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Title: How to tell a VX head? Post by: droptop on August 18, 2012, 01:28:52 PM I've just bought a small shed load of Beta parts and one of the items is a 2.0 head the seller thinks is off a VX. Now, I understand these have bigger valves than the standard one, but as I don't have a standard one off an engine to compare it to, can anyone tell me the VX valve diameters and if it would be a good upgrade for my carburetted '78 Spyder which I plan to fit twin 40's on now that I finally have the correct manifold? Thanks folks. Title: Re: How to tell a VX head? Post by: HFStuart on August 18, 2012, 05:49:28 PM The VX head has 43.5mm inlets and 36mm exhausts instead of the standard 41.8mm and 36mm.
Yes it would be a good addition to your Spider (Guess what mines got?) but I think you need to plug a few of the bolt holes around the manifold to get it to accept the normal bolt patterns. If it's come with cams then the exhaust also has rather less lift than a standard one. Title: Re: How to tell a VX head? Post by: peteracs on August 18, 2012, 06:06:23 PM Hi All
I seem to remember a recent thread where I think it was Eric who commented on which cams make sense to use with carb config, I think the VX ones are not that useful on the carb/ie engines from memory. Peter Title: Re: How to tell a VX head? Post by: rossocorsa on August 18, 2012, 08:33:12 PM Simply swap over the cams with carriers to the vx head
Title: Re: How to tell a VX head? Post by: droptop on August 18, 2012, 08:37:32 PM I was figuring the cams would have an unsuitable profile but I still don't know how to tell if it is a VX head without taking mine off and with only 36K on my engine, I'm not inclined to twat about with it for the sake of finding out ???
Title: Re: How to tell a VX head? Post by: rossocorsa on August 18, 2012, 09:40:05 PM something tells me that the small gains may not be worth the effort unless you are taking the head off anyway
Title: Re: How to tell a VX head? Post by: droptop on August 19, 2012, 09:57:37 AM That's the sort of information I need.
I bow to your superior knowledge and save myself a winter of hardship. Now I no longer care which engine it came off and I'm just going to sell it on. Thanks. Title: Re: How to tell a VX head? Post by: rossocorsa on August 19, 2012, 10:09:58 AM I'd keep it you never know when you may want it or you might change your mind
Title: Re: How to tell a VX head? Post by: HFStuart on August 19, 2012, 10:02:54 PM I was figuring the cams would have an unsuitable profile but I still don't know how to tell if it is a VX head without taking mine off and with only 36K on my engine, I'm not inclined to twat about with it for the sake of finding out ??? IS the head you bought in the load of parts off the engine? If it is just measure the inlet valves - that wil tell you. Title: Re: How to tell a VX head? Post by: monte on August 20, 2012, 04:22:42 PM The VX cylinder head is part no. 5881825 and all other 2000cc heads are 81191533
Should be a marking somewhere on the head ,I expect ,if it doesnt carry either of these numbers ,it may well be a off a 1600cc This all leads me to wonder is the bottom half of the VX engine the same as the rest , or does it have different pistons , conrods ,or crankshaft ? Title: Re: How to tell a VX head? Post by: WestonE on August 20, 2012, 04:47:34 PM Monte
The bottom end of the VX engine has no cut out for a manual fuel pump. It has different pistons i.e. lower compression and thicker top ring land. It has bigger crank oil drillings and tougher bearing material on the big ends. The rods are the same. The oil pump has a reserve chamber built in. Also VX head gaskets were the superior Astradur thermal resin gaskets as early TC head gaskets had a high failure rate even before pressure charging. I hope this helps in some way, but this is all covered in GCs Books particularly the first one. Eric Title: Re: How to tell a VX head? Post by: 75coupe on August 21, 2012, 01:42:29 PM Hi there,
VX casting number is 593188. I have a ported one on my 2 l coupe with twin 45DCOE, GC 3A cams etc. now into 8000rpm territory.....It has 2 sets if holes on inlet side, but all you have to do is move studs to fit carbs. s(http://img.tapatalk.com/3ce74e6b-818a-d21a.jpg)(http://img.tapatalk.com/3ce74e6b-81ad-0a5e.jpg) Title: Re: How to tell a VX head? Post by: 75coupe on August 21, 2012, 01:43:43 PM Sorry casting number us 5936188, left 3 out !!
Title: Re: How to tell a VX head? Post by: monte on August 21, 2012, 04:19:01 PM Interesting conundrum , maybe someone can shed some light on it ,the VX cylinder head belonging to 75coupe clearly is part no 5936188, yet my parts microfis , dated 12-1984 only shows 5881825 for the VX head , I have a VX too , so I have since had a look , and yes it is the same as that of 75coupe 5936188, so just wonder was there a later revision ? or maybe just an error in the preparation of the microfis ??
Title: Re: How to tell a VX head? Post by: droptop on September 01, 2012, 06:00:40 PM Monte, we're talking Lancia here so the reasoning is anyone's guess!
I suppose at the end of the day I should be celebrating the fact that mine runs at all considering the circumstances of my acquisition of it and my blind stumbling into the whole thing, never mind my ambition to "improve" the poor thing! Title: Re: How to tell a VX head? Post by: rossocorsa on September 01, 2012, 08:17:57 PM You can never rely on the part numbers on castings because the basic casting may have been made into more than one finished product
Title: Re: How to tell a VX head? Post by: monte on September 01, 2012, 08:35:27 PM Droptop, true none of it makes any sense , we could all be in shinny new cars , but what fun is that !!
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