SOA too high; is it possible to flip leafs to lower some? (1 Viewer)

[TLCA_Paul]

nd get longer bolts that use all the nuts thread. The ones in the picture don't go into the nylon on the nuts. They need to go past the nylon so they don't back out. That would be bad.

on leaf springs I think you understand. so let me confuse you

4 leaf pack, even flex
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take out the bottom lef it stays even flex, if you take out one of the other leavs it puts stress on the upper leaf.

flex would stress V here first.
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Another thing to keep the springs soft is to make sure your clamps are loose that wrap the leaves.

 

[Niner]

(I own a minitruck that's an obstacle racer...my buddies stole it, caged it, gutted the front axle, dropped in a 400 SBC and an auto, custom shafted it, raced it, and rolled it 5 times....not sure I want it back or not.....)

It took them about 1 1/2 days to do that, he sure is slowing in his old age

 

[rem_7mmSTW]

nd get longer bolts that use all the nuts thread. The ones in the picture don't go into the nylon on the nuts. They need to go past the nylon so they don't back out. That would be bad.

on leaf springs I think you understand. so let me confuse you

4 leaf pack, even flex
_______________________
___________________
_______________
___________

take out the bottom lef it stays even flex, if you take out one of the other leavs it puts stress on the upper leaf.

flex would stress V here first.
___________________
_____________
__________

Another thing to keep the springs soft is to make sure your clamps are loose that wrap the leaves.

Well, you're right Chris, I'm confused (but have been that way for quite some time now)!
I took out the first two lower (shortest). Soft now, and lowered ride hieght by almost 2 inches. But probably won't work or end up bending the longer ones???
The bolt in the picture is not the correct one, and hasen't been tightened down. I'm aware of a few other odds and ends. I need to spend a few hours going over/correcting my punch list before cranking.

 

[Mace]

Rem you are fine with removing the bottom 2 leaves.

Add some gussetts to your link mounts. Even though you really are not using them for anything having a strong link mount is VERY important. Ask me how I know.

I still can't see any "floating" in that setup. I would imagine that the rear will quickly bind with the links and the leaves

 

[cruiserrg]

I still can't see any "floating" in that setup. I would imagine that the rear will quickly bind with the links and the leaves

The floating is in the fact that the leafs don't attach to the axle with u-bolts, but a "channel" for the leaf to pass through....you can see that in the rear axle pic. This is very typical for drag racing 4-link setups with leaf springs.

Rem,
One comment I will make is that the lower link attachments at the axle look to above axle centerline with no adjustment in the brakets. Most 4-link drag setups have the lowers below the axle centerline (way below in some cases) to keep the rotational forces of the "hooking up" under control. Also with no lower link adjustment and by the looks of the Instant Center of the links you may not get the desired launch characteristics, or be able to adjust them in.

You said street-strip...but looks like you are going more for strip. I would redo the lower link mounts and have them below the axles centerline and have some adjustment. Brace the upper frame link brakets as suggested, and also box them all and put a angle brace in front of the lower link frame mounts to spread out the shear forces on those brakets.

Lastly, if serious about dialing them in get a good set of racing coilovers and ditch the leafs, your weight transfer at launch will be much smoother and allow for tuning.

 

[rem_7mmSTW]

Thanks for the response Mace, I'll try it out as such.

 

[rem_7mmSTW]

Reuben,
You are exactly correct in your observation and assessment. The kit I had originally ordered from Comp. Eng. was set-up exactly as you have described with lowers lower than center point of axle housing. But this wasen't practical for a 4x4 that will occassionally be offroading. The drag links were really low. So, I decided to sacrafice / chop up the kit, and design my own while using what I could from the kit. That's when I found this site, along with Pirate 4x4, and was inspired by the custom designs. So, I kinda went out and did the same. I'm going to try it out and see how it performs before modifying too much.
I have to admit, that I can adjust the system fairly well merely by tuning the links. As a matter of fact, that's how I dialed in my pinion pitch for spec of driveshaft build.

thanks for all of the input,

regards,

 

[HI^C]

damn couple a days i am not on here, and i almost missed this!

few things lookin at the pics.

how much lower would you be happy with?

You state " launch control and spring wrap", you currently do not have enough seperation vertically with these current axle mounts.

reason for the load handler shocks? i can see if you need to stiffy the rear but it will lead to alot of height.


few comments, pulling leaves can affect spring rate while lowering height, the springs will settle a good amount ( mine about 1.5"). Please tell me there is rubber mounts on the transfercase torque mount?

captured coil using those race car things are something i like. ( cannot think of what they are called )

Break it IN, then decide on height.

 

[rem_7mmSTW]

3" would be nice. Achieved almost 2 by removing the two leafs.

then I guess I shouldn't tell you... (rubber mounts under adapter from tranny to NP205, teflon tranny mount, and that's about it for torque flex). Solid motor mounts, solid NP205 torque mount. Think I'll scatter pieces?

