What is a good slightly bigger than stock cam I can put in a 1963 401 without having to change lifters or push rods?is it possible? I want the thumpity thump sound. Suggestons tips?
What's a good budget combonation for a cam and lfters. I'm aware that these cams are big stock so I don't want to end up with an aftermarket cam that is actually smaller. Also what's the cam break in procedure for this 401. ---------- Post added at 10:23 PM ---------- Previous post was at 10:22 PM ---------- What numbers do I look for?
If you want the thumpity thump sound then the cam needs to have at least 15 degrees of overlap using the .050" spec. Here is the Comp Thumpr cam in action. It has 20 degrees of overlap. http://www.youtube.com/watch?v=DYBzfLgSTOE Here's are few things to consider with a cam that has 20 degrees of overlap The intake manifold vacuum is marginal for power brakes. It works best with long tube headers. The scavenging effect from the headers helps pull the intake charge into the cylinder during the long overlap period. Makes for a strong midrange. Requires a lot of initial timing, 20 degrees or more. The distributor mechanical advance range will need to be shortened. A 2500 stall torque converter. Frequent trips to the gas station. Paul
if you are looking for gas mileage,, a plain stocker or a stock 091 cam will do that..... the 091 is the old stock super wild cat cam....
Like Paul said, if you want the "thumpity thump" sound, the Thumpr is a good choice. That's actually my '62 in the video he posted. It isn't the easiest cam to tune, but it's certainly doable. It has enough vacuum for power brakes, providing you have a vacuum canister. Otherwise everything that Paul mentioned was spot on. You can get the Thumpr and lifters as a package deal for pretty cheap if you look around. If you don't want something as radical, look at the TA-25 from TA Performace. It won't sound like a Thumpr, but it'll be a really nice street cam. Another option is to have a cam custom ground. Perhaps similar to the TA-25, but on a 108* LSA to get a little more lope. In terms of breaking it in, make sure to use plenty of assembly lube and a break in oil additive. Comp Cams sells both. Otherwise it's just like every other cam break in; start it up and vary the RPMs for 20-30 minutes, and change the oil right after.
yep,,,been thrashed a bunch.... just check out the old 091 cam and either get one of those or as close to it as possible.... and it will be good.....
Will the 091 cam require new lifters/pushrods or change them out anyway since I would already be there.
any, any cam new or used will require new lifters.... your pushrods and rocker arms will work ,, if they are in good mechanical shape..... just dont ''over cam'' it....that is the most common mistake.... the other most common mistake is building and not replacing the old cam bearings....that,,, guarantees low oil pressure from the git go.....
Andy Nice job tuning your engine for the Thumpr cam. I know it's a lot of work and it sounds great. Your Idea of having TA grind the TA-25 on a 108* LSA would work well for someone that wanted a lopey idle and still have plenty of manifold vacuum. It would have 7 degrees of overlap versus 20* for the Thumpr. It would definitely be one step up from a stock profile and with the tight LSA would offer a lot of midrange power. Paul
I don't know if there are any new 091 cams left. I may have gotten the last one, and it's not for sale. I intend to install it in my 425 this year. The specs have been published here - a little digging will probably find them. As has been said before, any cam, old or new - must have new lifters. Listen to Doc. His advice is good.
