Updates & changes: I can't tell a "short" story! LOL! |
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Updates & changes: I can't tell a "short" story! LOL! |
Cracker |
Oct 13 2016, 08:04 PM
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#1
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Advanced Member Group: Members Posts: 2,148 Joined: 2-February 10 From: Atlanta (area) Member No.: 11,316 Region Association: South East States |
Silver lining - starting from scratch is ALWAYS better!
A month ago, I ran into my first real problem, at Barber - I blew an outer CV less than 2 laps into the weekend. The root cause was I had a lowered the drivetrain to avoid a section of existing rear structure (lazy is never a good excuse!) - this caused tthe angles of the CV to be too extreme. In addition, I had also lowered the chassis beyond what was practical with my stock suspension set up. One caveat: The car liked it and felt great on the track but the angles were not sustainable! In speaking with Chris Foley (thanks a million for answering my calls!!!) - he likes the hub center to pivot shaft centerlines to be within .250" of an inch to each other. My pivot shaft was 1.5" lower and coupled with the lowered drivetrain (which lowers the drive flange on the transaxle) - my CV went kaBOOM. My pivot shaft to hub delta is now only .5" - more inline with what Chris would like to see. I share all of this (my stupidity) to hopefully help someone else avoid the same pitfalls. I weighed the options and there really wasn't any choice - to make the car safe at high speeds and to KNOW the changes would allow the CV's to last, I had to cut out the rear structure out, raise the trans to the proper level, fabricate the new exhaust, and rebuild everything around what was left. I also had an issue with my wing strut at high speed, staying stable - deflecting rearward. The wing was a variable pitch...but it wasn't supposed to be! All of this re-work provided a great opportunity to fix this along with everything else. Another bonus, in picking Mr. Foley's brain was integrating his suggestion to implement structure that helps keep the longs from twisting - in relation to each other. It is still not exactly complete nor what I'd like in total structure but if I add too much more - people might call it a race car - not a hot-rod! (IMG:style_emoticons/default/poke.gif) My exhaust was a little loud - not too bothersome to me but it didn't meet the 103 dB requirement at many tracks - even ours out East. I "invested" in the Burns Stainless 2-stage system for LS engines. They have a removable baffle which creates an more open system. It is supposed to knock the sound down to about 97/98 (I was at 106!). The cans were too big locate below the floor - so topside they are! I like it anyway (even if it raises my CG)! Here are a few pictures of the completed project - just in time for tomorrow's departure for Road Atlanta. If any of you local/regional folks want to come on out - I'd enjoy meeting you - come on by. No cost to get in - you'd be my guest. Now if more than 3 people looked at the "paddock" - someone might actually show up. (IMG:style_emoticons/default/blink.gif) If you have suggestions and ideas - please share them. Tony |
stownsen914 |
Oct 16 2016, 04:41 AM
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#2
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Senior Member Group: Members Posts: 913 Joined: 3-October 06 From: Ossining, NY Member No.: 6,985 Region Association: None |
Nice work on the car!
What kind of power are you putting down, and which CVs are you using? Scott |
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