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found a cam.. what do you think???

RootBreaker

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help me choose please...

ok so I found a cam.. new pulled from a motor...
I was looking at a comp cams 4x4 xtreme... $250 for hydraulic roller....
http://store.summitracing.com/defau...ail.asp&part=CCA-08-411-8&N=120+400114+302618

Intake Duration 050 inch Lift: 210
Exhaust Duration 050 inch Lift: 214
Duration at 050 inch Lift: 210 int./214 exh.
Advertised Intake Duration: 260
Advertised Exhaust Duration: 264
Advertised Duration: 260 int./264 exh.
Intake Valve Lift with Factory Rocker Arm Ratio: 0.474
Exhaust Valve Lift with Factory Rocker Arm Ratio: 0.474
Valve Lift with Factory Rocker Arm Ratio: 0.474 int./0.474 exh. lift
Lobe Separation (degrees): 111

however I found this...
Duration @ 0.050" Lift: 208/221 Lift: .474"/.510" Lobe Separation: 112 Type: Hydraulic roller tappet 5.7L HO 350 This came out of a brand new 350 HP crate engine ZZ4
for $150.... I dont know anything about cams.. does this seem good or just as good? work well in our trucks???
Thanks
Jeff
 
Was this covered/said before?

Aftermarket roller cams are junk IMO. You are better off starting with a factory roller block and using stock roller components than you are running aftermarket roller stuff. (Unless you have absolutely no choice)

This coming from someone that is running aftermarket roller cam stuff in a non-roller block. I should have started with a newer block.

I'd go with a $150 (guessing on price) flat tappet cam way before I went with a $500 aftermarket roller cam/lifter set unless I needed every last 10th of a second. You could probably get your hands on a roller block (one piece rear main too!) plus the flexplate for less than that $500.

If you've got good flowing exhaust (especially the ports) then perhaps a single pattern (same intake/exhaust lift) cam is ok, but most often, a modern (dual pattern) cam seems to be the best bet, as it helps hide the typically poor exhaust side of stock GM heads.
 
dyeager535 said:
Was this covered/said before?

Aftermarket roller cams are junk IMO. You are better off starting with a factory roller block and using stock roller components than you are running aftermarket roller stuff. (Unless you have absolutely no choice)

This coming from someone that is running aftermarket roller cam stuff in a non-roller block. I should have started with a newer block.

I'd go with a $150 (guessing on price) flat tappet cam way before I went with a $500 aftermarket roller cam/lifter set unless I needed every last 10th of a second. You could probably get your hands on a roller block (one piece rear main too!) plus the flexplate for less than that $500.

If you've got good flowing exhaust (especially the ports) then perhaps a single pattern (same intake/exhaust lift) cam is ok, but most often, a modern (dual pattern) cam seems to be the best bet, as it helps hide the typically poor exhaust side of stock GM heads.

thanks for the input... the part that was mentioned before was that I was going to get the xtreme 4x4 cam from comp cams... but I also found another cam but dont know if the specs for it are for a car and not a torquey truck....

I have a
L05 vortec block (1991)
1 piece rear main
hydraulic roller cam already
cast heads
used to have tbi but i put a z-28 intake on and holley truck avenger...
Other than my clutch slipping... I want to wake the motor up...
a friend of mine already told me a simple intake upgrade will help...
 
I remember something about this. I still like the comp cam better but the cam out of the ZZ4 will be very close to the same performance. Head work later and a taller ratio rocker arm will wake either came up. I wouldn't mind seeing a tighter lobe seperation angle on either cam but I still think you will like the performance. Just out of curiosity, what is the powerband for a ZZ4 motor?
 
resurrected_jimmy said:
I remember something about this. I still like the comp cam better but the cam out of the ZZ4 will be very close to the same performance. Head work later and a taller ratio rocker arm will wake either came up. I wouldn't mind seeing a tighter lobe seperation angle on either cam but I still think you will like the performance. Just out of curiosity, what is the powerband for a ZZ4 motor?

That is my point.. seems both cams are close... however the zz4 one is on ebay... (dont mind telling you all because they have more and im not ready yet)

xtreme cam is $250 for hydraulic roller cam only
zz4 cam is a NEW pull from a zz4 hydraulic roller cam only and is $150.....

save $100 but is the zz4 cam a higher rpm cam not as long of a torque curve.. I appologize for being non savy on cams.... I just want more bang for my buck and expect to do intake when I do the cam.. and maybe heads later.....
Thanks
Jeff
 
LT4 Camshafts are about $199 from Scoggin Dickey. They are brand new GM made roller camshafts. 203/210 @ .050. I have one for my 383. No experience with it yet, the $50 cheaper and computer friendly factors were my big selling points.
 
Well, '91 wn't be a Vortec block, Vortec V8's were 1996+, that's it. 4.3's I've seen with "Vortec" on the valve covers MUCH earlier than that date, but not V8's. In any case, a Vortec block or not really means nothing. It's a one piece rear main roller cam 350. I'm envious. :)

A lot of "larger" cams (like that ZZ4) are setup for higher RPM power. The truck camshafts are designed for low end power, which is what you need to get weight moving. Application makes a big difference.

