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Cam selection for a 383 stroker

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Old Jul 23, 2005 | 09:40 AM
  #1  
wwarnke's Avatar
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Cam selection for a 383 stroker

I am building a stroker for my 1978 C-10 (single cab, long bed).

I am at the point where i need to decide on a head/cam setup.

The truck is not a daily driver, it is a weekend toy, with occasional tow/hauling.

I have a built 700R4 and 3.73 posi 12 bolt with 29 inch tires.

I am looking for something with 9.5:1 CR, enough vaccuum to have power brakes, run my A/C, and not have a Rough idle.

A nice lopey idle is ok, I would like to tow every now and then, yet when I stand on it, I want it to run like a raped ape.

I do not hear much about Performer RPM cams and heads, are they not that good, or is there better stuff for the same money.

I want to stay with a Hydraulic flat tappet cam (for cash flow reasons)

What about DArt heads, or, sportsman II

Any insight will be greatly appreciated.
Old Jul 24, 2005 | 11:58 AM
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Re: Cam selection for a 383 stroker

What about a set of modified Vortecs and a CC 270 Magnum (or the XE268)? You'd need a Vortec specific intake manifold. Vortecs would give you the TQ you need.

Edelbrock redesigned their heads so the RPM heads would be a good choice also. I'd stay away from the Edelbrock cams though. Call Lunati and ask them about the new "Voodoo" cams. It's Lunati's somewhat new line of cams to combat the XE series from Comp. Cams. Good luck.
Old Jul 24, 2005 | 02:09 PM
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Re: Cam selection for a 383 stroker

Originally Posted by 406TA
What about a set of modified Vortecs and a CC 270 Magnum (or the XE268)? You'd need a Vortec specific intake manifold. Vortecs would give you the TQ you need.

Edelbrock redesigned their heads so the RPM heads would be a good choice also. I'd stay away from the Edelbrock cams though. Call Lunati and ask them about the new "Voodoo" cams. It's Lunati's somewhat new line of cams to combat the XE series from Comp. Cams. Good luck.

I would advise AGAINST the 270 as it's a single pattern cam for use with the vortec heads. Look at what GMPP did on their 350HO that came vortec-headed... they had 10 degrees more exhaust duration than they did intake.

The 268xe made virtually the same power as the 212/222 they used from the factory in a dyno test. So, I would try and get a grind with more emphasis on a better sized duration split.

Remember, this is a stroker motor, not 350ci. I think he could go for a little better cam then just a 270 anyway.

What do plan to tow exactly? That could change things.
Old Jul 24, 2005 | 02:40 PM
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Re: Cam selection for a 383 stroker

Vortecs would probably be a good choice for an inexpensive cast iron head. I've also used Dart Iron Eagles (200cc intake ports- a 383 will swallow them with no problem) many times with good results, although they are getting pricey. World Products Sportsman IIs would also work well, although I've only used them once myself. Aluminum heads are pretty pricey for what you're after, plus I like cast iron heads for heavy duty use- like towing and such where you're into the throttle pretty deep for long periods of time.

If you want a CHEAP cam that works, try one of the Summit house brand cams. $79 complete with lifters! They are NOT very aggressive cams but that makes them perfect candidates for use with 1.6 rockers. End result will be valve action that's about as aggressive as a Comp Xtreme Energy or Lunati Voodoo cam with 1.5 rockers. Check out the Summit K1103. It's a 214* I/224* E duration on a medium-wide 112* LSA which will give you a good idle and plenty of vacuum. Midrange punch should be excellent. Next smaller cam would be the K1102 which has 10* less duration across the board.
Old Jul 24, 2005 | 09:48 PM
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Re: Cam selection for a 383 stroker

Thanks everyone, I was thinking of the the Vortec heads, but was concerned about being limited to .475 lift. I dont tow very often, when i do, it a jet ski, a low boy trailer or something like that, nothing huge like a motor home. I have seen the Dart heads, new, on Ebay for around 600 bucks.

I want a good sized cam, when it idles, i want to know there something under the hood.

So, RPM heads good, and RPM cam bad? The RPM cam seem to have a very wide power band, from like 1500 to 6500 rpm, which is right where i want to drive. With the 373s and the .7 OD, 70 mph is around 2200 rpm, but when I'm at WOT, the 700R4 wont shift till 5k to 5100 rpm, Currently, I can not get it to shift to OD while at WOT. I dont have enough motor or cam to get me high enough RPM, My small cam (Crane 260H) pretty much fall on its A$$ about 4600 rpm.
Old Jul 25, 2005 | 09:34 AM
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Re: Cam selection for a 383 stroker

Here's a Desktop Dyno 2003 screen of the 383 I have on buildup. The cam is definitely too aggressive for what you're looking for, but a slightly lower duration/lift might do you good.

http://www.bandhproductions.com/memb...383stroker.jpg
Old Jul 25, 2005 | 05:15 PM
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Re: Cam selection for a 383 stroker

I have also been trying to find a set of pistons. I am looking a Hypereutectics, but wonder if cast pistons would do the job? Since, of course, everything is on a budget.

What are the limits of a set of cast piston, maybe like a set of Flat top Badgers or something. Compared to a set of Speed Pro Hypereutectics?

All I want is 400hp/425tq and be able to drive it as often as I can afford to feed it.
Old Aug 1, 2005 | 11:26 AM
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Re: Cam selection for a 383 stroker

Cast pistons will do just fine. It's detonation that kills cast or hypereutectic pistons. You won't be leaning on them hard enough or spinning high enough to fid their limits otherwise.
Old Aug 5, 2005 | 09:10 PM
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Re: Cam selection for a 383 stroker

Well, I found a set of pistons. KB Hypereutectic Flat tops. They even came with PM rods, Moly Rings, and have been clerance for a .600" lift cam. All for the bargain price of $170.

Dude said that he had a motor built by his local machine shop, then, during the initial run on the dyno, found that block cracked one of the water jackets. The shop would not make good on the deal, therefore, he is trying to recoupe some of the cash from the build.

I could not find the part number on the internet, but he said that they were supposed to be 9.8:1 with 64cc heads.

When the catalog says say, 9.8:1 with 64cc chambers, what about deck height, and gasket thickness? Are they assuming a standard measurment for the two, like a .041" gasket, and whatever deck?

Can someone help me figure out exactly what pistons they are? Number on inside of piston reads 1387P, and have the numbers .030
stamped on the top of all of them.
Old Aug 5, 2005 | 09:59 PM
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Re: Cam selection for a 383 stroker

KB uses a 3 digit numbering system. e.g. KB127. TRW uses a 4 digit numbering system, but uses an "F" to denote forged, their hypereutectic pistons use 3 digits and a "P". 030 means it's 30 thou oversize. You can go to flatlander racing site and they list a bunch of pistons there.
Old Aug 12, 2005 | 10:04 AM
  #11  
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Re: Cam selection for a 383 stroker

You're right about the compression numbers- they are really estimates because they may or may not take into account the deck height of the piston, the TRUE head gasket volume (which is always more than the mathematical calculation based on your bore size and gasket thickness) and, of course, the chambers could be a few cc bigger or smaller than spec.
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