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Post by akwhtbst on Jan 4, 2011 11:12:17 GMT -9
So I'm thinking of going with a different cam in my engine this year. My engine specs are... 350 bored 40 over, 11.5 compression, steel crank, brodix track one heads, 2.08 intake and 1.60 exaust valves, Harland sharp roller rockers, head studs, main studs. This is my current cam, www.summitracing.com/parts/CCA-12-990-9/, it was chosen for my prior car that weighed about 4000 pounds. This car I'm building should be 2700 max. I'm thinking often with this cam, www.summitracing.com/parts/CCA-12-906-9/What do you guys think? Will I gain much from this cam swap? Thanks Tim |
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Post by 9secondsatellite on Jan 4, 2011 17:30:01 GMT -9
more info would actually help in the equation. what intake,gears,tire size,stall rpm. definitely raises your rpm range but if the rest of the equation was built for the lower rpm, you might not see much of a gain. it will also depend on the flow numbers of your heads.
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Post by akwhtbst on Jan 4, 2011 17:51:45 GMT -9
I have the flow numbers on the heads at home. Or at least wha brodix claims they flow.
Stall is 4500, tire size is 28x11, gears have not been bought but will be either 4.56 or 4.88, the intake is a ported Holley airgap.
I'm putting this engine in this car with nothing else it ran with before in the heavier car. Different tranny, different stall, different carb, different rear axle, only this is the intake is the same.
Hope that helps and thanks.
Tim
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Post by semi serious on Jan 4, 2011 20:31:37 GMT -9
Tim,
More duration and a higher operating range sounds good but the first place you may want to start is finding out what the rating of the valve springs are in those Brodix heads, how much lift can they take? Looks like you are planning on sticking with the same .630 lift but if you go with your 1.6 rockers you will end up at .672 lift and even a little more duration as well. The intake seems like it may be on the light side for this rpm range too. Maybe a Victor, Super Victor, Hurricane, single plane style instead. They wouldn't choke off that cam past 6500rpm. And since you're launching at 4-4500 you won't need much for bottom end torque anyway. A call to Howard's or most any other cam manufacture will net you some valuable free advise as well.
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Post by akwhtbst on Jan 4, 2011 20:45:05 GMT -9
I'm stuck at .630 lift due to my pistons. I don't want to change those out or have them machined to clear the valves if I go with a larger lift cam. This motor will only be in the car for this summer, I have plans for something better the following season.
The intake I have is a single plane intake that's been hogged out. Jay Goodie knows my intake, it came off a 327 he use to own.
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Post by 9secondsatellite on Jan 5, 2011 9:14:27 GMT -9
sounds like you should be okay, but the intake might be a bit suspect. like semi serious posted, you should look into your springs because you are winding it up faster now.
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Post by ProStreetNova on Jan 5, 2011 11:31:09 GMT -9
I like your second choice, more duration.
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Post by akwhtbst on Jan 5, 2011 11:41:28 GMT -9
I like your second choice, more duration. Do you think the second cam will make a big enough of a differance to be worth the money for the new cam? Thanks for your input. Tim |
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Post by 9secondsatellite on Jan 5, 2011 14:04:45 GMT -9
what state of condition(how many passes)is your engine in now? if you are just changing cams and nothing else in the engine and the engine has several passes or close to needing a good freshening up, i wouldn't change cams at this time. you are already changing a bunch of stuff as it is. if you kept the engine the same then you already know what you have. that way you can see/feel the difference in going to a lighter car with different transmission, different stall and different gearing. if you change too much you might not know what made the difference or what possible gremlin you could be chasing. just a thought.
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Post by akwhtbst on Jan 5, 2011 14:15:34 GMT -9
what state of condition(how many passes)is your engine in now? if you are just changing cams and nothing else in the engine and the engine has several passes or close to needing a good freshening up, i wouldn't change cams at this time. you are already changing a bunch of stuff as it is. if you kept the engine the same then you already know what you have. that way you can see/feel the difference in going to a lighter car with different transmission, different stall and different gearing. if you change too much you might not know what made the difference or what possible gremlin you could be chasing. just a thought. That is a very good point.... The engine has about 20 passes on it so it's rather fresh. I'm glad you brought that up, I think I'll leave it the way it is now and run it. That way I can see the differance all the changes make. Just in weight saving I should shave 1.2-1.5 seconds off what it ran in my other car. I think it has more too with the tranny and convertor change too. Going to the track I'm sayin it will run 10.0 and if it goes faster that will be great and I'll get the engine diaper then. Thanks Tim |
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