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  #1 (permalink)  
Old 02-28-2019, 06:29 AM
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Default Jet size

I have a 427 side oiler stroker w/2 4160 600 holley 4 bbl. I have stock heads, MSD ign comp ratio is 10-1 with a Crower cam (16331) lift 551/565,Lob center 108, ford roller racing rockers 7-1 ratio. I sent the carbs out for a complete rebuilt and restoration to be sure everything was correct. I'm running #70 jets on primary/secondary on both carbs, #25 squirter. my plugs are a little on the dark sooty side (not oily).The car runs very strong no harsh smell when at idle and no exhaust smoke. My question is #70 jets a little much for this set up? My gas milage is almost zero, but who cares.

I forgot to mention my exhaust tips are black sooty not oily just black carbon you can wipe off with your finger. The heads have been recently gone over, harden seats, valves, springs, guides, seals etc.

Last edited by classical glass; 04-01-2019 at 01:38 PM..
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  #2 (permalink)  
Old 02-28-2019, 04:05 PM
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Standard main jet for a list 1850 600 vac sec 4160 is a 66, so the carbs have been jetted up on the mains a fraction, where the PVCR should have been opened up if necessary.

The car needs to run up on a dyno to check the A/F ratios from idle to WOT.

Once the figures are established, the carbs are disassembled where necessary, and a few changes can be made in one hit.

Eg, idle rich, off idle rich, start of main lean etc.


Last edited by Gaz64; 02-28-2019 at 04:24 PM..
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Old 02-28-2019, 04:13 PM
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4160, is't that a vacuum secondary carb?

Never mind Gaz answered my question

Last edited by RET_COP; 02-28-2019 at 04:16 PM..
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