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Discussion Starter #1
Changed the cam the other day on my 350..515lift and 246 duration..2200 stall and 373 for gears..Rpm manifold and edelbrock 750 carb...My problem is it just doesn't seem rev up very fast and doesn't seem to pull as hard as I expected...I replaced the heads at the same time with some 64cc heads...but not sure of the chamber size....Also when I check the timing with the light It doesn't seem to have any vacuum timing at idle..and when I rev it the timing comes in slow...I am realy confussed..I am wondering if the heads aren't flowing enough for the cam...Need your help guys...Thanks in advance.....
 

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What caught my attention is you said it doesn't seem to have any vacuum timing at idle?? When setting your initial timing, you should disconnect the vacuum advance line and plug the vacuum port on the carb. Then set your initial timing.
 

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Is 246 duration at .050? If so you will not show much vac. on a gauge at idle. Set your time with vac advance hose off and plugged. With this cam start with about 14 intial and work up from there until starter will not crank engine easily and back off a few degrees. This will give you a starting point.Don't worry about vac advance timing unless you are worried about gas milage.
 

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I put a 234/242 cam in my 454 and I have to go with a 3000 stall. I am wondering if your stall is too low.

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Bob
Garnet Red 69/SS396/TH400/355 Posi
94 HD Dyna Wideglide
 

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Believe me , with that cam and that 2200 stall, it is not going to rap up quickly since you are making it work at a much lower RPM than it was designed for. You need a 3500 stall. You also need at least 10:1 compression to maintain adequate cylinder pressure. 3.73's are not exactly a match for the new cam either. You need 4.10's.

You should get rid of the vacuum advance and run streight mechanicle. You will probably need to recurve the distributor. Tell us about the advance curve. What is the initial? What is the total? When is it all in by?

What heads do you have?



[This message has been edited by mutant 68 (edited 03-31-2002).]
 

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Discussion Starter #6
I am using a set of GM 64cc heads..202/ 160..also I am running 12 degrees at idle with 33 total in at 2800rpm....Also I can't seem to get it to idle under 1100rpm is this normal.thanks
 

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Yes 1100 is normal for that big of a cam. What kind GM heads with 2.02/1.6 valves, do you have a casting number?

That's pretty serious mismatch with that cam and 2200 stall - that cam will want some big port heads and at least 3000-3500 rpm stall. Also a single plane manifold and big exhaust. If this is in a 350 the cam's power band will probably be from around 3500 to 7000 RPM - you need the other parts to make it work or you need to switch back to a smaller cam.

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68 Camaro, 383 small block with TH350 trans. 11.98's at 111mph and never trailered.
 

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Yes, I agree with others, you need alotta convertor, starting at 3500.

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Everett 68/350/PG/11.90/115mph
 

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Discussion Starter #9
The cam spec sheet claims the power band to be 2500 6500..The stall is 2200 with 373 on the rear...I am trying to avoid a higher stall..As I am told it will generate alot more heat..

Also it seems alot better since I timed it using someones above mention procedure...Advanced it untill it kicked back then backed it off...any more thoughts..Thanks guys I realy appreciate all the info
 

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Did you change your springs under your metering rods, the way to tell if you need a weeker spring on an eldelbrock is lower your idle speed and listen for the rods to rattle in the carb, hope this helps your idle problem.
 

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<BLOCKQUOTE>quote:</font><HR>Originally posted by flattop:
Did you change your springs under your metering rods, the way to tell if you need a weeker spring on an eldelbrock is lower your idle speed and listen for the rods to rattle in the carb, hope this helps your idle problem.<HR></BLOCKQUOTE>

I'll be damned , so that's what that noise is. Please elaborate on this. I have stepped up to the silver spring and with the idle set low the carb sounds like a tin can full of marbles.

I have some idle issues, maybe I should go the opposite direction with regard to springs?

-Funk


[This message has been edited by CFunK (edited 04-01-2002).]

[This message has been edited by CFunK (edited 04-01-2002).]
 

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Hey cfunk, Just start out with weakest spring that will stay down at Idle, I always just loosen the screw a little, and turn the cap 90 degrees and tighten so I can see whats going on in there,then set your timing, adjust idle mixture, and set idle speed, then select a spring that only rises when the throttle is opened quickly, now your ready to fine tune. hope this helps.
 
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