340 Cam Kits which ones work with a stock block
Looking for a good cam kit for my stock block 340 with stock exhaust manifolds and stock intake but willing to change the intake if need be. What I'm looking for is a cam kit that will give me the nice cam sound but don't want to sit at a light and rock and roll, want to be street able. I know I will have to change springs and rocker arms and lifters not an issue. Car does have a 2 1/2 " TTI exhaust system all the way with dyno max mufflers. She is a automatic with a nice shift kit but not sure about converter. Rear end has 3:91 posi.
I have no idea what's in the car for a converter, what ever is in there was there when I purchased the car last year. Do I really want to drop the tranny to change the converter, if I was going to go to the track every weekend I might but I have no intensions of going to the track. Just play around on the street so no
It's a stock block X head motor with a production date of 6/22/67, stock compression 10.5.1
The stock 340 cam has a Intake lift of.429 and exhaust of .444 according to my service manual. The cam I'm looking at is a purple shaft with a Intake and Exhaust lift of .484 or a cam from another manufacturer with something very similar
Wyrmrider/Crackedback
I was going to wait till tomorrow to do a compression check but since it's so crappy outside I went ahead and pulled all the plugs. This is what I have, mind you this is a stock block X head motor that's never been apart. Cylinders 1,5,7- 155, cylinder 3, 150 cylinders 2 and 4- 150, 6 is 148 and 8 is 155 so the compression doesn't look all that bad.
Crackedback after talking to a buddy of mine he told me that the .284/.284 .484/.484 would be to much so I'm still looking but I have been on Hughes Engine website and submitted a form with all the info they requested for a Cam kit and I did the same with Howards Cams. I'm also going to talk to a guy by the name of Dwayne Porter who is a very good mopar guy and I'm waiting for a call back from Scott Brown from Competition Components. One way or another I will get the right setup
The cam kit that the Coronet had worked very good but I'm looking for a idle a little more choppy over stock. The coronet idle was very mellow
Average cylinder pressure of 152.5, which you call; "so the compression doesn't look all that bad", by itself is barely Ok for whatever is in it now. The only thing that is saving your combo is the 3.91s, and possibly the TC as we don't yet know the stall.
So whatever cam you chose it is gonna have to be custom, and you are gonna have to figure out first, one of the following;
1) your exact compression ratio, or
2) the exact ICA of the current cam,
3) both would would be ideal.
From those numbers you can build a cam.
Without those numbers anything you put in there is a gamble, and is likely to turn your bottom end to slush, mandating a new TC. And then your fuel economy will take a dump as well.
Unless your low cylinder pressure is already the result of a big cam.
So I highly recommend a LeakDown test to prove the numbers are NOT due to leakage.
Without some kind of idea as to what's in there .... IMO, you could be setting yourself up for an expensive disappointment.
From what I'm seeing, that engine is already a candidate for being a soft combo.
Those early 340s in stock-tubbed As,with street tires,are tire fryers all the way thru first and a good ways thru second to something like 60 mph,often even higher. How does yours compare?
