NEED HELP PICKING A CAM

Well i finely decided to rebuild my 69 Mach1 drag car . It's been sitting @ 15 years . It's a 502 I built @ 30-35 years ago , has a offset ground 460 crank , 40 over bore with big block chrysler alum rods . I'm running iron cj heads with aftermarket springs and valves . Ran real good with a comp flat tappet 310b cam but going solid roller this time . Need help finding a cam to help crutch the factory exhaust on these heads. Any help is appreciated . TIA !!!!

Ken A. wrote:         Well i finely decided to rebuild my 69 Mach1 drag car . It's been sitting @ 15 years . It's a 502 I built @ 30-35 years ago , has a offset ground 460 crank , 40 over bore with big block chrysler alum rods . I'm running iron cj heads with aftermarket springs and valves . Ran real good with a comp flat tappet 310b cam but going solid roller this time . Need help finding a cam to help crutch the factory exhaust on these heads. Any help is appreciated . TIA !!!!

Is this a "drive around" street car, a street/strip type car or a race car ...?

Drag only . 3000 lb Mach1 , running factory iron CJ heads with old aftermarket valves and springs . Springs are junk from sitting compressed so long . I figure they'll need everything to bring them back . Don't want to port them because i don't know what I'm doing and don't want to ruin them ! I know it's Thanksgiving so everyone have a great day and hopefully I'll hear from you tomorrow .

Tell about your trans. and convertor gear ratio compression ratio carb. and intake .What does it weigh?

3000 lb 69 Mach 1 , 71 cj c6 , 5000 stall , 456 gear with spool , @ 12.5 compresson , weiand tunnel ram , 2 - 660 .

That Comp 310B8 is a pretty heathy SFT camshaft showing at 275/276 at .050" lift duration in the old CompCams book. Basically a single pattern camshaft.

The Kaase K1 low lift version in 5Pointsslow 509 with Eddie heads did very well in my opinion.

Maybe some 1.8 rockers on the exhaust if you want to crutch for the manifolds, for a non custom cam.

https://www.429-460.com/t29173p50-motor-is-going-on-dyno-next-week-want-to-guess-the-hp

The spec.'s are toward the bottom of page 3

Good Morning, speaking of camshafts, supervel45 did you get my message ?

I guess it was full. Check your box, I sent you the spec.'s.

Thank You supervel45

On my Mach 1 , I have a Alston frt sub frame and a custom set of 2 1/8 inch headers . The exhaust port flow is the problem . With the tunnel ram , cam and alum rods that were in it , it RPM'ed quick and high . Just trying to make it quicker this time around .

Just looked up the 310b cam on comps site and this is the one I think I had . 429/460 solid flat tappet marine /drag ,4000-7000 rpm ,intake @50 270 / exaust @50 276 .Intake valve lift 0.656 /exhaust valve lift 0.641 .

Supervel45 , Thanks for your response and help!!

Randy, if you need any more information just let me know . Thanks for help!!

Ken A. wrote:  Randy, if you need any more information just let me know . Thanks for help!!

I am curious to know why you don't use a better cylinder head. Is it just a personal thing ...?

How much valve lift will your cylinder heads, (not the valve springs), accept ...?
What is the obtainable spring installed height with your heads ...?

Ken A. wrote:   Just looked up the 310b cam on comps site and this is the one I think I had .    429/460 solid flat tappet marine /drag ,4000-7000 rpm ,intake @50 270 / exaust @50 276 .Intake valve lift 0.656 /exhaust valve lift 0.641 .  

You're welcome.

The spec.'s I quoted where from an old 1992 Comp catalog for the 310B8. I have noticed that Comp has changed their spec.'s for the same grinds in the electronic online catalogs. I don't know if the actual grinds got changed to reflect the new numbers though. They may have misprinted the numbers in the paper catalog also. The lift showed .649"/.641" , advertised duration of 310/314 degrees.

I must have misread your other thread, I thought you had CJ exhaust manifolds.

If those were my CJ's and I was not worried about molesting them because of the value, I would look into removing or reducing/profiling the exhaust air bumps.

Randy, I appreciate all your time and help. After calculating what It's going to cost to get my iron heads ready to use, I'm thinking I should just sell both sets of my iron cjs and buy some good aluminum heads and pistons. When I figure out what heads I'm getting I'll give you a Holler and see if you can help me out with a cam. Thanks for your time and help!!

Several years ago I swaped my iron cj heads for a set of edelbrock cj style heads .The iron cjs had exhaust porting bowl blend in and ex a smaller coumbustion chamber .The edelbrocks were three tenths quicker .Everything else was the same .Not saying you should get these heads but you get the point.

Ken A. , How much power are you looking for or what time slips do you want to achieve ?

Randy I understand what you're saying and it really doesn't make sense to put a bunch of money in the iron heads and not go faster so I think I'll sell my iron heads and find some good aluminum ones. 80CapriBigBlock . I'm probably @ 500/600 hp now , runs low 10's @130 mph . Just looking to get all I can out of this thing. Probably going to find some p51's and put pistons to match, then figure out the cam .

What is your tire size, trap rpm and what is the number you want to run ?

Tire size I think is 13 32 15 . I was running 456 gear which was too low ,so I was running out of gear @1000 ft . This time I'm probably going with @ 411 . Trap rpm will depend on heads and cam . My rear suspension was junk but we're redoing that also. Everything is going to be different so I'll just have to wait and see. When I figure out what heads I'm going to use I'll come back and see what everyone thinks cam wise. Thanks to everyone for the help!!!

What was your rpm at a 1000 ft if that is where it ran out at ?

Seems like it was # 6700/6800 , but that was along time ago.

The converter is loose and giving up 400 to 500 rpm is the problem not the gear. So what do you want the car to run before you start buying 7 grand worth of parts for it ?

Probably @ 9.50 /9.90 . I bought the converter and a valve body from Art Carr @ 35-40 year's ago. Have no idea what it actually was , but on the t-brake it stalls to @ 5000 . Lost all my paperwork in a fire year's ago .