Sizing up hat car candidates

I read in a thread some advice on the most critical dimensions when body swapping a car but I can't find it now. Besides the wheelbase and track width I seem to remember something like the distance from the front wheel to the driver's seat and the spacing of the front seats from the trans tunnel were considered important to match closely to make for a good swap.

Any advice from the guys who've already built one? I'd want to keep the dash and body together so probably look at splicing together part way down the firewall. Good/bad idea? Guessing it might make the HVAC a bit trickier, but then I may not fit any anyway.

Height of the firewall/ cowl and distance from front wheel center to firewall/ windshield frame

Firewall is critical because firewall/floor/tunnel are all interrelated.

Front wheels to steering wheel length as they pertain to the location of the firewall and windshield. The hat car(more of a visor car) we built required adding length to the fenders behind the front wheels which isn't the most fun place to do body work.

In reply to Racingsnake :

I have a little bit of experience in this game, and suspect that you are recalling something I said at some point.

So yes, front axle to front seats and seat side-to-side distance will ensure that you fit in the driving space of the "hat". 

Cowl height also comes into play since if you cant see over the window of the "hat" raising the seat and the steering wheel is not trivial. You move one item and it sets off a chain reaction. A good example of a hat car that does not work is the early mustang on the newer mustang chassis. Because of the cowl height limitations, the sill dont match up and the results are not ideal.

If you are good with fender flares, then track width is not a huge deal. 

Anything more than 2" of wheelbase difference and you will have to get creative with solutions.

What are you planning to build?

In reply to NOHOME :

Thanks for all the replies. A friend has a '59 Ranchero and is thinking of putting it on an 80s LTD frame. Since the Ranchero also has rusty floors that need replacing I think it might work quite well to leave the LTD floor on the frame and then weld the Ranchero body to it rather than redoing the floors and having to make all the body mounts as well.

Does the Ranchero have a frame?

The 59 Chero is body-on-frame

In reply to Racingsnake :

If the measurements work out, then it sounds like a good plan. The whole point of the chassis swap is to install a much better car under the skin of the classic car body. As such, you want to keep as much of the modern design and ergonomics as possible. Ideally, the donor chassis stays running during the whole deal.

I spend a LOT of time considering where to cut. To this end I actually dismantled the donor chassis by drilling out spotwelds so that I could reclaim a decision if need be.

What you maybe dont want is to be doing two restorations projects along the way. 1980 was a ways back, and the donor chassis is probably going to need some refreshing.  You want the donor chassis to be a head start, not just another task if that makes sense or else it might be just as easy to fix the original car.

This guy on YouTube does a tone of chassis swaps and does them fast and cheap, might be worth a look.

In reply to NOHOME :

I'll check those videos out. The LTD is a low mileage running, driving car whereas the Ranchero is rusty, worn out sitting for years so it does make some sense. I would probably just engine swap it and put discs on the front if it was mine but my friend wants to use everything off the LTD and I think doing the frame & floorpan swap would be the most effective way to do that.

In reply to Racingsnake :

When I did the Molvo, the big payoff was that the interior and firewall  with all of it's components took a time jump from the 50's to the 90's.  Everything inside the cabin bolts together like a 1996 Miata with the factory ergonimics intact.  Seats, Carpet, Gauges,Steering entire vehicle wiring and even seat belts are already done for you.

The one thing that a chassis swap is not is a time or $$$ saver over doing a restoration. You will also end up with something that is not going to have any real value as a collector car going forward, so its pretty much sunk $$$.