1972 Firenza "chassis swap"

personally I prefer the non blended scoops that you originally mocked up.

I always think that blended scoops just look like someone forgot to fill the gap, unless they are like Quattro S1's and the whole height.

Thanks for all the thoughts/input on the side scoops. I don't think they'd ruin the look of the car, but I couldn't stop thinking how much I prefer the car without them. In addition, the more I worked out the details, the more negatives became apparent (loss of boot, loss of easy exhaust routing, cost, weight, heat transfer into cabin etc).

I was chatting to my old man in the week, when a simple alternative materialised. In this instance my dad was an accidental genius; when he sarcastically said that I could put the rad where the intercooler is going, I quickly realised that the joke was actually the solution...

Intercoolers don't (usually) have fans, and (with my extensions to the Impreza inner wings) there's loads of space where the top mount intercooler is meant to go....the solution; reverese the original Impreza setup by putting the rad on top of the engine, being fed by the scoop...why we didn't think of it first I've not a clue.

Having done some google based sanity checking, I'm convinced it'll work fine; I did actually find a few examples where others have done the same (modified off roaders).

Yesterday I measured up for the custom radiator and intercooler; to do this I had to put the engine back in:


Here's the original problem...no room for a conventional radiator/fan arrangement, but an intercooler will slot in nicely:


Look at all the lovely room here though (the gearbox sits here, but is low in the car):


The plan is to cut into the rear bulkhead a little (tapered back into the engine bay under the rad); by doing this, I'll actually have slightly more radiator capacity than the uprated one that came with the donor. In this pic the red box represents the radiator:


So, the side scoops are off the table, and we can crack on (getting quotes on the radiator/intercooler next week)!

Long overdue update.. Stuff has been done (all seat mounting done for example), to a point where we need to start getting ready for sand blasting prior to paint.

We needed to access the underside (welding, repair, strip, and paint), but we initially couldn’t figure out how to do it. Simply rolling it onto its side was a no go (due to the arches and sills sticking out), and the design of the front and rear meant that rotisserie attachment was difficult. The solution was a custom roll-over jig/frame; the frame picks up the crossmember mounting points, but provides a fantastic amount of access:

85CDC6AB-1F0A-4F44-8625-1F13DE5FD8FB by firenza boxer, on Flickr

048FE583-4006-4D0D-9601-9B8B428EBA3E by firenza boxer, on Flickr

430C805D-B02D-4E3E-A46C-AF7FE76DF10F by firenza boxer, on Flickr

Things to do underneath before sand blasting:
- seam weld bottom lip of the sills
- finish welding around arches (now we can access it)
- repair the crushed chassis legs (visible in pics), caused by some dopey previous owner who should have stepped away from the trolley jack
- strip off factory rubbery undercoating (that blasting wouldn’t touch)

Nothing too interesting, but a quick update to the build log...

I’ve eventually managed to remove all of the rubberised undercoat (the best meathod was using a knotted wire angle grinder ‘disk’); no nasty surprises were lurking underneath. I’ve actually been shocked at the total lack of rust on the impreza; the shell was a sti, therefore an early J import.

Fixing the damage caused (not by us) from incorrect jacking has been done; I didn’t take pictures of the process, but you can tell what I did in the picture below with the un-dressed welds (I remove the crushed floor stiffeners, beat them straight off the car, then plug welded them back on):





One of the seat brackets (on each side) was welded straight to the floor. The impreza floor pan is made from reasonably thin steel, therefore I decided to plate the area around the mounting point. Thick steel plates were hammered to fit before being fully welded on; the plug welds in the plate pick up on the bracket welds for extra strength:





And finally, the bottom flange of the sills were carefully seam welded:



There’s a little more welding to do inside the rear wheel arches, but it’s not far from being ready for the sand blaster.

Wouldn't it be easier to have two rads and a link pipe?

Small update on a few bits:

Boot floor done (with mounting points in the top-hat for the two exhausts:


Mounting for the iPad sorted (had to devise a way that wouldn’t put too much pressure on it). The real iPad that will be going in has a black surround not white; for building the dash, buying a fake (display) iPad, has been invaluable though:




And worked out how to secure the dash vents; these are modified AUDI A1 dash vents, that interestingly work in the same way as the original viva fresh-air vents:

Nice Project - any progress since June?

Picture of the finished dash (hole for the dials will be cut once I’ve got the bezel machined)