2 days ago in News
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I've been following info about the 03-07 Crown Vic front suspension swap because I have a need to replace the front suspension in my 1977 Plymouth Roadrunner. That's a Volare gents. Now, it's been common practice to swap the Volare torsion bar front suspension into Ford trucks for some years now, however, from a performance standpoint, it's pretty lame. Adequate would best describe that set up.
So I ask myself, "Why can't I do that with my Volare?". Several problems come to mind. Track width for one (60.5" for the Volare vs. 67.5" for the Crown Vic). I may be actually able to work with that utilizing fender flares from the Volare\Aspen Super Coupes. But, the biggest hangup is the mounting of the lower A arm on the Crown Vic IFS. It shoots WAY back. On the stock Vic, the frame bows outboard and the A arm bolts to the INSIDE of it. With Ford truck frames, they don't swoop downward too much and the Ford guys make a bracket to bolt to the UNDERSIDE. The Volare frame swoops downward so if I tried to install the Vic IFS, the A arms would foul it. I hope you can see the pic. Top is the stock Volare setup. Bottom is the Crown Vic IFS in a vintage Ford truck:
So, using my limited knowledge of front suspensions, I'll have to ask. Can the Crown Vic IFS be installed in the reverse direction with no ill effects on handling? That is, with the A arms pointing towards the front and using the power rack from a rear steer setup?
Any ideas? That would solve the frame fouling issue I'd have.
It's real nice looking piece...
I know the F-M-J front end leaves a bit to be desired, but you might want to contact Firm Feel Inc. out in Vancouver, WA. They did run an E-Production Aspen in the '90's. They make custom torsion bars for the straight bar cars now. I don't know if they've done any for the bent bar cars.
Another option would be the Reilly Motorsports Inc. "AlterKtion" bolt in front end kit for the F-M-J cars. It's a coil over kit with rack & pinion, custom K-member, etc. Not cheap but supposed to be a nice piece. I know the guys that were the prototype for the drag version of the kit. It's in their Super Coupe. I can follow-up with them to see how they like it.
The only thing I can think to do for the Vicky front end would be to have some custom lower control arms fabricated for it, but even then the front track width is still going to be out there.
Oh, check your Runner for rot in the frame rails where the Vicky control arms are interfering. I had a '76 Volare coupe that rotted there on the driver's side.
The immediate concern I would have in reverse-mounting the CV IFS would be the caster angle...
Hat's off for doing a Volare Roadrunner. Back in the early 80's, my sister had a 76 Volare Roadrunner. 318, Orange exterior, white interior, buckets seats, factory FM/CB! I would like one with a modern Hemi.
Thanks everyone for the inputs. From the info I've gotten over the last few days, it seems that reversing the CV front suspension isn't a very good idea. I know about the Firmfeel parts for the F body, but my goal is to eliminate the torsion bars altogether. Another option I've been told about is a crossemember kit from Industrial Chassis to mount a Dakota pickup suspension and steering rack. The track width on that is a lot closer to the Volare. The price seems a bit better as well.
I didn't know about that Industrial Chassis kit. That looks interesting as does the price.
I suspect the track width is close to the same as the Volare. I have an '88 Dippy parts car here and my trusty '96 Dakota 4x4 if you need some measurements. I also have access to a '89 Shelby Dakota for some measurements if needed.
i couldn't tell from the picture but I'm guessing they are using the '87-90 5-lug rotors. I can't see a whole lot of demand for the Dak 6x4.5" pattern on other cars or trucks.
Rob_Mopar wrote: I didn't know about that Industrial Chassis kit. That looks interesting as does the price. I suspect the track width is close to the same as the Volare. I have an '88 Dippy parts car here and my trusty '96 Dakota 4x4 if you need some measurements. I also have access to a '89 Shelby Dakota for some measurements if needed. i couldn't tell from the picture but I'm guessing they are using the '87-90 5-lug rotors. I can't see a whole lot of demand for the Dak 6x4.5" pattern on other cars or trucks. -Rob
Well thank you Rob, I actually CAN use some measurements. If you can get a tape on the Dak, what is the inside to inside distance between the frame rails at the crossmember and the outside to outside distance as well. I've got ideas...
I'm also looking at an IRS T-Bird transplant. Hey, F body's aren't really worth a whole lot....
The Alterktion kit runs around 5K for the F body while the Industrial Chassis kit can be out the door for $2700. Cheaper if you source your own parts. Just weld it in. I like that option.
I probably won't get a chance to take the measurements until this weekend. I can get them off my Dak, but I think there is a difference in the front crossmember between the 4x4 & 4x2's.
I talked to my friend with the Shelby Dak. She said no problem for taking measurements off it, but i don't know if I can get over there this weekend.
There's a guy on one of the Mopar mailing lists I'm on that's swapping a T-bird IRS into his '66 Dart. He has some info on that here: 66 Dart IRS I'm not sure but he might be on this board too. If he is I'm sure he'll chime in.
I just measured my Dak. I measured the from the bottom of the frame below the front upper control arm mounts. Inside frame to frame is 28". Outside frame to frame is 34".
On the 4x4's like mine, the crossmember is the front axle assembly. I suspect the 2WD version has the crossmember attached in that location.
Let me know if you need any more measurements. I think I can get access to my friend's Shelby Dak next weekend.
Another option you might look into, the one I'm going with on my '40 IH, is the Ford Aerostar front end. It's hard to describe just how it's set-up, but if you see one in person you'll immediately understand why it's so easily swapable.
Well, I've actually come across another option that I like better. Something came up on my radar screen that REALLY got my attention. That is, the drop out IFS from a 93-04 Lexus SC300\400. It's a REAL nice looking piece and it's got a hair over 34" between the frame rails. Just like the F-body. It can use HUGE Turbo Supra brakes and it bolts to the frame. F body front track width is listed as 60.0". SC300\400 is listed as 59.8"
Thinkin' out loud....
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