Lower Air Channels 356B & 356C

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Brett Johnson
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Lower Air Channels 356B & 356C

#1 Post by Brett Johnson » Sun May 19, 2019 12:30 pm

According to the T 5 356B parts manuals, a different lower air channel (flapper box) with a 616 part number was first used on Super 90 engines. I'm assuming this is the one with the two exhaust flaps (back & bottom) in addition to the one at the front for heat to the interior. It isn't illustrated in any parts manual. The 546 part number one used on T 5 Super and Normal engines, which has only one exhaust flap at the back, dated to the 356A introduction, when carb heaters first appeared.

The T 6 book says to use the Super 90 components on the Super -- does not say to do this on Normals.

So -- was the dual flapper Super 90 lower air channel first used on the Super (S) at the T 6 change (or some time prior?) and then only on Supers?

The 356C book says to go back and look at the T 5 book.

So -- was the dual flapper Super 90 one on all 356Cs or just 356 SC engines?

If anyone collects Service Bulletins, perhaps these changes are mentioned with dates and/or engine numbers?
Brett Johnson

Dick Weiss
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Re: Lower Air Channels 356B & 356C

#2 Post by Dick Weiss » Mon May 20, 2019 10:59 am

Hi Brett,

We had our regular "Bull Session" event yesterday and a friend happened to be there who has a somewhat complete collection of his dad's license plates stored in a box--including some right after WWII.
So, I tried to ask if he has some of the years you were asking about last week and he sent a photo which I could forward to you if you give me your Email address (I thought I had it, but 'not').

Also, I tried to find when the double flap lower air guides became available after the S90 had them for the 1960 series; I think the later "flapper boxes' included some (maybe not all?) of the Normals in 1962 series.
Looking thru the service bulletins, it's not listed when they were changed; The single 'flapper" is still listed in the BT5 parts book and not in the supplement BT6 book (At least in my refs.)

Dick

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Al Zim
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Re: Lower Air Channels 356B & 356C

#3 Post by Al Zim » Tue May 21, 2019 9:28 am

Dick, you should remember this from the early 60's when Sports Car Body Shot and Service was where you hung out. A.C. cut holes in the lower air channels of this 356 Super speedster. The speedster I took my drivers test for SCCA (1964) had a SC engine with the double flap heater boxes. We drove the race car to the track (probably 175 miles) on Good Year Blue Streak tires raced on the tires Saturday and when it rained we put the recapped spare tire on the left front for better traction and headed back to Wilmington. I believe I saw letters regarding the instillation of the dual lower air channels or maybe it was a letter from Bill Jones suggesting to the factory that cars in the Southwest were it was hot and speeds were high that two opening lower channels should be used. The cost was prohibitive then and most owners (after the first two) did not spend money on their cars. al zim An ex post facto note on swap meets: The seller takes parts off his car that he thinks are good (why would you take off good parts?) Then they are stored in the basement or wherever for a period of time usually over 3 years. Swap meet coming up nearby! The parts are removed and washed. The parts are sold and the new owner has the opportunity to diagnose why they do not work. That is the way it is in the big city. Pretty cool!
Last edited by Al Zim on Tue May 21, 2019 2:22 pm, edited 1 time in total.
 

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Harlan Halsey
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Re: Lower Air Channels 356B & 356C

#4 Post by Harlan Halsey » Tue May 21, 2019 1:44 pm

No, but that's what swap meets used to be for....

Brad Ripley
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Re: Lower Air Channels 356B & 356C

#5 Post by Brad Ripley » Wed May 22, 2019 1:12 am

As Brett indicates, I have never found just when the double-flappers came in, except for the Super 90 when that engine was introduced. I have always assumed from T-6 on, every engine got the double-flappers.

Dick Weiss
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Re: Lower Air Channels 356B & 356C

#6 Post by Dick Weiss » Wed May 22, 2019 10:20 am

Al,

I remember those days when you & I + 2-others raced 4-Speedsters out of the Wilmington shop, and I drove
to open the Mid-Ohio track's driving school for a Regional License in 1962 both ways (180 miles each).
Using the 1-flap air guides (or flapper boxes), I formed downward air guides w/aluminum vs. straight-back hot air gathering around the underside of the car's rear end. However, you don't wanna drive over dusty areas, but it did rain the next day.
Later double flapper boxes could be used, or the 4-vertical end-pieces used on the Euro heat system can do the job of keeping the air exiting at a downward angle.

Dick

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