We have, and focus on, re-ground flat-tappet camshafts. We try to keep a supply of cores available for faster turn time and when we have a large supply of any one part we will sell them outright.
Both new and re-ground camshafts are available for the Mopar V-8. The 51-55 Chrysler, all Desoto, and all Dodge only have flat-tappet regrinds available at this time; All engines can be fitted with custom billet cams, generally a roller type, but we do not supply them.
New Camshafts for the 354 and 392 engines are available, sporadically, from various manufactures.. The 354 camshaft can be used in the Chrysler 301 and 331 as long as the associated 354 parts are also used as a package.
We would be happy to help you select a profile that would be appropriate for your needs. Use the ‘Contact’ page.
CAMSHAFTS
Part # . . . . Description . . . . . . . . . . . Price
9-100 New cam, 301-331-354, various grinds, Flat tappet and rollers
9-105 New cam, 392, various profiles, Flat tappet and rollers
**New cam availability is dependent on core supply. Call to verify**
9-110 Regrind, all V-8 engines, labour only . . . . . . . $175
9-115 core charge, varies with application, call for specific details
LIFTERS
9-120 Hydraulic Valve Lifter, set, for pushrod with 0.250" tip 175
9-121
9-122 Mechanical lifter, set, for pushrod with 0.3125" tip 130
PUSHRODS
9-125 Adjustable, high-strength tube, various tip sizes . . . 185
9-126 Fixed length, various tips, 0.3125" or 0.375" dia tube . 170
Camshafts currently in stock are listed on the inventory clearance page
General Camshaft Info…
As with most aspects of any engine, the selection of a camshaft profile is as personal as the color of your shirt. The reality, however, is that not everyone looks good in a pink shirt just as not everyone needs, or can use, a specific cam profile.
The cam profile must be selected based on consideration of the rest of the vehicle and engine components:
• How much compression?
• How much carburetor? or EFI?
• Exhaust manifolds or headers?
• Vehicle curb weight?
• Automatic or manual trans? Converter stall speed?
• Final gear ratio?
• Desired cruise speed/rpm?
Additionally, the fine details of the engine overhaul such as valve size, valve spring rates, stock or modified ports and other information should also be part of the selection process. The following observations are in regards to the EarlyHemi engines although it generally applies to many engine designs.
LIFT:
Most of the ‘older’ Mopar engines, including the EarlyHemi engines, have installed valve spring dimensions of 1.2″ open and 1.7″ closed. Simple math tells us that you are left with 0.5″, this means that the max valve opening should be less than ½” because we need to factor in things like coil bind. There are a number of ways to get around this limitation but only by small increments. The spring can be made with smaller diameter, stiffer wire, to avoid coil bind, but stiff springs (high spring ‘rate’) can create other problems; worn cam lobes, bent pushrods, broken exhaust rocker arms, rocker shaft galling, etc.
High lift cam profiles also create more scuffing/sliding of the rocker arm tip across the valve tip. For many engines, this problem is solved by using roller tipped rockers and/or lash caps (to increase the surface area), however, with the design of the EarlyHemi rocker assemblies, these will either be very expensive or not very practical.
Again, because of the rocker arm design, high lift profiles can also create interference between the spring retainer and the rocker arm. A beehive style spring, with the smaller diameter retainer, is useful in this regard.
A very common mis-conception is that the easy fix is to either cut into the spring seat (to increase operating range) or to sink the valve in the seat (to raise the top of the spring and increase the operating range); cutting into the seat is dangerous due to the fairly thin cross section of the casting in that area (potential water jacket leaking), and raising the valve tip goes back to the rocker arm issues previously mentioned. Additionally, sinking the valve into the seat disrupts the air flow and generally hurts performance.
If valve lifts over ½” are absolutely necessary then the rocker stands must be modified to allow the shafts to be repositioned to allow for longer-than-stock valves and the then needed longer springs. This modification is difficult to accomplish correctly and should be left to an experienced machinist. Shifting the position of the shafts also raises the potential for pushrod interference through the cylinder head and enlarging the pushrod hole creates the possibility of damaging the casting.
DURATION:
Cam profiles in years past (1950-1960’s) focused on large duration numbers to increase performance in part due to the limitations of lift noted above.
Until recently, the cam manufacturers had stopped casting new cam blanks for the EarlyHemi engines so we were left with regrinding stock shafts in order to create new profiles (the only ‘new’ cores are for the 354 and 392, however, the supply of cores is sporadic). Large duration numbers, either ‘advertised’ or ‘@ 050’, were then a function of reshaping the cam lobe to make it appear ‘fatter’ to the lifter thus increasing the duration. In order to make an existing lobe fatter then it must, at the same time, be made shorter which limits total lift. This operation affects the base circle as much as the lobe itself and requires either adjustable pushrods or adjustable rocker arms to maintain proper preload on the hydraulic lifters, when used.
Additionally, extreme caution must be exercised if large duration profiles are used to insure that the valves have adequate clearance to each other at the ‘overlap’ position.
LOBE SEPARATION ANGLE (LSA)
Lobe separation angles (the included angle between intake and exhaust lobes) are fixed at the time that the cam core is cast and initially machined. Minor changes in the lsa can be made but at the expense of major cutting on the lobes thus making them smaller. It is not recommended.
Most EarlyHemi engines have an lsa in the 109° to 112° range; the exception is the DeSoto 276-291 and 2-bbl versions of the 330 which have an lsa as great as 122°. Large lsa create a very smooth idle which was a trade mark for the DeSoto brand of the early 50’s.
Conversely, the currently available ‘Thumper’ cam series from Comp Cams has an lsa in the 106° area. This is the driving force in the ‘Thumper’ line; a very rough idle.
EFFECT OF THE LOBE SEPARATION ANGLE
LSA……………………………………Narrow………….Wide
Intake valve opens………………Earlier…………..Later
Intake valve closes………………Earlier…………..Later
Exhaust valve opens……………Later…………….Earlier
Exhaust valve closes……………Later…………….Earlier
Valve Overlap……………………..More…………….Less
Cylinder Pressure………………..Gain……………..Lose
Idle Quality………………………..Worse……………Better
Idle Vacuum………………………..Less……………..More
Torque Curve……………………..Peakier………….Flatter
Peak Torque……………………….More……………..Less
High RPM…………………………..Drops Off……….Hangs On