 

[Toyoland66]

Don't take this the wrong way.....

I would completely redo that 4 link, the way you have it set up it is bound to fail.

You need to move your lower link mounts down to the front of the axle housing instead of on top, the way it is set up right now it wont be able to control axlewrap without breaking, the leverage will be huge because there is hardly any verticle seperation.

I would also recommend moving the link brackets up at the frame side, at least the lower link brackets, the way they are right now there is a lot of leverage against the frame, and they hang pretty low for off-road

With that floating leaf setup all the torque is going to be transferred to the links, and with all that power they had better be strong

You have a lot of sweet mechanical stuff, and really clean fab work, but your design is lacking, I would recommend you do some researching here and on pirate4x4 and look at some designs that are proven to work

I'm not trying to be a ass or anything, I just dont think it would be safe the way you have it right now.

 

[wngrog]

Offer to race Nolen for pink slips, my daughter smoked him with a 2 bbl Cruiser once.
Butch

 

[cruiserrg]

Reuben,
You are exactly correct in your observation and assessment. The kit I had originally ordered from Comp. Eng. was set-up exactly as you have described with lowers lower than center point of axle housing. But this wasen't practical for a 4x4 that will occassionally be offroading. The drag links were really low. So, I decided to sacrafice / chop up the kit, and design my own while using what I could from the kit. That's when I found this site, along with Pirate 4x4, and was inspired by the custom designs. So, I kinda went out and did the same. I'm going to try it out and see how it performs before modifying too much.
I have to admit, that I can adjust the system fairly well merely by tuning the links. As a matter of fact, that's how I dialed in my pinion pitch for spec of driveshaft build.

thanks for all of the input,

regards,

No problem on the input. This is the first I have read about this seeing any off-road. I guess when you started saying no rocks no mud, I assumed that meant no off-road.

The traction from the 4-link will work well on the strip as well as off-road, but the mounting of link systems inherantly don't do either well, usually like your design they will work well in one sitch (drag racing in your case), but be horrible rock and log catchers off-road. Your trasfercase mount gave me the impression this would never see the dirt.

I will also say that if drag racing is what this is meant for you will want more adjustments than pinion angle. Changing Instant Centers and anti-sqaut is the key to gaining the edge with drag racing suspensions and can only be done effectively by chaning the mounting locations of the links....hence the many holed brackets.

I will also would dispute the axle wrap being a concern off-road. There are rock-crawlers out there with links mounted like you have and do fine. Yes there is more stress (tension and compression) on the links with smaller speration lengths at the axle, but if quality materials were used it shouldn't be an issue.

I guess my advise would be to decide if you want an all around street/offroad vehicle, or do you do you want a drag car. Then adjust what you currently have to meet the needs of the recreation you most plan to do.

I.E.:

Drag racing FJ40: Change the link mounting at the axle for below centerline with more adjustment, ditch the 4wd if you want to limit brakage and torque robbing from the extra gears

Street/Offroad FJ40: Raise the front frame lower link mounting to eliminate the rock catchers, redo the trasfercase crossmember for a close to flat belly, and go to a nice coilover shocks and ditch the leafs and the springed shocks of gayness.

 

[HI^C]

Above

huh and what? This is like a 10' breaker bar on a 1/4" drive rachet. There is less then approx 3"s of speration, might hold a stock sammy or yugo (LMAO) but 5 grand launches at "545hp" or skinny and a few small ledges. this is not exactly a light and little ballerina.

And the rest is dust in the wind.

You can easily do both 4x4 and drag race. You seen the video of the dodge ex cab 4x4 running 10.41 1/4s oh and in 4x4, and this is an older video. this is an example you do not have to run in 4x4.

you can also 4x4 with limited ground clearence, if the link mounts are in the way then the crossmember is too, then alot of other things need to change. not as simple as a crossmember redesign, LMAO.

I do like using the torque mount, but do not like having any of this drivetrain solid mounted.

LMAO "springed shocks of gayness." coilovers? ha ha. again could be used to firm up the rear.

I do thank you for this evenings entertainment.

 

[cruiserrg]

Above

huh and what? This is like a 10' breaker bar on a 1/4" drive rachet. There is less then approx 3"s of speration, might hold a stock sammy or yugo (LMAO) but 5 grand launches at "545hp" or skinny and a few small ledges. this is not exactly a light and little ballerina.

And the rest is dust in the wind.

Please read my post closely I qualified the separation concern as off-road, and not 5 grand drops at the drag strip. Yes you might do a launch like that in a rock crawling comp, but me thinks this rig won't be in UROC any time soon. You might want to check out some of S&N Fabs 4 links they are similar and have been used off-road

You can easily do both 4x4 and drag race. You seen the video of the dodge ex cab 4x4 running 10.41 1/4s oh and in 4x4, and this is an older video. this is an example you do not have to run in 4x4.

