260DET Posted February 11, 2010 Share Posted February 11, 2010 The info which follows does not appear anywhere else that I have been able to find, suprising given that we are talking about swapping in a forged crank to replace a cast one and using a higher capacity oil pump involving engines that some would consider obsolete by now. I'm approaching this topic from the view of building a high performance no compramise turbo engine. The short answer is that using a VG30DE/TT ("VG30") crank will result in cam sprocket and timing belt tensioner pulley misalignment, the crank sprocket will sit 7mm further forward. Which means that the cam sprockets and tensioner pulley will have to be spaced 7mm forward. I'm not going to consider accessory alignments here but obviously things like the water pump alignment will be affected. At this time I have not decided whether to proceed but it should be possible to align the cam sprockets by changing the alignment when converting them to be adjustable as to valve timing, which I intended to do anyway. As to hanging the sprockets out a further 7mm that obviously changes the load exerted on the front of the camshaft and its bearings. Now to oil pumps. First of all the VG33 oil pump cannot be used with the VG30 crank, it is narrower front to back so the oil seal does not align with the crank. Will the VG30 oil pumps fit? I say 'pumps' because while the naturally aspirated and TT use different capacity pumps their exterior dimensions are the same. The answer is a qualified 'yes', if you are prepared to do some creative engineering. The oil gallery hole lines up as do all but two of the mounting bolts. The flanges are about 90% good but some building up of the block face is required, liquid metal should do. Plus drilling and tapping two M6 holes in the block. Note that the VG30 pumps use a larger ID pickup tube and the outlet is slightly bigger in ID too. A couple of pics should illustrate what is needed, one pic below shows the two required holes marked with white dots, the other shows an old VG30 pump sitting in place. Quote Link to comment Share on other sites More sharing options...
260DET Posted February 11, 2010 Author Share Posted February 11, 2010 The two pics referred to above, note that the old oil pump gasket is yellow in colour and still in place. The part of the block to be built up with liquid metal or whatever is the rough part surrounding the white dot on the right side. Quote Link to comment Share on other sites More sharing options...
hoov100 Posted February 12, 2010 Share Posted February 12, 2010 To fix the 7mm length issue, couldn't you surface down the oil pump mounting surface on the block? You would maybe have to drill the mounting holes a bit longer to make up for it, but tapping it or helicoiling shouldn't be a problem. I'm giddy as a school girl on prom night, when it comes to vg33's. Quote Link to comment Share on other sites More sharing options...
260DET Posted February 12, 2010 Author Share Posted February 12, 2010 Problem is that the oil pump drive part of the forged crank snout is longer front to back than that of the VG33's. This is to accomodate the wider VG30 oil pump. Come across anyone who has actually done the swap? Yeh I love the design of the single cam VG's, just something about their elegant simplicity. Put together like your ideal woman Quote Link to comment Share on other sites More sharing options...
hoov100 Posted February 12, 2010 Share Posted February 12, 2010 hmm. What about using 7mm spacers on the cam sprockets to align the timing belt correctly? (this is adduming you can use the 33's lower crank sprocket.) (and no, I havent found anyone that has done this, I've heard of numerous vg30 crank/oil pump swaps, but no z32 crank swaps.) Quote Link to comment Share on other sites More sharing options...
260DET Posted February 12, 2010 Author Share Posted February 12, 2010 Yeh the 33's lower sprocket has to be used due to its diameter. Spacers could be used, see my comment in the opening post. Its all doable, will it be reliable though. Quote Link to comment Share on other sites More sharing options...
hoov100 Posted February 12, 2010 Share Posted February 12, 2010 Yeh the 33's lower sprocket has to be used due to its diameter. Spacers could be used, see my comment in the opening post. Its all doable, will it be reliable though. If you do everything correctly and with enough attention to detail, I don't see why it wouldn't be as reliable as if the factory did it, you might run into an issue with stock timing covers as well, but that shouldn't be to hard to fix. Quote Link to comment Share on other sites More sharing options...
260DET Posted February 12, 2010 Author Share Posted February 12, 2010 If the valve gear blows @ 7000rpm on an interference engine then there is going to be catastropic engine damage. These motors are relatively rare and expensive for me so I'm proceeding with caution. Quote Link to comment Share on other sites More sharing options...
hoov100 Posted February 12, 2010 Share Posted February 12, 2010 If the valve gear blows @ 7000rpm on an interference engine then there is going to be catastropic engine damage. These motors are relatively rare and expensive for me so I'm proceeding with caution. the only thing I could see happening with adding a spacer would be the cam bolt being over stressed for extended periods and eventually breaking, Let me email this thread to a couple friends and see what they think. Quote Link to comment Share on other sites More sharing options...
