(Image/Jeff Smith)

Nostalgia is a big part of the whole muscle car movement. The time-honored approach is to recreate a car or engine that captivated us during our formative years. Perhaps it was the massive torque generated by a big Olds engine or the solid lifter clatter and idle surge of a 271hp 289 small block Ford. Whatever the reason, those long-past days still hold a certain reign over current engine building decisions.

Summit Racing also has muscle car camshafts for small block Chevys, along with muscle car camshafts for big block Chevys too.

To fuel that desire, Summit Racing has made the effort to recreate a series of hydraulic and mechanical flat tappet camshafts from the wild days of the 1960s and ‘70s. Carroll Shelby was making impressions with a hopped-up 289 in his early Shelby GT350 Mustangs, Pontiac’s torque engines were the subject of every Christmas list, the wild Dr. Oldsmobile’s gyrations demanded attention, and of course the Mopar small and big block engines created legends that exist to this day.

Summit Racing Muscle Car Replacement Camshafts pull a few of those more attractive cam designs out of the archives for more gearheads to enjoy.

Summit Racing Muscle Car Cam for Ford 289 Small Block

One of the most popular muscle car replacement cams for the 289ci small block Mustang is the 271 hp four barrel camshaft that Summit Racing has faithfully reproduced. (Image/Jeff Smith)

We’ll start with the small block Ford cam and work our way through the entire collection, and supply a detailed list of the specs for each cam at the end of this story.

A couple of years after the Mustang was introduced, Shelby stuffed a hi-po cam in a 289 that produced a factory rating of 271 hp and that engine quickly became a popular choice that remains true today. This is the only mechanical cam in this mix of performers with decent specs of 228 degrees at 0.050 inch duration with nearly 0.500 inch valve lift using the stock Ford rocker ratio.

When tied into a small block with 9.5 or 10:1 compression, this makes for great performance as well creating as that classic small block solid lifter sound. This is a great Ford cam choice for anyone wanting to emulate that early Shelby power program (especially when backed with a manual transmission).

Summit Racing Muscle Car Cams for Pontiac V8

Moving up in the displacement ladder, Pontiacs were early standard bearers in the muscle car movement. The milder of the two Summit Racing Muscle Car hydraulic lifter cams originated with many of Pontiacs stalwart engines including the 389, 400, and 455. This is a relatively mild cam with specs at 0.050 inch tappet lift of 212/215 degrees and a valve lift of 0.408 inch for both intake and exhaust. This would be a great choice for a daily driven muscle car and while it does give up peak horsepower because of its short duration, it also offers outstanding low and mid-range torque potential—which is what Pontiacs have long been known for delivering.

The milder of the two Pontiac cams would be a great addition to a larger Pontiac road car like this 2+2. (Image/Jeff Smith)

The next step up for the Pontiacs is the Summit Racing Muscle equivalent of the Ram Air IV cam with a stated rpm power range between 2,200 and 5,400 rpm. With 231/240 degrees of duration at 0.050 inch tappet lift, this cam was aimed by factory engineers to pump up the power on its initial application for the early Ram Air II and IV GTO and Firebird.

This cam’s long duration requires a minimum of 10:1 compression and a high stall converter when used with automatics in order to obtain good results. This cam can also be used in larger 455ci engines with great results. Conversely, it’s not recommended for smaller displacement 350ci engines and those with lower compression. A better choice would be the previous 068 “S” Muscle cam.

The Muscle Car replacement cam list extends even to Pontiac engines with two different flat tappet hydraulic versions available.. (Image/Summit Racing)

The point about compression ratio is important as a reference for all engines because as duration increases, the intake closing point is delayed. With a lower compression engine, this later closing point tends to reduce the cylinder pressure at low engine speeds, which reduces power and can contribute to an engine that feels sluggish and unresponsive.

Larger displacement engines can accommodate this situation slightly better but still need a higher than stock compression ratio—around 10:1 to return the engine’s responsiveness when selecting a cam like this RA IV version.

Summit Racing Muscle Car Cams for Oldsmobile V8

Moving on to the Oldsmobile camshafts, it’s important to mention that Oldsmobile used two different lifter bank angles with its engines. It’s too complex to go into detail here, but the angle is formed by the intersection of a vertical line through the camshaft centerline intersecting with the angle of the lifter bores in the block. Some engines used the traditional 45 degree angle used on most other GM engines, while some used a slightly different 39 degree angle.

This angle is critical because different bank angle Oldsmobile camshafts can be interchanged but the engine will not run correctly since the cam timing will be affected if incorrectly applied.

