I was just wondering if i'm chasing a ghost or not??? This is what i got..350,L-83 bottom,96 cast iron vortech 64cc,full roller rockers 1.6,head gasket compressed .040,alum. intake dual plain...performer,holley 650,primary jets@ 70,metering plate on back bowl,power valve 6.5,vac @ idle in park 17, 700r4 w /fairbanks switch locking up converter only in fourth gear.Hooker long tuned headers 4inch pipes,alum rad....still stock gears at the moment 272 going soon to 373...This car wants to hold a idle @ 1000 rpm in park,550,600 in gear is this normal for this type set up??? I have ck for vac. leaks with wd-40 and using propane too found nothing...chokes down then kills itself when closing off airhorn on carb.So it doesn't act like i vac leak....could dist. advance springs be to lite? Causing a high idle??? what gives...:huh: the Carb had 64 jet in primary bowl but the plugs show that it was running very lean so i installed the 70's thought that might help.with that.
Where does your 350 idle @ in park/gear?
- Thread starter Miss Mako
- Start date
Ozzy
Well-known member
Mine will idle where ever it is at when it is not in motion :bounce:
Now if you want to know idle speed rpm's, mine are 700-800, stock LS1engine and trans.
Now if you want to know idle speed rpm's, mine are 700-800, stock LS1engine and trans.
damoroso
Well-known member
What do you think it should idle at in gear? 550-600 actually sounds just a bit low. Like Ozzy's LS1, my BB idles at about 950-1000 in park, and 750 in gear...
Twin_Turbo
Der Maulwurf
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- Mar 5, 2008
- Messages
- 7,579
700-800rpm
larrywalk
Well-known member
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- Jan 2, 2009
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- 78
Your idle rpm is largely dependent on the stall speed of the torque converter - the tighter the converter, the greater the rpm difference between no-load idle rpm (neutral) and in gear.
Another thing to decrease the difference...
Check the point at which the centrifugal advance starts. If it starts advancing at 700 rpm, the timing will advance beyond initial for idle at 1100, but when placed in gear, the additional load will pull down the rpm and decrease the timing, slowing the engine further. A good strategy to use shorter dist springs to increase the preload on the flyweights to prevent the timing from advancing until ~1200 rpm, and setting the initial timing to about 14 degrees. The net result is that there will be less difference between in-gear and out-of-gear idle rpms.
You will also want to limit the centrifugal advance to keep the maximum timing to 36 degrees (measured while the vacuum advance is disconnected).
Another thing to decrease the difference...
Check the point at which the centrifugal advance starts. If it starts advancing at 700 rpm, the timing will advance beyond initial for idle at 1100, but when placed in gear, the additional load will pull down the rpm and decrease the timing, slowing the engine further. A good strategy to use shorter dist springs to increase the preload on the flyweights to prevent the timing from advancing until ~1200 rpm, and setting the initial timing to about 14 degrees. The net result is that there will be less difference between in-gear and out-of-gear idle rpms.
You will also want to limit the centrifugal advance to keep the maximum timing to 36 degrees (measured while the vacuum advance is disconnected).
I found the problem!!!!
when i rebuilt the carb...i got everytihing rt. but the sec. stop /lock out...had it slightly opened while the throttle shaft was closed....After i made that right...it showed up a small vac. leak at brake booster fitting .Idles smooth now .Not racing or jumping around...Yeah,two days of over looking a simply mistake!:yahoo:
when i rebuilt the carb...i got everytihing rt. but the sec. stop /lock out...had it slightly opened while the throttle shaft was closed....After i made that right...it showed up a small vac. leak at brake booster fitting .Idles smooth now .Not racing or jumping around...Yeah,two days of over looking a simply mistake!:yahoo: