Author Topic: How do I correctly ID a Real RAIII RAIV airhorn  (Read 198 times)

Offline firebird400

  • Garage guy
  • **
  • Posts: 36
How do I correctly ID a Real RAIII RAIV airhorn
« on: August 03, 2019, 08:13:41 PM »
How do I correctly ID a Real RAIII RAIV airhorn compared to the basic grocery getter airhorn that seems to be the typical pieces on most carbs?
I can not locate any information on the internet how to get a real good image of the specific ID characteristics of them.
As far as stamping information numbers, certain markings, Holes or and unique air passages, S/N or P/N on them.
I have a

Offline Cliff Ruggles

  • Global Moderator
  • Qjet Hero
  • *****
  • Posts: 4140
Re: How do I correctly ID a Real RAIII RAIV airhorn
« Reply #1 on: August 04, 2019, 08:38:15 AM »
They will have a deep recess around the accl pump to accept the rubber boot and retainer starting sometime in the 1968 model year run.

Many non Ram-Air tops will be flat in that area, or much shallower and narrower recess.  Only a real Ram Air top will accept the boot and retainer without modification.

They also lack the primary POE system found on most of the non Ram-Air Pontiac carbs used in 1969 and 1970, so it's easy to spot a 1969-70 non Ram Air top.......Cliff



Offline firebird400

  • Garage guy
  • **
  • Posts: 36
Re: How do I correctly ID a Real RAIII RAIV airhorn
« Reply #2 on: August 04, 2019, 09:44:34 AM »
This seems like the one I have w the deep recess.
Perhaps I can send image sp you can give opinion on it.
I have the 69 Firebird RAIII W 400 HO engine.
And I ordered parts to mod my current non RA airhorn unit Q-jet).
So Is there a reasonable cause to put this RA airhorn on my 7029263 body while doing this mod as to possible gain performance?
It is currently on a 29273 full carb so not sure mixing it is the best choice.
Thx
« Last Edit: August 04, 2019, 09:54:32 AM by firebird400 »

Offline Cliff Ruggles

  • Global Moderator
  • Qjet Hero
  • *****
  • Posts: 4140
Re: How do I correctly ID a Real RAIII RAIV airhorn
« Reply #3 on: August 07, 2019, 03:04:17 AM »
Many non-RA tops will be recessed, but only a real RA top will be machined large enough to hold the rubber boot and retaining ring.  They are very rare tops.

I would NOT recommend mixing and matching parts, lots of reasons and there is no real performance advantage in doing so......Cliff

Offline firebird400

  • Garage guy
  • **
  • Posts: 36
Re: How do I correctly ID a Real RAIII RAIV airhorn
« Reply #4 on: August 07, 2019, 11:47:53 AM »
That

Offline 4ever18

  • Carb lover
  • ***
  • Posts: 67
Re: How do I correctly ID a Real RAIII RAIV airhorn
« Reply #5 on: August 09, 2019, 06:04:37 AM »
What is the casting number on the airhorn?

Offline firebird400

  • Garage guy
  • **
  • Posts: 36
Re: How do I correctly ID a Real RAIII RAIV airhorn
« Reply #6 on: August 12, 2019, 12:43:15 PM »
Being unfamiliar with it , let me know what location it

Offline 4ever18

  • Carb lover
  • ***
  • Posts: 67
Re: How do I correctly ID a Real RAIII RAIV airhorn
« Reply #7 on: August 13, 2019, 04:12:49 AM »
usually on front corner, passenger side of air horn.  May be on top side of AH or the bottom side.  Very small number, cast in a circle.  Will be about 1/4" in diameter and start with 70xxxxx.