Spring behind axle w/ wisbones-how do you do it?

[sedan_dad]

I saw this pic in another post and really like the front end set up.It looks like the perch bolts go through the wishbones.This set up would be great on my T.
I have a stock 40 axel and split bones that I want to use.Anyone have close up pics of this set up?

[Unkl Ian]

You can start here:Eyeball's site (http://geocities.com/kustom1948/roadster4.html)

[sedan_dad]

I went to Eyeball's site and the pics there are real helpful.His comment got my attention.
[ QUOTE ]
"So I am going to mount the spring onto the split wishbone. (Against the advise of people that know alot more than me.)

[/ QUOTE ]
I've seen this done before .Will I regret doing it this way.Anyone living with this set-up?

[lowsquire]

I just walked in from the garage where I was mocking up this exact setup for my A !
I want to keep the perches close to the axle,about two-three inches behind it ,as im keeping the frame horns and want the axle to be still close to under the highest point under the arch in the rails.
The problem Im encountering is clearance for the steering tierods,as the spring ends up directly above it.Should be able to overcome that though.
Im trying to get it as low as possible without suiciding it,as it sits now the rail bottoms are about 9" off the deck,which is fine,Im using a stock 46 axle, so I can always put a dropped one in later.With a 4" channel the highest point of my roadster pick up body will be about 33" which is pretty low.(excluding screen of course)
Im also using 46 bones which have a bend in the front to clear the steering,kinda handy.
Id also like some opinions on this setup....

[TINGLER]

Sorry I can't help with answering questions,
I just want to pipe in here and say that I too am interested in doing this.

I have a stock '41 Ford front axle and it will be mounted suicide style on the front of my roadster project.

I have the option of going with the spring over method, or maybe the spring behind set up pictured above.

I also have seen this before and am wondering what the pro's and cons are involved?

Any ol' pro's out there wanna answer a few people's questions????

JT.

[lowsquire]

I guess the pro's are that the spring perch is about 3" lower relative to the axle, and if youre using a crossmember and horns, gives you the same amount of drop as a rather spendy dropped axle.
With this set up your axle moves forward about 3" or more,which is good or bad,depending on what youre after.

the cons would be the connection to the bones has to be bloody solid,and it puts forces on the bones they werent designed for.
I'm running the perch pins right thru the bones and welding each side,then trimming off the threaded bit.Be aware that the holes have to be at a slight angle to compensate for the bones not being parallel (they angle in when viewed from above)but this may only be on a later,wider axle.
I guess there is also more stress on the bone to axle bolt-im having these machined from high tensile steel just to be sure.

I think if you keep the perches close to the axle as practical its safe.

The photo with the red bones above is too far back in my opinion,but im only a mechanic, not an engineer http://www.jalopyjournal.com/ubbthreads/images/graemlins/smirk.gif

in last years Hop -up annual there were two 32 coupes that were mentioned as having this setup,(in the seven at mirage article) but no close up pics unfortunately.

Hope some other opinions come up...

[Unkl Ian]

[ QUOTE ]
Will I regret doing it this way.

[/ QUOTE ] There should be something on this in the TechOmatic,the subject comes up regularly.Basically,if the spring or shackle or perch breaks your frame rails will jam into the steering.Or if the tie rod is out front,the frame and oil pan will dig into the ground.BTW,this is the same set up I plan on using.

[Unkl Ian]

Tuck was considering this style for his roadster.I don't know if he changed his mind or not.

[TINGLER]

I figured as much concerning the frame digging into the ground upon breakage......such is life with a suicide front end, eh? http://www.jalopyjournal.com/ubbthreads/images/graemlins/blush.gif

Anyhow, the next question I have (hope I'm not hijacking this post too much) is what is the best way to make sure this set up does NOT come loose from the bones?

I like what was already mentioned, bolting AND welding.

Any other tricks or sure fire solutions concerning that area?

[Unkl Ian]

If the load is carried by both sides of the tube,and there are no stress risers,it is less likely to fail.

[lowsquire]

Good advice Unkl,
Dunno if its because im using a later axle and spindles,but the axle will hit the chassis and leave an inch or so down to the steering tierod,so i guess im fairly safe.

