Differences in US 4.7 and Euro 4.7
03-24-2007 | 10:30 PM
#6
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Originally Posted by DJC-928S
Are there any significant differences with th 4.7 US and the 4.7 Euro aside from compression?
So, how is compression raised over the US model, with different pistons, crank or both?
In PET, is the Euro covered by ROW models?
Also, is there any major difference in wiring diagrams? So far, everything I've worked on follows the same year US diagram. Are Euro diagrams available?
So, how is compression raised over the US model, with different pistons, crank or both?
In PET, is the Euro covered by ROW models?
Also, is there any major difference in wiring diagrams? So far, everything I've worked on follows the same year US diagram. Are Euro diagrams available?
Pistons, heads.
For the most part ROW = Euro. There are some rare country exceptions (Japan, Switzerland...).
Yes. Yes. They're all in the FWSM.
03-24-2007 | 11:33 PM
#7
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Basically everything above the block, and from '84-'86, the distributor caps were a pair of 944 4 cylinder parts connected by a sewing machine belt.
This last because this 4.7 actually used the injection and ignition systems, with chip changes, from the 5.0 32 valve engines that debuted in 1985. Basically, an '85 US 32 valve has the same computers as an '85 S2 16 valve. The programming is different is all. I discovered in 2003 that I'd been driving my S2 around with a US 32 valve box. I changed the chip and there was a definite difference. One year ago I obtained a correct, perfectly functioning original S2 box for $150; When I changed them out there was no difference.
N!
This last because this 4.7 actually used the injection and ignition systems, with chip changes, from the 5.0 32 valve engines that debuted in 1985. Basically, an '85 US 32 valve has the same computers as an '85 S2 16 valve. The programming is different is all. I discovered in 2003 that I'd been driving my S2 around with a US 32 valve box. I changed the chip and there was a definite difference. One year ago I obtained a correct, perfectly functioning original S2 box for $150; When I changed them out there was no difference.
N!
Last edited by Normy; 03-25-2007 at 10:54 AM.
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03-25-2007 | 01:11 AM
#8
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Normy, the distributors are not from a 944. There is at least one major hardware difference between an ROW/Euro LH 2.2 and a US LH 2.2 in addition to the software programing.
03-25-2007 | 01:38 AM
#10
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Originally Posted by FlyingDog
Normy, the distributors are not from a 944. There is at least one major hardware difference between an ROW/Euro LH 2.2 and a US LH 2.2 in addition to the software programing.
03-25-2007 | 08:47 AM
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Bores are same but there are three different tolerance groups. Its not good idea to change pistons without checking they will actually fit correctly. Also wrist pins are same.
Sametimes people are saying LH2.2 and EZF were developed for '85-86 US model but being first used in '84-86 ROW S. ROW cars came with it year before US models. More likely they were developed for ROW models and applied to US 32V engine when it was done.
Took apart '86 ROW M28/45 32V engine yesterday. Its very rare to see these engines in here. Pistons in it seem to have larger pits that US engine pics show. Think this confirms quoted 9.3:1 CR. This engine had suffered 2/6 conrod bearing failure years ago in Germany and had been in VW dealer backroom since then. What kind of idiot at factory designed bolts which were used to mount valve covers?
Managed to destroy 5 or 6 of them.
Sametimes people are saying LH2.2 and EZF were developed for '85-86 US model but being first used in '84-86 ROW S. ROW cars came with it year before US models. More likely they were developed for ROW models and applied to US 32V engine when it was done.
Took apart '86 ROW M28/45 32V engine yesterday. Its very rare to see these engines in here. Pistons in it seem to have larger pits that US engine pics show. Think this confirms quoted 9.3:1 CR. This engine had suffered 2/6 conrod bearing failure years ago in Germany and had been in VW dealer backroom since then. What kind of idiot at factory designed bolts which were used to mount valve covers?
Managed to destroy 5 or 6 of them.
03-25-2007 | 08:06 PM
#12
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Originally Posted by DJC-928S
I'm thinking of using a spare Euro engine for supercharging by lowering the compression with US pistons so I can push higher boost.
You may have to cut in valve reliefs.
03-26-2007 | 08:27 AM
#14
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[QUOTE=Vilhuer]Took apart '86 ROW M28/45 32V engine yesterday. Its very rare to see these engines in here. Pistons in it seem to have larger pits that US engine pics show. Think this confirms quoted 9.3:1 CR.[QUOTE]
Interesting! I have a US 32V engine, and I have measured the compression in that engine to be 9,5:1. Is the pit larger or the valve cut-outs? Here is a picture of my piston: http://www.flickr.com/photos/2196736...7594052999722/
What are you going to do with this engine? Are the cylinder walls thicker than normal?
Interesting! I have a US 32V engine, and I have measured the compression in that engine to be 9,5:1. Is the pit larger or the valve cut-outs? Here is a picture of my piston: http://www.flickr.com/photos/2196736...7594052999722/
What are you going to do with this engine? Are the cylinder walls thicker than normal?
03-26-2007 | 10:56 AM
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Ian, you have very interesting pics up.
I'll take pics of the pistons later today. Looking at your picture I would say pit is same and valve cut-outs are visibly larger. If so, very smart move from factory to make them less vulnerable for valve damage.
Crank is probably straght but would need undersize bearings as many bearings had suffered after those two rod bearing went. Conrod bearing pieces killed all 8 piston skirts also. Sadly they are now only good for astrays. Rods might be useful but aren't very good. Heads are usable with some welding at valve cover mounting points. Don't have any use for them though. Cams look fine and could end up in GTS, or I use GT set which need some work and keep these as spares.
Block walls are in same 116mm range like many other blocks I have seen. Luckily bores are centered better than others I have access to. If nothing new shows up after block is cleaned, it will end up into GTS with 104mm bore. At first need to clean up this mess.
Bores look ok but more likely would need machining to oversize to make them usable. It is as good candidate for large pistons as I have ever seen.
I'll take pics of the pistons later today. Looking at your picture I would say pit is same and valve cut-outs are visibly larger. If so, very smart move from factory to make them less vulnerable for valve damage.
Crank is probably straght but would need undersize bearings as many bearings had suffered after those two rod bearing went. Conrod bearing pieces killed all 8 piston skirts also. Sadly they are now only good for astrays. Rods might be useful but aren't very good. Heads are usable with some welding at valve cover mounting points. Don't have any use for them though. Cams look fine and could end up in GTS, or I use GT set which need some work and keep these as spares.
Block walls are in same 116mm range like many other blocks I have seen. Luckily bores are centered better than others I have access to. If nothing new shows up after block is cleaned, it will end up into GTS with 104mm bore. At first need to clean up this mess.
Bores look ok but more likely would need machining to oversize to make them usable. It is as good candidate for large pistons as I have ever seen.