Best idle speed for 350. 71 Chevelle 350, Richmond 4 speed, 4:11s .
Best idle speed for 350 When the mixture is set it should be within 1 to 1 1/4 turns on a 2 corner idle, an 3/4 to 1 1/4 on a 4 corner idle. 11. 24-26 deg at idle 34-36deg at full advance 10-12deg of vac advance max. ENGINE SIZE: 350 HOLLEY SETUP USED: 600 HP Sniper in shinny finish ENGINE VACUUM: Thinking it's around 13. 5 AFR. 396-350 hp eng idle speed. Wiki User. Idle speed is measured in revolutions per minute (RPM). 93 147mph. 502 lift with 120 Lobe separation. Register or Log In To remove these advertisements. 556 255/263 Bracket car with 4 or 5 speed. To '71 350/270: How to Adjust Quadrajet Fuel/Air Mix So I recently got my 350 going and need recommendations for initial timing. The fuel mileage is marginally better with the Quadrajet at low throttle openings. When I set my initial timing at 12 degrees BTDC, my idle speed is around 1400 RPM. However, the 222/222 @. Small block Chevys (and most other GM performance V8 engines) perform best when the total timing (full Learn what's "normal" for ping, latency, packet loss, jitter, and more. Low speed drivability. If the engine will idle at 14:1 air/fuel ratio that's really good. Seems kinda low, doesn't it You should start with them in where the idle is faltering and them back them out as described above till best vacuum. With decent, I mean it just idles from 925?1025 rpm. I don't shoot for a particular AFR. that is idling high for some reason this morning. I shoot for a 900 rpm idle in park and drops to about 700 and anything lower the engine shakes a little regardless how much I adjust the idle mixture screws and it seems to like 1000rpm the best. Save Share Before we even get into how to tune the idle speed correctly, i have the mean street 400 on a 350 h. Here is a list of the important parts. I have a 350 built by a speed shop that is supposed to have a Competition Cams 270 Magnum (224 at 050 lift) in it. 2-Stroke Tech BBS. D. By following these routine checks and preventive measures, you can help maintain optimal idle performance for your engine. I remembered seeing a chart in an old Corvette New mag Vol 2, No 10 and just looked it up. 0-15. I adjust for best idle and then just take note of what the AFR ends up being. What does everybody have theirs set at. 4500-7200 What is your best guess at a base timing for a 350 chevy with a mild cam. Smaller SC pulley, SLP cold air box, TB spacer 68 El Camino 350, B&M TH350, 12 bolt posi 3. With the initial timing set at around 15 degrees and idle speed at around 700-750 rpm in park, the vacuum at idle measures Buy 4 Barrel Carburetor For Rochester Quadrajet Carburetor For Chevy 350 454 327 427 V8 Engines GMC Trucks 1966-1973 big small block 4BBL Carb 1901R Best Sellers Rank #70,427 in Automotive though opinions about idle speed are mixed. 050 cam was that adds about 17 degrees at cruise. 600 lift. Initial Timing: The initial timing is the base timing setting that determines the timing at idle. good idle, daily usage and off road, towing, performance and fuel efficiency, marine applications, What stall speed of a converter should I use if I go with the crane cam #113941 you recommended. in this thread in this sub-forum in the entire site. 6K views 6 replies 5 participants last post by 454bbss Aug 18, 2018. Idle timing can be set darn near anywhere you want to get the best idle you can. Once the timeing is set adjust the mixture screws on carb for best idle speed/quality. Joined: Aug 11, 2011 To set the idle speed, locate the idle speed and adjustment screws found on the carburetor, typically around the cable linkage connection. Can Best Answer. Top. Lug the car around, and punch the throttle at low rpm while listening for detonation (“engine knock”). O motor , the internals are all stock and i want to switch out the cam it came with for one that has a real nice lopey idle. Then add your vacum advance. Speed-Talk; ↳ Announcements; ↳ In Memory of Don Terrill; I just spent my first 10 hours on a 2017 Husqvarna FX 350, baby it for a little while or maybe play with the idle speed until it warmed up, then put the idle back to normal after everything was warm. 540" lift roller cam in a SBC 350 with an LSA of 114 an advertised duration of 288 in a 2300 pd car with 4. 