[TINGLER]

I just rambled through some of my files and found these two pics.
first one is the Shine truck.
Second is an unknown T-bucket.
Anyone see any problems with these set ups?

[TINGLER]

The T-bucket

[lowsquire]

Doesnt running the steering rod in front fuck up the ackerman effect?
the distance back to the spring from the axle on that T worries me...
and Shines truck looks a little spindly to me,The weakest link appears to be the bolts from the batwing to the hairpins,as all spring force has to go thru these...not a critisism, just looks fragile.

[Unkl Ian]

The T-bucket needs a longer spring,so the perches don't have to stick out so far from the bones.

[Eyeball]

I am very happy with the set up on my roadster. It is not mounted like the pic shows, that was just in the mock up stages. I used 5 degree perches from TCI. and welded a threaded bung into the bone. Works great for me.

[TINGLER]

Definitely things to think about...

Anyone else got any pics?

[Terry]

I haven't done it yet. Still in the parts gathering process. But here is a picture of the bones I plan on running. I have read and heard that mounting the spring on the bone drops the front as much as a 3 or 4 inch drop axle. These bones (46 - 48) look to me like I will get a bit more with the step.

[BigJim394]

I've seen plenty of cars that used this type of set up and had no problems, but most of them were fairly light cars.


That said I was around in the early 70's when a lot of Ford front wishbones got cut up to extend old Harley Springers during the Chopper Craze. As another poster said, the bones were not designed for this kind of load. I have seen some fairly significant differences in wall gauge thickness in the old Ford bones that were cut up. I also saw some that got pulled out of piles of bones that had been sitting for years in old junkyards. Some of those had some rust problems internally from rainwater getting into small holes that had been drilled in the bones. You probably want to reinforce the area where you are going to weld the spring perch and make sure the welding is "spot on".

[sedan_dad]

Thanks for all the feedback.It looks like this set-up just might work out alright on a light car like the T that this is for.

[UKAde]

my car has the spring mounted on the wishbones, in an attempt to get the spring behind the grill and the axle in front of the grill,,,
my track rod is behind the axle but space is a bit tight,

my spring is a little long as the shackles are at too shallow angle

but I havn't run it yet, so i can't say for certain how it will be yet, but I feel it is a sound system

Akerman stering can still work with the trackrod in front of the axle but the line drawn through the track rod ends through the king pins still has to intersect on or aroung the rear axle center



I'm not sure about using clevises in bending on Shines truck, I thought they were only for use in tension or compression, but with the spring monuted on the wishbone the spring force is through the clevises ,,

UKAde

[abomber30]

That's my roadster in the first pic. Every car I do has that setup It seems to work for me. Never had a problem. Lemme tell a open wheel car is dangerous and anything can break on them so do what you want I just do what I do cause it looks cool and it gets em low and performs on the street well. thanks drew

[abomber30]

nuther

[LUKESTER]

Heres how I did mine with hairpins, you could do the same with wishbones, but I'd weld a sleeve in the hole that you drilled in the bones. My "perch bolts " are 5/8" bolts TIG welded to schedule 80 pipe. I guesseted my hairpins, and used sleeves to weld to rather than welding right to the tubing. I have been pounding it to hell and it seems to hold up just fine. as you can see in the pics, I was unsure of how it was going to work so I added a couple of "adjustment holes" for the setup.... but it ended up right where I wanted it. I wouldn't be scared, just weld stuff good and use "good bolts"... Lukester

[LUKESTER]

here is another pic. ... Lukester

[hudson_hawk]

i have a question. i have an axle from the 50's that has the spring mounted to the drop axle (tube) on the top. i assumed mine was wrong because if its mounted staright it will slap the axle.

does this mean that it should be mounted at an angle?

[Tman]

I am in the process of doing this to my touring (ditched the 1/4E setup). What I am doing is welding a piece of thickwall DOM tubing into the bone. A T-bucket style spring pivot is then going through it with the nut on the outside of the bone. It will pivot like an adustable spring perch.

I am still up in the air however on my tie-rod location. When my new spring gets here I am going to get creative with it. I am hoping by dropping my 40 steering arms I get enough clearance so my frame doesnt bottom out on the tie-rod!!!!!!

