Xu Engine Blocks

[Batfink 201]

I have no engine anymore as i sold my mi16.

I need to build a new engine so need to start with the block.

It needs to be able to run a 16v head

Which is lightest/strongest both in block strength and piston liners?

mi16?

xu10j4 (1.8xsi)?

other?

 

or does it not really matter?

 

Kev

[welshpug 1,661]

XU10J4 is the iron block bottom end, so no liners.

 

1.8 XS is the alloy XU7, which I believe was the base for the WRC 2.0 turbo engines, though I don't know how modified they were bar 85mm liners and an 88mm stroke.

 

what I have seen with the 1.8 engines is that the bores are usually in good condition.

 

unless you're running boost, I don't think block strength matters, more the condition and choice of components, I've seen many a standard 1.6 crank and rods being run up to 8k in competition!

[Batfink 201]

mistype!

Yeah i meant the xu7 jobbie

 

I know the mi16 has more strengthening ribs than the 8v block so thought it might be useful! There will certainly be no boost but there will be high revs

[welshpug 1,661]

not sure what strengthening bits there are on the 9j4 block, here's a 7jp4 rear view, haven't got a front one yet.

 

 

 

plus point, gti6 head drops straight on with the original timing belt and belt covers, should think it'd go very well with some xu9j4 bottom end components, IIRC from reading up on the differences in all the xu heads it has a slightly smaller chamber volume than the Mi heads which would push the compression up a bit, would just need to check that there's enough clearance @ tdc.

[James_R 3]

The top of the deck is thicker on the XU7 blocks and later XU9 blocks, only the Mi block has the oil spray bars, if you really care about them.

 

Lines wise looks like Mi jobbies, XU7J4's just look like 8v smooth walled items.

 

I'm using a XU7 block now, but bare in mind the mounting is different to the face of the Mi block.

[Batfink 201]

ohh theres an interesting point and a rather fundamental one at that. I'd better go with an mi16 block then as otherwise the solid mounting points wont match whats been done on the chassis.

 

just need a bare block now