Although, to be honest and fair, the Ford GT's engine is located in the rear-ish so the T-bars aren't necessarily fighting with much. I'm still a T-bar and leaf spring advocate.
Best Coilover IFS for '71 duster?
- Thread starter Mopar Nate
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Although, to be honest and fair, the Ford GT's engine is located in the rear-ish so the T-bars aren't necessarily fighting with much. I'm still a T-bar and leaf spring advocate.
consulier
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Agree 100%, my Gen III swap and header fitment would have been much easier without t bars.
I'd just like to see a competitive Mopar coil over car show up at a PT event so I can see how they compare. The closest car to date would have to be the purple Challenger that is in Hot Rod this month. Unfortunately that car is not one of the bolt-on kits.
Until somebody puts together a competitive car and actively campaigns it against the current crop of actively campaigned t bar cars, the argument that coil overs are better is a non-issue. Packaging... they win. Other than that, there are no results for comparison.
You can't even compare that. It isn't setup at all like a traditional leaf rear.
Kevin. You really need to go back and read what I wrote. I said ALL of the fast cars. Chevy. Ford. And mopar. I feel like I have had the car that showed up at more events on the east coast than any mopar yet. Period. And people will back that up that were there. My car isn't worth near as much as 50 percent of the cars there, it is carbed, sh@! Tires. And I still smoke most of them. It is sad that shop built high end cars have taken over pro-touring.
Yeah, but they run coil-overs because that's what they're chassis and suspension system is designed for (a vertical spring and shock). If you saw the last Hot Rod Garage (the Roadkill show), Ridetech put a coil-over suspension into an El Camino. The whole setup was a bolt-on ordeal. Easy! Going coilovers on a Mopar is almost like telling a Chevy guy to go to torsion bars. The coilover conversion is done more frequently with mopars because it's easier to convert from torsion bars to coilovers than from coilovers to torsion bar. It definitely has its benefits, I won't argue there, but as far as handling I'm not sure it's much better than the Torsion Bar system.
replicaracer43
Grumpy Old Man
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NASCAR stock cars in the late 60s ran in the 160 MPH range, and by 1970 ran 200 MPH, and that was with the torsion bar/leaf spring suspension system, at 3800+ lbs, on bias ply tires......Go ahead and argue that that's not comparable, but those cars were built with they factory style suspension design, just optimized. If a guy bolts in a coilover kit in his mopar and goes faster, its because he couldn't PROPERLY tune his suspension. SPACE AROUND the torsion bars is the ONLY real disadvantage.
Correct....space is ONE of the reasons some of us use them.
To review....
Another benefit (reason) is exhaust SELECTION. For instance, when I added my Hemi in my A body, instead of building custom exhaust....I installed off the shelf B/E body TTi headers. While TTi now offers header specially for rack /cool over conversions, many benefit from utilizing B/E headers on the A body.
Another reason is as stated earlier in the thread, coil covers are the only choice in a rack conversion because without moving the LCA pivot point, geometry will not work.
To review....
Another benefit (reason) is exhaust SELECTION. For instance, when I added my Hemi in my A body, instead of building custom exhaust....I installed off the shelf B/E body TTi headers. While TTi now offers header specially for rack /cool over conversions, many benefit from utilizing B/E headers on the A body.
Another reason is as stated earlier in the thread, coil covers are the only choice in a rack conversion because without moving the LCA pivot point, geometry will not work.
Marshalearp
HemiGTS
Well, you are correct in that the geometry won't work with an "end takeoff" r & p. It does, however, work fine with a "mid takeoff" r & p because you can precisely duplicate the stock inner tie rod pivot point positions. In fact, you can optimize the pivot points to bring bump steer very close to zero. With ride height as base line, I have .007" toe-in at full compression, and .009" at full rebound.
Old Man Mopar
Righteous Dude
A lot of people autocrossing and roadracing seem to favor big stiff torsion bars which
produce a harsh ride and seem to lower the tires ability to maintain the contact patch.
I was always of the opinion that you should run very soft torsion bars but an enormous
sway bar and shocks with a lot of damping. When you dive into a corner it should suck
the whole front end down with no leaning, possibly producing a desired camber change
as well.........or maybe it just sucks?
Please enlighten me.
produce a harsh ride and seem to lower the tires ability to maintain the contact patch.