[Unkl Ian]

[ QUOTE ]
I am hoping by dropping my 40 steering arms I get enough clearance so my frame doesnt bottom out on the tie-rod!!!!!!

[/ QUOTE ]
I was planning on running the tie rod on the back,both for getting the desired amount of Akerman and for appearance.The spring was going on the bones right above the tierod.
But now Kustombuilder has me all confused with his 7" dropped axle plans. http://www.jalopyjournal.com/ubbthreads/images/graemlins/cool.gif I wish I had a brain.

[Tman]

Unk, that is what I am planning to do exactly. By dropping my arms they should get a little shorter which will let me move the axle closer to the grill (a look I am starting to dig)

Lukester, how much travel does you front end have? I mean, when the spring compresses how far does the frame move downward?

[Unkl Ian]

[ QUOTE ]
... which will let me move the axle closer to the grill.

[/ QUOTE ] Jimmy Shine made longer steering arms,out of steel,to get enough room for the rad shell between the axle and tierod. http://www.jalopyjournal.com/ubbthreads/image_uploads/185595-4-4-5.jpg

[klazurfer]

OLD-TECH :

[Elrod]

So, that spring perch is welded through the bone? Are they going to cut off what is sticking out, or does that attach to the steering arm, for excellent straight shot driving? http://www.jalopyjournal.com/ubbthreads/images/graemlins/grin.gif

[zibo]

on shines and lukesters,
are those 2x2 5/16 bolts on each side strong enough?
I have a roach rod I'm slapping together,
with the same idea,
but with cheesy speedway hairpins,
and am not trustworthy of those bolts holding up
the whole front end.

does anyone drive far with this?

tp

[Tman]

Yeah the perch gets cut off! I am using an actual spring hager meant for a T bucket. The bolt is 5/8s OD. I like to err on the side of overkill if I can. Also, the way my shocks are mounted they would bottom out before the frame hit the ground in case of a catastrophic failure of the spring.

[Unkl Ian]

[ QUOTE ]
does anyone drive far with this?

[/ QUOTE ]
Last I heard,Jimmy Shine had 1000+ miles on Frankenshine.Which isn't a true test of durability,but it does work.
Even so,I think the design test the limits of the materials.The safty margins are not as large as some would like.
I doubt they are El Cheapo No Name brand ungraded mystery bolts.Good bolts will be at least 3 times as strong as cheap bolts.

[BARNETT]

This is great timing for this subject...gonna start making the frame for the jalopy next weekend! I know NOTHING about hot rod type suspension, so any and all info is going to be very useful.

[Unkl Ian]

[ QUOTE ]
and am not trustworthy of those bolts holding up
the whole front end.


[/ QUOTE ] I'm sure someone will correct me if I'm wrong:
The bolts are in double shear,so they shouldn't be a problem.
The clevises are the weak point as they are loaded largely in shear.
In nice round numbers,if the truck weighs 2600 lbs with 1200 pounds on the rear axle,
1400 on the front axle.
That gives you 700 lbs on each front tire.So each clevis has to support 350 lbs.
Now if you take the Minor Diameter of the thread,multiply by Pi to get the area,then multiply by 30,000 PSI yield strength you get the yield strength of the thread.Divide that by 350lbs to get the safety factor. Who has a calculator? http://www.jalopyjournal.com/ubbthreads/images/graemlins/grin.gif
PS I've left braking torque out of this example for simplicity.

[zibo]

UI
sounds good...
tp

[Elrod]

Why couldn't something like this be built? Put a longer perch like bolt through the bone and then build out a sort of C style mount that goes above and below the bone and axle. Then you mount the horizontal perch into it. It could even be welded onto the bones if you were worried about that setup being weak.

