Height Difference - Hotchkis Leafs

[Road_Runner]

I would have gone with the III if I had known that the II is no stiffer that it is, but, I am going to shim the valve in the power steering pump and reduce the pressure so it no big deal.  As it is, it is light years ahead of where I started.

If you look at the pics of the front frame rails, you will see that anything I did to the car was useless until I fixed the frame  http://www.vortexbuicks-etc.com/Challengerrebuild.htm

Nice read, you've been through it haven't you!  The one shot that shows how the car sits with the new springs & T-bars looks really good, I like the way its sits too.  I'm going to have to think about the Hotchkis rear springs vs. the Mopar XHDs which I may go with for now and see how it handles once everything is on.  Like yours mine started out with no sway bars & light springs so what I've already got to put on it should be light years better than stock.

Later, Jim

[Strawdawg]

When I look at the pictures in my books, none of them seem to sit as high in the back as many I see here.  After almost 40 years, it is hard to know what has been done or altered on these cars.

[kielbasa]

will you be runing offset leaf hangers and shackles? if so, the dr. diff front hanger has two positions (just like the hotchkis) and that way you could run the springs you already have picked out and slightly lower the rear.
Both the hotchkis and dr diff front hangers lower hole position is the same dimension as stock, and the upper hole is probably an inch or so  higher in the bracket (which would lower the car).
I have to assume you'll be running poly bushings - you'll be in for another unscheduled mini project there also.
the poly stuff is narrower, so you'll need to have a lathe nearby to shorten the bushings while doing the install.
and if using offset front hanger, you need to lengthen those bushings (or use stock ones once they are removed and separated from the original rubber) and grind one side of the bushing flange for clearance (you'll see what i mean once you get that far).
Just bothers me that these high priced "engineered" kits really have some installation shortcomings and these guys don't tell you about them until after the fact.

[Strawdawg]

must be a later change for the Hotchkis hangers to have two holes as they still don't show it on the site, or in the instructions that I can find.

I had no difficulty in installing mine and the instructions were very good, imo.  It must be a car to car thing.

[Road_Runner]

will you be runing offset leaf hangers and shackles? if so, the dr. diff front hanger has two positions (just like the hotchkis) and that way you could run the springs you already have picked out and slightly lower the rear.
Both the hotchkis and dr diff front hangers lower hole position is the same dimension as stock, and the upper hole is probably an inch or so  higher in the bracket (which would lower the car).
I have to assume you'll be running poly bushings - you'll be in for another unscheduled mini project there also.
the poly stuff is narrower, so you'll need to have a lathe nearby to shorten the bushings while doing the install.
and if using offset front hanger, you need to lengthen those bushings (or use stock ones once they are removed and separated from the original rubber) and grind one side of the bushing flange for clearance (you'll see what i mean once you get that far).
Just bothers me that these high priced "engineered" kits really have some installation shortcomings and these guys don't tell you about them until after the fact.

Actually, I am thinking seriously about the Dr Diff Offset kit and that's a good point about being able to adjust height of the xhd springs with their front hanger.  I'd really like to jump on the Hotchkis kit, but I'm struggling justifying it based on how much of this I already have.  I hadn't heard about the issues with the poly bushings, which brand / combination were you installing?  May try to avoid it unless its the case with all poly busings...

Thanks, Jim

[kielbasa]

The Hothkis springs would give a way softer ride (i think, at least compared to my 4 1/2 leafs vs the Hotchkis 2 1/2), and better handling. And if that's what you're after I would go for it (not to mention they already have the front bushing (rubber, stock dimension) pressed in).
The bushing thing is no big deal if you have a lathe (heck, you could probably just leave everything alone and it would bolt up), I just want to minimize slop. Maybe I'm too picky. Although there was at least .100" clearance between shackles and the poly bushings.
I used PST bushings, but the Hotchkis poly bushings shared the same dimension (rear). The PST metal bushing for the front hanger is too short, either reuse the stock ones or make new ones.
The dr diff kit is made to use rubber bushings. Point is, pay attention when you begin putting the stuff together.
But if you are going to be just cruising around, I think you'd be surprised how well the stock stuff with decent shocks, tires and poly bushings will handle.

[Road_Runner]

But if you are going to be just cruising around, I think you'd be surprised how well the stock stuff with decent shocks, tires and poly bushings will handle.

That's just it, I'd like to think I could drive the car at a track day or two, or even just some late night spirited driving, so I don't want to give up too much to a system like Hotchkis.  Plus, if I don't get it handling pretty decently that's going to leave me wanting another car to cover that so in the long run it would be way cheaper if I could get what I want handling wise out of the Barracuda.  I've already bought a bunch of stuff, but before I go any further I really need to decide if after putting all this stuff on I'm still going to want the Hotchkis or similar setup and then I've just wasted more $$ & time.  Right now I could probably get most of my money back if I resell the individual stock stuff as its all in really good shape should I decide to go with a better setup now.  Just got to decide.

 Thanks for the feedback, Jim

[72bluNblu]

I run XHD's on my car in the stock front eye bolt position with 26.1" tall tires. At the top of the wheel arch from concrete through the center of the axle my car sits at 24 1/2", which is about as low as I want to go on the street. I have it set with a 1/4" rake from front to back, not fond of the tail dragger look that you see with a lot of the factory pictures from back in the day.

Hotchkis lists the spring rate on their springs at 160 lbs/in. Now, HP2 would be the guy to ask but I believe the XHD's are around 140 lbs/in. The interesting part about that is the T/A cars were actually set up with 120 lb/in spring rates in the back, which is actually less than the stock springs were. So, higher rates may not be exactly what you want, especially if you're running a rear sway bar.

The Hotchkis springs are lighter though, they're set up with fewer leafs and a different leaf arrangement too, so its not just about comparing spring rates. But, a set of XHD's will set you back a lot less than the Hotchkis springs, and for a street driven car I'm not so sure you'd notice a ton of difference.

[Road_Runner]

But, a set of XHD's will set you back a lot less than the Hotchkis springs, and for a street driven car I'm not so sure you'd notice a ton of difference.

No doubt you're right about this.  I think I'm overthinking this (something I'm known for!) and will just pick up a set of the xhd's, put on what I have, maybe upgrade to Bilstein shocks instead of the Edelbrocks and go from there.  Its interesting how much lower your car sits with XHD's and tires that are only 1" less radius than my 28" 275/60's, mine sits at 27" to the wheel well opening (measured straight up through the center cap of the wheel).  Almost confirms a suspician of mine that the original owner put on heavier rear leafs to tow her boat with (you can still see where the hitch was attached to the car). 

Later, Jim

[72bluNblu]

No doubt you're right about this.  I think I'm overthinking this (something I'm known for!) and will just pick up a set of the xhd's, put on what I have, maybe upgrade to Bilstein shocks instead of the Edelbrocks and go from there.  Its interesting how much lower your car sits with XHD's and tires that are only 1" less radius than my 28" 275/60's, mine sits at 27" to the wheel well opening (measured straight up through the center cap of the wheel).  Almost confirms a suspician of mine that the original owner put on heavier rear leafs to tow her boat with (you can still see where the hitch was attached to the car). 

Later, Jim

Tow a boat?! 

You'll notice the better shocks, that's one of the things I've got on my list. Replace my KYB's with a set of bilstein's. 27" to the wheel arch is HIGH. When I had SS springs on the back in the "lowered" eye bolt location my car sat about 1" higher than it does now. So, even in the stock position with SS springs and my old 26.5" tires my car would have sat at about 26.5". Your tires account for the rest, but those springs have got some serious arch. Basically equivalent to SS springs, although if they're stock length I wouldn't be surprised if the spring rate is even higher.  With XHD's and Bilstein's I think you'll have a much nicer ride. Not to mention better handling! I think the Hotchkis rear sway bar is probably a much better investment than the springs...

