Would the 944 engine from an ST2 be a straight swap for an existing 900ss? If so, would it run ok on the stock 900ss carbs? Would such an upgrade make a sizeable difference to insurance?
There's others that have done this. I have a Frankenstein engine with ST2 cases and 900SS internals. The engine will drop right in. Why not keep the injection system from the ST? Performance would increase so insurance may be altered. I had to do an insurance report for my SS due to all the mods.
Yes, were you hoping it was an easy way to get a 944 upgrade? The plumbing and rad ext make it a bit of a hassle to use. You can use the barrels, pistons and take out the better cams (for better lift) which will give u 944 capacity. You have to alter the water/oil pathways a little on the barrels iirc.
Cooling aside you'd need to either use the injection from the ST2 or modify it to use carbs. Problem I forsee would be the ignition pickup which is different, although you maybe able to fit the SS type ignition pickups to an ST2; the mounting points are there but flywheel is different - might be interchangeable? IMO, a lot of work/hassle/expense so easier to swap barrels/pistons or bore/replate the 900, you could then (probably) use ST2 pistons or get some High Comps from JE or other supplier. On my Monster build I bought an ST2 engine as a cam donor and can see that many parts are interchangeable. Whilst I got rid of most of the ST2 engine, I've still got a few parts left over including the Pistons, if they're any use to you you're welcome to collect them.