I was always of the opinion that you should run very soft torsion bars but an enormous
sway bar and shocks with a lot of damping. When you dive into a corner it should suck
the whole front end down with no leaning, possibly producing a desired camber change
as well.........or maybe it just sucks?
Please enlighten me.
I would love to SEE it....the inner to inner tie rod measurement while important was not the difficult part (for me). The challenge is getting the correct height of the rack to fit the factory geometry. The rack would pretty much have to travel thru the block / oil pan....unless a drag link was incorporated (exactly what I did 20 years ago on my very first one that utilized torsion bars)
show us what you got.....I'm willing to learn.
The high end shocks that are now available (Hotchkis, Bilstein, QA1, etc) make the ride with larger torsion bars very manageable. The ride quality in my Duster is very similar to my g/f's 2013 Mustang with premium suspension. Sure, its stiffer than an old musclecar, but that's a joke.
The problem with the "small torsion bars big sway bars" approach is that you're not going to find sway bars large enough to run "small" torsion bars and still but able to handle that well unless you make them yourself. I have 1.12" torsion bars AND the largest sway bars that Hellwig sells on my Duster, including a 7/8" rear sway bar intended for E-bodies. The car stays pretty flat, but there is still some body roll if I crank it around hard enough.
Sure, on a street car I think 1.03" bars, good shocks and large sway bars will provide a little nicer ride than my car with 1.12" torsion bars. And tires are a really huge part of that equation. If you're running BFG T/A's on 14" or 15" rims going to larger torsion bars than that won't do you any good anyway, you don't have enough grip to make them work. But if you're running modern compound 275/295's like I am, even the 1.12" t-bars will have their work cut out for them if you really put things to the task because the tires are going to grip a lot longer and put significantly larger loads on the suspension. If you start running race compounds in something as wide as a 275, even the 1.12" bars might be too light for certain courses.
Marshalearp
HemiGTS
I'll take a couple of pictures for you. Have to get the car up in the air to show it properly of course. I'm leaving for Phoenix in a couple of days so it might have to wait until I get back. The rack is a Total Control Products piece. You can see it on their website. The rack uses a separate bolt on drag link, and mine has tabs that locate the inner pivots above the actual rack, if that makes any sense. That means that the rack mounts below the pan, but the inner pivots are actually located upward just the same as the stock Mopar drag link does. These racks were designed by Chris Alston Chassis people specifically for early Mustangs, but it's possible to make them work for rear steer/torsion bar applications. If you look on their site; look at the model they designate for big block application, and you'll quickly see what I mean about the pivot tabs. It's a very heavy duty piece; much more so than any OEM type rack, and also has the correct ratio to work with the long steering knuckle arms that are found on the old style worm and sector systems like our cars. On my Dart it's only 3 turns lock to lock and I have a slightly smaller turning circle than stock. I will post some pictures though.
Marshalearp
HemiGTS
That's exactly what I have on my Dart. I have .870 bars with the Hotchkis 1 1/2" front sway bar. Handles and rides very well, I think. Of course, I don't compete with the car, but I do quite a bit of "spirited" driving, and it seems to have very little body roll. It does tend to understeer somewhat, but that just keeps me from getting too nuts. I've played with the idea of a small rear bar, but then I think maybe I should just leave well enough alone. Lol
Very cool....I love innovation.
Do you use factory spindles?.... if so, what was done for steering arms / ackerman?
Marshalearp
HemiGTS
Yes. Factory spindles, LCAs, etc. Ackerman is not upset because the outer pivot points/ball joints/steering arms are stock, and are not disturbed. These racks attach directly to the frame rails and the housing spans the full width between the rails. The pinion housing is at the extreme left(driver's side) and is right up tight to the frame, which means little interference with headers etc. I don't want to give anyone the impression that this is a bolt-in, because it isn't. Unless the person has a good working knowledge of steering/suspension geometry, and significant facilities for machining and fabrication, they should stick to stock, or go for your system, which by the way, I consider to be the best such system available, for a variety of reasons. I didn't install r & p for the sake of having it. I was installing a 6.1 crate motor on the factory K member and didn't like the engine placement that these kits give. I wanted to keep the 6.1 accessory drive with the a/c and alternator mounted down low, and the TTI type "kits" don't allow for that. So I cleaned everything off the stock K member, moved the crank centerline 9/16" toward the center of the engine bay and fabricated a set of spool type mounts. That cleared up the space on the passenger side but eliminated any possibility of using stock type steering, hence the r & p.
DR HEMI
Man on a Mission
I really wish that the proponents of torsion bars, although most assuredly well intentioned,
would not "rush forth" and try to save us from ourselves every time someone utters the words
"coil-over conversion".
Fact: Most everybody I know that has a coil-over conversion did not make the change
to improve the steering, handling or get a weight savings (although those things seem
to be a very pleasant side-effect). They made the change for engine and exhaust access;
many times to fit a powerplant that God did not originally intend to occupy that space.
Period.
would not "rush forth" and try to save us from ourselves every time someone utters the words
"coil-over conversion".
Fact: Most everybody I know that has a coil-over conversion did not make the change
to improve the steering, handling or get a weight savings (although those things seem
to be a very pleasant side-effect). They made the change for engine and exhaust access;
many times to fit a powerplant that God did not originally intend to occupy that space.
Period.
Old Man Mopar
Righteous Dude
Those are sweet and Hi-Tech looking but the power rack conversion alone is over $2300.00 shipped and then
you have to adapt it to your Mopar. You will have still all of the rest of the stock suspension and steering parts.
Not necessarily a bad thing as long as your engine swap can tolerate the space for torsion bars. If you then
need to add coil over shocks and tubular control arms, of course the price climbs.
Marshalearp
HemiGTS
Rear steer. As I mentioned previously, these pieces were designed specifically for Ford not Mopar. They don't sell anything for non-Fords.
Marshalearp
HemiGTS
Well, that's very true. That is why I said that I didn't want anyone to think this was a bolt-in deal, and certainly not for the average person. Nor am I advocating this design for anyone else, for that matter. I wanted to retain the stock suspension and components and would have kept some form of stock style steering box ( probably 16-1 manual ) but could not because of the engine positioning. Money was not the issue. If I had wanted a coil over type suspension I would have bought one, but I wanted to retain as much of the original musclecar soul as was possible, and that most definitely included torsion bars and leaf springs.
Old Man Mopar
Righteous Dude
I applaud your effort. A relatively high price to pay but sometimes not having to work
around that stock steering box is "priceless".
Marshalearp
HemiGTS
Thanks for the advice, but I was not trying to "save" anybody from anything, least of all coil over suspensions. Personally, I have never much cared what anyone else does, or doesn't do, in any category. This conversation began as a response to Denny saying that in order to use a rear steer r & p, the LCA pivot would have to be moved because it's impossible to make the geometry work. I simply responded that while that is true of OEM end take-off R & P, that mid take-off R & P works perfectly with the existing suspension geometry. Period.
Marshalearp
HemiGTS
For myself, I have always immensely enjoyed the engineering part of hot rodding. I look at the large picture, decide what I want to end up with, examine the feasibility of the exercise and make it happen Capn'. Actually, in this case I also wanted manual steering, plus I got an absolutely screaming deal, so it wasn't that bad; but one way or the other it was going to happen.. and it did. And I couldn't be happier with the results. It's also kind of fun to see the look on people's faces when they notice there is no steering box. The R & P is pretty hard to see without getting on the ground and squeezing under the car. I get a chuckle out of guys trying to figure out how this guy drives with no steering box. Kind of perverse, I know.
DR HEMI
Man on a Mission
That comment was in no way aimed in your direction but rather at those in general
who ceaselessly expound on the superiority of torsion bar suspensions at the slightest
suggestion that one may be considering undertaking a coil over conversion.
You have commited no such trespass and in fact I am enjoing reading about your innovation.
Marshalearp
HemiGTS
I agree completely. I've never been able to understand the seemingly prevalent concept that
"what I have is absolutely the last word, and everybody should do/have what I did or have".
If I was building a drag car or any type of race car I would very likely have some sort of coil over deal in it. But I drive a muscle car because that's what I grew up in, and it's a nostalgia thing I suppose. All I know is I really enjoy the car. I wanted a GTS like I had 100 years ago when I was a youngster. Except I also wanted a modern hemi, 5 speed etc. etc. BUT, to me the most important thing was that it retain that "feel". It wouldn't mean anything to someone born in the last 30 years or so because they never had that "connection". I can fully appreciate the advantages of the coil over type suspension and I really enjoy the innovative engineering that a guy like Denny has put into his product; it truly is great. But at the same time I love the torsion bar/leaf spring setup for it's old time feel and simplicity. There's plenty of room for both.
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