- This topic has 5 replies, 3 voices, and was last updated 20 years, 2 months ago by
.
- Posts
I just read through the STARS rules for the ‘spec racer’ class. It states that the flex pipe length is ‘open’ (no restrictions on max/minimum). Hmmm, I’m sure there are points of diminishing returns but can anyone provide a baseline number?
We used to have to measure it from the beginning of where the header meets the cylinder head, to the first crease in the exhaust pipe.
Start at 405mm…….shorter i believe will make it have more Top end…..longer more torque and bite off the low end.
I had a Sonik a couple years ago that I had some machined flex pieces for of different lengths. I had one at the maximum allowed and one at the minimum allowed for different tracks. I used the short one at IMI where the motor is in high revs alot, gave it noticably more top end. Used the long one at Bandi to power outta the corners. They were machined out of regular ol’ steel tube and worked well to not have to mess with that goofy flex pipe stuff, sealed alot better too. Dunno if the rules are the same this year that would permit using a solid piece but they didn’t say anything that disallowed it in 2004.
I’d agree with the solid flex…..but it could possibly put more strain on the header pipe against the head. The only issue we had with the flex was it crushing and making the pipe too small……happened to me at Reno when it went to 403mm….got DQ’d out of a 3rd place.
Did you see any other issues with the solid Taylor? Good advice though for sure, i always hated the crushing of the flex pipe.
Never had a problem with it at all. The only good thing that comes from the flex pipe is that it’s a crush point like you said for an accident. If you get in a knarly wreck and your pipe gets bent, the flex pipe will deform and save your header. It’s gotta be a pretty bad wreck tho because I had someone drive over the back of me and hit me in the back, tire marks all over the pipe and my seat. It bent the pipe bracket to the chassis down but I had enough play in the solid flex piece to save the header, no damage to think of.
- You must be logged in to reply to this topic.