SBC TPI manifold questions

[John S Gwynne]

   In message <960131081142_210770196 at mail06.mail.aol.com> , you write:
 
|   > Manifold:  89 Camaro TPI 305 w/ cold start injector
| 
|    Check the year, 89 Camaro's did not use the cold start injector.

ok... underside of plenum shows a casting date of Sept 87. Maybe it's
an 88?

<delete>

|     Are you going to use a MAP sensor?  Do you have your VE table yet?

Yes, MAP. Any VE date would be helpful if that's an offer :).

|   > Q) How did GM originally route the radiator bypass hoses?  One through
|   >    the throttle body then back to the block and a second to the heater?
| 
|     The large nipple on the front of the throttle body is for the incoming
|     hot water out of the manifold.  The throttle body exit did go to a
|     switch that was controlled by the HVAC system.  Normally this would go
|     to the heater core, but the heater core is shut off during max A/C, and
|     the the switch keeps the throttle body warm at all times.

On the base plate there are three holes into the coolant passage. One
still has a coolant temperature sensor (CTS), another a bypass hose to
the throttle body, and the third is empty. What originally attached
to this last location?

Throttle body questions:

Q) I would guess the top hose connection on the right side is a for 
the charcoal canister (just filtered fresh air). Correct?

Q) The second one down on the right looks like a "typical" vacuum port.
Sound about right?

Q) Now the tough one... there is a port vacuum signal near the left
throttle plate that works its way down to the bottom left of the
throttle body just behind the coolant passage. I have a hole here with
no hose barb or anything. I assume something use to attach here; what?

Thanks for the help.

                                       John S Gwynne
                                          Gwynne.1 at osu.edu
_______________________________________________________________________________
               T h e   O h i o - S t a t e   U n i v e r s i t y
    ElectroScience Laboratory, 1320 Kinnear Road, Columbus, Ohio 43212, USA
                Telephone: (614) 292-7981 * Fax: (614) 292-7297
-------------------------------------------------------------------------------