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Hello all. Did some digging about this on here and all the answers seem very...specific. I'm going to be swapping out the heads on my '67 289 this winter. The engine is damn near completely all stock and original. So the heads have the " lead gas" exhaust valve tick and etc. Planning on just a set of late 80's 5.0 heads as replacements. But figured since i'll have things torn apart, why not look at some other aspects like the camshaft. I'm really not aiming for loads of power, but I absolutely love that old pure muscle car lobe that a larger cam gives you. And thats what I would like to have. But I know that normally if you change one thing, you have to change another. So asking for some "big picture" thoughts and good ideas for the cam...
Thanks
 

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Lots of options out there, the wallet and your level of willingness are the key. Honestly you'd be money ahead to just get a set of modern aluminum heads, and as long as your into it that far.....why not just freshen up the whole thing? See what your compression looks like - but new rings and bearings will go along way to longer life. Be sure to use correct additives/oils for it afterwards! (ZDDP or racing oil like VR1) When you start messing with cam profiles you will have to of course adjust the valve train accordingly - different pushrods, springs, etc....or you can look for a kit that is ready to go - including heads, which is another good way to go. Another good argument is to just get a crate motor and be done with it. Depends on what you really want in the end. A crate gives you drop and go funtion with a warranty in most cases.
 

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watch the head swap, GT40P have small chambers and flow great, late 80's heads will probably drop your compression a point or 2. There are a lot of good cams, call any supplier and they will help you. It will have to be a mild cam depending on you axle ratio and torque converter assuming you have a automatic. Just don't go above .490 lift and you can get by with your stock valve springs, maybe something with a power band around 1500-5000. Your heads should be ok, as long as your not drag racing all day. I have been running engines for years without hardened seats, I use a lead substitute additive with no problems.
 

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Cams.....The bane of my existence! You are right, in that when you change one thing, you will need to change another....Your wallet will be your guide on this. when you get to .500 and more lift, you need (in broad terms here...) a new torque converter if it's an auto car, new rear end gears, dual exhaust, better ignition, good carb and intake. Plus, if you aren't sure about the bottom end, now is the time to make sure. Depending on machine work costs, you can still build an engine for around 1500 bucks. Fresh compression does wonders, as well as new rear end gears.
"Speed costs money son, how fast do you want to go"?
 

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"Speed costs money son, how fast do you want to go"?

Not much more needs to be said!:ylsup:
 

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I'm with Bad69cat on this one. The most bang for the buck available is with a decent set of aluminum heads. Put in a decent street/strip cam, intake, carb, and exhaust and you've an incredible jump in performance. Of course as others mentioned you'll need to upgrade most everything else, but you don't have to do it right away.

With out a lot of work, if the motor is breathing right, you could expect 1 HP per cubic inch.

Good luck
 

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Check out those Comp cams Thumper cams. THey claim to give a lopey idle and maintain alot of the cars driveability, specs on these look pretty good too. I think rpm range is in the area of 1500 to 5500. Not bad.
 

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If you aren't getting aftermarket heads, at very least get a set of better than stock rocker if you are doing the cam. I had a cam in my 289 with a .410 life @ 260 duration, and after about 2000 miles I stripped it apart and found that the lift ate the ends of the rockers off at the stem. Things might have gone badly if left longer, so its something to consider when you go with a big cam.
 
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