Newbie here with a few questions. I have a 68 coupe with a stock 65 289 and was wanting to put a different cam in it. I have posted on ohter sites and gotten a little help. I was wondering how much lift and duration could these motors handle without having clearence issues such as piston to valve and so on. I plan on changing the springs along with the cam and lifters and reuse the rockers and pushrods. Someone said that around .520 lift was the magic number to stay under. Another question is there some info i can get on a set of headers that will work on this car , it is a manual shift. I'm in the same boat as everyone else these days and on a budget and want to thank you for your help in advance
THANKS

 

I'd recommend the Comp Cams XE256H, kit # K31-234-3. It should still operate any vacuum-powered accessories you have (or may add later), and it won't overstress your engine. The limiting factors for the cam are your factory rod bolts (which I wouldn't spin past 5500, if that) and valve clearance. .520" lift is too much, IMO. You risk piston contact at that point, and you're also more likely to pull one of those pressed-in rocker studs out. The XE256H will give you a nice boost in usable power without worrying about breaking anything.

Make sure to check your pushrods to ensure they're straight. Roll them on a piece of glass and look for any wobble. Pushrods aren't that expensive, so replace them if they're bent.

 

Hey thanks for the cam help do ya have any info on a set of headers that will work on this car with a manual shift? Shorty or long tube im not real picky on this.

 

You will have less obstruction issues with shorties. Also, think about switching to the H.O. firing order when ordering your new cam. The newer firing order is less stress on the 289/302.

 

Eh, it's not that big of a deal, and it's easier to find a stock-improvement style cam with the original firing order than with the 351W firing order.

I do agree about the shorties, though. They'll fit in easier and they're fine for your engine.

 

Thanks starfury for the info, i was looking at the crane 364381 it has 288 duration and .488 lift whats your opinion on this cam