timzcarman Posted November 10, 2012 Share Posted November 10, 2012 Not an S30 but still datsun! http://www.bmsc.com.au/forums/rallying-technical/29129-datsun-l-series-build.html Really like the look of the rocker arms! Quote Link to comment Share on other sites More sharing options...
Agno Posted November 10, 2012 Share Posted November 10, 2012 Those roller rockers look interesting. I wonder if anyone has used them on a 6 cylinder engine before Quote Link to comment Share on other sites More sharing options...
peter mc Posted November 10, 2012 Share Posted November 10, 2012 there on a race car up north , wes engines made them , Quote Link to comment Share on other sites More sharing options...
dat2kman Posted November 10, 2012 Share Posted November 10, 2012 Lee falkner had his Z at PI for the six hour. Fair bit of development cost, which of course many baulk at doing. A shame. Whatever happened to running a well built prod stock based ralky car? Apparently nowadays, Escorts are all Group 4 spec, bdg, fuel injected sequential 6 speeds, Batesey has built a RA40 Celica with a BEAMS 3SGTE running injection, but at least he has a H pattern Holinger. Classic rallying my sweet arse! Quote Link to comment Share on other sites More sharing options...
chris240 Posted November 10, 2012 Share Posted November 10, 2012 Im in love with that manifold Quote Link to comment Share on other sites More sharing options...
luvemfast Posted November 11, 2012 Share Posted November 11, 2012 Those rockers ARE interesting. Have you looked into anything like that with Les Peter? Quote Link to comment Share on other sites More sharing options...
peter mc Posted November 11, 2012 Share Posted November 11, 2012 we have but you need a spring that will take the roller cam , and there is so much flex on the cam you don't have any support on the cam from the 8mm bolts, and we can get the same lift from a standard cam with less spring make the same power , better to spend the cash on the port to make air flow , we move the guide and seat and make new long rockers now and have found 30 more hp with the same cam , the cam and roller rockers are not the the part that stops power intake flow does Quote Link to comment Share on other sites More sharing options...
KatoKid Posted November 11, 2012 Share Posted November 11, 2012 we move the guide and seat and make new long rockers now and have found 30 more hp with the same cam Pete, assume that when you make the longer rocker you are lengthening just the part between the cam contact point and the valve stem (the distance from the pivot to cam contact point stays the same), there by effectively increasing the ratio of the rocker and giving more valve lift for the same cam? Quote Link to comment Share on other sites More sharing options...
peter mc Posted November 11, 2012 Share Posted November 11, 2012 yes mate there longer on the tip giving a better rocker ratio , every bit helps . We can make the same hp as the intake port says on the flow bench, every time we build a better we make more hp Quote Link to comment Share on other sites More sharing options...
KatoKid Posted November 11, 2012 Share Posted November 11, 2012 Bonus! Not often you get a win - win situation like that.......most of the time there's a compromise trade off. Do you move the valve location to get a bigger valve or is it just to optimise port configuration or unshroud the valve? Quote Link to comment Share on other sites More sharing options...
peter mc Posted November 11, 2012 Share Posted November 11, 2012 We do it to optimise the position and move it away from the bore and 2mm away and 2mm back , we weld the chamber, and port it so the air stays in contact with the port floor Les has made some big gains of late , the hard part is making the port work all over not just in the hi lift , , also the cams we are using have more lift at bdc than ever before on the exhaust side , we have been working hard to get every bit from them Quote Link to comment Share on other sites More sharing options...
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