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First off, I have a 1959 Chevy 283 that was rebuilt stock last year. It was a 2 barrel engine. After the rebuild i put a weiand street warrior intake with a edelbrock 600 4 barrel, 262 Comp extreme energy cam. The problem is that it runs fine, starting, idling, but when you put in gear it drains the motor down. And its weak. Do i need a stall? Or timing issues, carb adjustments? Or is it the stock heads? ANY HELP?::confused:
 

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Did you change the valve springs, did you lap the valves, did you check pushrod length?
Do you know what your compression ratio was in the 2-bbl configuration; and is the cam suitable for the compression ratio? Do you have enough rear axle ratio to support the camshaft?
 

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. That 218/224 cam likes about 10.0-11.0:1 compression ratio and wants to make about 400-425HP...

. You're 283 is prolly about 8:1 if stock rebuild and the stock heads prolly die by about 290HP...

. The engine is going to run like it has a vacuum leak up to about 2,000 RPMs... and then never be real strong... a bit of a mismatch of parts... you could go domed pistons and better heads if this is a racer...

. Or for street use as is something more like a 194/202 cam...
 

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If you have a bigger cam and rebuilder pistons and lower compression ratio,you will have tuning issues and not as much power as you should have. That little cam has correct specs for your application,BUT!!! if your CR is compromised then the parts will not work well in this engine.
Its not even easy to do a head swap to increase cr.You might have to take the engine apart and deck the block and shave the heads?You are using 283 heads?
 

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First off, I have a 1959 Chevy 283 that was rebuilt stock last year. It was a 2 barrel engine. After the rebuild i put a weiand street warrior intake with a edelbrock 600 4 barrel, 262 Comp extreme energy cam. The problem is that it runs fine, starting, idling, but when you put in gear it drains the motor down. And its weak. Do i need a stall? Or timing issues, carb adjustments? Or is it the stock heads? ANY HELP?::confused:
The main problem here is that you don't understand matching the cam timing to the static compression ratio of the motor. A camshaft is not a stand-alone part. It is dependent on other facets of the build to get to a well-coordinated platform. I would be very surprised if that motor is even 8.5:1 static compression ratio and common sense would tell me that it's even less than that. Take a look at this chart I put together. Everything on this page was taken directly from the Crane Cams catalog, as far as matching static compression ratio to the 0.050" tappet lift duration.
http://www.crankshaftcoalition.com/wiki/Cam_and_compression_ratio_compatibility
I have an idea that if you had chosen a cam something like this.....
Crane Cams 114112 2020 Hydraulic Flat Tappet Camshaft Lifter Kit Chevy 262-400 V8 57-87 RPM Range: 800-4400, Duration @.050": 194/204, Lift: 0.401/
that you wouldn't be writing the post here in the first place.

Thanks AutoGear and BuzzLOL, you guys nailed the problem before I chimed in.
 

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Discussion Starter #7
Im not sure on most of these questions. I have very little knowledge on engines. Someone rebuilt as stock with a 2 barrel. While still fresh, i had someone install cam and intake. Its just flat running. And as before it loses alot of power when put in gear. Torque converter issue? And the heads are stock. Im not sure which way to turn. Could be simple or expensive....
 

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Im not sure on most of these questions. I have very little knowledge on engines. Someone rebuilt as stock with a 2 barrel. While still fresh, i had someone install cam and intake. Its just flat running. And as before it loses alot of power when put in gear. Torque converter issue? And the heads are stock. Im not sure which way to turn. Could be simple or expensive....
Remove hot rod cam. Install stock cam. Done.
 

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I agree with some of the info here. Definitely check for vacuum leaks, get the timing right, valve adjustment, etc.
But a 262, [email protected] .050" needs 10-11:1? Really? Even if it's 8.5 I would think it should run ok. Do you think a 262 is THAT big of a cam, even in a 283? Maybe 10:1 would be ideal, tho. (would that mean a 280 Magnum cam needs 12-13:1 then?) Or are you saying smaller motors need to have higher CR than larger motors with the same cam?

IS IT OFF A TOOTH?

You did state that when put in gear, it "drains the motor down". Maybe it does have a vacuum leak or a carb problem...or a way tight converter.

If you're not going to change heads yet, maybe try advancing the cam another 2 deg (over the 4 deg Comp already has in it). I agree, definitely get a higher stall converter no matter what. I would do that before gears.
Would like to see how it makes out!
 

