Time for a cam

[miller]

So, here's where I am. Looking for numbers I need to chose one.

64 Sport Fury, 440, 727 auto. Weight around 3400 lbs.

Tires-26"
Rear-8 3/4, 3.55 gears with sure-grip

Looking to run 93 octane, just a street car. What's this about fuel running hot these days?
Probably looking at a 650-700 cfm AFB, on the iron intake. Iron exhaust.

440 w/steel crank, KB237 +20 pistons, LY rods. 906 heads, and block has been decked .005.

Those pistons sit .003 down in the holes, with 5cc figured on the valve reliefs. Used 88cc to calculate the CR.
Figured with .045 head gaskets (in the gasket set I bought), but also punched numbers using a
.030 gasket. Why? I'm looking at .005 block decking, plus .005-.006 off the heads. Stock head gaskets (steel) about .021...right?
Adding .010 cuts, a .030 head gasket would keep all in order.

With a .045 gasket...CR=9.609:1
With a .030 gasket...CR=9.945:1

What cam numbers should I be looking for?
Thanks, guys!

 

[eric383]

If you like playing with specs try this.
http://www.camquest.com/
Otherwise send some e mails to some cam manufacturers for their recommendations. You may have to change out the torque convertor also. Good luck.

 

[miller]

Understand. I'll have a look.

Didn't think to mention valve train. Looking at using my 'stock' valve train, off my magnum motor. One issue is the push rod length, that the cuts/head gasket should keep in line. Red painted springs. Plan to completely check them out. Stamped 1.5 rockers.

Anybody use Crower cams? Kinda looking at #32243...

 

[miller]

Going to contact Crower.

Think 32243 is too much...check on 32241...and see what they say.

 

[miller]

For the heck of it. Ordered a Crower 32241.

lsa 112, @50 220/223, lift 478/486. Out of stock, so their grinding it now. Also gonna call today, to check on the full groove on #4 journal. Unless #4 cam bearing is grooved, that's the only way to get full flow oil to both rocker banks.

 

[wyrmrider]

How did you come up with those pistons
no quench
KB makes special pistons for open chamber chrysler heads
get a cam ground especially for .904 lifter
comp/ lunati/ etc are mostly chevy grinds unless special order from the back of the catalogue
crower has some of each but good selection from cam spec sheet also Engle

 

[miller]

Heck, I bought those KB237s 12 or so years ago. Just after I picked up the motor. Yeah, no quench.

Numbers using that Crower cam, Static C/R 9.945, Dynamic C/R 8.564, using a .030 head gasket. Of course, plan to run it on 93 octane. Usual deal...gonna blow or go.

Yeah, I know what diameter lifter. The cam is designed for the 440.

 

[lewtot184]

seriously doubt those pistons will work with pump gas. no quench, short cam. i use the 184's with open chamber heads and pump gas; no issues.

 

[miller]

Guess I'm going to find out. Though I really appreciate the few comments.

Last motor I built was a 383 w/906 heads, though used flat top pistons, no problems at all. But, that was 20 years ago. Have things changed that much? Still junky gas back then, too.

Compression numbers seem to come in within limits, for the gas, from my reading on all this stuff. Might need to toss a cool can into the mix, besides good cam/ignition timing. Times gonna tell.

If I had known about things, would have stuck with regular SpeedPro flat tops, and been done with it. First time using KBs.

Thanks, guys!

 

[wyrmrider]

get the ring gap on the KB's correct
you essentially have a 6 pack build
with that deck 11-11.5:1- did you cc the heads, exhaust seats, guides?

you really do not need more oil to the rockers
drill through the thrust in the web.040 then brg .060 and chamfer to positive oil the thrust (to the oil feed hole
you can also use a brg scraper to open up the parting line(s) to the thrust side
you can put a couple of .040 holes in the galley plugs to the cam gear to oil the cam and bleed any trapped air
you can also pressure lube the cam/ dist gear
That crower grind is at lest 25 years old and not really pushing the .904 lifter
but it at least has enough duration to bleed off some of the dynamic compression
you can always install it straight up if you have too much
cheers

 

[miller]

Thanks for that, wyrmrider!

With a .045 gasket...CR=9.609:1
With a .030 gasket...CR=9.945:1
(as mentioned in my first post) Also that the block has been decked .005, probably .005 on the 906 heads. From the way things are going, my heads are dead, as far as I'm concerned. Four intake valves locked solid in the guides, way too much rust in some of the ports. Think I'm looking at cracks in the water jacket.

The cam has the full grooved #4 journal, meaning full time oiling to both rocker banks. Of course, all well cleaned ports, and such. Simply consider that normal Mopar motor building. Wanted to keep the 'stock' Magnum valve train, since the only Magnum thing about it is the slightly heavier springs, but fine for the cam. Just have to make sure of pressures and clearances!

Yes sir, KBs ring gaps right. The KBs also call for a miminum .040 clearance. Using 906s, and considering Ma Mopar didn't give a flip about quench back then, and all still worked...affected my thinking. Gonna be a we'll see.

Know I've gotta dip into heavy-duty understanding on the cam timing, but unless something says otherwise, will start with a straight up timing, and check all my numbers. All compression values are going to set the pace.

 

[1wild&crazyguy]

Miller, why do you think you need full time oiling to the top end?
Ive always been fine with the top end oiling, it's spinning the no.6 rod bearings thats bit me, they need more oiling over 7000 rpm.

 

[miller]

Miller, why do you think you need full time oiling to the top end?

I suppose it's the old man in me. Besides the lubricating end of oiling, it's the needed (full-time) oil 'pressure', that those parts and pieces must have to live.

