Interim cover onto a 1983 3.5

Chedder · Post by **Chedder** » Sat Jul 04, 2009 1:11 pm

Hi Guys, after a bit of advice, I have a 3.5 efi (1983) fitted with duplex timing chain and cam driven dizzy with oil pump, I want to swap to the later interim cover with the crank driven pulley, what is needed to carry out the conversion? Don't need the dizzy drive anymore as running coil packs, just want the better oil flow and pressure.

Chedder

topcatcustom · Post by **topcatcustom** » Sat Jul 04, 2009 5:10 pm

If you don't need the dissy you don't need an interim cover, you should be able to get a later serp front cover without dissy provision for half the price, plus the engine will be about 3" shorter and you can get away with a single serp pulley on the front instead of the big pulley stack that V belt and interim engines have. The water pump is different and spins backwards (part of the belt set up) and you will probably need to make or buy new brackets for the alternator, PAS pump etc, and I think you just need to get the keyway in your crank extended a little which means taking it out- but a pretty easy job.

I think thats about right!

TC

Chedder · Post by **Chedder** » Sat Jul 04, 2009 5:42 pm

Hi, thanks for the reply but I wish it was that simple, Unfortunately I am running a supercharger with all the associated bracketry and pulleys, hence why it would be much easier to use the interim front cover and retain the current set up, but have the better oil pump thats fitted to the later types. So if anyone has successfully completed this mod I would love to know the prolems thay had to overcome.

RoverP6B · Post by **RoverP6B** » Sun Jul 05, 2009 12:36 am

I imagine clearance issues will come into play. What type of car is the engine in?

Ron.

Chedder · Post by **Chedder** » Sun Jul 05, 2009 9:22 am

Engine is in a TVR tasmin, no problems with clearance in front of the engine, need to know if the interim over will fit over a Cloyes duplex timing chain and if the crank key is long enough to drive the oil pump.

RoverP6B · Post by **RoverP6B** » Sun Jul 05, 2009 9:47 am

As it stands then, your crankshaft key is not long enough to drive the oil pump. The interim key slot in the crankshaft is 60mm in length. So you will need to have the slot in your crankshaft machined in order to accept the necessay key to engage the pump.

You may have to fit an interim engine's crankshaft damper too..

Ron.