How to make a stock rear suspension work?

Ok guys, a lot of you know I've had some 9 second street cars with ladder bars and 4 links but I built my current big block Duster for street cruising only, it has a nice mild pump gas motor with around 600hp or less.
I quit racing about 5 years ago and I'm starting to crave making a pass or two. My Duster is bone stock except the engine. I do have a motor plate and MP frame connectors bolted in, I may have my buddy weld the connectors in and may have him put a 6 point roll bar in even though I said I'd never do that to this car.

My question is, on my super tight budget right now, what can I do to make worn out stock leaf springs work?
I have Rancho single adjustable shocks. Where do I buy good leaf spring clamps? Should I clamp the rear section or just the front of the leafs? Use a snubber or not?

I'd like to order 35 spline axles and spool from DoctorDiff.
If money allows I might buy his half inch offset spring hangers so I can remove the 1/4" wheel spacers and stop the tires from rubbing the quarters when I have a passenger in the car.
I'm gonna have to upgrade my stock 7260 u-joints too.
I have regular passenger 275/60/15 tires so I'll need to buy drag radials or slicks, probably search for decent used ones.
I have factory 3.23 gears, will those hold up or should I save for new ones from DoctorDiff?

Any positive advice is much appreciated, I'm afraid this is gonna snowball into a money pit but with the new Dragway42 being built 40 minutes from my house I know I'm gonna want to drive to the track and make some passes!

pinion snubber and stiffen front spring section. I had a spring shop add a leaf under the main leaf that goes almost to the front eyelet and clamped. Seems to work OK?

Snubber one inch from floor?

No way on a pinion snubber. If you have one........throw it away so you won't be tempted to use it

Why not a pinion snubber

im about to be in the same situation as you, im putting my retired 340 back into a 71 duster i bought not long ago so i can have a simple cruiser. but im finding stowed away go fast goodies i forgot i had lol. Im thinking of adding a front half leaf to stiffen the front segment of the springs and unclamp the rear half so it can flex and use good shocks.

My pinion snubber on the Charger is maybe 1/2" from the floor. The setup seems ok running mid to low 12's. The new engine is overpowering the suspension now, so I'm looking to make some changes, maybe CalTracks and race shocks?

I would ditch the snubber. Add the half leaf and use the opportunity when you move the Springs in to get the pinion angle right.

The snubber is a bandaid for not having good shocks.

Years ago when I had super stock springs on an 11 second 340 car, I did not use a snubber. I thought it might be necessary to use it with stock springs.
I know with super stocks, if it ws set too close to the floor it would make the rearend pivot and steer the car everywhere.

As already stated, clamp the front spring section, remove snubber, trim top upper a arm bumpers down to about 3/4" tall. Worn or 90-10 front shocks. Make sure the rear shocks do not top out on launch. If you spend ANY money on it, buy GOOD shocks. As Monte has stated time and time again, this is the most important area to look at. At your power level the Viking shocks will work great.

Im running super stock 002/003 springs in the stock location,adjustable snubber, stock style shocks, 3.73 gears, and put 26x9.5x15 Hoosier Quick Times on at the track and runs low 11's and never have a problem. I dont think a spool is going to be very street friendly is it?

I would keep everything you have and buy some good shocks. My red car was night/day with good shocks. The old shocks sucked so much it bent the rear leaf spring segments and killed the u-joints over time.

Viking Shocks
Drag radials
HD u-joints

Check the u-joints often!

Sounds like a plan, I'll have to check out Viking's website.

As far as the spool, it's $100, any posi unit I would trust in a high10/low 11 second car would be expen$ive. I don't love a spool on the street but I ran them for a couple decades with no problems.

Shocks and clamp the front segments... if need
be add a front leaf if the springs are worn that
bad.. but stiffen the front segments as stiff as
you can make them(your ride rate is done on the
rear segments)

Who sells the leaf spring clamps?