260DET Posted February 12, 2010 Author Share Posted February 12, 2010 Good idea, I am going to get some advice too. The only motor I will build is a bullet proof one, not interested in anything else. Quote Link to comment Share on other sites More sharing options...
hoov100 Posted February 12, 2010 Share Posted February 12, 2010 Where is Braap on this? I thought he would have shown his face atleast once so far. Quote Link to comment Share on other sites More sharing options...
hoov100 Posted February 12, 2010 Share Posted February 12, 2010 After looking at the z31's cam, it would require a bit more then just adding a 7mm washer, you would need a longer bolt with the big head, you would have to drill it twice for dowel pins and machine the centering ring into it, I don't think you would need a thicker bolt, just a higher grade. Quote Link to comment Share on other sites More sharing options...
260DET Posted February 13, 2010 Author Share Posted February 13, 2010 BRAAP needs an invite? On cam sprocket alignment, see para three of the opening post where I talk about making adjustable cam sprockets. Alternatively the center could be cut out of the stock sprockets and a stepped new center brazed on. I'm sure my machinist friend will sort it. Quote Link to comment Share on other sites More sharing options...
hoov100 Posted February 13, 2010 Share Posted February 13, 2010 BRAAP needs an invite? On cam sprocket alignment, see para three of the opening post where I talk about making adjustable cam sprockets. Alternatively the center could be cut out of the stock sprockets and a stepped new center brazed on. I'm sure my machinist friend will sort it. You could also have the stock center cut out of the sprockets and offset it. That would probably be the safest bet. Quote Link to comment Share on other sites More sharing options...
260DET Posted February 13, 2010 Author Share Posted February 13, 2010 Machinist mate sees no problem converting the stock cam sprockets to adjustable and making the offset 7mm more, the extra load resulting from the additional offset should not be a problem either, the camshaft is very well supported. The tensioner pulley would have to be spaced forward 7mm as well, once again this does not seem to be a problem. Both to do and to bear the load. Note that the pulley stud is M10, the same diameter as the top center cam belt idler pulley on the Z32 motor, which would carry more load I think. An alternative to The Extra Seven Millimeter Solution above is to machine the forged crank to suit a Z31 oil pump. That should be doable but its not a serious option for me at present. Quote Link to comment Share on other sites More sharing options...
hoov100 Posted February 13, 2010 Share Posted February 13, 2010 Well I think its safe to assume that you have created a practical way to use the z32's crank and oil pump on the vg30/33. congrats. Quote Link to comment Share on other sites More sharing options...
260DET Posted February 15, 2010 Author Share Posted February 15, 2010 As a result of fitting a VG30DE/TT crank there will be accessory alignment issues. I have not got there yet but am thinking of using Z32 brackets, pulleys, etc. Not sure about the coolant pump. The other 'issue' is that a DE or TT flywheel will be required, to match the eight bolt crank. There are plenty of light aftermarket ones around at present and suitable clutches, then you can use a Z32 gearbox, which are still available new at a reasonable price. So there are advantages that way as you can end up with a strong transmission able to handle your big power Quote Link to comment Share on other sites More sharing options...
Administrators BRAAP Posted February 16, 2010 Administrators Share Posted February 16, 2010 Well howdy-do boys? Hoov sent me an invite, I finally made it over. Cool stuff going here boys. I too have a fascination with the single cam VG3xE series. Very compact, lightweight, decent power etc. (not as much of a fan of the DE variant). So you are trying get the VG30DE crank in the VG33E block. (Please excuse my newbness, haven't played with these much so I'm not overly familiar with their architecture). So the VG30DE crank is longer by 7mm. Where exactly did this crank gain the extra 7mm in length? Is it a wider front main bearing journal, wider oil pump drive, wider timing belt drive? From the pic below, where was the 7mm added, A, B, C, D, ?... First thing that came to my mind is why not just machine/shave/remove the offending 7mm? Seems like this single operation alone would solve all the alignment/shimming/spacing issues with in one operation. No shimming, no spacers, no sourcing different or alternative accy brackets, etc. If shaving the offending 7mm is possible, would that affect where the woodruff keys land for the timing sprocket and crank dampener vs the VG33E crank? If machining the crank is not an option, going with spacers for the cam gears and shims under the tensioner, as already mentioned, those spacers on the cams should not unduly load the cam bearing journals. Quote Link to comment Share on other sites More sharing options...
hoov100 Posted February 16, 2010 Share Posted February 16, 2010 From what I understand, measurement "a" is where the different comes, because of the larger oil pump. Quote Link to comment Share on other sites More sharing options...
260DET Posted February 16, 2010 Author Share Posted February 16, 2010 Will compare the two cranks side by side tomorrow, from memory its the A to B measurement only which is different when comparing the Z32 crank with the VG33 item. For my application I prefer to use either of the bigger and wider Z32 pumps but yeh, the Z32 crank could be machined to remove that additional 7mm if you didn't want to go that way. The entire snout/nose length of the two cranks is the same. Quote Link to comment Share on other sites More sharing options...
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