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Discussion Starter #1
Looking for solid flat tappet cam/ lifter/spring recomendations for apump gas oval port 468 10-1 compression, 2.25/1.88 valves, 049 heads, victor Jr intake. Direct lube lifters if it'll add some lifespan? 3500-6500rpm. What's the best grind for power that would still live awhile on the street?
 

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get the lunati voodoo cam 60202 it's .534 int .542 ex rpm is 1400 to 5800 it's a hyd, and it's mean i've got this cam in my 461 10.1 motor and my friends can't belive that it's a hyd you won't be dissappointed good luck killer 70 nova :p
 

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Discussion Starter #3
That's a lot smaller than I was planning to run, I bet you have some serious cranking compression- 200psi? I looked up the specs:
Advertised Duration (Int/Exh): 262/268
Duration @ .050 (Int/Exh): 219/227
Gross Valve Lift (Int/Exh): .530/.542
LSA/ICL: 112/108


I really think I'll want a cam with around 250-255ish at .050 duratiion to help crutch the oval port heads. I was originally planning on running a solid roller but I've chickened out-with my luck I'll lose a roller and it'll wipe the engine. I've had good luck with flat tappet cams in the past-never had one fail.

This one looks pretty good but I'd like to see more lift I think: http://www.lunatipower.com/Product.aspx?id=2138&gid=284
 

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that cam your looking into is nice, how ever look at a degree wheel and see where you are supposed to be making compression with it? I think you'll see that your not at 11.1 untill 5000 or better rpm range due to where the piston pisition as to where both the valves are closed !! Also you stated that you combo is at 10.1 !! think about the loss in compression at your lower rpm band this is going to make the motor be at about 9.1 with the amount of duration of that cam and also the overlap !! you'll see lunati recommends a 11.1 comp. due to the fact that down the lower rpm band you'll be at 11.1 then as you incress the rpm you should be at or close to 12.1 making real power up stairs!! on your oval port heads what is the cc of the chamber just curious and what is your deck hight? killer 70 nova :)
 

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Discussion Starter #5
The chambers measure 110cc, pistons are SRP small dome, I calculated the compression using all the variables includng the space around the piston above the top ring and it came out at 9.98-1. Pipemax program shows with a cam at 255 @ .050 I should end up with 180psi cranking compression which should work well on 93 octane I think. Maybe I should mock up the engine with a degree wheel and plot out where the intake closing point should be.
 

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i found that over the 20 yrs. of building sbc and bbc you can over cam an engine real quick! If you don't take the time to do the mock up and really get good numbers!!you just might over cam the combo and be slower than you thought you should go!! just some advise for you in your quest to go fast !! good luck killer 70 nova:cool:
 

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Discussion Starter #7
Yeah, I know what you mean. Have you ever done a compression test on your 461? Does it run ok on pump fuel? It must make some serious low rpm torque. Thanks for the input.
 

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Looking for solid flat tappet cam/ lifter/spring recomendations for apump gas oval port 468 10-1 compression, 2.25/1.88 valves, 049 heads, victor Jr intake. Direct lube lifters if it'll add some lifespan? 3500-6500rpm. What's the best grind for power that would still live awhile on the street?

Got a motor similiar to this, 781 heads, Performer RPM intake, it's got a .57x lift cam, adv 300, 300 duration. It's just a hydraulic cam, not solid. 1.60 60' times in a 5000#+ beast.
 

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go solid , we have a cool selection. pm if you need. nothing better than a real mech. bb cam , gets over 6000 rpm better
 

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my compression readings are not that scary but their up there my avarage is 190 my heads are aero head co. rec. port 2.25 int 1.88 ex it's the factory gm casting of the newer style head the chambers are at 119 cc and i had my bowls blended at my machine shop as far as running pump gas 93 is fine no problem but it does like the 110 vp race gas from time to time if you know what i mean good luck killer 70 nova
 

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Discussion Starter #11
Killer, those rectangular heads are ready for 7500 rpm+ I bet? Did you install the cam straight up or retard it some? Just seems like a really small cam for the rest of the combo but if it works it works! What rpm do you shift it at? I bet the heads help the cam hang on longer.
 

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The cam is installed strait up I was going to retard it but i decided not to do that because of what the degree wheel was showing me with my piston to valve relationship!!The heads come with .580 lift springs hyd or mech. How ever you like them of course!! I got the hyd springs they are set of isky's!! I also checked the installed hight numbers and the spring pressures they were right on with what lunati called for 120 psi closed and 320 open the valves are manley s/s the heads coast 1,000.00 shipped to my door!! the bowl blending coast me a six pack and some good jokes if you know what i mean!! i shift at 5800 right on the nose !! I have gone to 6200 a couple of times and didn't see anymore gains!! I will say this the tourqe of this cam comes on at about 2400 and pulls strait through to 5800!! I can honestly say it blows the tires off in every gear and also i'm running 390 gears in my ford nine inch !!! with sticky mickies on the back !! good luck killer 70 nova:)
 

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You might consider Comp Cams High torque 290 (255 deg at .050) intake lobe, 304 high rpm exhaust (266 at .050). Easy on parts, good power range.
 

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Looking for solid flat tappet cam/ lifter/spring recomendations for apump gas oval port 468 10-1 compression, 2.25/1.88 valves, 049 heads, victor Jr intake. Direct lube lifters if it'll add some lifespan? 3500-6500rpm. What's the best grind for power that would still live awhile on the street?
I ran just about the same set up, I was very happy with the Comp Cams 639in/ 639ex with a 270/280 duration at 50.I had thier triple springs with a plain solid flat tappet lifter. Very good response through 1/4 mile.
 

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Discussion Starter #15
I like the lift of that cam but 270/[email protected] seems like too much for 10-1 compression, weren't you at 12-1 compression with that cam? Bob
Crower has a cam picked out for me-I just need to confirm my parts are all in order and pull the trigger.
 
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