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Old 04-11-2020, 04:38 PM
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Gaz64 Gaz64 is offline
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Join Date: May 2008
Location: Brisbane, QLD
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Quote:
Originally Posted by AC Ventura2 View Post
Hi Gary. Had to re register as AC Ventura2 to enable sign in.

Thanks for the carb info. I will check under load vacuum, by taping the gauge to the screen, but can’t drive the car as yet due to severe lockdown here. . In the meantime I’ve ordered a 4.5 and 8.5PV and a selection of primary jets no’s between 70 and 60. As they at low cost, I’m prepared to take a chance on this.
If by mixture screws you mean the four corner idles, they are all about 5/8 of a turn out from bottom. This is where I found the max vac. Any further in and it drops again.

If you mean the
I think you need some help from some exhaust gas analysis.
A wideband O2 gauge is helpful. I use a datalogger, which logs tps, map, O2, rpm.
Your mixture screws at 5/8 are close, but for me I would like to see them at 3/4 to 1 turn.
If they need to be at 5/8, the IFRs are a fraction big for your engine.

And now with lockdown happening, tuning a cobra on a roadtest is just not going to happen.

And if your "richness" is idle/low speed related, replacing main jets progressively leaner from 72 to down into possibly early 60s will not solve your issue.

Gary
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Gary

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Last edited by Gaz64; 04-11-2020 at 04:51 PM..
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