IAC modifications

[John Zarli]

>   Hope that better explains it.  Bruce
Well, not exactly.
Are you sure this is caused by IAC movement? 

I'm not clear on the sizing goal of your modified pintles.  What might I
expect if I fit the 10mm small TBI into the BB TBI, which uses a 12 mm
pintle?  Are we looking for less air change for a given ECM command or
more, quicker response?

I know how to seat the pintle, unplug the IAC & set minimum hot idle.
I am running a ZZ3 cam in a 355 truck engine. I have 3 sizes of TBI to
play with...a 4.3 V6, a HD 350 truck TBI, (same bore size) & a BBC TBI,
also from a big truck(2" bores).  I have been swapping the
regulator/injector "head" onto the BB TBI. The BB injectors ran rich, so
I have dropped back to the 350 size, but I am still getting a bit of
idle surge.  

The regulator portion of the aforementioned heads has:
18 on the V6 TBI
19 on the 350 HD emmis. truck (orange/blk inj)
25 on the BB TBI
 Is this some sort of sizing code, perhaps in metric?
Are all the fuel regulators pretty much the same pressure, save for
production/age variation?  Is there an advantage to further disassembly
& swap just the injectors?

I'd also like to impose on you for help in IDing the BB injectors.
I can make out a bit of red color. The numbers on them appear to be 
6285 GM
5235231 ACR

Thanks in advance for happening along at the right time.....If you want
to collaborate on a book, let me know...I'll write the first half....all
questions!!! (vbg)