Mancini

http://www.manciniracing.com/caspcl.html

Thanks Mike!

Viking's website doesn't have prices that I saw, I'll email them and get a price on a shock for a '72 Duster with stock ride height. Is this a coilover or regular shock? If coilover I'll have to get the correct spring rate too.

I wish Summit carried Viking since I have a gift certificate there.

Bob You will probably have $1000 in a "decent" pair of shocks these guys are suggesting. You might want to give Bondo a call he was an Afco dealer I thought and he could probably hook you up with some DA shocks for a little less money.
I still use SS springs and Rancho XL9000II on my car and it hooks pretty good but it may take a better suspension to get a big block A-body to hook.
Keep the Ranchos and get some Cal-Tracs
Gus

Those are not the type of clamps you need.


To make the stock suspension work you Will need to clamp the front sections of the springs, even more on the passenger side then on the driver side. The clamps you need are sold by a , cant remember right now, but its a roundy roundy circle track dealer. Ive even linked them one time before on hear.

Ditto. I would avoid the current crop of MP SS springs. Mine worked well for about a year but started sagging and twisting into an S shape on launch at the end of the season. I clamped mine together and tried every combo with 4 clamps and no luck. I'm going to Cal-trac style bars and split mono's for next year.

Snubber is a crutch. Never had one work..

I'm in the same dilemma. I wasn't planning on going down this path with my "street car" but it keeps evolving. Roll bar scheduled for February at the chassis shop..

Sport440, When I bought clamps years ago they were the heavy duty sandwich type, they were actually big enough to put a dent in my gas tank, I can't seem to find them anywhere now although I haven't tried real hard yet.



LOL, it's a disease. I've either got to make this car some what work as a street/strip car or just sell the whole car and start over. I really like the car though, it'd be hard to find another one this clean.

Here's some clamps.......


I'll probably go with these Jegs clamps.

This is what I used in the past.

without SS springs or eqivilant youll need the snubber or you will break ujoints ive been there.my 68 charger stock springs with front clamps pinion snubber 1/2from floor rancho 9ways set 6-7best runs 10.9s 1.50 60fts.ive gone mid 1.3s with SS springs CE 3ways on all four corners 6cyl bars trimmed bump stops 5-5.5"front end travel in my dart.the snubber is just a crutch but it works without having bars hanging down if you like the hush look.

I didnt look at the clamps.... are you talking CV Products
for the roundy round place

Proven formula for using stock style Springs:
Steel or aluminum bushings in the front eyes. Rubber or poly in the shackles. On the left side 4 leaves Plus 1/2 Leaf facing towards the rear. Two clamps on the rear of the spring not on the front. On the right side Four Leaves + two 1/2 leaves facing forward and two clamps on the front half of the spring, not on the back. Plus a snubber and good adjustable shocks. If the car veers to the right under power add another clamp to the right front. If it veers to the left take off 1 clamp from the right front.

Do the front metal/aluminum spring eye bushings squeak alot on the street? Just wondering.

No, not cv, It was Speedway, if I remember correctly. But They weren't actually listed as spring clamps. But they were like the clamps shown in Prosports 2nd Photo. They were like $3.00 bucs apiece.

Tried to find my link from prior posts, no luck.

Those were the kind of clamps I was referring to. If they were hitting your gas tank, were they just to wide. Were the bolts right up against the spring? You can grind and shape them for clearance. But you do want the dimensions of the clamp to be tight, so the bolts are right next to the spring as they pass through the clamp. Another option, as I did. I bolted the front section of the passenger side spring. As in, drill holes through the leaves on the front section of passenger side. Clamps only on the driver side.

Never ran a snubber on anything.......including my dads Super Stock car. We just had some spring packs we built ourselves at home. This is not rocket science here guys. The front segment needs to be REALLY stiff. That's pretty easy to do.