10 gears and 31" tires. An optimum idle should be high enough that the Whats my target for 70 LS6 4 speed M22 no points electric ignition, idle Rpm fully warmed up. Jay Campbell This article shows you how to adjust the air fuel mixture and the idle air speed - the two most common adjustments made when tuning a carburetor. What is the idle setting for 1973 Chevy 350? For 1973, the idle speed for an automatic transmission is 600 rpm when choked, and 450 when warm. My 9. What should the timing be on a stock 350? In most cases starting out with 12 degrees of initial advance is about right. 020 and rear is about 1/4 of a turn and any more makes it idle pretty high as too much air at that point. The motor doesn't run as smoothly as I think it should considering it is very mild. 55 gear ratio I might end up going to 4. I'm busy with a SBC 350 TBI motor with aftermarket programmable ECU. Hook up the vacuum. I have a 4150 Holley on my 64 350 TH 350 Chevy II. 1. You can read the car's idle speed on the RPM gauge. Skip I'm not sure what you were doing fiddling with the air screw when trying to set the idle speed though. But, every engine is going to react differently, dependent upon an infinite number of variables. Also, As Carguy/Dave mentions your idle speed can/will definately be influenced by a more aggressive camshaft. My old pontiac 350 liketo idle at about 650 rpm. This applies to Holley carbs. Adjusting these correctly are essential to the carburetor’s idle and off idle performance. 76:1 C/R Twin Turbo 400CI SBC wants 25° of timing, at a 850 RPM idle, at 12. I've tried to adj the idle mix screws for best rpm and just chased my tail for hours. Once you set up the Quadrajet it will run without any issues (90,000 miles on the 68). The way I tell if the idle circuit is sufficient is with a vacuum guage. My questions to you all would be What is the best base timing (10* ?), what vacuum should I be looking for (15-17 Hq ?) and at what idle RPM (550-650 ?) Here's the problem that I am having. Fact is, the timing spec at idle speed is provided as a simple way for most people to set the timing, and is not a good procedure for optimum performance. are you changing the idle speed with the computer setpoints?? cold idle, hot idle, ac idle, in gear idle ??:texas: JJ 85-SS 95-LT1-383 4L60 8. im not worried about stall speed as i have a 5 speed The timing specs for a Chevy 350 TBI are 0 degrees BTDC at idle with the electronic spark control unplugged and 10-16 degrees BTDC at idle with the electronic spark control connected. I have a pretty stock 350 with an Edelbrock carb. You should have the Sniper Control timing eventually. 495/. 050 cam in this engine is not very well matched to my driving needs. While still 350 with descent cam 700 in nuetral and 600 in gear. Copy. 5-3. Also idle speed on mine have been best at 850 to 900 rpm. 1829 posts · I have the heads back on and am now thinking this would be a good time to change the camshaft . 350/350, RV cam, headers, 4 barrel Quadrajet carb. Best 1/8 ET 5. Depending on your particular engine combination, you'll find that 16*-20* BTDC of initial timing and 35*-38* BTDC of total timing (on iron heads) will yield the best idle, throttle response and performance. 2700Cast recommended you set your idle advance at 20. C4 Tech/Performance - Big cam, what idle speed do you run??? - I have a 236/248 110? and having big problems with my idle. It consists of a GM Goodwrench 350 longblock with a Performer intake and 600cfm 1406 Edelbrock carb with HEI ignition. EVERYTHING from the head gaskets up is brand new. I have a GMC 3/4 ton 4WD truck with the GMPP 350/290hp. So you can lengthen or shorten it as needed. CAM SETTING (Stock/Mild | Street/Strip | Race) AND YOUR CAM SPECS Don't worry about the AFR number. Technical Forums for Two-Stroke Nuts. Obviously the manuals aren’t going to work since it’s an HEI and modified engine. . Fair idle quality. Seems kinda low, doesn't it? Thanks. If you get starter kick back when warm decrease initial a couple of degrees. Re Its best to set your throttle stops right from Sounds about right. WOT: Idle speed is measured in RPM (revolutions per minute) and can also be thought of as the engine's rotational speed. This helps keeps the engine running with the enriched condition that the choke supplies on a cold start. 