Carburetor Heat Shield

**Dicky** · #1 05-14-2014, 07:28 PM

Was there ever a performance engine on any model of
Chevrolet that got the Heat Shield from the factory???
Were they all over the parts counter???

Thanks, Dicky [img]<<GRAEMLIN_URL>>/flag.gif[/img]

**Mr70** · #2 05-14-2014, 07:33 PM

They weren't only available OTC.
It started out as an RPO on 1970 vehicles sold brand new in the state of Calif.,parts of Nevada and a few other low lying areas in the southwest equipped with the GM regular production option <span style="font-weight: bold">NA-9</span>....aka EEC~(Evaporative Emission Control)..aka Charcoal Canister.

This was not part of the A.I.R. SMOG equipment as some say.

**JRSully** · #3 05-14-2014, 11:31 PM

They do work great if you have a 70 L78 or LS6 with the 569 (flat) intake, helps keeps the hot intake from boiling the fuel in the Holley fuel bowls

**70 Forest Green Zee** · #4 05-19-2014, 02:53 PM

Dicky.....not sure of other year Camaros but the 1970 Z28 with Calf emissions RPO NA9 came from the factory with a unique heat shield that was very different than the one you have pictured. I'll post a pic of one below.

**SS427** · #5 05-19-2014, 06:44 PM

What it looks like installed complete with NA9 system.

**Dicky** · #6 05-19-2014, 11:27 PM

Thank you Randy & Rick.
That is an odd looking shield. So it is my understanding that
it did not matter where the car was built (NOR or LOS) it
depended on where the car (70 Camaro) was being shipped to, (Calif.)

I hope my car will accept the 3969835.(70 LT-1)

Dicky [img]<<GRAEMLIN_URL>>/flag.gif[/img]

**Mr70** · #7 05-20-2014, 12:45 AM

That's right.The deciding factor was what state/region the vehicle was going to be bought brand new in,i.e.(Calif.)
If that 1970 vehicle was assembled in LOS or NOR,and ordered by a waiting dealer in Calif.then it was assembled w/NA-9 @ the factory and would appear on it's buildsheet.
If the same vehicle was assembled in LOS or NOR,and ordered by a waiting dealer in Chicago,then it was not assembled w/NA-9 at all....but if that dealer in Chicago received it,and then did a dealer trade with a dealer in Calif.,then that Calif. dealer had to install NA-9 on it in it's service bay before it could sell it to it's buyer in Calif.
That's why many nickname NA-9,California Emissions.

**70 Forest Green Zee** · #8 05-20-2014, 01:07 AM

Rick....I personally doubt that any Camaros were dealer traded from the Midwest to Calf for sale....it would be quite a job installing NA9 at the dealership due to the fact it would require a new gas tank, and all new lines. The NA9 fuel tank was a non vented tank and they ran a line from the tank under the car all the way up front to the charcoal canister for venting. It would also require a new carb,a Holey #4489 which was specific to NA9 cars only,and the the special heat shield. It would make much more sense to find one in Calf to trade, or have one built out there in Van Nuys.

**Mr70** · #9 05-20-2014, 01:34 AM

I agree.
The latter was just a hypothetical example.

JohnZ · #10 06-04-2014, 01:09 AM

One of my IROC Z/28's (when I had them as company cars) developed a nasty fuel percolation problem, and there was a TSB on it to add that heat shield and a bunch of pieces from the California NA9 package to fix it. Took the dealer a couple of days to install everything, and it worked. Car was stolen the following Saturday from the Exec garage in broad daylight. [img]<<GRAEMLIN_URL>>/mad.gif[/img]

[img]<<GRAEMLIN_URL>>/beers.gif[/img]