Fiat Twin Cam engines

[AndrewKB]

The other post on the problems of SU carbs, spacers, and air filters on BMC B-Series engines got me thinking ...

I have, for some time, been considering an engine swop to a Fiat Twin Cam but I'm now told that parts for these engines and gearboxes are becoming very difficult to source and I'd appreciate anyone's experience on this issue. I'm not talking about the odd thing that wears out but rather whole units like gearboxes (us triallers subject our cars to rather hard lives) or complete cylinder heads.

Any recent experience would be very much appreciated.

[amalgamated users from prior forum]

Re: Fiat Twin Cam engines

Message originally posted by: Tony Wylde
Ready supply of parts on E-bay, I have been running a twin cam in a Leader and I have had no problems getting parts. All I do is buy a spare as and when the price is right. In fact there is an engine and box complete whith ancilliaries at the moment for about ?150 There is also an engine with most parts for ?30 and I have just bought a spare engine Box and prop for ?50. So parts are not that hard to come by.

[artrider50]

Re: Fiat Twin Cam engines

Excuse my ignorance for the following, but...
There's lots of posts about putting in this engine and that, and I've always wondered exactly what is involved in such a swap??

e.g. swapping my B series for a Fiat twin-cam; what else would be needed apart fron the engine? Do new engine mounts need to be welded on and how do you know where to put them?! Gearbox? Prop-shaft? Clutch? Brakes? Rear-axle/diff? Wheels even?

Perhaps there's not a simple answer, but if all the above is involved would it not be easier to sell the car and start from scratch with a new kit?

[amalgamated users from prior forum]

Re: Fiat Twin Cam engines

Message originally posted by: Stefan Carlton
Swopping from Marina B to Alfa twin cam will involve new engine mounts (maybe not new location however - not sure on that one), gearbox cross brace & possibly a new prop (dependent on the location of the engine). You might need to put a different clutch system in (not sure if Alfa is hydralic & if the Marina master has the correct bore/stroke). The rest should be able to remain the same assuming the Marlin radiator (15"*15" 3 core) is enough to cool the engine.

The only time you need to change the rear-axle is if you start to put the output torque up - IIRC the Marina axle copes with ~110bhp (and since peak bhp is at roughly the convergence point, a similar level of torque). You could of course choose to change the rear axle for something with a LSD if you so desired to improve handling.

[peter.oldland]

Re: Fiat Twin Cam engines

I swapped from a 1300 to Fiat 2ltr twincam.

Get the latest possible from a 131 or 132, with 5speed box - this has an extension that puts the gearlever in an ideal position and also has a rubber doughnut coupling that 1. fits the Marina propshaft and, 2. takes the shock out of the drive shafts. Mine came from a 1984 132 Argenta. The carb and exhaust are on the left and right respectively, meaning that you don't need to change the steering linkage.

I had my chevette rad rebuilt with 3 rows and have no overheating problems. I should have had a thermostatic switch fitted at the same time but forgot and have since added one from Premier Wiring into the top hose - it works perfectly.

The engine mounts came from YKC who have the pattern although if you can bend steel, copying mine would suffice. I cut off all the Marina mounts and welded the new ones in. The position was set by the overall length of prop, box & engine and it fits very neatly. I used Mondeo engine mounting rubbers. I also had a support beam made up at my local smithy that runs from chassis rail to rail, meaning that the unit is well supported and not dependent on the tunnel for suppport.

Conversion from hydraulic clutch to cable was easy, as was the accelerator cable.

Mine has a Bosch black box electronic ignition and this was a doddle to set up.

Service parts are easy to get (Italian Car Parts in Manchester are friendly and useful) although I have not yet tried to get overhauled or reconditioned engine bits as the one I found had a very low mileage.

The exhaust manifold is quite nice 4 into 2 so this stayed but I had the downpipes y-piece and long pipe (I wanted a rear exhaust) made up at JP in Macclesfield. The standard Marlin box is fitted although my next job will be to have JP make me a silencer up that makes a nicer noise!

The reults are terrific, loads of low down grunt but still able to rev up to 7000+ if you want (or dare).

I try to get to as many shows and meets as possible so anybody is welcome to chat to me about this installation - might go to Bromsgrove on Sunday for the run out and would be available in the afternoon for chatting.

[ggrum]

Re: Fiat Twin Cam engines

Some time ago I replaced my 1300 'A' series engine with a 2 litre Alfa twin cam. I made up new engine mounting brackets to fit on the existing 1300 mounting points on the chassis rails but had to cut off the optional 1800 mounting point on the nearside to clear the oil filter (not sure if all kits were fitted with both sets of engine mounts for both engine options - mine is a 1983 vintage). Alfa Romeo Guilla rubber engine mounts were used as they are quite compact and fitted well into the space available.

My engine is mated to a Ford Sierra gearbox via an adaptor plate and I used the YKC gearbox mounting cross member. The old (Viva or Chevette?) radiator was re-cored to give greater cooling capacity and fitted with a thermo-static switch to operate a front mounted fan and I have had no problems at all with overheating.

The standard Marinal steering column arrangement fouled the Dellorto side draft carbs so I fitted the steering column from a Ford Capri (which is quite long)and routed it through a large hole in the brake pedal box between the brake and the clutch. The secondary shaft then runs underneath the carbs. This has the additional advantage of putting the steering wheel at a more conventional angle instead of being virtually 'flat'. There was a whole lot of other stuff that needed doing as well, most of which I have since forgotten but is documented somewhere in the garage. If anyone is interested in more detail let me know and I'll try and oblige.

[jon_cox]

Re: Fiat Twin Cam engines

Peter,
I have a fiat twin cam in my roadster that uses the cable operated clutch. My problem is that the clutch is extremely heavy and requires a significant amount of effort to push the pedal down. Do you have the same problem?
Hugh has converted his to hydraulic but this would require a lot of work to do to mine ie. engine out job.
How did you convert yours? Any tips!!!

[peter.oldland]

Re: Fiat Twin Cam engines

Jon,
My clutch pedal was from a Maestro i think and i used the diagram in the Haynes manual scaled up to work out the length required for the top lever. I use a 131 cable. Yes it is heavy compared with say a modern small car but has never been a problem on journeys. It certainly doesn't have the 1" play at the pedal recommended in Haynes but i think i must have got the top lever just right as the clutch bites at a very natural point. I put a complete new assembly in when rebuilding to allow for things being a bit tighter than recommended and it all seems to have bedded in ok in the 3000 miles i've done since. Can somebody explain why a hydraulic clutch would be better? If you've got to move the clutch operating lever X mm, and the clutch pedal is shorter than intended, the same amount of effort must be required whatever the connecting method - energy cannot be created nor destroyed i understood.

[jon_cox]

Re: Fiat Twin Cam engines

Peter,
Can you please tell me the length of the top lever you have used. What total cable displacement does this give you? My clutch seems to need 48mm total cable movement to work correctly. Is this similar to yours?

[peter.oldland]

Re: Fiat Twin Cam engines

Jon,
Top lever is 59mm - will advise what that equates to in cable/operating lever movement when I've got a helper.