Moving rear end back

[1320racing]

Would it make sense to see if a leaf spring manufacturer like Espo could relocate the centering pins on the leaf spring assembly further back to better center the rear in the wheel well area? Adding spacers to the front, altering pinion angle and changing and or relocating stock type shackles and hardware is something I'd rather avoid if there's a better alternative. I will be replacing my driveshaft anyhow so shaft length isn't a concern. Hoping someone has already tried this and can offer their experience, good or bad. I have a 1974 360 Dart Sport and the wheels/tires are too far forward, not even close to being visually centered when viewed from the side. Thanks, Ralph

 

[Woods74]

Call em up and see, good question.

 

[HemiDenny]

You are only talking maybe 1/4" ?

On the HemiDemon, just to get a little extra room, We installed a 1/8" Mancini reinforcing plate as a spacer. I tried doubling up with 2, but did not have enough stud on the front spring hanger. Tire is P275/60/R15 27.0 tall...10" wide...on 8" rim/ 4.5 backspacing. Factory tubs w/ 1/2" offset hangers.

Simple and effective and about all the tire you can stuff in a factory opening

Keep in mind, the further back you place the axle centerline....the less bite ( traction) you have

 

[RedFish]

measure closely regardless. Reason being, they aren't the same on both sides.

 

[69MOPE]

You are only talking maybe 1/4" ?

On the HemiDemon, just to get a little extra room, We installed a 1/8" Mancini reinforcing plate as a spacer. I tried doubling up with 2, but did not have enough stud on the front spring hanger. Tire is P275/60/R15 27.0 tall...10" wide...on 8" rim/ 4.5 backspacing. Factory tubs w/ 1/2" offset hangers.

Simple and effective and about all the tire you can stuff in a factory opening

Keep in mind, the further back you place the axle centerline....the less bite ( traction) you have

Moving the rear forward (altered wheelbase cars) was done for a reason. Moving it back hurts weight shift and traction, plus it looks terrible. Why not just reshape the front of the wheelwell.

 

[BigBlockMopar]

You could also perhaps just drill another hole a little forward in the axle's springperches as a new location hole for the pin.

 

[Oldmanmopar]

The front mounting surface on abodies are all over the place. My Duster was 1/2 inch off from side to side. I had to move the passenger side back using a 1/2 aluminum plate. I also moved the quarters front 3/4 inches. performance cars that came with a sure grip were pretty close but I have still seen them a little off . The main cause for your car going to one side while doing a burnout. Adjusting this will help with traction and launch

Look under your cars and compare the mount distance difference to the hole in the frame directly in front of the mount. You will all be surprised. Moving the front back was the easiest way to get the correct positive shackle angle in the rear.

I corrected mine with shims then double checked several times by measuring and launching the car with the factory mounts before welding the spring mounts in for the relocation kit. My 340 4psd. cars demon and Duster are also off One 1/8 and the other 1/4. They will be corrected and moved back for 28 10.5's My My orange Duster is running 29 14.5's .

 

[HemiDenny]

Moving the rear forward (altered wheelbase cars) was done for a reason. Moving it back hurts weight shift and traction, plus it looks terrible. Why not just reshape the front of the wheelwell.

I'm with ya'....however, I do not think an 1/8" will stand out or effect the launch too much....

as for me...and you guys already know this, I just do not believe in cutting up or modifying the stock sheet metal.

 

[rumblefish360]

Moving the wheels back in order to center the wheels isn't a whole lot IIRC. I thought there was a block you could use to do this. The rearward movement is t going to kill. If he was racing for money, this question would have never been asked and what would have to be done would have been done. Anybody who is serious is not doing this.

 

[jrlegacy23]

You could also perhaps just drill another hole a little forward in the axle's spring perches as a new location hole for the pin.

That is what I did. You also have to drill the hole in the shock mount that goes under the springs. I moved the rear back 1 3/8" back. I have some pics in my build of how it looks (link in signature).

 

[jrlegacy23]

Here is one pic with a 27" tall tire:

 

[roccodart440]

Moving the rear forward (altered wheelbase cars) was done for a reason. Moving it back hurts weight shift and traction, plus it looks terrible. Why not just reshape the front of the wheelwell.

I call BS and BS.

1. I've done both. Stretched the quarters on one car and moved one back 1.5" on another. It makes no difference in traction whatsoever.

2. So long as the the tire is the right size you will see no difference.

3. If you want to retain the factory trim pieces you have no choice.

 

[rumblefish360]

Is that moved back Rocco?

 

[Commando66]

That is what I did. You also have to drill the hole in the shock mount that goes under the springs. I moved the rear back 1 3/8" back. I have some pics in my build of how it looks (link in signature).

