oldkimmer said:
I have built a lot of small blocks and comp is by far my cam of choice. 9 times out of 10 the best cam for the little 273 is the factory 340 replacement muscle car cam, it has the slight rumble that everyone loves. I would be more inclined to go with the xe256 if this is an auto car, with a stick u could get away with the 262, but the 268 will lose that all important torque that we all desire....ofcourse it will sound pretty mean+idle choppy, just like the chevys....all show and no go........kim
OK thanks for the info. I hope you will answer some questions for me since you have built a lot of small blocks. I feel confident with your knowledge since you have done this before.Where I am at is that I'm not sure what compression I am running. You might have read some of the posts I have placed and can tell that I'm confused on what to do at this point. You might have seen the other thread also:
http://www.forabodiesonly.com/mopar/showthread.php?t=14094
Engine and other info. Headers, Flowmaster 40 mufflers,Accel 300+ ignition(multi-strike) with spark plugs gapped at .40,performer intake,eldebrock 500 cfm carb.
Ok the first question is since I don't know what compression raito I've got will the XE262 be ok to run? I have the 4-speed trans. I would like a choppy idle rather than a rumble. I feel like I had a rumble and that is why I am changing cams. It was to stock for me. The specs on the cam that I have removed are Duration @ .50 is 204 and the intake lift is .420. The whole spec sheet is above in one of my posts. If I go with the xe262 I will have 014 more duration @.50 and 042 more lift. This is just on the intake side. So with not knowing what compression I have do you think that this will be ok? I was dead set on the xe268 but now since I've read your post I've backed out. lol Will the xe262 have a choppy/radical idle you guess? I was going to pull the heads and have them shaved a little to get the compression up but I don't want to have problems with the push rods (non-adjustable rocker arms)and the intake not matching correctly. Which ever cam I go with I am going to get the whole kit cam,lifters,springs,retainers,valve keepers,seals, timing chain (I had a single not a double).
Ok the second question I have is that Hughes Cams says that anything over .450 lift that I would have to shorten the valve guide hieght because the valve retainer will hit the valve seal. I was wondering if you had to ever do this or know for sure that I will have to have them shortened? One fellow has posted that max .490 and not to worry about that. I will measure that when I get a chance just to make sure. Outrageously Vintage says that what I need to do is take the spring off one of the valves re-install the retainer and valve keepers and measure it. The rule of thumb is .040 extra clearance than cam lift. But I'm not exactly sure of the cam I want. If you think that the xe262 is the cam I need to run then the lift is going to be more forgiving and then I can go from there. I just hope that the idle is what I like.
I'm ready to get her back together but want everything to match, perform, and sound good. I would hate to overlook something while I've got it apart and wished I had done something different later. I would hate it also to have the same idle sound as I did before but it would probably would be up on horsepower/torque some because of the added duration and lift.