An auto trans gives you a bit of a break, since you can match the converter to the camshaft, but what I hear from the guys that wheel, a higher stall converter really isn't optimal. So you end up back to the "smaller" cam which makes superior low end torque. If you've got desktop dyno, you can use that to see the difference different cam grinds make. Unfortunately the dyno graph starts at 2000RPM, so you can only guess what's happening in the RPM's where you might be crawling at. Engine Analyzer starts a 0RPM I think, but it's not as commonly used as Desktop Dyno. (I'm not talking exact numbers here, just the cause/effect of different cam grinds, which both programs accurately depict)

I think you'll have a very hard time getting a "flat" torque curve with any cam we are going to be using. Looking at the "curve" of the LS/LT1 motors, and then the cam specs, I doubt many of us run cams anywhere near what GM does to keep the curve as flat as it is. Lobe seperations somewhere in the range of 118* or something IIRC. I'm not a cam expert, I don't completely understand the relationship between all the numbers and how the curve ends up, only know that the stock cams, at least later on, produce a very flat curve, whereas the stuff we normally see or use has a marked peak and falls off pretty quick before and after the peak.

Peak power is really meaningless (IMO) unless that's where you run the engine all the time, such as racing or mud.

I'm surprised the ZZ4 cam is that much really, they're obviously takeouts from crate motors, so I'd think they'd be even less. Just speculation. Even a used cam (perhaps check thirdgen.org classifieds) is ok with roller lifters, so you might be able to find something MUCH less, which for $50 would be almost worth it just to try.

I spent a lot of time looking for my cam, and I'm pretty happy with how strong the engine runs. I've got compliments. I do feel though (and the TPI has some bearing on this) that the top end might be compromised a bit too much. I drive mainly on the street, and I like accelerating...the truck starts out pretty good, but I don't feel the power up top quite as much as I'd like, since the 465 needs some serious engine RPM's to try and overcome that gear spacing. Again, less of an issue with an auto trans.

Here's the graph, the cam specs are accurate, if you can read them. As you can tell, I was much more concerned with low end than upper end, based on my 3.42's and 33" tires. Comp just didn't have a dual pattern roller with 112* lobe seperation, and it made less power in simulations than the Crane I used. No off the shelf grind matched the Crane.

1569K5TPI350.jpg
 
Thanks for the post.. I have desktop dyno 2000....
how did you set all the numbers below the cam specs?? when I opened it up I didnt have any - (negative) numbers......
 
I *believe* those are calculated by the data that you can put in, but I can't recall exactly...I haven't used that program in over a year.
 
CyberSniper said:

yeah, the XR258-HR is great for a truck, pretty much all the power below 5000RPM

I have a Comp Cams XR258-HR for sale if anyone wants it, $150 shipped in the 48, less than 3000 miles on it(4 oil changes though, lol), I pulled it because I got a deal on a larger Comp Cam(XR270-HR)
 
Call all of the camshaft manufacturers that you can find the phone number for.
Most of them have 800 numbers.
They will ask a pile of questions and then determine which of their cams are/is best for you.
Gears, tire size, transmission etc.
Then you have to make your decision.

Most of these people are very smart when it comes to camshafts but be sure to call around.
 
dave_90_blazer said:
yeah, the XR258-HR is great for a truck, pretty much all the power below 5000RPM

I have a Comp Cams XR258-HR for sale if anyone wants it, $150 shipped in the 48, less than 3000 miles on it(4 oil changes though, lol), I pulled it because I got a deal on a larger Comp Cam(XR270-HR)

since I am not looking for a cam that is computer friendly...this would be a good choice???

also from what you are showing with those dyno sheets...
how would this one be?
street friendly? alot of torque at low rpm...
12-423-8
http://www.compcams.com/information/Products/Camshafts/DynoSheets/XR276HR-10_001.asp
xr276.JPG



you know what... I am going to call comp cams tomorrow... tell them what I have and what I want....

also I have desktop dyno 2003, camdisk 2 for desktop dyno 2000 and desktop dyno heads... gonna play around with them and call comp cams and see what they think....thanks all for the replies...
 
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I used to run a XE274H on my 383 toy. I had no vacuum assist anything and it was a good thing because at idle it had very low vacuum. Like around 8" at idle (600rpm). It was pretty lopey. There's no way I'd have been able to run stock valvesprings with it either. Between the lift and the aggressive ramp it'd make funny faces at stock valvesprings.
 
Stock heads will not allow the larger camshafts to really shine....

If you are running stock heads, stick with the smaller grinds. Your most potential for power is in the heads themselves. Many of us throw $200 here and there trying to make more power, when if we just saved all that for better heads we would be way ahead of the game....
 
Very good point, there is a LOT to be said about getting better heads.

You already mention an intake "upgrade", if that hasn't been puchased yet, maybe consider something like the pro-topline Vortec replacements. (they would probably be my choice for a mild engine build, if doing carbed and emissions exempt) If you look around, you can get them for $500/pr, plus a $150 Edelbrock Vortec carbed intake, and short of the guided rockers (which I have no idea of price) you will be good to go.

Still need a cam, but they will blow any of the "earlier" stock heads out of the water, so it's not like you are wasting your money on them.
 
Here's a post with all the ZZ4 cam ( camshaft ) specs, maybe this will help some folks in the future. Of course, you can't search the board for "ZZ4". :(

ZZ4 cam specs
 
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