Do your shocks bind up or did you mount the shocks differently?

 

[mderoy340]

On my 67 Dart I moved the rear back 3/4" by redrilling the spring perch hole. I needed a driveshaft cut anyways so it made sense to move it back. Shock plate hole had to be notched and when I installed the fuel tank I kept it as far back as I could for shock clearance. Car handles very good street and strip driving. If you do this triangulate your measurement off the torsion bar cross member to get the rear straight.
I run 255/70/15 29.1" tire on the street to kill the 3.91 gear. 27" drag radial at the track and the car hooks with a 1.65 60'. Mancini Racing SS springs and cheap Monroe gas shocks.

 

[jrlegacy23]

Do your shocks bind up or did you mount the shocks differently?

No binding at all, shocks clear fine. I did need to dent the gas tank a little to clear the diff, but no big deal.

 

[turbofreek]

moved my pin hole back 1" on the leaf themselves for added tire clearence and open centering. shims under the perch can fix any pinion angle issue you may get from this. i also have adjustable front amd rear shackle perches to move my stuff around for track conditions. top pic moved back 28" tall 275 drag radial bottom pic you can see my front shackle the first time i did them. second hole made to allow a 1 inch drop of the front section of the leafs. i now have a multi function setup that is adjustable by 1/4" per grove like mustang team z stuff. way cooler and more adjustable.

 

[ssba]

Hey turbofreek I haven't seen a traction device quite like what you have shown.
I can see how it will lift on the front spring eye while resisting housing wrap up.
Does it also press down on the leaf behind the eye like the caltrac's ?
Hard to tell by the picture.

 

[turbofreek]

Hey turbofreek I haven't seen a traction device quite like what you have shown.
I can see how it will lift on the front spring eye while resisting housing wrap up.
Does it also press down on the leaf behind the eye like the caltrac's ?
Hard to tell by the picture.

no it only pushes at the front of the lewf under the eye bolt location. the mount that bolts to the leaf allows a pivot point so no binding can occur. smithracecraft assassin bars. same price as the caltrac only way more advanced and adjustable. they also dont bend leaf springs over time like the caltracs have been known to..

 

[ssba]

I do like the looks of it. Never cared for the bending spring behind the eye design.
That housing that is blocking the part in question sure is purity also.

 

[roccodart440]

Is that moved back Rocco?

The purple car is moved back 1.5"

The silver car has stretched 1/4's.

moved my pin hole back 1" on the leaf themselves for added tire clearence and open centering.
]

This will potentially affect the ability of the car to hook up if you don't run a traction device because you are extending (read weakening) the front section of the spring.

 

[turbofreek]

This will potentially affect the ability of the car to hook up if you don't run a traction device because you are extending (read weakening) the front section of the spring.

you say weakening and i say traveling allowing more movement to be useful for traction. one big issue with mopar is the front section is short not allowing enough wrap up to be useful with traction bars. remember mopar designed these to run with a snubber back in the day. so they didnt want wrap up of the leaf. in todays world wrap up is leverage against the tire with a traction bar. the longer the front segment the more leverage that can he applied with a traction bar as it attempts to wrap itself up. i also will only attempt to see how this works once or not at all before buy monoleafs with the pin where i want it. after all my setup is of higher power than most will ever be shooting for.

 

[roccodart440]

I agree with what you are saying 100%. My point being the traction bar or device will most likely be a must.

 

[turbofreek]

I agree with what you are saying 100%. My point being the traction bar or device will most likely be a must.

1" inst going to be much to do anything to effect spring ride etc.. its the length of your thumb from knuckle to nail tip usually. that isnt as much as one thinks it is. one should consider traction bars over a snubber in any performance minded setup no matter what. because it controls the actual spring wrap personally not the center of the pinion nose. makes a massive difference and can be more controlled and consistent. im sure old guys will argue and i understand as the snubbers work but have limits. its just not 1068 anymore and technology has moved on beyond, way beyond.

 

[replicaracer43]

1" inst going to be much to do anything to effect spring ride etc.. its the length of your thumb from knuckle to nail tip usually. that isnt as much as one thinks it is. one should consider traction bars over a snubber in any performance minded setup no matter what. because it controls the actual spring wrap personally not the center of the pinion nose. makes a massive difference and can be more controlled and consistent. im sure old guys will argue and i understand as the snubbers work but have limits. its just not 1068 anymore and technology has moved on beyond, way beyond.

And somehow, despite all that, there are still mopars running well into the 8s in the 1/4 with nothing more than super stock springs. Sometimes simple works just fine.