VG30e, Carb and Tuning Questions?

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F8d2Blk
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VG30e, Carb and Tuning Questions?

Post by F8d2Blk » 15 Apr 2009 13:25

Holley Carb, AEM UEGO Questions?

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I am trying to find the best a/f ratio for my carburetor. I think most know my setup. It is a VG30e with 2 barrell Holley Carb in my 510. I don't know the jet size as this will probably be what will fix all by swapping out jets but I am trying to just get this thing running safe enough for autox the next few weekends.

Alright this is kind of what is going on right now when I am at idle it is around
11.0. Which is rich, when I get on it full throttle it goes up to 13 range. And leans out some. On holley carbs you can't really adjust air/ fuel mixture at full throttle. You can only adjust at idle essentially.

Questions:
Would you advance or retard the timing to get the fuel to burn better?

It seems as if my setup is back asswards because I know the jets are to big, I am really getting around 12 mpg.
So I know I need smaller jets but essentially what should the car be reading
at idle, at partial throttle and full throttle?

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defdes
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Re: VG30e, Carb and Tuning Questions?

Post by defdes » 15 Apr 2009 14:13

My A/F always runs from around 13+ at idle to 13.8.

510Martinez
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Re: VG30e, Carb and Tuning Questions?

Post by 510Martinez » 15 Apr 2009 18:27

Idle should be close to 14. General running in the mid 13 range. WOT should not be lower than 12, preferably around 13 also. During steady cruising, Holleys have air bleeds that lean it out a little. You would improve both your mileage and your power by leaning out the jetting a little, typically starting 2 sizes smaller.

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F8d2Blk
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Re: VG30e, Carb and Tuning Questions?

Post by F8d2Blk » 16 Apr 2009 05:15

What size jets are you guys running?

510Martinez
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Re: VG30e, Carb and Tuning Questions?

Post by 510Martinez » 16 Apr 2009 09:14

The Holley is in my plow truck and even one carb to another in the same vehicle may not apply here. You'd have to open yours and see which one you have.

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F8d2Blk
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Re: VG30e, Carb and Tuning Questions?

Post by F8d2Blk » 16 Apr 2009 10:24

I know that is probably true but there are a bunch of people that are running the vg30e with the holley 500 2 barrell and the same engine that I have. So it should be a close match. Any help would be appreciated.

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okayfine
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Re: VG30e, Carb and Tuning Questions?

Post by okayfine » 16 Apr 2009 12:04

F8d2Blk wrote:I know that is probably true but there are a bunch of people that are running the vg30e with the holley 500 2 barrell and the same engine that I have. So it should be a close match. Any help would be appreciated.
If so, you shouldn't have any problem tracking them down and asking them. Are there really more than a handful of carbed VGs in 510s, though? I'm fairly certain there aren't a "bunch."

Shouldn't you just be asking Dave at Experimental Engineering? Go to the source. Holley will also likely provide you a baseline setting if you supply them engine specs. You could also research OE applications of the carb and find a 3L V6...
Because when you spend a silly amount of money on a silly, trivial thing that will help you not one jot, you are demonstrating that you have a soul and a heart and that you are the sort of person who has no time for Which? magazine. – Jeremy Clarkson

510Martinez
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Re: VG30e, Carb and Tuning Questions?

Post by 510Martinez » 16 Apr 2009 16:41

It isn't that hard and he shouldn't need anyone's numbers. Just open the thing up, unscrew the jet(s), go to a local store with jet and buy them smaller. Reassemble in reverse order with a new gasket.

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defdes
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Re: VG30e, Carb and Tuning Questions?

Post by defdes » 16 Apr 2009 16:45

It's nice to have the "established" base line just as a jumping off point.

510Martinez
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Re: VG30e, Carb and Tuning Questions?

Post by 510Martinez » 16 Apr 2009 16:57

defdes wrote:It's nice to have the "established" base line just as a jumping off point.
Of course more info is nicer, but that applies more to someone without an O2 sensor. He has an A/F already for his own baseline and will be able to see the changes immediately. There'll be no need to run WOT, shut off, and read plugs, etc. I love this modern era. It was a PITA in my younger days.

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defdes
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Re: VG30e, Carb and Tuning Questions?

Post by defdes » 16 Apr 2009 17:01

Oooh....didn't know about the AF.... then yeah, what are you waiting for?

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F8d2Blk
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Re: VG30e, Carb and Tuning Questions?

Post by F8d2Blk » 17 Apr 2009 06:13

Thanks for the info. I am learning more about these things everyday. I have tried to contact the folks at vg30 before and they never responded so I just didn't bother them about this one. I will report back my findings!

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