The only thing a snubber does is ATTEMPT the keep the front segment from wrapping, but does a crappy job of it. Make the segment stiff, get some decent shocks and it will work

Some grade 8 bolts and some 3/8" thick strap and build all the clamps you need

All the clamps are two 1/4" thick flat metal that are bolted together. You can make them DIY Clamps Or Auto Zone has these Clamps but I have never run them.
I use to run 3 clamps each side with a set of XHD springs that was with my Dana 60, 18 spline hemi box 440 RR/GTX. This setup worked well.

Here's a couple good videos that show what's going on with the rear suspension before and after a Caltrac setup.

Before caltracs

After caltracs

Yes they fit tight Mike, just needed trimmed or rounded off. But I didn't use them once I bought SS springs for that car. My current car has tailpipes so I'm sure everything will fit tight. On the passenger side I like the idea of drilling and bolting if the clamps won't fit but I'll try the clamps first.

My '71 street/strip Cuda auto (520hp) was all stock suspension, tired front shocks, clamps on the front segment of the leafs, adjustable p/snubber made to have 1/2" gap, stock perf rear shocks with extensions, longer rear hangers, did NOT overtighten bolts, it picked the front up every time and went 1.51 60's at 11.01 et's, weighed 3550lbs. Just cos a snubber is old tech don't mean it won't work today, cheap and adequate without spending big bucks, put SS springs on and adj shocks and you won't need the snubber.....my 2c

Thanks guys I've learned a lot on this cold boring Sunday, several good options to look forward to trying. Obviously this is an old school build(even have a purpleshaft cam lol) but it has been a super fun car that does rolling burnouts at 50 mph and does pretty well at car shows. Now I want to make some passes.


Will 30 spline aftermarket axles and spool work for 600hp or less, or am I way better off going with 35 spline?

Here's a pic of the family hot rod.

Thanks for the video.

How much preload did the bars have?

You can't just drill holes in the springs and bolt them together. Why? Because they are arched and bolted in the middle. When you de-arch them, but putting the car on the ground, the ends of the leafs move. So you CAN drill holes, but you have to have the spring compressed the same as it will be on the car when you drill the holes. AND it's spring steel. Damn hard to drill

You should be able to post a wanted ad for a set of 002-003 springs with everyone switching over to caltracs. I went 9.80's in my Duster 35 years ago with them and track prep was nothing compared to what it is today.

No. I greased mine fairly well and you really don't know they are there!

In my experience, poly squeeks more than anything.

Damn Hard to drill yes. Only did the passenger side. Makes the Front segment close to Solid. Just like you say that's needed, {need to make the front segment as solid as possible}.

It works. And yes, you don't drill the spring unless its compressed as the same as it will be on the car with it weighted down.

Basically by bolting the spring, it comes close to achieving the same thing as a traction bar/south side machine bar/etc. Bolting the front spring segment together is Less stiffer then the above.

I did not bolt the driver side together, no need.

As far as shocks, I use a air shock on passenger side with the stock suspension. The more PSI, the better the 60 ft. On the Flimsy stock suspension the passenger side of the axel trys to rotate Up, causing loss of traction the Fix More PSI in the passenger side air shock.

Not sure, they're just videos that I found on youtube.

I'd rather find someone that's switching to a 4 link and selling their caltrac system cheap.

Try a free ad on Racing Junk.

Well my setup is very low buck. Stock SS springs I bought from Mancini around 2009. I use the SS springs and just the longer ext MP shocks with no adjustments. And no pinion snubber as I tried it and it made no difference with the SS springs on my car. All other suspension is stock other then the CE 90/10 front shocks. I do feel the 6 point rollbar stiffened my car more then the frame connectors did so I would at least do a 6 point bar and frame connectors if I were you. At this point in my life cash is very tight so I make the best of what I can. Its nothing fantastic at all but for an average driver I drive to the track its does well enough for me to have alot of fun. My best 60 is a 1.50 with this setup at 10.70's as it usually 60's around 1.50 to 1.55 on most tracks. Dont set the world on fire by no means but I do get to race with some NSS clubs and have fun and I even win some rounds now and then. My cars weighs just over 3700 and I use the 30 x 9 Hoosier radial slicks and I also drive on them. I agree with most as get the springs right and good rear shocks and you should be able to hook it ok with a good tire and have alot of fun. Good luck , Ron

Do you have any pics of this setup, it sounds interesting.