Summit Racing also covers the Olds folks with a couple of camshafts for the big-inch Rocket brand engines. The more aggressive of the two cams is aimed at the larger displacement 455 engines but is easily very streetable. (Image/Jeff Smith)

The first Olds Muscle Car replacement cam is the recreation of the 1970 310hp 350ci Olds hydraulic cam (original GM part number 4000084, Summit Racing PN SUM-4220). This engine used the 39 degree lifter bore angle, so this cam should only be used on engines with this same lifter bore angle. This cam is relatively mild at 187/200 degrees of duration at 0.050 inch tappet lift and 0.399/0.401 inch valve lift. The second Olds camshaft faithfully recreates the W-31 mild race cam, GM part number 402194, right down to its rowdier idle. As a bonus, by advancing it five degrees, you’re essentially mimicking the W-30 cam too.

Summit Racing Muscle Car Cams for Small/Big Block Mopar

While most Mopar attention seems to concentrate mainly on big block engines, Chrysler did some wonderful things with its LA small block engines. Summit Racing offers a version of the strong 1968 340ci small block camshaft that would make a great choice for a Dart Swinger or other A-body car. Summit Racing’s Muscle Car cams offer very similar performance characteristics but show up with slightly different specs using more modern lobe profiles to add a little spice to these camshafts. The SUM-6920 camshaft offers 209/220 degrees of duration at 0.050 with 0.429/0.440 inch lift for this hydraulic flat tappet cam. Don’t let the mild specs fool you, this is a great cam that will wake up that small-block, even if it’s only a 318.

The Summit Racing Muscle Car series didn’t forget the big block B and RB (raised block) wedge engines with a pair of cams to choose from. The first, SUM-6420 pulls its influence from the 335hp 383 cam (equivalent to the Mopar PN 3512907) with 213/225 degrees of duration at 0.050 inch tappet lift and 0.447/0.459-inch valve lift for the intake and exhaust respectively. With a relatively wide 115 degree lobe separation angle, this cam will make great torque in a 383 or larger big block.  

You may have noticed on some cam cards (like this small block Mopar cam), that the intake opening and exhaust closing specs at 0.050 inch tappet lift are in parenthesis. This indicates, on the intake opening side for example, that the intake opens 8 degrees after top dead center (ATDC) rather than Before Top Dead Center. This is because the duration is very short. To reveal how this works, merely add 37 degrees (Intake Closing) to 180 degrees and then subtract the 8 degrees since it indicates ATDC. So 37 + 180 – 8 = 209 degrees which is the duration at 0.050 inch as indicated on the timing card. The same math applies to the exhaust side. (Image/Summit Racing)

The second hydraulic flat tappet Mopar cam is very similar but based off the 365hp 440 wedge RB cam with 208/210 degrees of duration and 0.431/0.429 inch valve lift. This cam employs a slightly tighter lobe separation angle of 113 degrees and also promises strong torque for either 383 or 440 engines.

With this selection of eight different cams for four different automakers, there’s something here for just about any discerning muscle car fanatic who doesn’t feel like following the Chevrolet herd.


Summit Racing Ford, Mopar, Olds & Pontiac Muscle Car Camshaft Part Numbers, Specs & Comparison Chart

We’ve included a chart below, but CLICK HERE if you want a downloadable/printable PDF comparison spec chart of all the Summit Racing Muscle Car Camshafts for Ford, Mopar, Olds & Pontiac.

Click on the image to enlarge, or click here for a downloadable, printable PDF. (Image/OnAllCylinders)

Summit Racing Muscle Car Replacement Cams Parts List

  • SUM-3610, 271 HP 289 Small Block Ford, C30Z-6250-C
  • SUM-6920, Mopar 340 Small Block
  • SUM-6420, Mopar Big Block      
  • SUM-6421, Mopar 365 HP 440 Big Block, PN 2532190
  • SUM-2820, Pontiac 068 HO / Ram Air “S”, PN 9779068
  • SUM-2821, Pontiac Ram Air IV, PN 9794041
  • SUM-4220, Olds 1970 310 HP 350, PN400084
  • SUM-4221, Olds W-31 455ci 390 HP, PN 402194

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Author: Jeff Smith

Jeff Smith has had a passion for cars since he began working at his grandfather's gas station at the age 10. After graduating from Iowa State University with a journalism degree in 1978, he combined his two passions: cars and writing. Smith began writing for Car Craft magazine in 1979 and became editor in 1984. In 1987, he assumed the role of editor for Hot Rod magazine before returning to his first love of writing technical stories. Since 2003, Jeff has held various positions at Car Craft (including editor), has written books on small block Chevy performance, and even cultivated an impressive collection of 1965 and 1966 Chevelles. Now he serves as a regular contributor to OnAllCylinders.