comp cams extreme marine

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Does anybody know anything about the comp cam extreme marine product? Was wondering if anybody used them or if they are a good choice.

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i've got a bbc with o49 heads 1.88 and 2.15 valves

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i've got a bbc with o49 heads 1.88 and 2.15 valves

[Daytona100]

Whats your compression ratio?:idea: Mike

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9.5:1

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are these things junk? or are they an ok aftermarket product?

[Daytona100]

You can order a camquest disc from comp cams pretty cheap. You put in all your stats and it tells you what cam to use and a dyno graph.:D

[DUCKY]

I put an XM286 in my Dad's motor two summers ago and it has been great for his application. The motor is 525" with Edelbrock Perf. RPM heads, 6-71 (I know, I know....It's what he had) with a pair of boost referenced 750cfm annular carbs, and Hardin P1000 jacketed manifolds with jacketed O/T pipes. The boat sees mostly ski and cruise duty. It has a nice manageable lope, excellent throttle response, no reversion problems, and easily pulls to 6K....Oh yeah, and no valve adjustments....

[ck7684]

I asked my local speed shop about these and he said that the cam spec numbers in the catalog were wrong. Not sure if this has been corrected or anything, but you may want to double check the numbers to be sure...

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http://www.compperformancegroupstores.com/store/merchant.mvc?Screen=PROD&Store_Code=CC&Product_Code=11-240-4&Category_Code=
this is the web address for the cam I want to purchase.....11-240-4.....there is a specs link. says it likes improved intake...and headers....but it also mentions jets................i have a 1976 468 gen 4, 1.88 and 2.15 stainless valves, 049 heads, 9:5:1 compression, torker 2 intake (should of gone air gap I know), hyperutectic pistons, 650 demon carb, with basset v drive twisty headers. Its all going into a '76 sanger bubble deck 2 seater.....I just want a nice ski/lake rod that runs on pump gas....that is for the most part dependable....with around 400 horse. Any do's or don'ts or guesses at horse power I will get from this would be great. I can get this comp cam brand new with lifters and pushrods for 188 bux shipped to my door.

[DUCKY]

Sounds like you are going to need a bigger carb.... a 650 on a big block?
Anyways, That XM278 will probably make you happy. Seems a little small for a v-drive boat, but probably fine. Comp makes good stuff and takes good care of you if you have problems. I also ran a Crane powermax H302 in a very similar application to yours and was very pleased with it. You might also want to look up Chris Straub here on the boards (cstraub69) and talk with him. I believe he is a cam grinder, and I know he's very knowledgeable.....

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well I bought the carb for 200 bucks brand new off my dad...well actually he ran it twice on his 350 chevy bike....I figured I'd have to get a bigger carb, but was told I could re jet the demon if I had too.

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at what point do you need a tunnle ram? I've herd guys tell me that single carb boats run better than duals...with less up keep. I don't know...just asking

[SBC Jetboat]

You do NOT want a tunnel ram. They're good for 6-7000 RPMs and up. NO GOOD for anything pleasure, street/strip, Edelbrock RPM Air Gap is among the best for most pleasure/race applications. I have an XM-278 in a Small Block Chevy and its a pretty decent cam. Dont have the boat in the water yet, but it sound good as S*%T. Rough idle.

[DUCKY]

I second that. You don't need a tunnel ram, in fact most of the people that have them could gain performance by losing them. On the 650 carb idea, you need to look at it like this....
if your motor is a 454, that means that it is capable of pumping 227 ci of air per revolution at 100% VE x 5500rpm = 1,248,500 ci/min /1728= 722.5 cfm x 90% VE = minimum carb size for 5500rpm is 650 cfm from a strictly math stand point. When you take air temp, density, and humidity into account, and add into your equation that carb flow ratings vary, you need at least a 750 on that motor for reasonable performance but an 850 would leave you some room to play with....