Classic Inlines Camshafts are currently stocked in fourteen different profiles (the most in the industry) and are made from the highest quality cores available. All camshafts are ground from new cores and are not regrind's as offered by some manufacturers. All of our camshafts are ground by Clay Smith Cams. Unlike some manufacturers all Clay Smith Cams are ground striaght up, however for most street applications we recommend installing the cam with 4 degrees of advance for optimum performance.

Listed below is a general group classification for aftermarket cam profiles. The durations shown are based on .050 cam lift with a 112° lobe center. The descriptions within each group show the characteristics of the cams in that group, as well as any recommended modifications to the car or engine which may help you reach the desired performance level.

• Class I (200° - 215°)
  Good idle quality. Low rpm torque and mid range performance.Will work with
  stock or slightly modified engine. Manual or auto transmission.
• Class II (215° - 230°)
  Fair idle quality. Good low to mid range torque and horsepower. Will work with
  stock or modified engine. For use with manual or automatic transmission with
  mild stall converter. Lower vacuum than stock.
• Class III (230° - 245°)
  Rough idle quality. Good mid to high rpm torque and horsepower. For use with manual transmission or high stall automatic. Requires improved induction, exhaust system, and ignition system. Combination street and drag. Will have low vacuum.
• Class IV (245° - UP)
  Rough idle quality. Mid to high rpm torque and horsepower. For serious racing.
  Need proper selection of rear axle ratio and improvements in carburetion and exhaust systems. For use with manual transmission or automatic with very high
  stall converter. Will not have enough vacuum for power accessories.

Are you wondering which camshaft to choose for your application? We would be happy to assist you with your selection, but it helps if you have a basic idea of the terminology and what the numbers mean. Start by reading the articles in our tech section, "Selecting the Right Camshaft", Understanding Lobe Centers", and "Static vrs Dynamic C/R". You can also use the Dynamic Compression Ratio Charts to assist in selecting the proper cam profile. If your still not sure, send us an e-mail and we'll help you out. Include as much information as possible in your e-mail, including: engine size, compression ratio, head work & valve size, induction type & CFM, type of exhaust system & size, type of transmission, rear gear ratio, tire size, primary driving habits (street, strip, highway), vacuum accessories (if any), and your desired goal (mpg/economy, power, idle quality, etc).

A lifters primary function is to maintain precise valve timing under all engine operating conditions. In our opinion, Clay Smith lifters do this better than any other lifter on the market. Clay Smith Lifters are sophisticated, highly engineered, precision components manufactured to demanding specifications. If you were to examine the inside of a Clay Smith Lifter you would see why they are the choice of mechanics and race teams around the world. No other lifter is designed, engineered, and manufactured to such exacting tolerances. Get the Best, get Clay Smith Cams and Lifters.

Classic Inlines Cam Profiles (170/200/250ci engines) Part # Adv. Dur. .050 Dur. Lift @ 1.5 Lift @ 1.6 Lift @ 1.65 Int Closes Lobe Center RPM Range Comments Code CSC 264-08 SHS 264/264 214/214 450/450 480/480 495/495 60 108 1250-5000 A-D-G-J-M CSC 264-10 SHS 264/264 214/214 450/450 480/480 495/495 62 110 1400-5200 B-D-G-J-M CSC 264-12 SHS 264/264 214/214 450/450 480/480 495/495 64 112 1600-5400 A-D-G-J-M CSC 264-08 DHS 264/274 214/224 450/450 480/480 495/495 60 108 1250-5000 A-D-G-J-M CSC 264-10 DHS 264/274 214/224 450/450 480/480 495/495 62 110 1400-5200 B-D-G-J-M CSC 264-12 DHS 264/274 214/224 450/450 480/480 495/495 64 112 1600-5400 A-D-G-J-M CSC 274-08 SHS 274/274 224/224 450/450 480/480 495/495 65 108 1300-5200 B-D-G-J-M CSC 274-10 SHS 274/274 224/224 450/450 480/480 495/495 67 110 1500-5400 B-E-H-K-N CSC 274-12 SHS 274/274 224/224 450/450 480/480 495/495 69 112 1700-5600 A-E-H-K-N CSC 278-08 SST 278/278 228/228 460/460 490/490 505/505 71 108 1400-5600 B-F-H-K-T solid lifter CSC 278-10 SST 278/278 228/228 460/460 490/490 505/505 69 110 1600-5800 B-F-H-K-N solid lifter CSC 278-12 SST 278/278 228/228 460/460 490/490 505/505 71 112 1800-6000 B-F-H-K-T solid lifter CSC 278-14 DST 278/272 228/224 460/448 490/478 505/492 78 114 2000-6200 B-F-H-K-T solid lifter CSC 280-08 SHS 280/280 238/238 425/425 455/455 469/469 72 108 2200-6300 C-F-H-L-O CSC 280-09 HHS 280/280 231/231 480/480 510/510 528/528 74 109 2000-6200 C-F-I-L-O CSC 292-10 SST 292/292 240/240 495/495 528/528 563/563 76 110 2600-6800 B-F-H-L-T solid lifter CSC 292-12 SST 292/292 240/240 495/495 528/528 563/563 78 112 2800-7000 B-F-H-L-T solid lifter

Comments

A) smooth idle    B) lopey idle    C) rough idle
D) good vacuum   E) adequate vacuum    F) marginal vacuum
G) manual or stock converter    H) manual or high stall converter    I) manual only
J) stock gear ratio OK   K) min. 3:00 gear ratio    L) min. 3:20 gear ratio / 3:50 recommended
M) stock compression ratio OK    N) min 9.0 CR recommended    O) min 9.5 CR recommended
T) solid lifter - recommended for turbo charged applications, as well as naturally aspirated

• Always install new lifters with a new camshaft. Installing used lifters with a new camshaft can cause premature failure of both the cam and the lifters.
• Do not allow the engine to run under 1500 rpm for the first 20 minutes. The first
  few minutes of the engine operation are the most critical and tests have shown
  that if there is no metal pickup or spalling during this period, the camshaft will
  wear as long as other engine components.
• With performance cams - usually you will have to advance the distributor timing
  (on the vibration damper) more than stock specifications.
• When installing any high performance or racing camshafts into a engine, check
  to make sure there is adequate clearance between the valves and pistons and
  make sure the valve springs do not compress solid (coil bind). You might have
  to change the valve spring and retainer, or use an aftermarket performance
  valve spring

Other related articles:
Understanding Lobe Centers - Static vrs Dynamic Compression
Cam Installation Tips - Adjusting Your Valves
How to Degree Your Cam - Clay Smith Cam Cards