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I agree with some of the info here. Definitely check for vacuum leaks, get the timing right, valve adjustment, etc.
But a 262, [email protected] .050" needs 10-11:1? Really? Even if it's 8.5 I would think it should run ok. Do you think a 262 is THAT big of a cam, even in a 283? Maybe 10:1 would be ideal, tho. (would that mean a 280 Magnum cam needs 12-13:1 then?) Or are you saying smaller motors need to have higher CR than larger motors with the same cam?
Maybe this will help......
http://www.crankshaftcoalition.com/wiki/Cam_and_compression_ratio_compatibility
This information was gleaned from the Crane Cams Master Catalog and re-composed to suit easy reading while showing all the relative information from the catalog.
 

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I'll check er out, thanks. Just seems to be a fair amount of contradiction on builds sometimes. A 274xe is fine with 9:1 (((didn't say ideal))) but hearing a 262xe needs 10+ just makes me wonder. I do know that a smaller motor needs more static CR to keep up the dynamic CR vs a larger motor with the same cam.....just don't see it being a huge difference.
Thanks.
 

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I'll check er out, thanks. Just seems to be a fair amount of contradiction on builds sometimes. A 274xe is fine with 9:1 (((didn't say ideal))) but hearing a 262xe needs 10+ just makes me wonder. I do know that a smaller motor needs more static CR to keep up the dynamic CR vs a larger motor with the same cam.....just don't see it being a huge difference.
Thanks.
If you were building a motor, would you want it to be correct or would almost correct be good enough?
 

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Even if it's 8.5 I would think it should run ok.
. Yes, any motor with any cam will start and run... old OilPull engines with 3:1 compression ratio will chug along at 160 RPMs flat out... will it perform very well power curve wise and MPGwise in the modern sense? No, to one extent or the other...

. Hublee, where are you located, might put that in your profile... prolly members here near you...

. Sorry if we got carried away in a discussion here that maybe you didn't understand... to put it simply, you have a good engine... you have a good cam... but they don't work well together... as you've discovered...

. If you want to put a minimal amount more money in it to fix it, you need a smaller cam... sell the other one... it will prolly cover the cost of the smaller one... like a Summit K1101... (you'll be out labor costs if not doing it yourself)... your engine came stock with something like a K1100...

. If you want to keep the current cam, which at
 

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If you want to keep the current cam...
(time to edit ran out)

. If you want to keep the current cam, and are able and willing to put more money into the engine, then you will need to change the engine to be like an old stock 250HP or 283HP 283", your 218/224 hydraulic cam is kinda close to the 228/230 solid lifter cam those engines used once the lash is taken out of the spec.s... those engines used "9.75:1" compression ratio (I think they called it '10:1') and for your engine (8:1) to run well and properly it would need to be modified to be close to the same... like 9.75 - 10.5:1... this would mean flat top or mini-domed pistons as a minimum... most anything else we mentioned above really isn't needed... it would help, but not required to be a strong 'driver'...
 

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If you were building a motor, would you want it to be correct or would almost correct be good enough?
Could see if he was talking a 280 Magnum or something with that compression/heads. But probably is best to be on the high side of compression the smaller the motor. And you are correct, optimal is best.
 

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. Yes, any motor with any cam will start and run... old OilPull engines with 3:1 compression ratio will chug along at 160 RPMs flat out... will it perform very well power curve wise and MPGwise in the modern sense? No, to one extent or the other...

. Hublee, where are you located, might put that in your profile... prolly members here near you...

. Sorry if we got carried away in a discussion here that maybe you didn't understand... to put it simply, you have a good engine... you have a good cam... but they don't work well together... as you've discovered...

. If you want to put a minimal amount more money in it to fix it, you need a smaller cam... sell the other one... it will prolly cover the cost of the smaller one... like a Summit K1101... (you'll be out labor costs if not doing it yourself)... your engine came stock with something like a K1100...

. If you want to keep the current cam, which at
I posted a little while ago about advertised duration vs compression. That Summit cam has 270 vs 262 for the Comp. So the later intake closing point of the Summit cam will build more cylinder pressure than the shorter Comp? I'm really asking, by the way, not being a schmarty. I've always thought that 2 cams with the same duration @ .050, the one with less advertised doesn't need as much compression because the intake valve closes earlier.
 

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. Manufacturers never standardized on advertised durations, what lift to use to calculate them, so it's hard to know if numbers from one brand to another actually compare... even in the same brand, numbers may vary, in the 1960's everyone wanted long duration that was gentle on the valvetrain and would last forever, so manufacturers put out big advertised duration numbers... in the 1980's, everyone wanted short durations for better MPG, so manufacturers magically came up with shorter durations on the same lobes by measuring them differently... that's why we look first at the durations at standardized .050" lift...
 

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OK I agree, especially if it is as low as 8:1 or worse. And I did read your comment on the ideal build, and agree.
 

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you should calculate your CR with 49CC heads.If its good you can buy excellent heads with those chambers.your engine should be .060 over
 
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