tuning a 284/484 with a 114 split.

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J

jaxle

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my off idle response is pathetic.

i have a 360
650 demon
ported eddy heads
2600 hundred stall in a 727 with good work done to it.

what kind of idle speed should i get out of this cam?
is there something i can read?

right now i want to "blame" the carb but really i want to know what i should be aiming for to get this thing to idle nice and respond like a champ.

an initial timing "zone"
an idle RPM "zone"

i can set it up nice and then come putting it in gear and thats were everything falls apart.
idle lugs
fuel ratio leans
response turns to crap
ya, no good.

so i tune it in gear and then put it in park and zing! the rpm is like 1100 hundred. is this right?
 
Initial timing as much as the starter will handle. I'd get it in the 14-18 range.

Then check total so you don't exceed maybe 34*. You may have to limit the mechanical advance in the distributor.
 
yes check the timming first. is that a holley if it is how far out are your mixture screws if they more than 2 turns or make no differance where they are set then we need to work on your carb. large cams require more air to idle but opening the front idle speed to far pulls the throttle blades out of the fuel transfer ports. the fix is open the secondarys there is a idle stop on all holleys its usually up side down in the base plate you can take it out and put it in the right direction. i just carefully bend the stopper arm this will allow you to shut the fronts down to where they need to be. mixture screws should work best around 1 to 2 turns out any more than that this is usually the fix. it will be a try and error thing
 
284 aint much cam, check that you have total advance fully in by 2000 rpm,initials used to start a fresh rebuilt engine, always total 35 degrees advance fully in by 2000 rpm.
 
What vehicle are you running this combo in? What is your rear end gearing and tire size? Vehicle weight and gearing will make a huge difference in the bottom end power with that cam.

I've run that same cam in my 66 Vart for the past 15+ years, and it idles great at 750RPM, and has approximately 14" of vacuum. My 360 still has the stock pistons and compression ratio, a set of 915 "J" Heads with a 3-angle valve job, and an old LD340 manifold with a 625 AFB. Until I started my restification, I was running a 7.25" diffy with 2.94 gears and a 727 with a B&M shift kit - not an ideal combination with that cam, but the car is very light. Off the line, most VW's would take me across the light, but once I got to about 2800 RPM, move over, I'm comin' through. It would pull like Jack the Bear once I got into the power band of the cam. In my case, the lack of low end probably helped that old 7.25" rear end to live as long as it did, and we sure ate up a lot of Chivvy's and Ferds over the years. :)

So, with that nostalgia out of the way, I doubt it's your cam that causing your tuning problems. Look at timing, carb, and especially look for a vacuum leak, either external, or underneath the intake manifold. Good luck and keep us posted on your situation.
 
ask questions, Its my honor to help out if anyone doesnt understand my posts. take care friends
 
dang, half my replies didnt go through, feel free to ask tho, regards
 
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