Westfield Posted December 30, 2002 Share Posted December 30, 2002 I have been looking around for a big valve head for my crossflow and have been offered one from a 1600 XR2 Fiesta. Is this the same head and therefore interchangeable? Any advantages or disadvantages if it will fit? Also, is the block the same as a 711M and can it be used in a Caterham? Tony Link to comment Share on other sites More sharing options...
cdg Posted December 30, 2002 Share Posted December 30, 2002 Heads are identical and interchangeable. Blocks are outwardly similar, and can be made to fit the RWD application but the water and oil pumps are different, and the crank is shorter overall. I wouldn't bother with the block... Chris. Link to comment Share on other sites More sharing options...
Rory Posted December 31, 2002 Share Posted December 31, 2002 MKI XR2 head uses the same valve sizes as the 711M GT engine. The head can be used on any 'Kent'. The block differs in that it has an extra web above the timing cover to facilitate an extra engine mount for the FWD application. This web will not be a problem. The oil pump is different, in that the filter is rotated up the way as, in the FWD application, the NS drive shaft goes through the filter position in the RWD pump. Your biggest issue is the water pump and timing chain cover/crank pulley position and also the crank/flywheel. The water pump has its inlet on the exhaust side of the block rather than the inlet side on the RWD 711M, they are however inter changable. The timing cover and crank 'nose' are shorter to fit in the Fiesta engine bay. This means that the 'common' bolt for the cover/pump must have a spacer fitted if the RWD pump is used. Also if you want to fit Duplex chains, they don't fit in the cover. Next up is the sump. The Fiesta has the deep part at the front of the engine. Not suitable for a 7. The RWD sumps do not fit as the front timing cover is a different depth. The RWD Timing cover can be fitted to get over this however but a one of the bolts doesn't line up, meaning a wee compromise with a drill and a big washer. As mentioned in an earlier post, the crank is different. There is no needle bearing for the primary shaft in the box, and the ring gear on the flywheel is the wrong way round for the type of starter used in the RWD application (these can of course both be changed). ---john--- Link to comment Share on other sites More sharing options...
Nigel Riches Posted December 31, 2002 Share Posted December 31, 2002 John you've obviously done the homework on this subject, but with regards to the sump pan, could some suitable baffles be installed to stop the dreaded oil surge, with someone determined enough to go to all the trouble of sourcing and refurbing a suitable engine a bit of a fiddle with the sump wouldn't be much of a problem. Best regards for the New Year, just4hr12ms to go, Nigel. Link to comment Share on other sites More sharing options...
Westfield Posted December 31, 2002 Author Share Posted December 31, 2002 Thanks for the comprehensive replies! The main thing for the moment is the head. I have been offered one off a XR2 that the owner tells me has been well modified. I will be looking at it next week, anything to watch out for before I part with the cash? I am looking to build a 145BHP engine. I already have a block although it’s already at 83.5 mm and has some serious score marks. I am looking to go to 84mm and then have it tested. My alternative if fails looks to be an XR2 block as these are plentiful in my local scrap yard! Thanks Tony Link to comment Share on other sites More sharing options...
cdg Posted December 31, 2002 Share Posted December 31, 2002 Tony, I don't think you'll have a problem boring to 84mm, but I don't know where you'd find an 84mm x/flow piston. As far as I know the next usual size up from 83.5 is 85mm. If you ever want to go Sprinting the 84mm bore size would take you (usually) into the over 1700 unlimited class, which is not a good thing! If you're looking for a block you could try; Anderson Racing Engines 01761 472 524 Jason Lepley Motorsport 01623 443796 Richard Parkin 01773 591281 Yorkshire Rally Spares can't remember number Airedale Race Products "" "" Or check the ads in the back of Motorsport News. They'll all be able to send one to you. Chris. Link to comment Share on other sites More sharing options...
Rory Posted December 31, 2002 Share Posted December 31, 2002 Tony, if its only a block you need the XR2 one (771M) will work fine. Use the crank, timing cover, water pump and sump fronm your existing block (711M I presume) and all of the the problems I've mentioned above will go away (except for one timing cover bolt not lining up. ---john--- Link to comment Share on other sites More sharing options...
Graham Perry Posted December 31, 2002 Share Posted December 31, 2002 I am pretty sure accralite do an 84mm piston Link to comment Share on other sites More sharing options...
Westfield Posted December 31, 2002 Author Share Posted December 31, 2002 The plan is to use Accrilite 84mm pistons which are available from various suppliers. The cost is quite high though at £490 plus the cost of the rebore. Still, this along with a refresh of the other parts, shells, timing chain etc should give me an engine that should last for a fair while. Just hoping now that the block will bore to 84mm successfully, fingers crossed! Thanks again Tony Link to comment Share on other sites More sharing options...
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