Thread: Cams choice

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As some of you know Im in the process (for the better part of 2 years, nickel and diming here and there) of building a big block 454 .030 over for my 66 Chevelle. I have spoken with quite a few people on here and always appretiate the individual help..Thanks much gentlemen. My lower end is done with a stock crank, stock rods, with upgraded rod bolts. Pistons are forged Ls6 repro's yeilding 9.75-10:1 compression. Im utilizing a set of 781 heads with street strip porting with larger stainless valves. Most likely a high rise dual plane intake, 750-850 or so cfm vaccuum sec carb, 2500-3000 stall convertor on a th400 trans and a 350-373 gear on 27-28" tall tire( carb, convertor and rear not determined yet). I am guessing when I say the car is approx 3700-3800 lbs with driver. Car will not be a daily driver, mostly street; occasional strip use, but need to have some street manners and run cool in Florida traffic.

So I was leaning heavily towards a hydraulic roller, but with flat tappet hydraulic Im already anticipating a 450-525 hp/ft lb motor.... without tubbing the car, so traction I would guess is already gonna be a feat. The added $ and hp of the hydraulic roller is just not necessary I think for what Im trying to achieve, so Im leaning towards hydraulic flat tappet.

So here is where it gets frustrating yet funny. Below I will list all of the cam recomendations I have obtained over the past 9 months or so. Funny thing is I give the same description to all whether they ask for it or not, yet some of these cams are quite a bit different from each other.

Please do comment! Comment on the ones you dont like, the ones you like or by all means suggest something different. Any input is much aprretiated by all experienced people on here. Thanks again to many on here who have increased my knowledge and taken time to reply before (Pat Mc, Johnny O, Tech etc etc)

Competition Cams (284 XE) (tech guy Robin)
240/246@ .050 574/578 110 LSA
3,000 convertor stall
AND/OR
234/244@.050 564/571 111 LSA


Crane Cams
226/236@ .050 534/553 112 LSA
2500 stall
AND/OR
236/246@.050 553/571 110 LSA


Howards Cams (tech Scott)
230/230@ .050 .514/.514 110LSA


Competition Products (recomended this howards cam)
228/236@.050 595/602 110LSA
3000 stall


Jegs (recomedned this XE274 Comp Cam)
230/236@ .050 552/555 (didnt give lsa)


Crower Cams
229/237@ .050 525/545 LSA 110


Lunati (voodoo cam)
241/249 @.050 572/590 LSA 110

AND/OR

240/245@.050 612/612 LSA 112
(both 2800-3200 stall)


Finally one of our experienced memebers recomended this Howards cam
234/240@.050 540/540 LSA 110

Now One I would like to throw out with my limited experience is the Lunati Voodoo cam
233/241@.050 551/572 LSA 110

Sp after talking to all of these companies, the person who made the most sense to me on cam choice was one of our members choice Howard cam. Regardless being a guy who just has not grasped and fully understands cam dynamics (I think beyond reading you have to have practical application experience, in several motors) I think most can see how frustrating this can be. I of course want to make a good choice/ and correect choice first time around. So, again please do comment, as they are all appretiated.

The majority of them are close enough on numbers that you would have to have them on a dyno to see the power differences. IMO, from dynoing a bunch of different combinations I doubt you would see more than 10 horse difference. On a street set up, no tubs, no slicks I would probably choose the mildest and hope it doesn't overpower the chassis and tires......

I run a Howards cam in my race car, and most the guy's running sprints up here are running them too. I've never gotten a bad cam or advise from them.

i spent some time with you. but i can not say for sure what i told you to run. but one thing you have to know or you will find out the hard way them big lift cam on small lsa will hit the pistons . have been there may times

Yes they will, you will have to cut the relief's in the pistons.

Wow Pat and Hambiskit,

Something I did not know or understand. Considering the hydraulic roller I was gonna go with why would this cam not hit which has higher lift than the flat tappet?

How can I determine what cam lift is gonna work without hitting the valves? And if I have to have valve reliefs cut into the pistons, how does one determine the depth?

a friend of mine has the crane 226/236. It is an excellent grind with a great sound and works well with power brakes. It may be a bit small for your application though.

Originally posted by 30-A Rider
Wow Pat and Hambiskit,

Something I did not know or understand. Considering the hydraulic roller I was gonna go with why would this cam not hit which has higher lift than the flat tappet?

How can I determine what cam lift is gonna work without hitting the valves? And if I have to have valve reliefs cut into the pistons, how does one determine the depth?

lift is lift roller or hyd flat. there is way to many thing that can hang you .like were is the valves in the head ? this is called drop heigth this may be very different now the heads have bigger valves . how much was cut off the heads? is the block O deck? and like i said the lsa has alot to do with this to and dura . there is no easy answer this is were you have to check all the valves on both sides of the engine