[shifts]

Does this setup use the original spring or one a little shorter? Looks good. Dave

[HotRod31]

Unkl Ian, multiply that 700 lb dead load x 80 MPH + a 3" pothole & you get a live load that would raise a little concern with me. http://www.jalopyjournal.com/ubbthreads/images/graemlins/grin.gif The one problem I see is that by BOLTING the batwing to the axle Then putting a side load from the spring you are creating a Hinge effect ? Which would multiply the load on them clevise's Seems to me it would be stronger with the bat wing welded. I know that creates yet another dilema on a beam axle.
(my opinion applys to wishbones not stock bones)

Later, Mark

[Unkl Ian]

[ QUOTE ]
& you get a live load that would raise a little concern with me

[/ QUOTE ]
That is where the safety factor comes in.Carrol Smith talked about safety factors in one of his books,and gave values for racecar suspension,roll hoops,and compared these to production street cars.
Jimmy Shine might have made his own clevises from some fancy heat treated alloy.Or maybe he's just very brave.
Another solution might be to use the heavy steel parts from the front of a production wishbone,and weld your hairpins to this.If it was executed properly,it would look acceptable and be plenty strong.
How did people attatch hairpins before batwings were comercially available?

[Tman]

I understand your concern Mr Hawking...err I mean Unk http://www.jalopyjournal.com/ubbthreads/images/graemlins/grin.gif But while we are debating this shit Jimmy is racking up the miles and laughing his ass off at us!!!! The way I see it we all have to build to our level of comfort. My setup has a little more beef engineered into it, that green T Bucket has quite a bit less!

I really enjoy this thread since I am knee-deep in this very thing right now. I will get some pics up as soon as mine gets together. Just waiting on a spring...hopefully tomorrow.

[Unkl Ian]

I went through a similar design problem with the Dumb Fuck Engineers(tm) where I was working.
To meet the safety code,the part I designed had to withstand 5 times the maximum working load without complete failure.
The Dumb Fuck Engineers(tm) told me the 5/8" cap screw wouldn't handle 3000 lbs in shear.I did the math,not good enough for them because I didn't use a computer.So I built a test fixture and proved that a 1/2" cap screw would handle over 10,000 lbs,without any visable distortion. http://www.jalopyjournal.com/ubbthreads/images/graemlins/grin.gif
They still didn't like it. Clowns.

[Tman]

So my 5/8ths spring hanger going through 1/4" wall DOM that is welded double shear is OK? Thought so. I will post pics.

[Tim]

to the guy wondering about his axel and spring being straight up and down,

you put the degree into the crossmember or whatever mount your using to hold the spring;)

tim

[zibo]

tman uses stock style spring perches.
these have 5/8" holes.

shine and lukesters use 5/16 I think bolts,
but two on each side.
I know that on the cheesy speedway kit I obtained,
(on a trade for krapwerk)
is advertised as being under 1800 lbs (I think)

that is on a stock set-up,
where the spring is attached to the axle,
NOT the hairpins.

Shine's and Lukesters setup,
mounts on reinforced HAIRPINS,
that rely on clevis + bolts.

I know that the shinemobile was a trailerqueen,
even in the early days of its showtime.
And even the pics in ROdders Journal
were obviously before it was running or finished.
(Driving it hard for occasional short distances
is different than daily driver/long distances)

Therefore I would have a trust issue with that set-up
(unless lukester can enlighten me/us)

Now I think the set-up on LENO"S tank car
it is a semi-elliptic hairpin straight axle.
http://www.motortrend.com/motor/autoshows/events/112_0309_accs_80a_z.jpg
http://www.detomasopantera.com/images/beast1.jpg
http://www.lamborghiniclub.com/pasa03s.jpg
the TWO half springs are mounted solid on the axle,
with no spring shackles either.

that looks unquestionably stronger
than a true suicide mount

I think I might try that one.

yawn,

tp aka zibo

[bobbleed]

This is way I did it on the Bleedster. It's kind of a hybrid
beetween a suicide and a traditional set up as I retained frame horns. I've never seen another one set up like this and I think it worked out well. We did the H-Bomb the same way.

Basicly used a 7/16 bolt welded to some tubing for the perch. (It was welded by LukesSucker the WelderFag so I know it was welded good.) That is put through the wishbone, which was strengthened with tubing.

The difference between this set up and the others is I used a conventional lower shock mount that mounts to the cut off perch through the axle. I flipped it around backwards to place the shock where I wanted it. This way there is no added stress on the wishbone and it looks pretty good too.

