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Car in the shop for motor issues- cams and lifters
Well, the shop finally called me and told me several lifters are bad and they suspect the cam is either a bad match to my components or something is wrong with it. He says that the cam is acting like it is too big for normal street use or off a tooth. Vacuum reading were really low. Since I want a daily driver I told him to go ahead and change the cam out. He is neighbors with the Competition Cam guy here in Memphis so he will pick me out a good street cam to go with my 4 barrel and high rise manifold. I read that some of these cars have retarded timing chains to improve emissions(don't want that either). Would love to know how I would know that when the cam comes out. They will pull the manifold and cams out Thursday and let me know what they see. Compression check was o'k which means I get to save some money.

Any thoughts on the right competition cam I should get? I am not sure about compression setup of the engine.

Bright lime 72 Mach 1 with 351C 4V, with summit 600 carb(have a Holley too), Edelbrock dual-plane manifold, Hooker headers, 3 inch exhaust with flowmasters, 17 inch Eleanor wheels, FMX tranny, A/C, P/S, front disks and 350 rear gear. Drive it to work every day.
For a daily driver a bigger cam is not better. I ran their 268 grind and it worked nicely in a 351W I built for street duty.

[Image: 386_07_10_13_5_58_42.jpeg]
My Mustangs:
71 M-code Mach 1, Medium Blue/White Sport, 4R70W, 3L50, Factory Ram Air.
72 Q-code Mach 1, Pewter/Black Sport, 4-spd, 3L25.
65 Convertible, Britney Blue/White/White, more modified than original.
05 Convertible, Legend Lime/Tan/Tan, future classic??
I know from my Harley about cam choice. I have what was in it and it has never run right so I am going to go to street cam. I have full length headers, 3 inch exhaust with flowmasters, MSD ignition and many other go fast goodies. This is what it came with and my car runs kind of crappy. Idle is a bit hard to get right as well and the vacuum operated accessories are not getting enough vacuum to work effectively. I want it to run properly. Any thoughts on a gearing change at this time? Says it has 2.75 from the factory. They will be changing seals on rear-end and ring and pinion might be good to change at this time.
Don, is the car in your signature the factory Pewter color?

Bright lime 72 Mach 1 with 351C 4V, with summit 600 carb(have a Holley too), Edelbrock dual-plane manifold, Hooker headers, 3 inch exhaust with flowmasters, 17 inch Eleanor wheels, FMX tranny, A/C, P/S, front disks and 350 rear gear. Drive it to work every day.
Where did you take it, Ralph? Have you considered switching over to a retrofit roller cam? That would eliminate a lot of issues with wiping the cam during break in, or at some point down the road. I've gotten a tour of their manufacturing plant, and it really is very cool. They have CNC machines, but they also have guys on lathes grinding them manually, too. The techs at Comp Cams are really car guys, although a lot of them are into chebys. But still they can provide a lot of good advice on cam selection for your application.

As far as the rear end, with that FMX tranny, the 2.75 will keep the revs down while cruising at highway speeds. If you plan to do an AOD swap, then 3.25 or 3.50 might give you more acceleration from a standing start. PM me. Maybe we can meet up at the cruise up there on Germantown Parkway on Tuesday evenings.

Good luck,

Rusty, a 1973 Mach 1, needs a lot of work.
Billy, a 1976 Ford Bronco, also needs a lot of work.
El Guapo, a 1986 F150, frame-off Resto-Mod.
Bubba, my 1994 F150, daily driver
Formerly, a 1973 Ford Mustang Coupe - a work in progress, then a car-b-qued banana.
It depends on what the future holds for your car. The current transmission and rear end ratios are likely the biggest factors to consider. I don't believe Ford intended for the 4V 351C engines to be low end torque monsters and the huge intake port tracts seem to be a factor that is at least partially responsible. Also, the valvetrain is something that must be addressed at the same time. If you stick with stock sled type rockers and stock heads, only so much lift can be used. If the stock valves are still in place (4grooves at the keepers as opposed to one) then the valves are two piece. They can fail with disastrous results.


