Re: Cam ideas for a 493: Idle to 5800 rpm range
[Re: Kern Dog]
#1635853
06/22/14 06:56 PM
06/22/14 06:56 PM
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Joined: Jan 2003
Posts: 31,078 Oregon
AndyF
I Win
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I Win
Joined: Jan 2003
Posts: 31,078
Oregon
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Another reference point is to look up the cam specs on the Chevy 502 crate engine. The Chevy engineers went with a very small camshaft on that engine but if you look at the torque curve and the HP numbers on the dyno sheets you'll see that it is a very good street engine. Probably something really close to what you're asking for. The moral of the story is that the camshaft doesn't want to be very large for off-idle performance.
Last edited by AndyF; 06/22/14 11:18 PM.
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Re: Cam ideas for a 493: Idle to 5800 rpm range
[Re: forphorty]
#1635854
06/22/14 10:13 PM
06/22/14 10:13 PM
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Joined: Feb 2010
Posts: 18,493 Granite Bay CA
Kern Dog
OP
Striving for excellence
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OP
Striving for excellence
Joined: Feb 2010
Posts: 18,493
Granite Bay CA
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Quote:
My memory is faulty. Do you have a TCI converter? If so, that may be your problem.
No, my converter was built here in Sacramento by D&P products.
Regarding Andy's suggestion: Is/are cubic inches the main criteria for accurate info comparison between different engines? How much does Bore, Stroke and cylinder head design affect cam selection? I'm not doubting anyone here as I see that Andy has an excellent rep. I'm just trying to learn more.
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Re: Cam ideas for a 493: Idle to 5800 rpm range
[Re: Kern Dog]
#1635855
06/23/14 07:35 PM
06/23/14 07:35 PM
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Joined: Nov 2005
Posts: 3,456 Fly Over States
PHJ426
master
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master
Joined: Nov 2005
Posts: 3,456
Fly Over States
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Quote:
Thanks again guys. Part of me wonders if most of the lazy feel is due to the torque converter. I've driven cars and trucks that feel really snappy immediately from idle speed. One main concern though is the risk of going to a converter that is too tight. I can idle the engine down to 800 rpms or less in neutral but that results in too low when in drive. Am I right that an engine with more torque tends to increase the stall speed? By this I mean, (Just for grins) would a stock 12" converter stall higher with my engine than it would in a mild 360? The reason I ask is because I have 3 or 4 727 converters in my stash. One is an 11" unit. For very little money I could try a different converter to see what effect it has.
Are these older torque convertors? Reason I ask is the torque convter tech has changed in the last 15 years or so?
The 9.5" Ultimate Convertor Concepts in my heavy Road Runner had power out of the gate, mid and top end all with a 2.94 gear and 275/60R15 tires.
I didn't see what heads your running with your stroker? My engine was the older 508 RB stroker built by Bobby Streetwize here on the the board...with 4.25" crank and Stage 6 heads (Max Wedge size intake ports). The car had a flat tappet hydraulic lifter cam which most would say was small but it was just my pump gas and go combo. At 55 mph in 3rd mash the throttle and it kicks down to second boiling the tires (granted these were old BF Goodrich T/A's)
Anyway it's important to match your combo and getting advice from one person on a cam, then another persons opinion on the convertor adds alot of variables.
I have purchased some parts from Scott in the past and very happy with his work so when it came time to put the cam and converter package together I just relied on Scott and he came through.
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Re: Cam ideas for a 493: Idle to 5800 rpm range
[Re: PHJ426]
#1635856
06/23/14 07:52 PM
06/23/14 07:52 PM
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Joined: Jun 2006
Posts: 5,167 CT
GTX MATT
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master
Joined: Jun 2006
Posts: 5,167
CT
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Don't screw around, have one custom ground this time
Now I need to pin those needles, got to feel that heat Hear my motor screamin while I'm tearin up the street
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Re: Cam ideas for a 493: Idle to 5800 rpm range
[Re: Kern Dog]
#1635857
06/23/14 08:19 PM
06/23/14 08:19 PM
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Joined: Feb 2005
Posts: 4,321 Prospect, PA
BSB67
master
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master
Joined: Feb 2005
Posts: 4,321
Prospect, PA
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Quote:
I did ask the machinist about that. He said that the guy doing his port work was nervous about digging too deep and cutting through into a water jacket.
sounds like you need a new machinist and head guy.
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Re: Cam ideas for a 493: Idle to 5800 rpm range
[Re: BSB67]
#1635858
06/24/14 12:25 AM
06/24/14 12:25 AM
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Joined: Feb 2010
Posts: 18,493 Granite Bay CA
Kern Dog
OP
Striving for excellence
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OP
Striving for excellence
Joined: Feb 2010
Posts: 18,493
Granite Bay CA
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Quote:
Quote:
I did ask the machinist about that. He said that the guy doing his port work was nervous about digging too deep and cutting through into a water jacket.
sounds like you need a new machinist and head guy.
Maybe so. My machinist does do good work at a fair price. He has never tried to oversell and has never broken anything. I guess he is a jerk.