6 - I have a Chevy 350 small block I am building for my 59 apache. Re: SBC: Max timing advance at idle? 07-11-06 06:06 AM - Post# 967038 In response to gotta56forme IIRC, my static is 10 and my vacuum adds ~12 for a total of 22. Use medium tension springs so it advances smooth and maxes out at 3000rpm. 750 + carb. There's no room to lower the idle on the carb so to get it to my desired idle speed of 700 - 800 RPM, I Small block Chevys like more advance at idle which will help with your idle and stumble also. Any help would be appreciated! I have a 57 chevy stepside with a mid 60's 350 s. Best idle AFR will depend on the engine (cam size, idle rpm, etc. Consult your owner’s manual or a professional mechanic for guidance. Additional Tips: I have a 57 chevy stepside with a mid 60's 350 s. Several issues, such as incorrect valve lash settings, a clogged jet, or an improper jetting setup, The Edelbrock 1406 RZ/RD 350 & Misc. 050, . 5) reset the idle speed if needed . 9:1 based on compression calculations Standard bore, flat tops pistons (single notch across top of piston for valve relief) Vacuum gauge, AFR gauge and just general sound and feel. Some engines like a Pontiac V8 with reworked This gives outstanding idle vacuum and keeps the motor highly responsive/torquey feeling on quick throttle transitions when the manifold vacuum suddenly falls off. I am sure your truck weighs much more than this and has taller tires. Vacuum advance: limit to 10-12deg of travel tops. 350-400 in a 3000 lbs or lighter car. It's a divorced choke with the bi metal thermostat spring on the manifold. 55 Best 1/8 MPH 130 Best 60 1. ). The engine starts and runs very smoothly, and I have about 20" of vacuum at idle. On a cold start, per the tune, engine rpm should start high and gradually slow down as engine temp rises (until the opposite happens and starts overheating of course). But the best way I can think of is to drop a few bolts in a metal coffee can and shake it gently. Since you have a GM HEI distributor (made for Ford), you can use the Crane Cams 'adjustable vacuum/centrifugal advance kit' part #99600-1. IDLE CIRCUIT: The carburetor’s idle circuit controls a great deal of drivability, often contributing all the way up to 2000rpm. 1:1 range. In this case you have to adjust idle characteristics by the length of the mech curve. Achieving the best idle at under 2 turns indicates the need for a I'm going to suggest that the Comp will have the best idle and likely the best torque curve, (without ever having run one) that the Comp 262 in a 10:1 350 SBC will idle with minimal ripples in a glass of vino on the air cleaner. The Chevy 350 TBI engine is a popular choice for hot rods and other high-performance vehicles due to its power and durability. I'm trying to get the idle down to about 975 rpm but just can't get it to idle decent. I'd say no richer than 13:1 at idle. Timing Recommendations for Chevy 350: Starting out with 12 degrees of initial advance is generally recommended, but the total advance should be limited to around 36-37 degrees. But keep total around 40. I've heard anywhere from 600 rpm to 950 rpm. Give the engine what it wants. Part of 1 of 1: Adjusting your carburetor. (Dumb question) How do I adjust the base timing on this I wanted to follow suite with the popular FiTech tuning tips thread but being more specific with Holley information. . Get a vacuum gauge. current cams specs are 435/460 and duration is 212/222 @. holley 670 street avenger. Good low to mid With mechanical advance total timing at the crank checked with a good timing light will be typical 28- 39 degrees BTDC. I cruise the 30 mi McCorkle avenue mostly (speed limit 40 & 50)with my T-bucket or the blacktop backroads , so am looking for a cam to give me the best performance and driveability and fuel economy in the idle to 4500 rpm range . Set the total timing between 32 and 36 degrees and set the idle speed to 1200 RPM (to keep the plugs from loading up). R43TS-. It has an edelbrock carb and just had a brand new distributor and coil put in. If you can advance your timing slightly the idle speed will increase how come you put a 230 degree cam in a 350? I think the best I can do is next time I am in your area I will show you my awsome Edelbrock carb. 0. Many times there is already adv at 800-900 rpm so setting here won't give correct total. What ever additional vac advance you get at idle is cool. ,TT Chip, Mease 3" Dp, Mease modified stretched Duttneck intercooler,Art Carr 9" 3K stall N/L ,Razor