| Author | Message | ||
     08herobolt |
Hello Folks, New question from me. I'm looking for the best race cams for my 1996 S1 build. I decided to abort the XB9 piston until next winter so I'm going with the stock bore. I'm also going to machine the case next winter so I'm looking at plug and play. I don't mind buying new springs, lifters, push rods, etc. for this upcoming season. Any suggestions? | ||
| Phelan |
So you're planning on headwork and cams now, bore the cases later? SE .536 cams or similar like NRHS CAT3s are around the biggest you can go without having to replace the pistons, even then you need to check to make sure the valves don't touch them. Those would require a new spring pack at minimum. They aren't the biggest and baddest by any means so you'd likely be looking at replacing them later when you're ready to do more work. The biggest factor is the heads though. Stock '96 S1 heads are lightning heads, which have 1.715" and 1.480" valves, with poor ports. The biggest you can go on these heads without replacing all 4 valve seats (which is expensive) is 1.760" and 1.530" valves. On the contrary, Thunderstorm or XB heads have much larger 1.810" and 1.575" valves from the get go, as well as much better flowing ports. The larger valve seats on these heads can safely fit up to 1.900" and 1.615" valves. So they are a much better fit for your plans IMO. The XB heads (or '04-up XL1200 heads, which are the same) have a combustion chamber that matches the XB9 pistons you wanted, but they will require a new from motor mount, or heavy modifications to your existing mount. The XB heads also have 7mm valve stems and Beehive springs instead of 5/16" stems and double springs, so the XB valvetrain is considerably lighter and can handle higher reving and more lift (up to .560" compared to .500") than the earlier hardware found in all of the Evo XL heads prior. | ||
| 08herobolt |
You're an amazing wealth of knowledge Phelan.  | ||
| Phelan |
Thanks  |
