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Title: Which cam would YOU pick? Post by: modnrod on May 22, 2017, 10:39:17 am I'm building a new engine for when my little Super is on the road. I had a mild-but-sweet 1584 ready but a friend is using it, and that was only going to be an emergency runner anyway. I like small strokers and have decided on a 1745 (76 x 85.5). I was going to use my MV 76mm crank, but after a season of floods and mud it needs a bit of work unfortunately, so likely CB or Empi to the rescue (4140, 4340, a crankshaft anyway).
It has pocket-ported stock 35.5/32 heads, centremount 2BBL, decent exhaust, and initially it will be NA for a while until I get around to building all the stuff I need to then go small low-boost turbo blowthrough. Compression with stock AA 85.5 will end up at about 8.5:1, then with different pistons that have a 9cc dish and different pin height it will end up around 7.6:1, just by taking out barrel spacers and slotting in the pistons (oh, and pushrods too I guess!), no other change at all. Oh, except I might go for bigger valve springs, and maybe perhaps also ratio rockers. The turbo is tiny and I'm only going to run 10lbs max probably less. I expect 5500rpm NA and 6000rpm with pressure. It's ALL about the overlap to be honest.......... (http://i1212.photobucket.com/albums/cc458/MODNROD/VW/Scan_zpssbhblex3.jpg) (http://s1212.photobucket.com/user/MODNROD/media/VW/Scan_zpssbhblex3.jpg.html) I have in the shed....... * 270/234/.330 Int // 266/228/.310 Exh on 111 LSA (beautiful on little 1600s btw, really nice around 3000). * 284/250/.340 Int // 276/242/.315 Exh on 110 LSA (think ratio-rocker version of TCS10, sorta). * Engle FK-41 * Norris 330S .......and I'm thinking when I order the crankshaft I might add a CB #2239, possibly CB #2241, or even pick up an Engle FK-7 or FK-42 locally. Sigh. Decisions, decisions, decisions hey. Which hypothetical cam would YOU pick? (http://i1212.photobucket.com/albums/cc458/MODNROD/VW/Screen%20Shot%202017-05-22%20at%204.54.19%20PM_zps4k0nbuqz.jpg) (http://s1212.photobucket.com/user/MODNROD/media/VW/Screen%20Shot%202017-05-22%20at%204.54.19%20PM_zps4k0nbuqz.jpg.html) PS: credit to Peter Aschwanden for the pics. 8) Title: Re: Which cam would YOU pick? Post by: richie on May 22, 2017, 17:19:13 pm Before I even got to your choices I had decided 41[on 112lobe centers] going on your other parts, make of that what you will ;D
cheers Richie Title: Re: Which cam would YOU pick? Post by: modnrod on May 23, 2017, 00:32:34 am The FK41? Yep, proven in similar packages isn't it?
I wonder how the extra timing duration of the FK7/CB2241 would affect the rev range of operation, both in NA and turbo versions? A V-26, a set of Panchitos and doubling the pressure would be interesting too I rekn! ;D |