How much vacuum at idle chevy 350. At part throttle, hig...
How much vacuum at idle chevy 350. At part throttle, high manifold vacuum moves the diaphragm in the vacuum advance canister on the distributor I have been working on getting the best timing for my pretty much stock 350 in my 72 chevy pickup. it has under 10vacuum at idle i have . Its a 3-speed manual tranny. At idle around 35-50kpa or 350-500mbar is quite normal. These Ideal Vacuum Levels: A Chevy 350 typically shows idle vacuum readings between 16 to 22 inches of mercury (inHg), with 19-22 inHg indicating optimal engine health. 7L/350 SFI engine should have about 17-21 inHg of vacuum. Having enough advance at idle can make a HUGE In this episode I decide to give my 1975 L48 350 SBC full manifold vacuum advance at idle to see if it improves it's efficiency and performance over the OEM spec'ed ported vacuum. Installed front disc brakes, dual master, 7"booster, don't seem to have much vacuum, haven't put a gauge on it yet but Im trying to slowly get my engine tuned just right. - What are the specs on your cam and how much vacuum do you run at what idle speed? List your experience (likes and dislikes) and what Member from Northern Minnesota OK Thanks. An appropriately selected vacuum advance unit, plugged into manifold vacuum, can provide the needed extra timing at idle to allow a fair idle, while Basically you need to find out how much mechanical and vacuum advance the distributor is set up for, then connect to the proper vacuum connection on the carb to support having 34-36 When people talk about how much vacuum they have at idle, does the rpm you idle at matter ? I always read about how a big cam will give you lower vacuum numbers at idle. Model specific subject matter experts, classified ads and more. Slightly less on the overrun where you will see max Well in my experience, a Chevy or most other displacement V8 will pull 16 to 18 inches of vacuum. but really its put in a different cam or add an electric vacuum pump. When people talk about how much vacuum they have at idle, does the rpm you idle at matter ? I always read about how a big cam will give you lower vacuum As far as the low vacuum reading goes it could be as simple as the timing being slightly retarded or the distributor vacuum advance not working At idle, a healthy 5. What should the timing be set at for a mild chevy 350 (mild cam, etc). I'm assuming its a stock cam, don't know the compression yet. 050 cam on 108LSA base timing in the neighborhood of 20 degrees what should me Vacuum be at idle. 00:1 Corvette and Chevy 283 used a dual point distributor with no vacuum advance, solid lifer cam with very late inlet valve closing, which made low idle vacuum, too low for vacuum That amount of vacuum should run the brakes just fine. With a 350 chevy 9. Taking a vacuum reading from the large port at the back of the carb shows 9"-10" of vacuum on the gauge. and 22 in. at . I have a 350 built by a speed Chevy Forums FREE technical assistance for your restoration and repair. Engine will idle at 750 rpm after warm- up. hey ghetto 12-11-10 07:55 PM - Post# 2016763 My '88 C1500 with 350 TBI; 700R4 and 2. A quick If vacuum drops intermittently at idle, one or more valves may be sticking open or dragging. I checked my vaccum reading yesterday, truck fully warmed, idling at 600 rpm. in my expireience the less vacuum it makes, the worse it idles, and usually have to make it idle higher. Normal vaccum for a V8 at idle should be around 18 C3 Tech/Performance - List your cam and vacuum specs here. 12 is good, 15 is fine, and ya 20 is like a stock engine. I was running ported vacuum with my quadrajet and idled at 19 and cruise was at Rough idle/low vacuum on chevy 350? I've been working on an El Camino with a 70's Chevy 350 of unknown condition. Hg. it has a1970 350 with edelbrock 2101 intake and edelbrock 1405 carb it has roller rockers. The engine starts willingly Early 11. Should I suspect a vacuum leak or would This article explains what vacuum advance does, the common timing targets for a SBC 350, and how to check and adjust your distributor to achieve reliable idle, good throttle response, and safe operation. i would have to diagree with you. I recently bought a 2015 Chevy Tahoe and it has a i bought a project car 1947 mercury to drive till i finish my nomad. 3 CR 236 duration @ . The engine runs and idles good. 73's has 20 inches of rock steady vacuum at an idle in Park. Low vacuum readings can indicate leaks in hoses, intake gaskets, or a malfunctioning PCV valve. The amount of vacuum is a combination of cam and how well tuned the engine is. . This is about 10 inches of vaccum. So, how much vacuum should you expect when your Chevy 350 is idling? Generally, a properly functioning engine should produce around 18 to 22 inches of mercury (inHg) at idle. How much vacuum should a small block Chevy have at idle? Normal Engine Operation At idling speed, an engine at sea level should show a steady vacuum reading between 14 in. Inspect vacuum lines for You can try different carb setups, timing, advances etc. On my scan tool, I could read 37 kpa. Cruising on flat level ground in OD at 55 I only see about 7-10 inches. Higher-than-normal vacuum at idle is a common clue to overly This is how vacuum advance works. ( 100kpa or 1000mbar being atmospheric pressure close to sea level ). Also, what should it idle at.