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SRH916 03-06-2008 06:16 AM

Cam question
 
In my run as an intern at a machine shop, I never thought to ask about camshafts :banghead: but I didn't buy my truck till about a week before I left. So here is my question. I have a stock 250 hp Goodwrench 350 in my truck. What would be a good cam for a "choppy" idle, nothing too extreme. Just something to get a little bit better hp and torque at higher rpm, but not so I lose alot at lower rpm.

Thanks in advance,

Jared

84lwb 03-06-2008 06:53 AM

Re: Cam question
 
look for duration over 240@50 and a small lobe center for the lopey idle.these cams will probably have high lift so you may want a custom grind if don't want a radical cam.or you can comprimise somewhere in the middle.The cam I bought for my truck is 429/429 lift 220/220 dur@50 110 lc and says it has a mild idle.

Restrorob 03-06-2008 07:14 AM

Re: Cam question
 
Here's the specs. on the one I put in my 350 with 9.5-1 pistons with extensive head work and using steel head gaskets.


Idle fair with lope, power range 2000-4800 rpm, good highway
towing with correct axle ratio, use stock auto or manual
transmission.


050 Dur. Adv. Dur. Cam Lift Valve Lift Lobe Cent
Int. Exh. Int. Exh. Int. Exh. Int. Exh. Int. Exh.
218 218 284 294 .305 .305 .458 .458 105 115

I was told if I went any larger I would need a stall converter (which I bought anyway) and would have problems with the power brakes (not enough engine vacuum).

It sounds sweeet sitting there thumping away.

streetmaster42 03-06-2008 07:41 AM

Re: Cam question
 
I've beet my brains out over this cam thing a few yrs back, with a billion calls to Summit Racing, Jegs, Lunati, Crane Cams, so on and so forth. The big point to ponder here is the fact that you have a 4000lbs if not more truck. Its not hard to turn it into a big lopey turd. They will all tell you that torque moves mass, and anything over a 218@50 is bad for a heavy truck. So i just had to get something a little better for my 9.0:1 350 sbc, (EX270 Retro-roller) 495in-502ex/218-224@50 from comp, which has a very nice rumble to a slight lope. Good luck :chevy:

benoit454 03-06-2008 09:20 AM

Re: Cam question
 
a comp cams 268 h has a lopey idle even claims right in there daily driver with a choppy idle and it's true I run one in my monte carlo.


I want the same cam for our 84 a lopey cam but not lose low end.

I would have to agree with them stay under or around 218 duration, and I heard if you get the tighter lobe seperation it'll make it good and luimpy or lopey on idle.

Also as for comp you can run a stock convertor with the magnum 280 they say it right in the summit book and northern auto. Says largest cam for stock convertor use with aftermarket manifold 4 bll and likes headers.

Russell 03-06-2008 10:56 AM

Re: Cam question
 
I have a comp cams 262H in my truck. When I can get it to run, it has a slight lope. However, that may just be the dead cylinders due to a couple wiped lobes, doah!

ton*loc 03-06-2008 06:24 PM

Re: Cam question
 
if you want bad ass sound with good power range check these out
http://www.compcams.com/Thumpr/default.asp comp cams new thumper series :metal:

Dooley 03-07-2008 10:55 AM

Re: Cam question
 
The hydraulic cam I have in my plow truck has served me well.

intake and exhaust are .4425
intake and exhaust duration is 288@50
Overlap 64
Lobe centers 107
intake opens BTDC 0
intake closes at ABDC 34
exhaust opens BBDC 44
exhaust closes ATDC 10

Wolverine brand. I don't think they grind'em like that much anymore!
Stump pulling power.
Running 9.5 flat top pistons, bored 30 over, stock heads with 3 angle cut.
Rocker arm ratio 1.5:1

Nice lope, especially when cold!

caminokid 03-07-2008 10:57 PM

Re: Cam question
 
Quote:

Originally Posted by ton*loc (Post 2612268)
if you want bad ass sound with good power range check these out
http://www.compcams.com/Thumpr/default.asp comp cams new thumper series :metal:

Thats the sound I am looking for in all my trucks.

ton*loc 03-08-2008 06:20 AM

Re: Cam question
 
here is a video of a big block on the dyno with that cam


sounds cool

Billla 03-08-2008 07:14 AM

Re: Cam question
 
http://67-72chevytrucks.com/vboard/s...71&postcount=2


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