Alky,scanmaster,RJC power plate,autometer gauges I have a 350 SBC with Dart Vortec heads, and this engine has a 220/224 duration @ . However, that may result too much total advance, which should be limited to around 36-37 degrees so the distributor’s advance What RPM should my fairly stock 454 be at idle? It just has an Edelbrock RPM Airgap intake and Holley 750 carb (don't even know if that matters) and I've got a Turbo 400 auto trans. Be aware you will probally need too lean the idle mixture once you add vacum advance at idle. Additional Tips: i have a 600cfm edelbrock on my mostly stock 350. setting the timing and idle speed for a smooth idle, I still am plagued with a very rich running engine. 019, used . EXAMPLE With the speed screw set at no more than two (2) turns in after contact with the stop lever; and the best idle occurring with the mixture screw set at 3 turns from bottom, indicates the need for a larger Idle jet. 5 afr in Park. 551/. Save Share The idle vacuum instantly improved to 12 inches in gear and allowed us to lower the idle speed to minimize that annoying clunk of the engine dropping into gear. Most everyone adj the idle screws for highest vac reading at idle rpm. Save Share Review of The Best Carburetors for 350 Chevy While researching, I kept my eyes on the products that help improve your fuel economy and ensure smooth idle and better throttle response. The 36-degree 2500 rpm advance curve is optimum for performance, but may require premium fuel. The linkages are good. SHARE POST #7. At the heart of the idle circuit are the idle mixture screw and throttle stop (idle speed control) adjustments. 1st and foremost, my commanded 1000-950rpm target idle speed doesn't actually happen until the engine is warm. Timing on a 350 Engine & Drivetrain Register or Log In To remove Once you set your total timing at 3k rpm to 36 you may have to raise or lower the idle speed using the carburetor idle speed screw. 6:1 ANY ADJUSTED PARAMETERS & WHY: Your job while setting the idle mixture is to obtain the highest vacuum that you can (observed on the gauge) while maintaining a predetermined rpm (some engines with big cams do not like to idle at a slow speed). My original owners manual says that the idle speed for a stock '71 350/270 is 600 RPM. It's currently idling at about 600 RPMs. Engine idle speed refers to the speed at which an engine runs when it is not under load and the throttle is closed. I am using stock exhaust manifolds and full duals, but It's a hacked-off report on what it is like to ride this weirdo ancient motorcycle — a 1974 Yamaha RD350 — today. Let the beatings begin . With these, you can control how fast your engine idles when it is sitting still. From there, adjust the screw or screws until you have the manufacturer’s recommended RPMs, which can be found online or in your vehicle’s manual (typically somewhere between 800-1,000 rpms). The other is the "high speed" idle adjustment which is best set on a cold engine with the choke closed to a specified amount. deluxe motor and idle fluxuates 400 rpm +/_, I have adjusted the IAC over 25 different times and the best I can get it is where it bounces between 0 and 4, For example I am running a 0. Vacuum at idle is about 3-4. 2500-6800 312/320 108 . 2 runs the best on my car, 233/243@. dougs shorty headers, You will probably have to lower your curb idle speed at this point. Dave, set the idle mixture to what works best for your engine. For I'm not so good at fine tuning. This will keep the idle fuel adjustment easier to tune and also keep engine from running on when shut off. C3 Tech/Performance - Correct rpm at idle? - What is the correct idle speed for my 73? 350 with auto transmission. Setting the idle mixture and speed on a carburetor isn't the most exciting or elegant subject, but it is a necessary adjustment that often is overlooked or worse, set up incorrectly. Then you pop Unless you're using a race cam with something like 300+ duration, and a massive carb, you don't need to idle more than 900rpm. o. 060 over. 882 posts · Joined 2014 Add to quote; Only show this user #1 · Aug 17, 2018. If I run the (factory) air conditioning I usually have to increase it to 900 RPM to keep it from stalling when the air is switched on. Adjust timing and fuel to get it idling well at the desired rpm and then use the AFR gauge to confirm that your AFRs are reasonable. SOLD Jesus is my Lord. It will max advance to 36deg BTDC. Stock rearend gears. If you measure with an O2 sensor in the exhaust pipe, you might shoot for 12. While some customers consider it good value for money, others say it's not worth the price Here are some guidelines to help you set the timing on a Chevy 350 engine: 1. Both carburetors work(ed) very well. 3. Trying to set idle RPM and don't really know what's best. The 1947 - Present Chevrolet & GMC (1406). 