Yeah you can, but you still have all the extra weight and spinning a few more lbs of gears. Not ideal for the drag strip. My post was to get to the point of if you want of REM deciding of he wants a something great at one thing, or mediocre at everything.

you can also 4x4 with limited ground clearence, if the link mounts are in the way then the crossmember is too, then alot of other things need to change. not as simple as a crossmember redesign, LMAO.

I do like using the torque mount, but do not like having any of this drivetrain solid mounted.

Never mentioned simple to redo the ground clearance issues. Yeah you could wheel it like that by who would want to when your get hung up on the first pebble.

LMAO "springed shocks of gayness." coilovers? ha ha. again could be used to firm up the rear.

I do thank you for this evenings entertainment.

I hate them suckers. My thinking with ditching them for coilovers is who in there right mind would want leaf springs on a 4-linked off road rig. I could see 1/4 elip, but depending on the street time its sees may not want 1/4 elip.

Glad I could entertain.

 

[HI^C]

s and n fab website, suspensions, look not one setup shows 3"s or less seperation on the axle. why? BTW while there did anyone say something about tree stands.

"extra weight and spinning a few more lbs of gears." again the current setup is not a light and little ballerina. "mediocre" So i guess if he does not compete in ihra or uroc this is a total failure?

This thing could easily drag and 4x4 with ease, more ground clearence then stock, more tire, more power etc.... Bracket drag if he wanted for comp, or just run test and tunes. Built to enjoy more then a trailer and min. use, or garage time only, i even like it to ground pound a bit. Reasonably fast for a brick, and still have 4x4 when needed.

sometimes, i just love to visually see some of your pocket books in words, ha ha.

 

[cruiserrg]

HI-C, yep I was mistaken saying S&N, I actually got digging and it was camo's rear suspension that had less than most vertical serpation. I attached a pic of his to illistrate that they can be built with at lot less sep than some think.

I guess I have never been happy with an "all around rig". I tend to build my junk to be better at its desired purpose, also never cared to take my junk on the street either.

big 10-4 on the pocket book, if only I could make more $$ just typing replies. Then I would have more $$ to sink into my junk. To each his own.

 

[rem_7mmSTW]

To clear up...

I live in south Louisiana (completely flat). Our 4-wheeling fun consists of either mud-racing or mud bogging in what we call black-jak clay, marsh, or bad farm land. As much as I would love to rock crawl, the only rocks we have is little ones on drive ways. The only obstuctions we encounter is the mud itself when bogging. When your axles drag it usually comes to an end. But, high horsepower, swampers, and some good driving skills is usually king. I really don't plan on even doing this with the rig until it is inevitable (backed in a corner by some of my jeep owner buddies).

I travel extensively for my job, so hooking up a trailor to haul rig out of state for weekend isn't in the cards.

I understand both design principles. I purposely designed the link system as a hybrid.

Enjoyed the good clean debate.

Thanks for the support Rueben.

 

[Mace]

I want to know why 3 or 4" of vertical seperation can't control axle wrap as well as say 8" of seperation at the axle??

 

[lowtideride]

I want to know why 3 or 4" of vertical seperation can't control axle wrap as well as say 8" of seperation at the axle??

im sure it could too...more stress tho...



and dude you are a few hours from tellico...so yes you can rock crawl!!!

 

[HI^C]

large combination of things.

fundamental geometry, load psi, strain on the materials, etc...

Without leaf springs to help locate the axle like in this case, these links and link mounts have to handle a hell of a lot more then just axle wrap.

Major and easy example is leverage, similar to standard rachet vs breaker bar. more seperation would be better.

very little overall weight, low hp, small tire size etc.... might get away with 3" or less sep, but in no way would i ever suggest it or do it myself. And i will say i will be the first to laugh and leave your ass when it breaks, hard truth, LOL.

More tree stands!!! put a beverage holder on those things. damn those are just ugly crap. Sig line. factory toyota torque arm mounts have more appeal! little but some.

technically, you can also have horizontal seperation on two points of the axle and achieve the same results, but not currently in the link setup that we are talking about.


even with good amount of seperation, the strain on materials is huge, ripped 2" .120 apart lengthwise, 1.75 .120 perp. on two tubes, then 1.5 .25 perp on a u tube. three different rigs, each with at around 8" or so seperation, two v8 and gearing, one 4 cyl, all fully bodied. all this in the last month or so on two outings. MORE GUSSETS! lol oh they are all leaf sprung.


"if only I could make more $$ just typing replies. Then I would have more $$ to sink into my junk." sounds like a business venture, i am in.