Advice on what cam I need
#1
Advice on what cam I need
Hey gearheads, want opinions on what cam I need to install in my engine before it gets rebuilt. I have a 72 Charger w/ a original 400 in it. Still runs good (a little sluggish on start up from a stoplight, probably needs alittle more fuel) but I'm restoring the car and might as well do the engine over. It has 102K miles on it. Originally had a 2 barrel from the factory. Previous owner put an 750 Edelbrock carb on it with a Edelbrock Performer RPM intake, super comp hooker headers and dual flowmasters, but he didnt change the cam. I would like to change it to a cam that works well with the existing carb/intake/exhaust setup. The car will NOT be raced on the strip. The rear end is only 2.45, but probably be changed at a later date. Tranny is a 727 Torqueflite and has already had a soft rebuild done to it with a new converter installed. I'm guessing a mild cam so I don't lose too much idle, I just don't know what the cam specs should be. I know it probably won't rumble like I want it to, but I don't want to sacrifice low end acceleration and torque. The flip side of the coin, since I'm going to change the rear end ratio at a later date, perhaps I should go with a more aggressive cam? Any ideas. Thanks DGB
The following users liked this post:
dgbcharger (03-28-2014)
#3
440HP would be a good choice, another slight upgrade would be a switch to 1.6 rocker arms or maybe a 6 pack cam.. Make sure to get the correct timing chain 6 pk as I remember has a 3 bolt cam setup.
Needs a gear change now rather than later. 2.45 may require changing the speedo drive housing when you do the swap
Needs a gear change now rather than later. 2.45 may require changing the speedo drive housing when you do the swap
Last edited by TVLynn; 03-27-2014 at 07:05 PM.
#4
IMHO the carb is close to being to big. but if you use the cam listed by TVLynn the 750 carb will be fine. just remember when tuning the carb change the the jets OR the rods NOT both at the same time. best to change the jets first, then the rods. remember a little is a lot. a change as small as .003 will make a change. and a .003 change on the jet is a bigger change than the same change an the rod. after a change give it a day or two to see if you like it. do NOT force the jet taking it out. if they in real tight there is a trick to get them out. and they dont need to be put in tight, just snug is fine.
#5
HP cam is a good choice, 6 barrel cam has too much duration for your compression.
Have a look at: http://www.compcams.com/Company/CC/c...?csid=706&sb=2
Have a look at: http://www.compcams.com/Company/CC/c...?csid=706&sb=2
The following users liked this post:
dgbcharger (03-28-2014)
#8
2.45. rear end. Are you sure? Did they really make such ratios back then? You get no real fuel economy with that, as your converter will be slipping like crazy most of the time. If you like high speed driving, I would go with a 2.76 or 2.94. If you wanted some city driving thrills and willing to sacrifice high speed smoothness and top speed, you can go to 3.23.
I have recently replaced the cam on my 68 440 (see 440 build for Imperial). I also got larger valves and mild porting, but retained manifolds. The cam I selected is 0.477 intake lift (stock 440 HP was .450) but total duration is identical to HP. I am just now doing the initial test driving, and low end torque seems fine. But your 400 8:1 compression may be a different story. But then again, you will go in the engine shortly, so you could replace the pistons for 10:1 or 10.5:1.
I have recently replaced the cam on my 68 440 (see 440 build for Imperial). I also got larger valves and mild porting, but retained manifolds. The cam I selected is 0.477 intake lift (stock 440 HP was .450) but total duration is identical to HP. I am just now doing the initial test driving, and low end torque seems fine. But your 400 8:1 compression may be a different story. But then again, you will go in the engine shortly, so you could replace the pistons for 10:1 or 10.5:1.
The following users liked this post:
dgbcharger (03-28-2014)
#10
If you are saying that to me, yes, just replaced the 10w30 break in oil with 20w50 mineral plus ZDDP. That will stay there probably through the summer, and then back to my Mobil 1 ...
dgb charger, you may consider replacing these headers back to manifolds when you take the engine apart. I do not think the headers will do much under 4500-5000 rpm, other than being noisy and cook everything under the hood.
dgb charger, you may consider replacing these headers back to manifolds when you take the engine apart. I do not think the headers will do much under 4500-5000 rpm, other than being noisy and cook everything under the hood.
The following users liked this post:
dgbcharger (03-28-2014)
#12
Moe7470, Thanks for the info. I already have the next size up rods & springs from Edlbrock so I'll probably try them first but it's still a ways off. I'll order new jets any way. Thanks again. DGBcharger
Last edited by dgbcharger; 03-28-2014 at 07:43 PM.
#13
demertri, Yeah I'm sure, there is a metal tag on the cover plate bolt that says 2.45. Its an 8 1/4 rear end with 10 bolts. Thanks for the info.
Last edited by dgbcharger; 03-28-2014 at 07:44 PM.
#18
Repeating what Mr. 4spd said. HP = high performance, this camshaft came out in 1967 440 I believe. One of the best stock cams out there.
Comp Cams has a program called Camquest that can recommend cams with your input.
If you look at any of the cam suppliers they have loads of info on cam basics.
Just for giggles I ran your with the XE 262 H and came up with 331hp and 436tq.
Comp Cams has a program called Camquest that can recommend cams with your input.
If you look at any of the cam suppliers they have loads of info on cam basics.
Just for giggles I ran your with the XE 262 H and came up with 331hp and 436tq.
#19
yep Bob you do have great friend here. i would like to think they are my friends to. i have been to some other sites. you will note i went to them but didnt stay there. this is one of the best sites i have seen.
Thread
Thread Starter
Forum
Replies
Last Post
TwistedWrenches
Do-It-yourself Section
5
05-16-2009 11:51 AM