405 Sti Xu10j2c, upgrading 16 valve from an Xu10j4r??

bl4ck clio · Unread post by **bl4ck clio** » 06 Aug 2009, 18:23

hi guys, i have a 405 sti xu10j2c automatic, and just wanting a small modification to the engine, I was thinking about upgrading my engine with a 16 valve head from an 406 2.0 (xu10j4r), anyone tried this before?? and what work is required??
can this mod done only swap the head? or much more like piston, ecu...etc is different so this mod hard to be done?

because I think if it can be done, the cost is cheap.

thanks in advance for ur help .

Best Regard

Jay.

Unread post by **CitroJim** » 07 Aug 2009, 17:23

It may be possible as I understand the blocks are substantially the same and the drillings might be in place for the additional cambelt idlers necessary.

However, having said that, you face major problems with determining that the compression ratio will remain in limits and the old 8V injection may not suit the 16V head. You may have to use different pistons.

For the marginal benefits the head swap might bring, surely it would be better to do a wholesale transplant of an XU10J4R engine and management. I'm sure this would be the far better route in the long-run.