I'll readily admit that he isn't a race motor builder. He has 30+ years of experience in all sorts of machine work but he is NOT a head porter. That is why he referred me to another guy. I was working out of town and I didn't think that I had many options. I'm curious though: Since the chambers cc'd at 82.5 to 83 ccs, how is it possible to hog out another 7-8 cc's? You cant take it from the edges because that compromises the head gasket seal. If you take it from the middle, the valves and seats will be left sticking out. Is this a common thing? If so, I can't recall hearing it from anyone but you. Thats not a bad thing. I'm not sure if you are the pioneer in that idea or if someone else mentioned it and I missed it. These are Edelbrocks that originally came with the 84cc chambers. If this is actually possible I am actually willing to consider it. This would allow me to keep the short block intact. My pistons are .012 in the hole. If it is possible to get the chambers to 90 cc's and still have the quench pad, I could run a Cometic .027 and have actual quench for the first time. I'll have to look at my compression calculator to see where that would put me. Dang, now you got me thinking again.
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Re: Cam ideas for a 493: Idle to 5800 rpm range
[Re: AndyF]
#1635861
06/24/14 08:50 AM
06/24/14 08:50 AM
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Joined: Feb 2005
Posts: 4,321 Prospect, PA
BSB67
master
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master
Joined: Feb 2005
Posts: 4,321
Prospect, PA
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Quote:
I wouldn't open up the chambers unless you know that there is enough material there. Most cylinder heads do not have any extra material in the chamber. I'm positive that if you call Edelbrock and ask them if their heads can be opened up that much they'll tell you no. Indy would probably say the same thing.
MCH would say yes. Certainly Jeff has. MCH has done them without a problem. A set is on my car. The standard CNC program already takes them to 87 or 88 cc.
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Re: Cam ideas for a 493: Idle to 5800 rpm range
[Re: AndyF]
#1635863
06/24/14 04:02 PM
06/24/14 04:02 PM
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Joined: Apr 2013
Posts: 441 Uranus
strokerchall
mopar
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mopar
Joined: Apr 2013
Posts: 441
Uranus
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my 512 stroked engine was built with a HUGHES HEH3237BL ,it sounds bad with the lopey idle and absolutely shreds the BFG'S,with the 4:10's it will slam your head back at 60mph and lay stripes down the highway at 30-40mph with ease There's several ponies left to unleash...porting the rpm's and going to a single 4barrel,possibly a bigger cam but where does it end
once you've stroked it,you'll wish you stroked it sooner
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Re: Cam ideas for a 493: Idle to 5800 rpm range
[Re: AndyF]
#1635866
06/24/14 11:23 PM
06/24/14 11:23 PM
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Joined: Feb 2010
Posts: 18,493 Granite Bay CA
Kern Dog
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Striving for excellence
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OP
Striving for excellence
Joined: Feb 2010
Posts: 18,493
Granite Bay CA
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Quote:
Perhaps. I've had a couple sets of MCH heads that leaked water in the combustion chamber. There was very little wall thickness left after the porting.
This is what makes me apprehensive. If the heads are hogged out too much and ruined, all is lost and I'd need to start completely over.
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Re: Cam ideas for a 493: Idle to 5800 rpm range
[Re: strokerchall]
#1635867
06/24/14 11:36 PM
06/24/14 11:36 PM
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Joined: Feb 2010
Posts: 18,493 Granite Bay CA
Kern Dog
OP
Striving for excellence
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OP
Striving for excellence
Joined: Feb 2010
Posts: 18,493
Granite Bay CA
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Quote:
my 512 stroked engine was built with a HUGHES HEH3237BL ,it sounds bad with the lopey idle and absolutely shreds the BFG'S,with the 4:10's it will slam your head back at 60mph and lay stripes down the highway at 30-40mph with ease
There's several ponies left to unleash...porting the rpm's and going to a single 4barrel,possibly a bigger cam but where does it end
I just looked at the specs of that cam: http://www.hughesengines.com/Index/products.php?browse=search&search=heh3237bl&partid=21855
VERY impressive. I see you have 19 more cubes yet a cam this small works for you? I like that. I probably dismissed this grind for being too mild when I was contemplating a cam swap last Summer. Stupid me...I have to step in crap to know what it is sometimes! I don't have a preference of hydraulic or solid. I suppose the solids may be better for higher rpms but as stated, I'm not looking to spin this thing to the moon anyway.
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Re: Cam ideas for a 493: Idle to 5800 rpm range
[Re: Kern Dog]
#1635868
06/25/14 05:52 AM
06/25/14 05:52 AM
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Joined: Jan 2007
Posts: 2,431 SK,Canada
gregsrt
top fuel
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top fuel
Joined: Jan 2007
Posts: 2,431
SK,Canada
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If you have adjustable rockers you might as well go solid.
Last edited by gregsrt; 06/25/14 05:53 AM.
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Re: Cam ideas for a 493: Idle to 5800 rpm range
[Re: Kern Dog]
#1635870
06/26/14 08:51 PM
06/26/14 08:51 PM
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Joined: Jan 2007
Posts: 7,664 IN
ahy
master
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master
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Posts: 7,664
IN
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Quote:
Regarding the MP .528 cam Andy was talking about: This cam with my 1.6 rockers moves the lift to .563 before the lash is deducted. .028/.028 lash if I recall. The specs show a 72 degree intake closing. The 241/241 @ .050 seems in line with what might work for me. A 112 LSA means a smoother idle too, right? My current cam has duration of 261/271 @ .050, .558/.578 lift (After lash)and a 108 LSA.
Specs with the .528 and 1.6 rockers are very similar to my MM cam with 1.5 rockers. 241/241 vs 243/243 @.050 and about .55" lift. The 112 LSA mentioned on the .528 would be a bit less prone to detonation vs the 108 on mine. A benefit in your situation.
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