Author Topic: 17057231 jet/rod combo from the factory  (Read 446 times)

Offline Cadman-iac

  • Carb lover
  • ***
  • Posts: 77
17057231 jet/rod combo from the factory
« on: February 09, 2025, 11:52:06 AM »
  Trying to verify if this has the correct parts in it. The jets in it now are 73's and it's got 43B rods and I think they have been changed at some point.

 Thanks

Offline Kenth

  • Jet Head
  • ****
  • Posts: 497
Re: 17057231 jet/rod combo from the factory
« Reply #1 on: February 09, 2025, 01:03:49 PM »
Should have #70 jets and 48P pri rods. Sec rods stamped DS.

43B rods for 1974 or earlier 4M Q-jets are longer than 1975 M4 Q-jet rods.

Offline Cadman-iac

  • Carb lover
  • ***
  • Posts: 77
Re: 17057231 jet/rod combo from the factory
« Reply #2 on: February 09, 2025, 01:22:16 PM »
  Thank you, I thought the rods were too long after measuring them and checking Cliff's book. I appreciate your help Kenth.

Offline GSP7

  • Carb lover
  • ***
  • Posts: 73
Re: 17057231 jet/rod combo from the factory
« Reply #3 on: February 09, 2025, 04:28:52 PM »
Should have #70 jets and 48P pri rods. Sec rods stamped DS.

43B rods for 1974 or earlier 4M Q-jets are longer than 1975 M4 Q-jet rods.

Kenth,
 '75 and newer are .036" tip and 74 and older are .026" tip, is that correct year range about tip size?


.,
Idaho

Offline Kenth

  • Jet Head
  • ****
  • Posts: 497
Re: 17057231 jet/rod combo from the factory
« Reply #4 on: February 10, 2025, 01:22:15 AM »
Kenth,
 '75 and newer are .036" tip and 74 and older are .026" tip, is that correct year range about tip size?


.,

Only 1975 and later M4 primary rods with D, M and S suffix uses .036" power tip. All others have .026" power tip.

Offline Cliff Ruggles

  • Administrator
  • Qjet Hero
  • *****
  • Posts: 5476
Re: 17057231 jet/rod combo from the factory
« Reply #5 on: February 14, 2025, 03:57:18 AM »
For the record I sell full taper .036" rods to replace the "M" series on the later carburetors.  They taper from .050" to .036" and provide a wider range of adjustment via the APT system than the factory rods.

I also sell tapered .026" tip rods for the later carburetors to replace the later "stepped" "K" and "P" rods. 

"K" rods for example are pretty much useless in one of these builds as they only taper .005" on the entire upper section.  If you are trying to use the APT feature you will have a very narrow range of adjustment, and most "K" series rods are too big anyhow for effective tuning in the carbs they showed up in......