into some more radical things. IRS is one. Amusingly enough, a guy can buy a setup off the shelf (anybody read street rodder?) but they are all so poorly designed that I'm thinking the gene pool needs some chlorine.

[Hawk]

You could probably have a fab shop build a 4-link with coil-overs back there and keep the solid axle, tub the bed a little and stick some nice wide street slicks in there....that's about as crazy as I'd get with mine. I'm leaving leaf on it for a while though.

[DirtyComanche]

The problem with attempting to tub one of these trucks is the frame in the rear is too wide. If a guy wishes to run a tire that is too wide for the wheel wells, he might as well look at cutting the whole frame off the back half and building a new one out of tube. I've thought about that. It's a matter of where I'd want to draw the line.

 

 

4-links are easy. But for anything but drag racing and rock crawling, a solid rear end isn't ideal. Too much unsprung weight. And camber doesn't change in an ideal way. Same with a solid front end. Hence the whole IFS thing... I'm still doing more reading into the workings of independant suspensions, but I now know enough to not be afraid of them.

 

Somewhat unrelated, I also read a really good book on materials and realized how many bad things I've done in the past. And better yet, how many bad things most of the 4wd suppliers do.