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Discussion Starter · #1 ·
i am looking for a cam for vortec 350... i am going to use a flat tappet cam looking for somethen to make alot of noise... wnat a good rough idle.. i know it wont run great thinking like this but ...i have my reasons... what makes a cam idle rough..the duration or lift..
 

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More machine than man
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A rough idle is determined by:
1) intake valve closing (the later it closes, the rougher)
2) Valve overlap (more overlap the rougher)
3) LSA (smaller number the rougher)

All these factors cause reversion, that is intake charge is reversed and pushed back up through the carb. Comp Cams makes a line of cams called "Thumpr" that is intended just to rattle and make noise. Performance wise they are not that great. They are just designed to thump.

COMP Cams: Thumpr™
 

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Discussion Starter · #4 ·
Should have added I am using vortex heads so I can't go over 480 in lift and I am on a budget..... this is a request from customer ....so cheap is what he wants but wants to sound like a street machine.... its a big argument ...but that's what he wants ...is there any cheaper can to use to get this
 

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More machine than man
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Well you are getting a new cam and new lifters, so having the valve guides ground down isn't going to add that much to the cost. You can even get a tool from Comp Cams or Crane Cams to perform the work yourself if you don't want to send them off to a head shop. Also the 279TH7 Thumpr cam has 0.479/0.465" lift so that meets your reqs.
 

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What does he have for an exhaust? What headers, pipe, mufflers?

If he has a good exhaust i'd run the 1785p cam from elgin. It needs a good exhaust setup though. There are videos of it on you tube to give you an idea of sound.

For mufflers id use thrush welded mufflers. Great sound and very reasonable price.
 

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Discussion Starter · #8 ·
Set of Hooker headers.. 2.5 dual to a set of raptor mufflers in a H pipe setup.... I can't first d any videos of the cam.... the Guy wants 2.02 heads cantly bad...but I can't afford them I have a good set of vortecs in the shop....
 

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Discussion Starter · #10 ·
This is a build for a trade....no money ..... this build is out of my pocket.... so trying to keep it cheap cheap but decent power he is looking for 300hp out of the 350..... I figured the vortecs the can mentioned above and a airgap I take should make 350-400 hp or so
 

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you mention that this is a vortec 350 which automatically makes me think that this is a 96'-00' vortec 350 motor. if so these were factory roller lifter cam motors and the lifter bores are larger in diameter than the older flat tappet style motors. running a flat tappet lifter in these motors is not going to work, that lifter will slap all around and the cam nor lifters will last longer than the time it takes to break the cam in.
 

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Howards CL112431-06 cam/lifter kit would be an equivalent cam to the Isky 201268 recommended by F-Bird'88 with .450" lift, 223* @ .050" vs 224* @ .050" for the Isky cam. The Howards cam/lifter kit is $139.95 at Summit Racing, compared to $169.95 for the Isky cam with no lifters. Howards and Isky are the only 2 companies that grind all their cams in-house. There are Howards grinds that are equivalent to the other 2 Isky cams F-Bird'88 recommended, they don't come in cam/lifter kits, but they would save some money over the equivalent Isky grinds.

Ed
 

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X2,

and I'm willing to bet if you called Howards Cams that they would be willing to work a deal on selling you those other two cam profiles as a cam/lifter set for roughly the same price as their other kits.

Howards valvetrain products is all I ever use anymore, I've found them to be of great quality, price, and they also have great customer service. For as much as I recomend HRC products, I think I should get a discount on my next HRC purchase. :D
 

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I am a big fan of Isky Cams, but if you want to save some money you can go with one of the Crane cams sold under the Summit brand name. A cam/lifter kit will run around $120-$140 complete.
If you want lots of rumble and all sound you need a small (close) LSA number like 106-108 max. Long duration will help too, but I wouldn't go too long and have all low end power suffer.
SUM K00172 will give you a rough idle and not sufer ffrom low end power loss, it will also work with a stock converter, if the car is an automatic. 274/274 .450 lift and 106 LSA. $139. for cam and lifters.

edit-Oops! That Howard's cam is pretty much identical to the Crane/Summit cam set.
 

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you mention that this is a vortec 350 which automatically makes me think that this is a 96'-00' vortec 350 motor. if so these were factory roller lifter cam motors and the lifter bores are larger in diameter than the older flat tappet style motors. running a flat tappet lifter in these motors is not going to work, that lifter will slap all around and the cam nor lifters will last longer than the time it takes to break the cam in.
Really?? I and a couple people have ran flat tappets in these blocks and zero problems. Mine actually went in tighter than they should have and needed the lifter bores honed.
 
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