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Tunning a Holley With a wideband

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Old Nov 5, 2003 | 11:42 PM
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AustinT's Avatar
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From: Cannonville,Ut,Usa
Tunning a Holley With a wideband

Hi,
Just bought A Innovate motorsports wideband Works great!

Today I installed the sensor just after the y, where the exhaust goes into one pipe. At idle The A/f ratio is 12.5 . When the powervalve comes in it jumps to 11 and at full throttle it runs at 10.5 Would the power come up if I Leaned it out a little? Dont I want to cruise at 15/1 and be at 12.5/1 at full throttle? Also I dont want to run the end cylinders lean. How much leaner do they run than the other cylinders? Would I be Ok at setting my crusing afr at 15/1 since it would not be under load?

750 holley VS
73 primary and secondary jets
zz430 crate motor
Thanks
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Old Nov 6, 2003 | 07:04 PM
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305sbc's Avatar
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From: Fairview Heights Illinois
Car: 1986 Irocz
Engine: 305 TPI
Transmission: 700R4
Axle/Gears: 3.25:1
Re: Tunning a Holley With a wideband

Originally posted by AustinT
Hi,
Just bought A Innovate motorsports wideband Works great!

Today I installed the sensor just after the y, where the exhaust goes into one pipe. At idle The A/f ratio is 12.5 . When the powervalve comes in it jumps to 11 and at full throttle it runs at 10.5 Would the power come up if I Leaned it out a little? Dont I want to cruise at 15/1 and be at 12.5/1 at full throttle? Also I dont want to run the end cylinders lean. How much leaner do they run than the other cylinders? Would I be Ok at setting my crusing afr at 15/1 since it would not be under load?

750 holley VS
73 primary and secondary jets
zz430 crate motor
Thanks
Yes if you are at 10.5 then there is much power to be gained.
15:1 and even leaner is just fine for idle and cruise. You will not damage an engine by running lean unless it's under a heavy load like WOT. 12.5 is a good place to start with the WOT and then just keep an eye on the plugs and an ear on the engine as you go leaner than that.
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Old Nov 6, 2003 | 08:07 PM
  #3  
ronterry's Avatar
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From: Elizabeth, Colorado
Car: '94 Corvette
Engine: LT1
Transmission: 4L60E
Nice little tool 'AustinT' how much?

I've been using a regular O2, and it's giving me a very basic tuning window. The only real thing I got out of mine was maybe a lean spot here & there. Other then that I've been working on getting it close with plug readings.
What kills me, is that after getting it close I have to go buy a ProForm body, and I get to start over again
Man I need one of those, so I can pursue other projects!!!

BTW: Agreed 12.0-12.5 is what I would aim for at WOT. I wouldn't try to nail it unless it's race weekend, because temp & pressure is going to screw with it a little.

Ron
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Old Nov 6, 2003 | 11:08 PM
  #4  
AustinT's Avatar
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From: Cannonville,Ut,Usa
Hi

If you are looking to get a wideband go to this forum, A second group purchase is taking place.
https://www.thirdgen.org/techbb2/sho...78#post1509878
Thanks for your reply
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Old Nov 7, 2003 | 06:06 PM
  #5  
Catalingus's Avatar
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From: Norfolk, VA
Car: '59 Catalina 4 door
Engine: Cheby 350
Transmission: TH350
I may be dumb-founded, but if your carburator runs perfect under normal conditions and gets lean at WOT, shouldn't you just up the secondary jets? You could also get another front metering block and put in on the rear. You'll have 2 power valves, while having same jets as before.
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Old Nov 9, 2003 | 05:03 PM
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Car: Turbo Buick
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upper 12s is a good place to aim, 12.5 to be safe no matter what but 12.0 will definately be too rich unless you are running forced induction or have some other strange circumstances like alot of compression

peak torque should be richer than peak hp in the rpm range too, some cars like a bit above 13 for peak hp if they are real efficient.

I dont think you can get that kind of precision out of your average carburetor though anyways. Ive been trying, its alot of work though you can see my WB datalogs on my other posts on this board
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