'85 Grand Marquis body on '98-'02 frame questions

[Hearsesrock427]

Looking to swap out my '85 Grand Marqs frame (rear driver side rail failed the hammer test) to something better AND more structurally sound come spring. I've heard from various sources that body mounts, bumper brackets, and such will all bolt right up. Only issue I can see are the frame lengths. Were the '98+ Grand Marqs still 2 inches longer at the front like they were on the boxes? What about '98+ Town Car frames vs the box Town Car frames? Or were they all the same after '98?

Also what about rear ends and rear brakes? Would an aero rear end bolt up to a '98-'02 frame? How would all this affect sway bar selections and other suspension parts? (I.E. would I use an addco aero rear sway bar on my aero rear end on the '98-'02 frame or should I use the addco whale sway bar?). Thanks for any help you guys can give.

[Mr Bean]

Why go through all the trouble of a frame swap and not benefit from 2003-2011 suspension and steering upgrades?

To answer your questions, Town Car frame is longer and won't work. Not sure about frames being 2 inches longer in the front.

Aero rear won't bolt up. Mounts are different and Whales have Watts Link. Rear sway bars are same 92-2011. Front bars are 92-02 and 03-11.

[His Royal Ghostliness]

'98-up rear suspension is better design anyways, you want to keep that.

The only 2" frame difference that I'm aware of is with the Towncar and Mark VI that have the extra frame length between the wheels (hence the Lincoln-specific long-tailshaft transmissions). No Grand Marquis specific frame length difference up front that I'm aware of, actually IIRC front fenders swap between GMQs and Crown Vics. Having a box Grand Marquis (yours actually) and a same model year Crown Vic parked side by side I sure as fuck didn't see no length differences up front, one looked exactly like the other...

[GM_Guy]

I think his frame length concerns are for the front and bumper mounting, box cv and gm are different lengths. But he'll need to fabricate bumper mounts anyway so frame length isn't critical. Mr Bean can confirm if the front bumper mounted directly or needed some fab work.

Alex.

[Mr Bean]

I think his frame length concerns are for the front and bumper mounting, box cv and gm are different lengths. But he'll need to fabricate bumper mounts anyway so frame length isn't critical. Mr Bean can confirm if the front bumper mounted directly or needed some fab work.

Alex.

If he uses 92-02 frame the bumpers should mount directly assuming the frame has that 2 inch extension in the front that GMQs have. If not he would have to fab up custom mounts. Should be pretty easy though, just add a couple of inches of pipe to the existing mounts. I recall pantera77 doing comparison of the frames so he should be able to confirm. Assuming it has that extension the 92-02 frame should pretty much plug and play. Very little to no modifications required. 03+ will require modifying rad support and making custom bumper brackets.

[VicCrownVic]

Here's the thread Mr Bean is referring to: http://www.grandmarq.net/vb/showthre...-Frame-Lenghts

[His Royal Ghostliness]

Oh, that, yeah now I remember seeing it, just never registered they are different between GMQs and the CVs. But it seems like I've mostly worked on GMQs, so yeah... lol

[Hearsesrock427]

Alright, that's some excellent info. Thank you all for your help! Will be going '98-'02 route for the '85 this summer, see reasons below.

The only reasons I don't want the '03+ setup are how their steering feels and the additional cost. By far my biggest issue is the steering feel.... got to drive my buddy's '08 CVPI a while back on a fun driving road. Steering is light on center, which is great! But then it gets heavier as you load it up which makes no sense to me and kills the mood. I either want the steering to be light all the time, or have the steering be slightly heavy on center but have it get lighter as you load it up. So unless there's a specific rack and pinion setup for '03+ that matches my needs I don't see a point. A fun car has to feel right, and if its steering feel doesn't match my preferences, it's not worth driving.

There's also the cost issue. My '85 needs a ton of work, and I want to get it completely up to snuff in two years or less. I get ansty if stuff sits on the backburner or takes too long. Now it'd be one thing if I had another fun car to cruise around with while the '85 is under the knife but that's simply not the case. And it's not like the '85 is going to drive like ass when it's done. '98-'02 is still damn good. Especially with the metco watts linkage, metco control arms, addco bars, poly body mounts, gas-a-justs, good set of tires etc. It'll be an improvement over the '89, which is fricken amazing its own right! It dodges deer and errant motorists with the best of em'.

Note to admins... Perhaps we should sticky or merge this thread with posts from the ModBox thread to make a frame swap info thread?

[His Royal Ghostliness]

The reason they make steering light in center and heavy from there on out is stability at high speed - it would be downright dangerous to have the steering feel get progressively lighter as the steering wheel angle increases, it's a perfect recipe for a rollover. The steering boxes (as opposed to rack and pinion) do have a bit stiffer center position yes, but that's to fight steering wheel wander as the wheels follow the 2-tracks in the road surface - and in my experience this trick only works with passenger cars, get enough weight on the front axle (think diesel truck with a snowplow) and the steering will float as much as it pleases, resistance from steering box is completely ignored. In any case, based on your preferences you are best off with a '98-'02 frame setup, it will give you the steering feel you like with better rear suspension and big brakes and discs from the factory. Bonus points if you find one that has things in good shape so it requires little in the service parts replacement area.

[GM_Guy]

That is the vaps function, theres a sensor ring in the column, and along with speed and rpm data it determines how to drive the power steering pump (PWM signal). I dislike it as well, I like my old school turn with your pinky-steer power steering.

Alex.

[gadget73]

I dont care for the pinky steer at all. I have a late CVPI steering box on my car, which is not pinky steer by any stretch. I like it quite fine. My issue with the rack and peanut is the generally dead feel it has. I would like a Watts link or a panhard bar in the back though, the old 4 link setup sucks balls. Its not real practical to retrofit a Watts link on an 86 frame, and quite frankly I'm not overly motivated to swap the frame on the car at this point.

[His Royal Ghostliness]

I actually do want pinky steering, but when you 4000 lbs on the front axle alone there's only so much a steering box can do, lol. Hydro-assist coming in this summer for that, the goal is to end up with feather-light steering wheel feel (which is godsend when you're trying to avoid the "gimme 40 acres and I'll turn this rig around" fun) combined with firmness and control like that of a rack and pinion car. Bonus points for the cylinder also acting like a humongous steering damper so the road surface can no longer grab the wheels and jerk the steering around. A Panther steering box can be ported for that too actually, even tho there's very little place for the cylinder to live in.

[gadget73]

The early power steering systems worked like that. It always seemed like a terribly bad idea to me. If that rotary valve goes flukey the steering just rams whatever direction it feels compelled to do so.

[HiFiMerc]

I love pinky steer. Like it for backing trailers too.

[gadget73]

It honestly scared the hell out of me. A sneeze should not generate a lane change.