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Weber tuning issue A14


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#21 distributorguy

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Posted 29 January 2018 - 10:21 AM

You still need to address the float settings.  They get bent up in shipping, despite what Pierce says.  Float settings affect fuel mixture at ALL rpms  Idle mixture also affects fuel mixture at all rpms, just not in a great amount.  We use the idle jet to bolster or shave down the peak rpm fuel mixture in our race truck, because it ALWAYS flows fuel at any rpm.  It has to be properly set before you change jets.  But first, float height and drop are key.  



#22 Dirtyowlnumber4

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Posted 29 January 2018 - 12:58 PM

I think I am going to get an electronic distributor in it before I tune it anymore so I know the spark is strong enough, then I will look into high altitude jets. The shop here probably has a little air fuel gauge they could use on it. The spark plugs are black, but I've got the screw quite lean so I dunno.

 

Seems like the return on the distributor is fine, and the points are fine.

 

I've got the carb apart now I'll check out the float height.



#23 Dirtyowlnumber4

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Posted 29 January 2018 - 01:07 PM

All right I set the float height it was about a quarter of an inch off.



#24 Stoffregen Motorsports

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Posted 30 January 2018 - 09:55 AM

That will make a difference.



#25 banzai510(hainz)

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Posted 30 January 2018 - 12:49 PM

That's great you got it fixed. Never seen that issue much on here. I learned somethng new


Throw on some Weber sidedrafts, Rising Sun hood.... call it good

#26 DIY 1985

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Posted 31 January 2018 - 07:01 PM

How much will an air horn increase air at idle?  I'd like to increase the idle speed, but my idle speed screw is just beyond maxed out.



#27 datzenmike

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Posted 31 January 2018 - 07:05 PM

None at all. It may help extreme high revs.

 

Idle speed screw should be almost closed. Maybe you have something else.


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#28 DIY 1985

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Posted 01 February 2018 - 07:39 AM

My bad, I meant that it is at 1.5 turns in and at low rmp (no tach). I'm considering a .040" hole drilled into the throttle butterfly(s) opposite of the progression holes. I put a .008" feeler under the secondary throttle stop and it appears to open the second idle circuit (richer). When I used a .005" feeler it appears to do nothing.

#29 Stoffregen Motorsports

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Posted 01 February 2018 - 09:50 AM

The only air horn I know of that's available for a DGV is super expensive and will only fit inside a very tall air cleaner. You need to be sure to use a filter that is tall enough or you will disrupt the air coming into the carb. Preferably a foam filter from someone like ITG so it can suck air from the top as well as the sides.

 

Super expensive setup and probably not worth the effort.

 

We did play with different types of DGV air cleaners on the dyno once, and using an aluminum round air cleaner adapter, we found that if you raise the adapter closer to the opening of the carb, you can increase HP. Not by much, but it was measurable.