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Discussion Starter #1
Doing my build, going with single pattern cam just not sure what i will get from it and looking at two choices. sbc 355, Vortec heads, edelbrock performer rpm intake, cam choices #1 duration 268/268 lift .477/ .477 #2 duration 284/284 lift .480/ .480 can anyone tell me what i can expect power, performance and fuel wise
 

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if those vortec heads are stock, I'd be sure and check all the clearances REAL close! you are awful close to spring/rocker arm interference with either of those cams

:???:
 

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any hyd cam with more than 450 lift you will have to have the guides cut down and use different valve seals- now with a roller its a lil different you can get more lift in under the curve, however $$$
ask me how i know:secret:
 

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I am shooting for 9.5 to 1 no more than 10 to 1 the heads are aftermarket Patriot Performance Vortec and 750 carb
 

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Ok so now I know all most clear as day what type of compression I will have, thinking sbc 355 with 9.3 cr Performance Vortec heads, edelbrock performer rpm intake, quadrajet, headers, with cam choices #1 duration 268/268 lift .477/ .477 #2 duration 284/284 lift .480/ .480 can but if I get to feeling good I might run it up to a 383 with 9.9 cr with the rest being the same. Hope I have enough info to get some good feed back.
 

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A) A lot of overlap in a cam will lead to some cross breathing and reduce the effective compression ratio, so you might consider going up a half point in compression.

B) I question why you'd ever buy a single pattern cam when a dual pattern costs just the same? Buy a dual pattern cam that is about 220/230 @.050 and you'll be happier than you would be with single pattern. Buy a hydraulic roller and you'll be even happier. Which ever cam it is , stay away from short lobe centers. You want about 112 degree centers. Anything much lower kills vacuum and driveability.

C) Headers, Large port intake and big cam means you better have a high stall converter, low rear end gears and a good gas credit card.
 

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With the 284 cam i had about 7on the vac had to put roads lifter to get 16 now i have vac for brakes with 12.5 pisions turbo 350 342 rear gears about 5 to 6 miles per gallon I also have a 750 cab.
 
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I'm running a 292 Comp cam and I have to say,the bigger the cam,the more stall is gonna be needed. The 280 might be a better choice for you to run a stock torque converter. Are you using a TH350 trans?
 
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