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Cam for my 67

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Dave2g

Member
If I were to get new cams, what should I be looking for? What are other things that I would have to do when buying/replacing them?

I don't really know what I'm doing for this either, is it easy do it yourself? I have some friends that know more so I could have them help if needed. I have a 289 4spd auto.

I don't know the current cams as the previous owner replaced them 15 years ago.
 
To make it less obvious you may want to refer to it as 'a' cam first, only one in a 289.
First off I'd try to avoid going too big/high on the lift you may end up with an overcammed motor that hardly idles at a stoplight. Be honest with yourself on what 90% of the use of the vehicle will be and pic a cam that matches that. With stock heads you want to pick a cam below .500 lift as once you get close to or over that lift the stock head studs begin to pull out as they are pressed in and aftermarket heads install screw in for this reason.

I'd start by downloading CompCams free 'camquest' program. You enter all the variables you know and it will suggest cam grinds in order matching your parts/needs. Your rear gear is most probably 2.79:1 and that's a safe number to put in as it will be around that with a 3sp. C4 trans. If you don't know some of the numbers when you get into the program ask, a lot of them are standard for a standard built motor. If it idles smooth now I'd figure they rebuilt it close to stock.
Jon
 
"Jonk67" said:
With stock heads you want to pick a cam below .500 lift as once you get close to or over that lift the stock head studs begin to pull out as they are pressed in and aftermarket heads install screw in for this reason.
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I would go a bit lower than that even with press in studs. I've had issues with lower lift cams. I think that faster ramp speeds on some cams, even with lower total lift, can cause issues.

If you are looking to swap to a new cam you can figure you'll need to replace springs, retainers, keepers and seals along with a new set of lifters. Stock springs aren't up to the task of higher rpm operation with performance cams. You should always get the recommended springs for the cam you select.
Given the age of the last time someone got into the engine (15 yrs?) I would pull the heads, have the guides addressed, have screw in studs installed and most likely new guides put in. You will likely need to install guide plates as well. All pretty standard stuff when stepping up to a new cam on an older engine.
Depending on the heads you have you might also have them milled a bit while you're at it. A bit of compression will certainly help with seat of the pants feel. If you have early heads with smaller combustion chambers probably not needed. And hell, while you're at it might as open up the ports a bit too! See how this gets going?
 
Judging by your other post, don't waste any money on the stock heads, go alum. as you appear to be planning to mount a supercharger to fee a roots blower and then pipe in a turbo to help on the exhaust side.
Jon
 
Am I suffering from lack of attention or did anyone else warn the O.P. about lift of over .500 with stock pistons??? If you do choose a cam with over .500 lift you risk the collision of your pistons with your valves unless you have replaced the pistons with flycut pistons that provide clearance for valve intrusion. BTW, if you don't know how many cams your engine has, you might not want to cut your teeth on a cam and heads replacement. Maybe that should be left to a professional mechanic or someone with a little more experience. It involves a lot of detail work including valve adjustment and, if you are going to re-use your rockers and pushrods, keeping them in order. I have a 351W cam in my 302 which has a different firing order that relieves stress on the lower end of the engine. Mine is right at .500 lift and it's a little lopey at idle but sounds really cool. Also, you probably also don't have a 4 speed auto. either, unless someone converted the car to a modern AOD. All the stock Ford automatic transmissions in the first generation cars were 3 speeds. If it is originally a 289 you probably have a C4, which Ford used for all their six cylinders and small V8s. Later in the first gen they added a couple of additional trannys to cope with higher torque engines, like the FMX and the C6, but, alas, they too were three speeds. This is not a slap at Ford. They had just emerged from the Ford-O-Matic 2 speed days when the Mustang was introduced.
 
I agree with your post to a degree, but a general blanket statement of .500 lift and you will have PTV issues is misleading. You should always check PTV, but cam events/timing have alot more to do with this than general lift. I have stock pistons in my 351w using Twisted Wedge heads. The lift will be .570ish intake 550ish exhaust and I'm not anticipating any PTV issues.

Bill
 
Add to that list of variables whether the deck surface of the block or the heads have been milled. How deep the piston sits at TDC. Also if you install the cam advanced or retarded will also have a huge bearing on your cam's designed timing events. A cam with adequate PTV can result in collision if installed other than standard (straight up).
I have spent quite a bit of time recently checking valve clearance on my new motor.
 
My dad has a 66 Mustang with a 306 (289 with 302 crank and .030" over). He has 69 351W heads(slightly bigger valves but not huge). Just port matched to the gaskets no wild port work. He runs a stock converter in a C4 and 3.50 gears. He has an Edelbrock F4B intake, 600 Holley and Mallory duel point distributor. It has 271 HiPo repop exhaust manifolds instead of headers. Really old school and pretty mild but he has a Comp Cams 268H cam. The thing will break the tires loose on command, chirp them when it shifts into 2nd and it's a blast to drive. I helped him build the motor when I was in high school and it has tons of miles on it, very reliable. Still has the rail rockers, no studs in the heads, etc. It's all out of breath around 5500 rpm but on the street that's plenty. He installed the timing gears straight up, stock bottom end, nothing fancy. It's just a fun little car!
 
"tarafied1" said:
My dad has a 66 Mustang with a 306 (289 with 302 crank and .030" over). He has 69 351W heads(slightly bigger valves but not huge). Just port matched to the gaskets no wild port work. He runs a stock converter in a C4 and 3.50 gears. He has an Edelbrock F4B intake, 600 Holley and Mallory duel point distributor. It has 271 HiPo repop exhaust manifolds instead of headers. Really old school and pretty mild but he has a Comp Cams 268H cam. The thing will break the tires loose on command, chirp them when it shifts into 2nd and it's a blast to drive. I helped him build the motor when I was in high school and it has tons of miles on it, very reliable. Still has the rail rockers, no studs in the heads, etc. It's all out of breath around 5500 rpm but on the street that's plenty. He installed the timing gears straight up, stock bottom end, nothing fancy. It's just a fun little car!
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tarafied1,
does your dad's car have a noticeable lope with that cam? I installed that in my 289 with fully ported gt40 heads. I haven't fired mine up yet... just wondering how it sounds at idle. I figure it will be slightly noticeable with the 110* lobe seperation.
 
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