Hi all!

I don't know this is the proper section of this forum because i just have registered myself.

I have a 306 with XU7JP engine. I was planning to change the engine to an XU9J4Z, but next year here in my country (Hungary) the technical examination rules will change, they will check the engine code each time, and there is no legal way to change the engine. But the law makes me able to change engine if the engine code's 3 first character matches. So my idea was to get an XU7JP4 block (because that has is 16 valve cylinder head, and the bore diameter is 83mm, as in the XU9J4Z) and put the XU9J4Z crankshaft, rods, pistons, cylinder head, and all main parts, so technically build an XU9 engine in a XU7 bock.

My question would be: is my plan possible without any very difficult modification or should i forget it?

This would be a very nice solution for my problem, because the first 3 characters won't change, nobody will know about the upgrade, so my insurance will stay low too.

Thanks for the answers in advance!

Yes the blocks are all basically the same, Silly point why not just swap engine code's as most are rivited on anyway.

Thanks for the answer!

You mean just cut out the part of the block with the engine code on it and put it in the other block?
They check this very strickly here, if they see any sign of this "cheat" then they punish me very bad.. :\
When i bought the car they made very high quality macro photos of the engine number and code, and they will make more at the next exam, if they see i was messing with it that will be s*cks.

Anybody else?

Doesn't anybody can tell me for sure why can or can't i build the XU9 engine in a 16 valve XU7 block?

You can....

thx, i hope i can do that soon. hard to get here both engines :\