I figure if the spring mount was to break, the shock would hold it up, and if that was to break, the frame horn would land on the axle and still hold the car up.

I guess it is a suicide front end with some saftey catches built in.........

To be honest I don't think suicide type front ends look that good, so this was a way for me to slam the car and keep
a traditional (kinda) looking front frame/ crossmember.

http://photo.starblvd.net/bobbleed/1-1-4.jpg

http://photo.starblvd.net/bobbleed/1-1-5.jpg

[Tman]

Bleed, thanks for the pics...looks a lot like what I got going. A question though..........how far does that thing travel up and down?

[bobbleed]

Probably about an inch and a half. I spent a lot of time jumping on it and it takes alot to bottom out.
I'm going to add some small rubber stops to the bottom of the frame horns.

I think it will work out pretty good.

It's finally coming home from the interior guy this weekend so hopefully I'll be able to drive it soon and see how it all works.

[Unkl Ian]

Bob:Nice work.
Would it be possible to use dropped steering arms and run the tie rod behind the axle,under the 'bones?
There is probably a reason you didn't do this.
I want to avoid having the tierod out front if I can.

[Evel]

Dose it turn in the right directon???? http://www.jalopyjournal.com/ubbthreads/images/graemlins/laugh.gif

[Evel]

I guess it don't turn in any direction yet.

[Elrod]

How about this coupe at VLV 03? They have the spring way below the bones.

[Elrod]

close up

[sedan_dad]

Thats an interesting setup.Not too sure I like the looks of it.You know with the shocks out ther front and center.Even uses the axle as the lower shock mount.

[roadstar]

Bob, That setup looks great. That puppy has come along fast since I saw it at the pileup. Can't wait to see it done.

I saw a 32 chassis going togeather at a local shop that I really liked. The axel was under the front x-member that was flat and in the stock location. The the spring was mounted behind the x-member with a suicide style mount coming off the back of the x-member. The spring perches were built into the batwing. So it basicly left everything looking the same as a normal 32 front end but took the spring off the top of the axel. Also the frame didn't need the usual c-notch for the spring clearance. this perticular chassis also used a dropped I beam. I'll try and get a pic.

[bobbleed]

HaHaHa I sure hope it steers the right way!

I think I could run dropped steering arms but the problem is the tie rod will end up going right under the spring, so the would have to be SUPER dropped. I have an issue with the steering arm being the lowest point on the front end as well....... It seems you definatly need to keep it above the scrub line.

Because the grill shell sits right behind the steering arm, I think it looks OK. I still might change some stuff around.

I've got some top secret ideas for My Coupe that will solve alot of these issues. It involves mounting the spring to the batwing. I can't wait to start on that one.

[Unkl Ian]

TMan: What did you order for a front spring ? From who ?
Posies seems to have the best selection,that I've seen,
but I don't like the big ugly dimples on the ends of the leaves.

[Tman]

Unk, you mean the spring I was hoping to get today!? I ordered the Mr Roadster Spring, reverse eye from Speedway. It was a little less money than the Posies spring but I REALLY got it because it dint have the dimples!!!! I talked to a guy today about spraying a teflon like coating on all my springs. He says it wont wear off and will work better than the other solutions out there.

[Tman]

OK, my spring showed today! It was nice quality for $75. I will post some pics soon, I am getting close to having this thing rolling

[Unkl Ian]

Does Mr. Roadster have a site?

[yngrodder]

Im doing one right know and Im keeping track of all the parts you need and pictures for a tech. The 40 wishbone is the strongest one. and dont use a bolt to hold the spring perch. spend a little money and buy adjustable spring perches and cut them shorter and rethread it to make the threads longer. leave a shoulder on them and then take the wishbone cut a bigger hole in it. and then weld a sleeve in it so the pearch will rotate with the axle when it moves up and down that way you can move the axle farther out and the sping dont bind. As far as the adjustable spring pearches those are handy so you dont have to worry about drilling the hole in your wishbone at an angle. This will be a lot easier to understand when I get the pictures Posted and a full teck on it. any questions please Pm me. <font color="red"> </font> This way is a safe way to do it and the strongest that ive seen.