Did you drill the spring with it installed on the car? or off?

Does the bolt stay tight?

All the old tech from the DC manuals still apply for a stock suspension. Stiffer front segment in the leafs. Long shocks/shock extenders so they don't top out. Rear leaf shackles oriented so it allows the chassis to rise when planting the tire.

Used those years ago and clamp every segment on the ft. if you can. No on pinion snubber made my car hop and unload the tires going low 11's and shocks are a great aid although I went and easy 1.33 last time out on old 5-way Ranchos in the rear and 90-10's up front BUT w/Caltracs and have seen guys running em w/multi-leafs w/good success..........I think I ran Imperial rear shocks before the Ranchos cos they were valved decent and extra long so as not to top out.........good luck........

I'm at about 540HP

With 3.54 gear @ 3,950, Getting 1.57-1.61 with 3.54

Got 1.63-1.66 with 3.23's in the 8-3/4 @ 4,050 pounds

Nothing broke.

All I have is XHD springs, Snubber, DANA 60 from Doctor Diff and the S-trac. AutoZone gas shocks.
No clamps removed or added at all.
Front shocks are AutoZone gas replacements.

**Do have a 1-1/8" front sway bar and 7/8" rear sway bar**

1350 yolk front and rear with 3-1/2" d-shaft

I leave @ idle and the car will just about print off time slips within .02

I've had better success with the Pro Bracket Radial 9x28 on a 15x7............the M/T 3754R works just as good but doesn't last as long

I've used two used sets of 3754R's and they work until the cords show..........same as the PBR

Running 11.28-11.38 @ 117-118 depended on weather.

Mike

The bolts stay tight and are on the front only of the passenger side. Holes were drilled while on the car with the cars own weight.

Clamps were used as well on the driver side spring.

Can show you pics, if you pm me a cell number. I think I used 3 7/8th bolts tieing in each front segment on pass, side.

Cool videos. They show what I hoped the Cal Tracs would do. Was the video taken of a 55-57 Chevy? That was a full frame car. Just wondering.

'67 F100

Cal tracs are the better way to go IMO, if you can swing it. As seen in the vid a stock spring setup will have a lot of rotation, even with clamps and such. Your 500 ci, will make sure of that.

Heres the link to to cheap clamps. It wasn't Speedway, it was E trailor. http://www.etrailer.com/Accessories-and-Parts/TruRyde/TRSL350.html

This link shows the 3.5 inch shackle witch can be used as a clamp. You will want the 3.1/8" clamp for a better fit with the A body springs. Add some grade 8 bolts for cheap from your local hardware if you go this route. Cant beat the Price. They look more heavy duty then the Jegs or other clamp you posted.

Wow that is cheap. Are they thick enough?

Much thicker then the clamps you showed. Look at the 3.1/8 clamp comparison below in the link, it gives a better picture. They are intended to be spring Shackles, so they Will be stronger, then the clamps you showed.

Ok cool thanks Mike

Hey Bob how have you been? Your car is looking great. My 3500 big block dart had 30 spline moser axles and spool. I broke one 8-3/4 gear set but never twisted a axle etc. The dart would only 60FT at 1.48 but at the time I had the wrong converter in the car.

Thanks Bobby that's good to hear. Been doing good and keeping busy, hope all is well with you.

That's great Bob. I am doing fine. I had to sell my 73 dart last year. But have a little 72 dart to mess with now. But it's going to be a long time before it sees the street. Lol