The Dodge Challenger Message Board

I HAVE A 73 CHALLENGER AND HAVE RECENTLY PURCHASED A SET OF 17 IN. BY 9 IN. RIMS FOR THE REAR.I HAD PREVIOUSLY PURCHASED A MP SPRING RELOC KIT.CAN ANYONE GIVE ME A DIAGRAM OR INSTRUCTIONS ON THE INSTALLATION OF THIS KIT.

They should have come with instructions.

But, regardless of that, there are better instructions with photos available, just follow this link;

http://www.bigblockdart.com/springs/springs.shtml

Best of luck with it!

Barry

IS THE ONLY REASON FOR MOVING THE SPRINGS FOR WHEEL CLEARANCE? I FIT 18 X 10 WHEELS ON THE REAR OF MY 70 AND WAS ABLE TO WRAP A 305 X45 TIRE WITH PLENTY OF ROOM (2 INCHES) BETWEEN THE LEAF ADN TIRE. THE OVERALL WIDTH OF THE TIRE IS 12.5 INCHES AND 29 INCHES TALL. I HAD THE RIMS MADE TO 5.5 INCHES OF BACK SPACING IF THAT HELPS. (SEE MEMBERS RIDES .. LAS VEGAS 70 RT NEW SHOES)

I don't know how you got 2" between the tyre and the spring at the rear of the spring (where it is closer) with 5.5 inch backspace Bradgrott? Maybe it is the bigger diameter that does it??

I fitted 295/50/15s on 15x8s with 4.5" backspace and only had a quarter inch gap. I then moved up to 15x10 with 5.5 backspace and the same tire was hard up against the spring!

Now if I had selected a 4.5" backspace on that 10" wide wheel (same as the 8") I would have had about a 0.75 inch or maybe more clearence at the spring but the edge of the tire would have been flush with the outer edge of the bodywork and as I wanted my tire to go up inside the wheel well I decided against that.

The MP spring re-location kit would have ment cutting up the chassis of a numbers matching R/T. So I didn't want to do that either.

My solution was to use offset spring hangers. These give you just under an inch more space under there. That was enough to give me a half inch or more gap between my raised white letters and the edge of the spring at the rear.

The spring hangers were a LOT less hassle to fit as they are almost a bolt-in deal. The only fab work was re-locating the spring perches on the axle and re-locating the hole for the front spring mount as I was using A-body front spring hangers because these allow the use of stock length springs.

With the offset spring hangers, do I need to get a special aftermarket spring - like the SS upgrades? I ask, because I noticed in another thread, you mentioned re-arcing the original spring being much cheaper than replacing them. Also, if I do want to replace them, I should order them from ESPO. Did you use ‘ESPO springs and things’ with your offset hangers? I'm throwing 275 60's under my challenger and love when the rear tucks up inside - do you have any suggestions as to figuring out what the ride hieght would be with a particular spring, as I don't want to buy some - throw them on, with tires - get load on them - and realize I would like them a half inch lower / or higher.


If I understand correctly, if I stick with A-body front hangers, I can use my stock springs (as stock springs are longer)? Longer than aftermarket and SS springs?

Thought I'd ask because I'm not the best with this type of stuff. I'm learning though! One project at a time

You should be able to get 275/60/15 meats under there without moving the springs as long as you are careful with your wheel offset and only use an 8 inch wide wheel or something near.

The ESPO springs should give you a stock ride height and stock spring length. They will ask you for the exact model of your car and give you a spring to suit.

I had my springs custom made here in the UK because I wanted them 30% stiffer (sounds expensive but was still cheaper than importing new from the USA) and it took me a month to calculate the spec. It is MUCH more complicated than I thought when I started. Even then I got the arch camber wrong and had to take them back to get them adjusted.

I don't know what the current state of play is with the MP offset hangers. I don't even know if you can still get them?

But when I did mine they only made offset hangers for use with Super Stock springs.
Now SS springs are the same length as a-body springs which is a few inches shorter than e-body in the front section. So when you use SS springs on a Challenger you have to also use an extended front spring mount.

So MP only made an e-body offset front spring mount that was longer for the SS springs which it assumed you would be using.

However I wanted to use a stock length e-body spring so to get around this I used an a-body front mount instead. Only the mounting hole for the spring bushing is in the wrong place so you have to weld it up and re-drill in the correct place. Use the e-body REAR offset hangers though.

Thank you Dave - you answered all my questions. much appreciated!