Gti 6/ Xu 7

[craig_007 1]

Hi all,

 

I've just bought 83.5mm high compression Omega pistons(From maxirallye) I'm about to build a spare engine for my 205.

 

I've checked previous threads and would just like to clarify that I can infact get away with this !!

 

I'm going to look for a XU7 bottom end,Remove the crank,pistons and liners etc and fit my 1.9 8v crank with the MI high compression pistons and standard MI rods,I then intend mating a GTI 6 head to this (cams are still undecided)

 

Is this as easy as it sounds ??

 

What timing belt cover would I be looking at using here ?? Would it be a complete XU7 set up or the XU10 ??

 

Can I use my already baffled MI sump from the engine I'm using just now ??

 

Sorry if this has been done to death,Just looking for some confirmation before I start spending more cash !!

 

Cheers Craig

[Anthony 1,003]

Remember the GTi-6 head has a 4cc smaller chamber size than an Mi16 or S16 head, and hence combined with high compression Mi pistons will give very high compression.

 

Baffled sump will fit just fine, although the XU7 bottom end with have a trapdoor baffled sump as standard.

 

As far as I know, you can use the complete XU7 cambelt cover setup.

[welshpug 1,661]

you would use the complete XU7 setup regarding the timing belts and tensioners, and belt cover and engine mountings.

 

as Anthony mentioned the chamber is slightly smaller, so you'd have a higher compression ratio, though IIRC you can get a slightly thicker headgasket to compensate if the resulting ratio would cause issues.

Edited October 19, 2009 by welshpug

[Saveit 0]

As far as i understand the 1.9 8v crank journal size is different to mi16 which means you cant use the mi conrods on the 8v crank. Could someone please confirm?

[welshpug 1,661]

both are 50mm, its 1.6+1.8 crank+rods that are 45mm.

[Saveit 0]

Ahh okay.

[tony perks 1]

The Mi rods are narrower at the Little end though, and have bronze bearings for fully floating (circlip retained pistons)

[Batfink 201]

The mi16 pistons I think have bigger valve cutouts but you are probably going to have to do a dry build and see if you have any piston/valve clearance issues.