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Discussion Starter #1
Narrowed my choice down to two cams, but I'm not sure which is the best choice.

Engine is as follows:

'69 327
late-90s 300hp/350 64cc crate motor heads machined for 2.02/1.60 valve (NOT vortecs)
1-1/2" Hedman headers 3" collector w/ x-pipe & 2.5" exhaust
ZZ4 Intake manifold
Q-jet carb
~9.25 CR (.028" gasket, .025" deck, 6cc valve reliefs)

Car is a '65 Nova ~3100 lbs, Muncie M20, 3.08 gears, 25.6" tall tire

Looking at Reed cams

264/272, 214/218 @ 050", .450"/.460", 110 LSA
or
272/276, 218/223 @ .050", .460/.470", 110 LSA

Goals are:

strong midrange (2000-5000 rpm), with Peak HP between 5000-5500 rpm.
5500 Max RPM (I don't want to buzz it high)
Reasonable fuel economy
Idle quality not really important

I leaning towards the smaller of the two cams. Just wondering what others would choose.

Thanks!
 

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Generetic run of Dyno 2000 shows the smaller cam winning the torque battle hands down and the HP difference with the larger cam only a few more at 5k+ so I like the smaller:thumbsup:
 

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Smaller cam...

Ditch the 3.08's for some 3.36's or 3.55's, then the bigger cam.

And I'd pull the heads off and install a pair of .015" thick shim headgaskets. You are leaving power on the table b/c of too wide a quench, imho....

pdq67
 

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I'd bring the collector size down to 2-1/4" or so to help with the secondary scavenging. A 3" collector on a set of 1-1/2" primaries is like no collector at all.
 

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Sounds like you want a Cruiser with Good gas Mileage and still lay a Patch. I say the 264H-10. The 3.08's will love the cam and keep your DCR respectable for Pump Gas. I love my 3.08's for HWY Cruising. We are not all Street and Strip Drag. Just wait and look at the face of someone running 3.73's when you shift down to 2nd at 60mph and blow their doors off then disappear over the horizon while they stop to fill up. - lol
 

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The little one. It is little more aggressive than first glance makes you think. It is a 50° intensity on the intake, where the bigger one is a 54° intensity(advertized minus at50#). Both are pretty fast for FT Hydraulic, usually see intensities up closer to 60.
 

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Discussion Starter #7
Thanks, guys. I was thinking the small cam would be best.

Next question:

I have a Performer RPM Q-jet manifold, and the ZZ4 manifold available. Which would work best on the above combo?
 

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I would use the larger cam. I have a 350 with 9.3 static compression. I also have a Crane cam with 216-228 at .050 with a 112 lobe separation. I have to run 93 octane to prevent pinging when lugging or going up a steep hill. This is also in a standard transmission. Total timing is 36 degrees in at 2500 with the adjustable vacuum advance pulling in 12 more at cruise. The adjustable advance is set to retard at 10 inches of vacuum. The 214 cam's intake valve closing will be 3-4 degrees earlier than mine with any kind of advance degreed in the cam.

Pumping compression is 185 and vacuum is 16 at 850 rpm. The engine has loads of low end torque and will pull down without surgeing or bucking.

The only reason I would use the bigger cam is insurance against to much dynamic compression. I also feel the larger cam and the RPM intake would be worth 10-15 horsepower from 4500 on up without giving up much on the bottom.
 

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On a 327, I would stay below 218 degree's duration at .050. The short stroke does not seem to like big cams with small heads like the double humps. So use the smaller one.
 

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Discussion Starter #10
Sleeper.... detonation is one of my concerns with the smaller cam. Are you sure your 350 is 9.3:1? What CC heads, gasket, and deck height are you using?

My only fear with the larger cam is that it will kill all bottom end power, and hurt mpg too. I wonder if it will even make more power from 4000-5500 since I have 'small' ~160cc heads?

Anyone have an opinion on intake manifolds?
 

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I know it's probably not much help but, I've always heard when in doubt on cams, go with the smaller one...Did you get a recommendation from Reed cams on your setup?
 

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Sleeper.... detonation is one of my concerns with the smaller cam. Are you sure your 350 is 9.3:1? What CC heads, gasket, and deck height are you using?

My only fear with the larger cam is that it will kill all bottom end power, and hurt mpg too. I wonder if it will even make more power from 4000-5500 since I have 'small' ~160cc heads?

Anyone have an opinion on intake manifolds?
Pistons are the flat tops with the 4 eyebrows. The eyebrows are 1.5 cc each for a total of 6. Gasket is 1003 FelPro .041x4.167, heads are the 993 milled to 72.5 cc, block has been decked to .005, bore is 4.03 and stroke is 3.48. I degreed the cam to close the intake valve at 108 centerline. All sharp edges and ridges were smoothed from the combustion chambers.

If you use the small cam and have pinging problems you will have to retard your timing maybe 4 degrees to correct it. I tried 38 on mine and it was a little to much. I wound up at the 36 degree after a couple of months trial and error. I also tried having all advance in at 2200 and that did not work either. I would rather run a little larger cam and run my timing correct than having to retard it.

I think for your use the smaller cam is best suited if detonation does not occur. Just trying to share what I have worked through with a very similar combo. Also the 327 will have a longer rod ratio that means the piston will stay in the TDC area a little longer than with the 350, thus slightly increasing the odds for detonation. Can you get your compression to about 8.75? That would work great with the smaller cam. I know my dynamic compression figures about 7.5 and everyone says you can run up to 8.00. I can't with this engine, someone else might can.
 

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Discussion Starter #13
I know it's probably not much help but, I've always heard when in doubt on cams, go with the smaller one...Did you get a recommendation from Reed cams on your setup?
Reed says either one would be great. They said go for the 272/276 if I want a bit of idle sound, and more high rpm hp. If I want gas milage and maximum drivability, they said the 264 would work.

The reason I am asking here, is that I wanted to get opinions from other 327 owners. Everyone says "go small" on a 327. When I talked to Dennis at Reed, the 272/276 was his first recommendation. He said that I can go wrong with either choice... just depends on what my priorities are.

Pistons are the flat tops with the 4 eyebrows. The eyebrows are 1.5 cc each for a total of 6. Gasket is 1003 FelPro .041x4.167, heads are the 993 milled to 72.5 cc, block has been decked to .005, bore is 4.03 and stroke is 3.48. I degreed the cam to close the intake valve at 108 centerline. All sharp edges and ridges were smoothed from the combustion chambers.
Thanks for sharing all the details. I would have never guessed that the 272/284 Crane would ping in a 9.3:1 350.
 

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I don't think you'll have any detonation problems with either cam. Just don't try to bring in too much advance too fast.
 

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John65Nova, can you tell us what numbers the heads are ?
 

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Discussion Starter #16
They are 14096217 heads. These are bascially the same as the 14101083 used on 1988-1992 Z28 TPI 350 engines. TPI engines had the angles center intake manifold holes - Mine do not.

These were from a late-1990's 300hp/350 crate engine. This is the engine that GM offered BEFORE the current Vortec 330hp/350 "HO" engine. Specs on the '300 hp' engine were the same as the current "HO" 330hp engine, but it used these heads instead of Vortecs.

They are centerbolt, 64CC chamber (shaped just like the Aluminum ZZ4 head Chamber), straight plug. They do not have the "swirl ramp" in the bowl like other centerbolt truck heads.

The particular set that I have has been outfitted with LT4 retainers / springs, and 2.02/1.60 valves.
 

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I ran a couple of DD2000 syms and those cams are pretty close to each other. The small one has a little more HP and the bigger one has a little more torque.

264/272 = 318 hp 366 tq

272/276 = 313 hp 372 tq

Take the sym. anyway you want. It may be optimistic or not !
 

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That's only the peaks. How about the average over the operating range?
 

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Sorry, I didn't save the info... maybe 1/23 I can get a chance to run again. I would really like to get flow numbers, on those heads so the sym. would have more accuracy. With out them it is really a guesstimate.
 

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Discussion Starter #20
onovakind... I'm guessing EA3.0 sees this different?

My guess is that the smaller of the 2 cams has more area under the curve in the 2500-5500 rpm range, making it better suited for a street car w/ 3.08 gears.

TJS69... thanks for the sim!
 
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