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seat marbella engine converted to fiat/seat 133 engine, running anti clockwise

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sleurhut:
Hello GMR forum,

I got a Fiat/Seat 133 for daily use. When i got it i did a full service on the engine, drivetrain, brakes and suspension. The car is in pretty nice shape for something that is over 40 years old.

After running it for a while the Original engine lost oil pressure while idling at a trafficlight. Since this event the engine makes a tapping/knocking sound. probably bearing related problems due to oil starvation.

Bought a 133 engine from a vintage Lancia/fiat dealer in the north of the Netherlands. This engine had been sitting for about 20 years in a shipping container. The cilinderwall of the 3e cilinder got rustdamage and the 4e cilinder also got damage. If i want to use this engine it has to be overbored and new piston have to be fitted. A lot of work for a 840cc engine

After searching i found out you can use a 903cc seat Marbella engine for this application but you have to reverse the way the engine runs. A Marbella engine runs Clockwise. An 133 engine runs anti-clockwise.

I bought a very recent Marbella engine from 1998 with a very low milage (kilometers we call it in holland). Got it honed, measured and cleaned.

To change engine rotation i have to change the ignition, camshaft, waterpump and oilpump to counter clockwise turning ones. the blocks are the same.

Despite a lot of searching and measuring before I started the convertion to make sure it would work one thing was forgotten:

Fiat changed the stroke of the crankshaft to increase the number of cc's from 843 to 903cc.

 a 843cc got an 65x63.5 stroke.    The 903CC got an 65x68 stroke.

so the piston travels +/- 4.5mm more in the 903cc compared to the 843cc.'

My question is: can i still use my 133 camshaft? i'm afraid the timing on it wont work with the increased stroke. like it wont run in synth with the inlet and outlet stroke

Does somebody have some info on this or is this done before? how can i overcome this problem or is this not a problem at all?

greetings,

Joost van Beers

olavr:
No problem, use your 133 camshaft. And the distributor together with the drive gears from the 133 will also work in the Marbella block.
The Marbella has a deeper oilpan, use the Marbella oilpump.
If you want to use an alu oilpan from a 850 coupe or spider, the 133 pump is perfect.
Good luck

sleurhut:
just measured the lift heights of both camshafts, they are both a 10mm lift (dont have a micrometer handy out here but with some calipers it should me pretty accurate). thickness of the lobes from the side are the same and the height measured from top to bottom is exactly the same for both cams. but the shape of the lobe is a bit fatter on the marbella cam,

i will make a cam profile sketch and post it here,

if someone has some info on camshafts and which one to use for this engine please comment!

sleurhut:

--- Quote from: olavr on April 12, 2016, 10:32:57 pm ---No problem, use your 133 camshaft. And the distributor together with the drive gears from the 133 will also work in the Marbella block.
The Marbella has a deeper oilpan, use the Marbella oilpump.
If you want to use an alu oilpan from a 850 coupe or spider, the 133 pump is perfect.
Good luck

--- End quote ---

Hello Olavr

so i can use the 843cc camshaft in the 903cc marbella engine? i will use the 903cc (larger stroke) crank, pistons and rods.

will it work with the increased stroke?

sleurhut:
nobody? :(

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