Having discussed the motor, I'm going to deal with some examples of the work that went into this project - the steering wheel & column; and yes those are elastic bands holding the switch gear together in photo 2...
LOVE this thread. Seeing them completely stripped nekid and reassembled with everything buffed out is da best. Big mahalos for sharing this build.
Example two; the interior...seats first. Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login
Example three: refinished wheels and new tires... Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login
MONSTER Weber carb for the BIG block 903... Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login
Question: Have you done anything about the wimpy coarse-splined axles and joints originally fitted to an early 600/Multipla? These are apparently very prone to failure even with less than 30 bhp on tap. I'd sure avoid dragstrip starts with your 903 engine, especially if you're carrying passengers or other extra weight. I was looking in my 600D parts book the other day, and I was surprised to see that non-slotted 12" wheels ARE correct for Multiplas from some point in 1958 onwards. I had thought that all Multiplas were fitted with the slotted wheels - wrong again!
no, reusing original axles. I don't expect to flog the Multipla (as I have other cars for that|) but we'll see what the limitations are and deal with making improvements as issues present -
We are still dealing with little details on this to work around previous decisions. For example: we chose to replace the original 600 engine ( which would have needed a rebuild) with a NOS 903 "crate" motor we found locally with "0" miles. The knock on from this was the choice to rebuild a twin throat Weber to replace the single throat carb of the 600. This left us with a new (hopefully reliable!) engine and a very nice power upgrade. However, we want to keep the appearance as stock as possible and so the effort to reuse the air cleaner housing from the original car. photos show; 2 barrel carb on manifold, original air filter housing, and a series of photos of the process. BTW, we are going to try to re-use the little blue plate that you can see on the original housing. Still a few more days to get it all painted up and installed on the car. Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login
The little blue plate on the air cleaner is available from Fiat Inc for only $8.00. Keep up the good work!
Air cleaner and valve cover, painted and installed. Voltage regulator in place and wired. Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login
Jeff, thanks for the heads up on the sticker. Our car was quite bereft of graphics. Any other stuff I should be looking for in that dept.? BTW, making the 600 cc cleaner work with the 850 carb. was a bit "interesting" Aside from dual throat carb is taller than stock, therefore had to flatten portion of underside to allow clearance. The whole assembly had to be raised by 20mm, to keep filter sitting level to engine and car, thus the elongated washers to secure to manifold. 850 carb is not flat across the top, it angles downward by 15 degrees to right side. We wanted to keep my dual throat air extension sitting plumb and true to air cleaner, therefore added the 12 degree taper to flange where it attaches to carb face. We matched the curve of the new extension to the same radius as the air filter body, rather than just square so that is looked as least ‘frankenstien’ as possible. as you can tell, we REALLY didn't want to use the typical aftermarket solution! .
With the 903cc engine and the original (600cc) rad it seems we are somewhat marginal on cooling: although it's not entirely unexpected. The 903cc had a fairly deep finned aluminum sump and combined with boiled & pressure rad we thought we'd start there to see where we were. The result was slight overheating after about 20 minutes, so not awful, but not going to cut it at Concurso Italiano in Monterey! We are currently considering one or combination of the following: start with replacing 3 core with 4 core and electric fan with better blade design which should be more than adequate. If not, we can an oil cooler and/or an extractor fan on the underside to draw air from the engine compartment. This is probably going to take a couple of weeks...
I had similar problems with a modified 850 spider - years ago now. The solution I went with was an Abarth one- an underfloor radiator that mounted between the fronts of the trailing arms. Here is a version: http://mrfiat.com/italian/fiat/fiat-600/engine/fiat-600-abarth-750-radiator-22-75-x-2-75.html I think others sell them. Conventional wisdom amongst the fiatisti was that more radiator cores etc didn't cut it. After all, Fiat went to all the trouble of moving the engine over by flipping the ring and pinion and reversing the engine rotation to fit a bigger radiator in the 850 c.f. the 600. Anyway, the undercar version worked great for me, and apart from a couple of pipes appearing in the bottom of the engine bay, was invisible. Good luck, Phil
As a former 850 Coupe owner, the 850 cars also had special pans at the bottom of the engine bay to keep warm air from recirculating in the bay. If those pans are missing on an 850, the car is likely to run hot.
Thanks guys, all of the shielding for sealing the engine bay is in place. we have looked at the option of fitting the "Abarth solution" but for the moment want to try some things a bit closer to the original design. It's still an option though...
To keep the engine bay looking stock, you can place an under-car radiator further forward, and tap into the lines that run to the heater. This was my eventual solution on my slightly modified 850 Sedan, after: 1 - switching to a PBS water pump 2 - adding a row to the radiator (thicker core) 3 - converting to electric fan 4 - attempting to reroute the incoming air for better cooling. Each of these solutions prolonged the time until the engine reached heat soak and the cooling system betrayed inadeqaucy. Only adding the extra radiator cooled the 1000cc engine. IF the Multipla flows air like the 850Sedan (IF), then it pulls air in through the rear cover and the fan pushes the air OUT the bottom of the car. I attempted to reverse the airflow and made a "scoop" in front of the radiator, and then set my fan up to exhaust the air from the engine compartment. This did not work. I hung my extra radiator up near the nose, which made plumbing very easy. While I was worried that it would catch debris, the only trouble I've had with it is that on winter days the car runs VERY cool and I don't always have adequate heat. A slide-in-place cover takes care of that, but it isn't as elegant as I would like. I remember buying my radiator from the local radiator shop, and I think the fellow said it was originally a heat exchanger from a Dodge van ?????
thanks Jonathan. We may end up there at the end of the day, but I think we have a good shot at covering off the issue with less extreme measures. Our 903 has a much larger finned aluminum sump so the delta is quite small. And yes, you are correct air from the rear is pushed through the rad and under the car!
First, a quick update on cooling. It seems we have arrive at a solution that involves; electric fan and sealing the opening around the engine/bodywork interface. Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login
applied for "collector plates" last Thursday; here are the photos - page 1 Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login
page 2 - approved in one day. usually takes 4 - 6 weeks! Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login Image Unavailable, Please Login