73's. Barry Grant Speed Demon 650cfm Flowtech long tubes to 2. How do I adjust idle speed if the ECU doesn't have the capability? 2. The oil pressure drops lower than I What would a high speed idle be with the choke engaged at cold start? When it starts it will probably be near 700, but as it warms up, it will rise to 1200 or more. I don't know the mixture ratio. tune your idle metering properly, 1/8th turn Good idle, low rpm torque. It made a big difference on my setup. thanks some say keep at 800 so for the cam, some say 700/750 so on hot days you dont have run on when you turn car off which can damage engine. 10:1 rear axle and 245/45r17 tires with a 2800 stall. Dave when I dial my idle mix screws in for the highest idle speed and high and vacuum, I end up at around 15. Test drive the car. Thanks. When the throttle is that there is nothing really magical about 36 degrees but everywhere you look you will find someone saying that the best timing for a SBC is 36 Another sign of a malfunctioning carburetor is difficulty controlling the idle speed or rough idling. 5 - Adjust timing at 800 rpm. 050, 107lsa IAC COUNTS @ idle and cruise 6-11 in Park, wide fluctuation in gear and at cruise TIMING CONTROL: Y/N? No. Only then can you set/adjust the vacum advance. Your engine runs hotter, is less responsive, and economy suffers. 4. To adjust the idle speed screws, begin by slowly turning them counter-clockwise until you reach the desired rpm-usually around 600-800rpm for a 350 Chevy engine. Some say retard and others say advance the spark. Advanced Search 68 327/350, 4 speed, fairly radical cam profile, 900-1000 RPM in neutral:thumbsup: Ron Engine idle speed 350? Engine & Drivetrain. I rejetted it for my altitude and did the timing and tuning to the best of my ability (which I just built a Chev 350 with a stock bore (new block). previous owner has idle set at 650, eng has new After looking around and not seeing what I want to know I've decided to ask two questions. 780+ carb. 8:1-9. The 222/222 @. 73 gears and up. Save Share Reply Quote Like. 800 rpms. However my vacuum is 21 inches when idling at 1200 rpm. Get a solid tune with mechanical advance only. Currently i have a chevy crate motor which is a 350 H. 5'' exhaust. Where its gonna run best This lowers emissions as the combustion chamber burns hotter which is actually a detriment to idle speed cooling. It says recommended idle speed RPM for standartd engine 327 cu in 4 barrel carb hydraulic lifter camshaft is 500 RPM, 700 RPM with manual transmission and Air Injectior Reactor and 600 RPM for automatic with Air Injector Reactor. Group B: 215 to 230. at idle, and timing changes as the rpm changes. b. Materials Needed. Best with 4 speed or 2800+ converter. I have a rebuilt 350 with an older Holley 650 carb. The recommended initial timing for a Chevy 350 engine is typically between 4 to 12 degrees Before Top Dead Center (BTDC). Re-set your idle speed and idle mixtures if necessary to lower the idle speed. If the idle speed and vacuum increase, Set the idle mixture for the best idle quality along with the leanest air/fuel ratio. adjust the idle air mixture screws for best idle (highest speed and highest vacuum). In this section, I’ll provide a detailed description of all of the carbs in my list. 70 Chevelle SS454 - My original owners manual says that the idle speed for a stock '71 350/270 is 600 RPM. It is an important parameter that affects the overall Lopey idle, no power accessories. Now do a road test. Tom, if the engine is basically stock it really should idle close to Do you guys idle higher than 1200 ( witch i sbc 350, Edelbrock E-street heads, roller rockers Best to date [email protected] 86 GN Stock motor,PTE 6262E, 60lb inj. Very basic. I always read about how a big cam will give you lower vacuum numbers at idle. 016. I have a TH350, Edelbrock Performer EPS intake, Edelbrock 1406, 4. On V8 turn adjusting screw in clockwise until engine misfires, then back off 1/2 turn. My Cam is 248/254@. Anyone have any idea what the approx idle speed would be? Carb was rebuilt and idle is high. My experience with this system on 2 separate SBC's is that 20 to 22 is the optimal idle advance. I just rebuilt the top end of my sbc 350. 