It is...you've got two long tubes you've got to keep filled with a pressurized supply of oil, to feed your rockers, no matter what kind you have. From the rocker overflow, into the tappet valley, the cam lobes also get oiled down...sure don't see any prob with that. What your getting on those setups is off/on oiling (pressure).
You have full time oiling to your bearings...why not the rest of your parts? Any and all parts hold up from floating on a coat of oil...

Quicky on the cam I ordered...
Crower has said these grinds have been 'modernized', along with 4 degrees advance ground into the cam.

- - - Updated - - -

Ive always been fine with the top end oiling, it's spinning the no.6 rod bearings thats bit me, they need more oiling over 7000 rpm.

You using full groove rod bearings??

 

[Meep-Meep]

Your combo begs for a 112 LSA cam with about 272 deg duration. To preserve valve train stability always run the iron adjustable rockers with 3/8" pushrods whenever I use higher than stock springs. Or some other strong rocker if the old adjustables aren't available. Fully grooved #4 cam journal might help to oil the rockers that are working against higher than stock spring pressures. Stock intake and exhaust, especially the exhaust, will limit what you will get out of the engine. Keep the cam on the mild side. Also, I'm running the KB 237's with 915 heads and yield 10.1: CR. That is too much for pump 91 or even 93 but runs great when spiked 110. Using the 906's with a near zero deck 237 piston isn't going to hurt you. You still have quench, just not at .040". Factory 440 6 BBL ran 906's with zero deck pistons.

 

[IQ52]

You will not believe the amount of oil that floods the top of the engine when using a full groove around the number 4 cam journal. All that excess oil flows into the valley onto the cam and then on the crankshaft and is thrown on the cylinder walls. The oil rings fight like heck to control the excess oil.

The clocked oil holes in the original #4 cam journal have plenty enough oil for the top of the engine.

 

[wyrmrider]

. Using the 906's with a near zero deck 237 piston isn't going to hurt you. You still have quench, just not at .040". Factory 440 6 BBL ran 906's with zero deck pistons.

you did fine till you got to "you still have quench" true with 915 no quench with 906
factory 6 pack pistons were down the hole not zero deck unless deck was decked
I'm running mine +.015 (out) with the block decked about .030- really way off block
but I cut a big D dish to get 9:1 with 915 heads
IMHO 906 heads do not work with today's gas and with low compression all they make is heat

 

[IQ52]

"all they make is heat" and what is "low compression"?

Please do explain.

 

[Meep-Meep]

you did fine till you got to "you still have quench" true with 915 no quench with 906
factory 6 pack pistons were down the hole not zero deck unless deck was decked
I'm running mine +.015 (out) with the block decked about .030- really way off block
but I cut a big D dish to get 9:1 with 915 heads
IMHO 906 heads do not work with today's gas and with low compression all they make is heat

I disagree. The 906 chamber is not a symmetrical shape. No quench at all would mean the top of the piston to the chamber is the same distance all around. The 906 head is a wedge shape so the gap on one side is closer to the piston than the other. It's also important to make sure the flame gets in to burn everything completely. The approximate difference in quench gap is .040" to .090" and I bet that's enough to produce some swirl in the chamber. The amount of swirl may vary but is that extra .050" going to completely kill the combo? I seriously doubt it. If you want to control pinging then it's best to start with the appropriate compression ratio and cylinder pressure for the available fuel. And that fact is inarguable.

Regarding the heat comment I'll suggest the higher compression is what makes it - heat that is.

I believe the 6 BBL piston is a 2.065" compression distance, and according to blueprint specs, that comes out to zero deck. Sure the machine tolerances will often stack up in the wrong direction so having that piston down in the hole a bit will be possible, but not -.090" like on a Magnum engine.

 

[miller]

You will not believe the amount of oil that floods the top of the engine when using a full groove around the number 4 cam journal. All that excess oil flows into the valley onto the cam and then on the crankshaft and is thrown on the cylinder walls. The oil rings fight like heck to control the excess oil.

The clocked oil holes in the original #4 cam journal have plenty enough oil for the top of the engine.

You like your meat dry, too? Sorry. But, that's where different opinions come into play. Either one can be correct. Simply matters to each, what they want.

That #4 cam journal is the only oil feed for the top end...rockers, springs, valves. Oil doesn't only lube, it carries away heat. And, I don't care if you use lowly, cheap, crappy, stamped rockers, or some of your high-dollar stuff, they are all designed to run on full-time oil. Of course, this is just my opinion...not worth much.
I've seen too many parts starved for oil, flat wore out, wondering why they went away?? I'll take positive oil over pulsating oil any day of the week.

On the head bit...(and yeah, I can be off my rocker), I'm looking at the compression issue, against the fuel. Numbers come up real close, as far as what is said to be needed.

Hiya, Meep...I ran one of the cams you like in my son's 69 Charger. 383 Hipo. Yeah, ran real good, though with 323 gears, and the rest of the combo, it could use help on the bottom end. Sure didn't worry about whip-lash, but a kick in the rear over 45 mph.

 

[miller]

Your combo begs for a 112 LSA cam with about 272 deg duration.

Numbers off the 32241 cam card-

Intake- Duration 267, Lift .477
Exhaust- Duration 271, Lift .486

Lobe Sep- 112 degrees, Duration @50 Int 220/Exh 222

At any rate, it'll plug the hole. Slightly peeved about the #4 journal...since I contacted Crower before they even began to grind it. Wanted to be sure the journal had a oiling groove, and was told yeah. My #4 bearing doesn't have a groove. But my #1 does! Why??? Guess I'm getting too old for this crap.
Came in Friday...hell no, no groove. No prob. Local machine shop gonna dig one in for me. One way, or the other.

And yeah, that 'extra' oil I'll be getting topside, won't bother me one bit, while it's oiling up my cam lobes.