I'd look for something of this nature, but go ahead and pull the heads and replace the valves if necessary and freshen them up plus any necessary machining. Do it right now or risk more damage and costs down the road.

Just buy a fresh timing chain set-they shouldn't be reused for the most part.

[Image: 1_01_07_15_8_53_18.png]

"I love my Hookers!" and "Get some Strange" probably have a different connotation to non automotive enthusiasts!
This may possibly be a forum to post your questions and get some feedback on cam profiles and performance.


I went bone stock so I cannot comment on upgrades. I will be installing the FE 268H profile in my 390 this weekend. Ordered the Cam Kit through Summit. Much better price than Will Call and Comp. This gets you a matched setup so you know the cam will work with your valve train.

Who do you have doing the work locally?

Maybe we could all meet at the Tom's Cruise on Tuesday night in Cordova. Next week I may bring the 72 if the weather cooperates.

72 Mach 1 H-Code (Concourse driven restoration)
67 S-Code Factory GT with 4-Spd

68 Mercury Cyclone (Pro-Street project)
If you want a great streetable all around cam a bit more lift than stock you can't go wrong with one of these..
No need for a roller cam buy the package lifters & cam..
I very pleased with the install in my build..

+1 on Jeff73 Mach 1's post. It sounds like the car was originally a 2V car with the 2.75 gears. In my opinion there is no high performance cam that will work well with 4V heads and a 2.75:1 gear for street use. Jeff's comments on the valve train are all valid. Dropping a valve usually results in starting over. The compression ratio is about 8.6:1 with open chamber 4V heads and about 9.5:1 with Closed chamber heads. Who ever chooses the cam should ask for this as well as several other things. If they don't, it is not the right person to be choosing the cam. At stock displacement the heads want a lot of lift .550 or more at the valve and relatively short duration numbers, less than 220 with about 4 to 6 degrees more on the exhaust side if headers are used, 10-12 if manifolds are used. The canted valve heads, Ford or Chevy, want a bit wider lobe separation angle (LSA), about 2 degrees, than an in line valve head. For this kind of build I'd suggest a 112 or 114 LSA to give it good street manners. You must match the valve springs and installed height to the cam, retainers, and keepers used and no, they are not all the same. The same is true of pushrod lengths. The lengths need to optimal for optimal performance. Not matter what cam and timing set is selected, the cam should be degreed by a competent engine builder. It can make the difference between having your expectations met or being disappointed. If you can plan on changing the gear and upgrading the valve train even if it means waiting until it can be afforded. I'd also suggest you contact several cam companies and get several recommendations. There are "Ford guys" at Lunati and Schneider, just to name a couple. None of this is as simple as some would like us to believe. Good luck on the effort. Chuck
My 72 was originally a FMX with 2.75 rear, was a 2v w/open heads and pinged with 93 octane and not much advance. Went with alum heads and a crower hyd roller and crane roller lifters. Engine is great. Dyno shows 375hp with factory exhaust manifolds. I swapped in 3.25 gears and a higher stall TC.
I brought it to the shop because I don't have the time to do this or the desire. I took it to a reputable place and I am fairly confident that it will be done right. I will go mild and make sure it is for a low compression setup. I know I have 4v heads but don't know if they are closed chamber(believe those have a different letter on them-M). I want a daily driver so a very mild cam is all I am interested in. Plan to add a new timing chain as well. I need the car to start every day and get me too work. If it does not do that I see a Pontiac G8 GT(SLP if the price is right) in my near future. That car will get me there fast.

Time to go out and work on my drivers seat.

Bright lime 72 Mach 1 with 351C 4V, with summit 600 carb(have a Holley too), Edelbrock dual-plane manifold, Hooker headers, 3 inch exhaust with flowmasters, 17 inch Eleanor wheels, FMX tranny, A/C, P/S, front disks and 350 rear gear. Drive it to work every day.
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