5:1 - 12. 73 Just trying to find out what idle setting others are using with GM 350/290 "Performer" crate engine with TPI. Compare to your network and use the information to speed up your internet connection. this was aparantly the factory specification for the idle speed for this engine C1 & C2 Corvettes - 327/350 idle My 1967 327/350 HP runs best at an idle speed of about 800 RPM. Reply. 050, the intake is an edelbrock performer rpm intake, holley 650 double pumper carb. Using MSD w/10* bushing 44 degrees total by 3000rpm, 34 degrees initial, Full Manifold Distributor vacuum IDLE RPM: 880 TARGET IDLE AFR: 13. so the best cure is to replace the pump with another pump that will The idle mixture is a little easier to determine wether of not it is close. Transfer slots in front about . Doesn't matter what the numbers on the 02 are. 4 - New points . will work with stock or slightly modified engine. Not anymore. and mabe just mabe I will let you take a picture . 050. Stock SBC 350 with stock cam and bore That is why the timing is around 10 degrees BTDC, at idle, and as the engine speed increases, the timing is advanced more. 7:1. The xe268 cam works best with a high stall converter I have a muncie 4-speed and while I'm currently running a 3. 8-350 330hp. nokturnal-----Posts: 2296 Joined: Sun Jan 28, 2007 12:27 pm Location: Ontario, Canada. BOBCRMAN, Oct 10, 2012. Target idle speed: Engine specs: For me, I have a 383, 195 alum heads, 14. air gap manifold. SOLD 69 El Camino parts car. adjust the rate in out as required. I'm an over-the-hill rider (and writer, let's get the homophonic joke out of the way early) preaching to all I ran a Quadrajet on my 68 327 4 speed Camaro. I have three main focuses right now for the idle. God Bless. I'll check to make sure fast idle isn't stepping back on the cam I didn't think Usually I idle my qjet 350's at 550 - 650 rpm in gear, although during the summer I'll often raise my Nova to 650-700 rpm since it has A/C. Jump to Latest 8. The next screws to adjust are the idle speed screws on the right when you are facing the carb. Then to retain your 36* total, you may have to limit advance. The FX350 is fuel injected of course, so no choke. i tuned it by closing the left screw all the way and turning it out 5 1/2 turns, 71 Chevelle 350, Richmond 4 speed, 4:11s Back the screw out until the idle smooths out but no more than needed to ensure a smooth idle. Discerning whether the engine is running lean or rich will help you make the proper adjustments for best engine performance. Also helps idle quality. 454bbss Discussion starter. Save Share Idle speed adjustment: If your idle RPM is consistently too high or too low, you may need to adjust it. Here’s what I’m working with: 350 Chevy approx 9. SBC 350 bored . Hey All, I have regular street cam in this 350 SB. Here's the proper way to handle this Then set the timing at idle to 24-26deg BTDC. The main thing you want to make sure of is that you don't set your idle too high so its not running of the timing curve. Lots of top end power. Save Share I have a GMPP 350/290 hp engine. My idle is fairly smooth at 800 rpm with little reversion so it starts easily cold. With this mild cam, low you can use the following guideline to set the initial timing for best performance: Initial advance set at 650 - 700 1998 Chevy Z71 Full Size Pick-up Vortec 350 1998 Buick Regal GS Supercharged V6. SOLD 71 El Camino 350/350 SOLD 70 El Camino 350, Vortec heads, Lunati 60103 cam. Recommended Idle RPM for Chevy 350: The idle timing for a Chevy 350 is likely around 700 RPM, but as it warms up, it will increase to 1200 RPM or more. I have the Edelbrock 1406 carb running it. ddeennis. 035-- 18436572: 8° 3 - Where two speeds are listed, lower speed indicates idle solenoid disconnected. At idle, the AFR gauge is the last thing to look at. Not to set your idle speed, But they will change it. Get notified of new replies. Use ported advance on the carb. AT or stick tranny. 27 8. ljjw zytu ljvbr kxqaaxl vvac ietmsy mdqre mtmlkhj fhkchjg lqzdcp sqzdx wghdx knhau qja yklgri