[Strawdawg]

For some reason, I thought the XHD springs were also supposed to be about 160#, but the Hotchkis springs provide a very compliant ride when coupled with the Bilsteins.  I would not call it soft, but it is not "jigglely"  on rough surfaces...much of that has to be the shocks, of course.  It has a very controlled feel to the ride even with the cheap tires currently on the car.  It feels like a modern performance car to me which speaks well of the combination.  My experience is that when a car begins to feel "stiff", it only handles well on very smooth surfaces but tends to dance when the surface is irregular.

[Strawdawg]

Some interesting posts in this thread particularly by Tom Quad, HP2, and DQHemi  http://www.cuda-challenger.com/cc/index.php?topic=32717.30

I see HP2 says XHD are around 140 and the Superstockers are about 160

[HP2]

Hi Guys.

Yes, general rule of thumb is XHD springs are 140#, SS start at 160# and Oval track units are 120#.  I hadn't ever heard anything about the Hotchkis rates, but they are an example of how significantly leafs can be altered to acheive performance. Don't forget Cal-Trak offers mono leafs in selectable rates up to 200#, so there is more going on that just leaf count and arch. Leaf springs are actually a fairly complex device and real good competition quality, custom  springs will run you many hundreds of dollars each. Leaf width and height, length, eye construction, taper, point shape, interliners, and a number of other factors all come in to play when leafs enter in to the "ultimate" range. Also consider what type of track time you'll spend with yoru car as a more compliant road race spring doesn't tend to do 5000 rpm drag launches very well and using your car on both venues may require adding some sort of traction device as well. In general though, off the shelf offerings from any of the mentioned suppliers while do the job for most of us, so I'd say set your car up in a way that looks and/or performs the way you want. If your happy with your set  up, even if it isn't ultimate, you'll enjoy the car more. If you ever start pushing your activities to where you require more performance, then its a whole 'nuther ball game and you can re-evaluate then.

Road Runner, theres nothing wrong with overthinking a project. That certainly will give you insight and information you might not otherwise consider. However, sometime you have to eventually pull the trigger on a system. For you, since you have so many other pieces of the suspension, you can certainly set it up with what you have and decide how or when you step up portions. The is one nice thing about the Hotchkis parts, they can be added selectively. Similarly, the Hotchkis parts are also desinged to delivery more linear performance as you push the handling envelope further. For basic cruising, you probably won't notice a huge inprovement, for casual track days, you might notice some improvement, but when you really start laying in to it, the predictability and repeatability of the Hotchkis parts will really shine.

[Road_Runner]

Road Runner, theres nothing wrong with overthinking a project. That certainly will give you insight and information you might not otherwise consider. However, sometime you have to eventually pull the trigger on a system. For you, since you have so many other pieces of the suspension, you can certainly set it up with what you have and decide how or when you step up portions. The is one nice thing about the Hotchkis parts, they can be added selectively. Similarly, the Hotchkis parts are also desinged to delivery more linear performance as you push the handling envelope further. For basic cruising, you probably won't notice a huge inprovement, for casual track days, you might notice some improvement, but when you really start laying in to it, the predictability and repeatability of the Hotchkis parts will really shine.

Yeah, I decided not to overspend on the Hotchkis kit at least for now, and am even going to take a closer look at the springs I have to see if I might stay with them because I really like the way the car sits.  Plus I plan on going with the 1" rear offset & B Body rear so I can lower it 1" if I want to with that setup which might be perfect (for me).  So my next $$ may go to the 1" relocation kit & Bilstein shocks, put on the other pieces I have and go driving.

Thanks, Jim

[Strawdawg]

The Hotchkis springs come with new hardware which is not included with bare springs, normally.  Buying when on sale also helps or with the Summit bux as someone mentioned.