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1958 KR Cams

PostPosted: Sat Aug 24, 2019 9:05 pm
by hugoct
The 1958 KR cams (25499-58R) are listed as having the intake lobes stamped "A" and the exhaust lobe is stamped "L".
The "A" Intake timing is listed as open 76/72 close with .420" lift and the "L" Exhaust timing is open 68/38 close with .375" lift.
The "L" exhaust from 1969 has timing of open 65/40 close with a .395" lift.
Anyone have any experience with the 58R "L" exhaust compared to the 69R "L" exhaust?

Re: 1958 KR Cams

PostPosted: Sat Aug 24, 2019 11:16 pm
by panic
No, but the engines are pretty different.
1958 is a conventional KR, 1969 may be a "low boy" with shortened cylinders, 1" shorter rods, and dual carburetors. This generally means analyzing cam events as regular business.

Re: 1958 KR Cams

PostPosted: Sun Aug 25, 2019 11:40 am
by hugoct
The 1968 and 1969 Team engines whether for "lowboy" road race or "highboy" dirt track ran standard length rods and cylinders.
The 1968 and 1969 Team engines were distinguished by steel or aluminum dual carb manifolds with Tillotson carbs, 200, 400 or 600 thous dome pistons and in some cases small port cylinders.
The ultimate cams they arrived at were the J intake M exhaust combination which was a lobe center compromise on the exhaust side between the "L" and "K" exhaust.

Re: 1958 KR Cams

PostPosted: Sun Aug 25, 2019 5:32 pm
by panic
What was Branch talking about?

Re: 1958 KR Cams

PostPosted: Sun Aug 25, 2019 8:18 pm
by hugoct
The Factory Team 1968 and 1969 Lowboys and their engines were built in Milwaukee by the Racing Department. Jerry Branch built a KR project with Gorden Jennings of Cycle World that had a short rod engine. Short rod experiments were also conducted by Tom Sifton and Leonard Andres.