camel back heads?

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HotRodPC

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265HP its the factory rating I do believe.

Anybody heard from driver4r today?

Why Yes, Yes I did. I think he did make 1 post today. Unless I seen an old post of his. :shrug:
 

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The question I always wanted to know, was how to get the lopey idle, and still maintain low end grunt/drivability.. :D

What's the deal with the "thumper" cams that claim they do this?

I actually thought about having a valve on the vacuum brake booster that one could open at will to make their engine "sound mean" LOL..
 

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The question I always wanted to know, was how to get the lopey idle, and still maintain low end grunt/drivability.. :D

What's the deal with the "thumper" cams that claim they do this?

I actually thought about having a valve on the vacuum brake booster that one could open at will to make their engine "sound mean" LOL..

The thumpr cams are just high durration cams. this is for high rpm horsepower and when it sounds "mean" it is missing at idle because of the high durration. For the low end grunt you want a smaller durration so you will probably need to settle for something in between.
 

HotRodPC

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The thumpr cams are just high durration cams. this is for high rpm horsepower and when it sounds "mean" it is missing at idle because of the high durration. For the low end grunt you want a smaller durration so you will probably need to settle for something in between.

and to further the explanation, the "miss" is caused from a compression leak. Valve Overlap is what causes the lope sound. That's where you're valves are open so long, that one is already opening before the other one is closed. This is why if you have 11:1 pistons, and a big cam, by the time you leak off compression in valve overlap, you might actually be at 9:1 compression and pump gas is fine for 9:1 compression. Kinda sorta anyway. It get's more technical than that, but yes, it's hard to have bottom end grunt and be loping cuz if you loping at idle, that means you're motor IS NOT efficient at the low rpm where you're wanting it to perform best.
 

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I understand the duration stuff, and how you can putz with higher cranking compression to counter it, etc.. I just saw the ad on the thumper cams where they said they had the distinctive lopey idle of hight duration idle without sacrificing drivablilty. I was trying to figure out how this could be done. I've seen chip programs that you can set up a lopey idle for EFI, and as soon as you are in gear it smooths it out. I've even when I was younger very much considered like I said, a valve I could remotely open on the vacuum booster to get that vacuum leak to lope it a bit. I was just curious if there was something where they set up the duration to be separated further in, say 800-1000 rpm that closed up as you approached, say 2,000 rpm giving you a pretty good cruising efficiency, while having that lope when you are just idling.
 

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I mean, I know duration is duration, that came out wrong, I am thinking about the power band, that you could set up a power band on your cam (maybe with the roller cams and stuff where we are seeing much more abrupt slopes?) that comes on early that has lots of duration, that would idle rough?

Maybe increase valve train wear would be my concern..
 

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Suppose I could just turn the idle speed way down to where it's barely running..
 

HotRodPC

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Suppose I could just turn the idle speed way down to where it's barely running..

That's what alot of guys do when they want to sound like they have a big cam.


Some other real stupid ways to do it, is with a manual choke, have the choke on about 1/3 the way causing a very rich condition, it will sound lopey, you can also lean out the carb to far and cause a lean misfire at idle. Neither are good though.
 

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Some other real stupid ways to do it, is with a manual choke, have the choke on about 1/3 the way causing a very rich condition, it will sound lopey, you can also lean out the carb to far and cause a lean misfire at idle. Neither are good though.

Sign me up for fuel washed cylinder bores just so I can sound cool!
 

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Sign me up for fuel washed cylinder bores just so I can sound cool!

It the slug truck that sounds fast... We had a kid worth a stock LG4 Camaro that used to cruise with us. Car had a 6" pin on cowl hood on it. That kid would fall into the same category... The hood was faster than the car.
 

HotRodPC

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I never could understand why guys wanted to "SOUND" fast, especially when they weren't. For me, I liked my **** to be all ugly, very little chrome, look OEM as could be sound stock as could be, then negotiate a race with some guy that's loping off the motor mounts and to get all the space they'd give me, then beat them by fender or a car length and take their money. Then I'd race their buddy who was just a little faster than them with the same race and beat him by a fender or car length and take his money too. Truth be known, I pretty much knew the whole time I'd beat them heads up cuz it takes more than a a big cam and chrome to go fast.
Can't say I won them all, but I did win the majority, and I don't recall a night ever went home losing cash. If I lost one, I'd make it up on the next one. You can't win them all anyway. You'd never be able to get a race if you spanked everyone.
 

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Best sound that can EVER come from your truck, is your ole lady hollering from you bangin the **** outta here across the bench seat.
 

HotRodPC

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Best sound that can EVER come from your truck, is your ole lady hollering from you bangin the **** outta here across the bench seat.

Yepper, Been there done that !!! Other thing nice about smaller women. I been going to highway at 70 getting the groove on. That's pretty fun too. :waytogo: If my trucks could talk, including my work trucks, :laughing1: OMG !!!
 

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If my trucks could talk they'd have to open a battered trucks shelter. :lol:
 

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