toplessFC3Sman

I'm planning on picking up a running engine from a wrecked S2 to rebuild and hold onto as a spare for my manual S2, but it seems that engines from automatic trans cars are more common and cheaper. I know the auto S2 engines (in the US anyway) are all 6 ports, and I think they were still limited to 7500 RPM for the trans, but are there any hardware differences between the engines (especially the core components), injectors, MOPs etc?

Thank you!

toplessFC3Sman

From what I can tell, digging through parts catalogs, the short block, intake, exhaust, fuel and ignition systems are all the same for S2's. If I find anything different, I'll post it up here.

spectre6000

I'm no authority, but my recollection is that they are the same for S2s. Might be some minor top end differences, like you mentioned, but all the same where it counts.

toplessFC3Sman

I haven't gotten very far in taking the automatic-equipped engine apart, but so far, the notable differences externally are:

• The automatic engine does not have the VDI actuator on the lower intake manifold - there is just a blank plate externally, but the rotating valve mechanism within the manifold looks the same. It's just cast as a single piece with the plate so that it cannot spin. the LIM casting looks identical and has all the provisions to allow a functioning VDI valve to spin - its just the bolts on the plate that are holding it fixed.
• The VDI solenoid and wiring still exists on the oil fill neck in the row of 3 solenoids, but the outlet port is capped. I guess this was all done to minimize the # of parts variations for the UIM, oil fil neck, wiring harness etc?
• Of course the auto engine has the separate counterweight and flex-plate instead of the flywheel

toplessFC3Sman

I've gotten the whole engine torn down, and while I haven't done a side-by-side comparison of all the parts (the manual parts I have are currently assembled as an engine in the car), nothing else looked different besides the three things listed above.

TeamRX8

iTrader: (25)

here’s a picture of one




and yes, interchangeable with the 6-port VDI, same intake manifold otherwise.

it varies from the S1 LIM in that the APV barrels are different, to accommodate the APV position sensors that the S1 doesn’t have. The entire thing bolts on to the S1 engine, but the APV barrels aren’t interchangeable between the two LIMs.
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