340 Stock Camshaft

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dodge freak

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Been looking at these new cams. Seems like so many are grounded on a 108-112 LSA. What I understand is a 114 LSA gives a smoother idle but if the .050 is around 224-230 it still pull good past 6000 rpms.

Seems like everybody wants that lumpy idle sound, even if the cam is too big for their set up.

The only cams I see today that have a 114 LSA is the old 340 cam. I do know the 1968 340 manual trans motors had a bigger cam-still grounded on a 114 LSA but is no longer made.

The Voodoo cams have 112 LSA on the smaller grinds but then go to 110 LSA like everybody else as they get bigger.

Anybody make a big cam-like the old GM 327 cam, thats a 224 @ .050 but has 114 LSA for a great idle and still will rev to 6500. What about a mechanical cam thats ground on 112 LSA thats not for a racing motor. DDC had one for the 273's but again its no longer made.
 
Most cam companies can grind any of there cams on a wide lsa for you.
 
The narrower they get, the more top end pop they should have. Idle quality is important for a new car being sold to John Q public, but not so important to the hot rodder or racer.
 
I just installed a cam with 114 LSA in my 273 but it is 218 @ .050 intake and 228 exhaust. It has a .441/.441 lift.

Summit part # sum-6901
 
Which I understand is good for a lower compression motor but the idle will be very rough and low vacuum
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No, I don't think so. This cam has alot of overlap which bleeds the compresion off and the lower numeric centerline also lends to this problem. At higher RPM's, this problem goes away because the engines efficeintce (SP!) goes up and a ramming effect takes place.

The wider 114 helps retain compresion at low RPM.

I have (For sale as well) the MoPar 288/ .499 oval track Hyd. cam. No tappets. It is a 108 to be installed at 106.
 
Heres the thread...http://www.forabodiesonly.com/mopar/showthread.php?t=27295
 
What I like is something that idles good-does not have to be like a new car but then it needs not to sound "bad ***" Have OK mileage-since gas cost so much now and will work with my 3.91 gears.

Yes, those gears are eating my gas but I like the power. Its a 318 rebuilt and has 360 308 heads the high swirl type. I have a eddy rpm intake on it now. As for a carb I am thinking a holley 650 or a Carter 600-625 might help too.

The heads have been milled .030 and has 63cc chambers, I check them myself-thanks Wal Green for the 5cc shooter, cranking compression is 160 psi.

Is the Summit cam a good pick, seems hotter than the stock atuo trans cam. The Vodoos I am not sure how it idle, maybe the 400-401 but those seem small too.
 
dodge freak said:
What I like is something that idles good-does not have to be like a new car but then it needs not to sound "bad ***" Have OK mileage-since gas cost so much now and will work with my 3.91 gears.

Yes, those gears are eating my gas but I like the power. Its a 318 rebuilt and has 360 308 heads the high swirl type. I have a eddy rpm intake on it now. As for a carb I am thinking a holley 650 or a Carter 600-625 might help too.

The heads have been milled .030 and has 63cc chambers, I check them myself-thanks Wal Green for the 5cc shooter, cranking compression is 160 psi.

Is the Summit cam a good pick, seems hotter than the stock atuo trans cam. The Vodoos I am not sure how it idle, maybe the 400-401 but those seem small too.
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I had bad heads on my 273 and just got some rebuilt 302 swirl port heads installed. Now I have 8.85 compression and have not checked the cranking compression yet. The cam has a slight lope to it and I have now regained my torque back and horses. I had a Mopar .474/.474 lift cam in it but it was no good in the lower RPM range. Sounded good however. I was recommended the Summit cam by Bobby at BJR Racing and it was a good choice for my smaller motor. Today I took off my 500 CFM Edelbrock carb and put on my friends 750 Edelbrock carb and could not really tell bunch of difference but it seems that the 750 "is there" quicker than the 500 CFM in which in my eyes is a two barrel carb. With the 750 there is no over rich smell as you might think and does not over load the motor. I will do some testing again tomorrow. I really don't see why you wouldn't go wrong with a 750 CFM with the gears you are running, larger motor.
 
I have two Holley 750's right now. A down leg booster and one annual type booster 9379-that seems to help low speed power-which already was great.

My mileage was 10 mpg with the 318 heads, then with the 360 heads and a single plane Holley street Dominator intake, it went to 9 mpg. Now with the RPM intake its back to 10 mpg, maybe 10.5 and has more power than ever.

My cam is 30,000 miles, 6 years old, so I guess my chain is loose-timing does move at high rpms, 4000- no race motor. The cam must have seen its better days too, so I might be doing a in the car cam swap soon. Done it before, same car. Cam slips just out without removing the grill-no A/C.

It has adjustable rockers so I am open to either a H or M

I just need to decide what to get :geek:
 
dodge freak said:
I have two Holley 750's right now. A down leg booster and one annual type booster 9379-that seems to help low speed power-which already was great.

My mileage was 10 mpg with the 318 heads, then with the 360 heads and a single plane Holley street Dominator intake, it went to 9 mpg. Now with the RPM intake its back to 10 mpg, maybe 10.5 and has more power than ever.

My cam is 30,000 miles, 6 years old, so I guess my chain is loose-timing does move at high rpms, 4000- no race motor. The cam must have seen its better days too, so I might be doing a in the car cam swap soon. Done it before, same car. Cam slips just out without removing the grill-no A/C.

I just need to decide what to get :geek:
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So basically are you trying to improve gas mileage?

If so I guess the smaller 650 class carbs would do you justice and the cam that I installed might not be to bad a deal either. From your top post you almost described my cam that I just installed so that's what got my attention. Bobby and I did some research on his computer and found that .446/.446 lift cam was the stock 340 cam. So the cam I installed is close to that BUT I don't know the true LSA on the 340 cam. The cam that you found on ebay is nothing but a brute for a smaller motor. I found that .474 lift is to much on my motor. The main thing is to have every part work with each other cam, carb, intake, heads, need to be in the same RPM range. That is what I did with my motor recently. It runs better than it ever has.
 
It's easy to over cam and over carb any small block engine, so being conservitive is best.
 
Yeah, I want my cake and eat it too, ha ha.

Right now power is #1 gas mileage is 2nd but IF we get that $4 a gallon gas this summer it be a tie.

I do have a set of 3.21 gears in my basement-which I hope can stay there but I am sure it get me 2-3 more MPG-with a change in my ET- not the right way :sad11:

Boy my top speed would be way up there but I am already way out right now. I live in Michigan, not out west
 
dodge freak said:
Yeah, I want my cake and eat it too, ha ha.

Right now power is #1 gas mileage is 2nd but IF we get that $4 a gallon gas this summer it be a tie.

I do have a set of 3.21 gears in my basement-which I hope can stay there but I am sure it get me 2-3 more MPG-with a change in my ET- not the right way :sad11:

Boy my top speed would be way up there but I am already way out right now. I live in Michigan, not out west
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I'm sure you have something else that you drive I hope so I would just build for the most power possible. Leave the gears there. "MPG and change in my ET" should never be said in the same sentence. LOL!
 
LOL agreed. Supercharge it and you'll get both done.
 
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