[Unkl Ian]

[ QUOTE ]
so the pearch will rotate with the axle when it moves up and down

[/ QUOTE ]
Adjustable perches are not suposed to rotate.
That's why they do not have any type of bearings.
Metal on metal will wear.

[J Man]

I looked for a Mr Roadster site a couple weeks ago and could not find anything. I think the may be exclusive to Speedway.

I was told that if using more than a 4" drop axle that ou run into problems with the axle twisting. The same person said that if you use 36" radius rods rather than the 27" it corrects the problem. Anyone else know about this. I was planing on using a 6" or 7" drop axle with the spring behind setup.

[Unkl Ian]

When stock axles were dropped,the ends got thinner.
The larger the drop,the thinner the ends of the axle.
I think 4" was a practical limit for the material they had to work with.
Anything more,and the axle wasn't strong enough because it got too thin.

A custom made axle can have as much material as you want,where you need it.
So 5",6",7" isn't a problem that way.

Scrub line might be a problem. http://www.jalopyjournal.com/ubbthreads/images/graemlins/cool.gif

[Toqwik]

how bout this ???

[Toqwik]

here

[yngrodder]

Before you order a droped axle you might want to do a mock up. because when you move the axle out front and up your already dropping it. Yes the pearch rotates with the movement of the car. as you move the spring behind the axle and the axle goes up and down with the pearch mounted in one place you are puting the spring in a bind. and that results in problems after a while. (Broken spring bolt Or Broke springs) it would take a while for this to happen but if you drive a car like it they are meant to be then you might as well do it right the first time. NONSUICIDE FRONT END The farther you move the spring back the more it will bind

[Toqwik]

I emailed you the pic I was trying to post, hope it comes out. Seems to me alot safer way to mount the spring behind than drilling thru the wishbones, will distribute the weight/load more evenly, hope it helps...Scott

[thirtytwo]

mr roadster is speedway's own little line of stuff , i cant see how differnt drops would affect twisting that much i think that person was refering to i-beam verses tube axle, i beam twists tube doesnt... at least not enough to even notice, that was the reason for four bar.. blah blah blah , anyway on a hotrod the suspension doesnt work much more than 3'' at the most the only time this becomes an issue is on driveway inclines if you have a ridgid chassis a front wheel will lift of the ground cause things arn't allowed to twist if this bothers you go with four bar or an i-beam, how ever alot of people use this setup and put up with it its on fairly steep inclines, i would rethink the 7'' drop however i built a 29 pickup with this setup and a stock 48 axle - 2" drop and its LOW... 7" would probely make it drag on the ground id use 36-48 bones too they are the heavyest ive seen it done on earlier ones and its dangerous , remember the weight of your car is now on the bone and not on top of the axle, eventhough the car is light the impact of hitting a pot-hole at 80mph is pretty severe make sure to over build it so you never have to second guess it , its not called a suicide axle for no reason

[thirtytwo]

thiss is how i did mine i used the bungs that were cut off the 40 bones and gusseted it alot, not as trick as alot of ones ive seen but tons more stury than lots of others, and nothing to buy either

[thirtytwo]

otherside

[3bytheknee]

First, a comment on Jimmy Shine's rod. I admire the clean construction shown in the various photos, no matter who built it or if it has been on a trailer. Nice work!

The photo posted by Unkl Ian shows the small clevises on the single blade (probably 3/8") batwings. An option is to use the double sided batwings such as those sold by Speedway. These use the larger diameter bolts, 1/2", running in steel sleeves and nylon bushings connected to the bat wings. These would be substantially stronger. Using hairpins or 4-bars will give a space to run steering rods. Springs, shocks, or coil-overs can be mounted to gussets on the hairpins. Like several others, I am in the imagineering process and gathering parts and ideas. I've committed and bought the 4" drop axle and the double sided stainless bat wings. I am leaning toward coil-overs connected to the hairpins but have not bought them yet. The object is to keep just the big smile of a tube axle out in front with as little clutter as possible. Thanks to all the contributors on this suicide axle thread. http://www.jalopyjournal.com/ubbthreads/images/graemlins/smile.gif

3bytheknee