455 cam theory

[G-Body_Vet]

I just happened to stumble across this old thread and decided to dig it up once again.....especially since the cash situation has improved in the last 3 years :lol:

I came across a bone stock '74 455 myself and I'm really tempted to put a new cam & lifter set in it while it's apart. I don't expect much for the stock low CR, but now would be a good time for a slight upgrade if it's worthwhile.

 

[online170]

The advice in this thread is sound. I think Bonnewagon was on the right track.


I would say the factory did not pick the best cam. They had emissions regulations to contend with, and insurance companies to satisfy.


You can go quite a bit higher on the duration before you start getting into overlap. If you avoid overlap, you avoid bleeding compression off.

All that to say, I would go with the most lift and duration without getting into a lot of overlap, because compression will make a big difference in how it performs.

 

[Bonnewagon]

Steve, I am glad you dug this old thread up. I am a little closer to using the 455 in the wagon, since it sits around a lot lately, and the rare road trip would not bother me as much now. I do have some experience with the "068" cam, my buddy had it in a '68 Firebird 400 and it was a revving beast, with just an acceptable idle. The 455 should calm the idle a bit, but it would never need to rev as the 400 liked to. That's why my whole idea was to limit the duration to what a stock 455 is comfortable with, and give it lots of lift for all the low-end grunt as I can. I guess my question should have been, "what is the best street cam for a totally stock 455?". And before I yanked the 455 from the GrandVille, it lit up the tires without even trying hard. Perhaps I should try it as-is, and decide later?

 

[G-Body_Vet]

I guess my question should have been, "what is the best street cam for a totally stock 455?". And before I yanked the 455 from the GrandVille, it lit up the tires without even trying hard. Perhaps I should try it as-is, and decide later?

That's pretty much what I'm looking to do. I'd like to run it as is with just freshening up a few things. The only reason I'm contemplating the cam & lifter change is because a few cam lobes are worn differently from the rest. When I get a chance I'm going to pull the lifters and see what the wear pattern looks like. I've read a lot of different cam opinions from the Melling SPC-7, Summit 2801, Comp XE268-H, the factory"068" etc.

Ideally, I'm wanting something compatible with the stock CR and valve springs. I plan to swap my 3.73's for a set of 3.08's I already have, then just use a TH400 for the time being. I'm really trying to avoid the "fix all snowball" from gaining momentum again :lol: