74 Big Block Air Deflector Extension Question

[Victor S.]

Would the front air deflector extension have been installed at the factory on a 74 BB car with air conditioning or would this have been done at the dealer in response to a service bulletin? It says in the NCRS judging guide that the deflector extension may appear on LS4 equipped cars after Jan 73 - but was wondering if the factory automatically installed these extensions on all A/C BB cars for better engine cooling??

Thank you,

Vic

[Russ S.]

Re: 74 Big Block Air Deflector Extension Question

Earlier cars were dealer installer as per a service bulletin. Not sure about later 73 and 74 cars.

[Terry M.]

Re: 74 Big Block Air Deflector Extension Question

I can't imagine that extension would have cleared the obstructions on the transport vehicles (train or truck) and thus I would expect the extension would have been shipped inside the car and installed by the dealer as part of new car preparation. That, of course, is different than if the extension was added as part of a Service Bulletin. Generally Service Bulletins will give a date or even sometimes a serial number at which the factory began to include the item as part of regular production.

[Russ S.]

Re: 74 Big Block Air Deflector Extension Question

Service bulletin # 73-T-28 dated May 14 1973

I can't imagine that extension would have cleared the obstructions on the transport vehicles (train or truck) and thus I would expect the extension would have been shipped inside the car and installed by the dealer as part of new car preparation. That, of course, is different than if the extension was added as part of a Service Bulletin. Generally Service Bulletins will give a date or even sometimes a serial number at which the factory began to include the item as part of regular production.

[Tom R.]

Re: 74 Big Block Air Deflector Extension Question

I can't imagine that extension would have cleared the obstructions on the transport vehicles (train or truck) and thus I would expect the extension would have been shipped inside the car and installed by the dealer as part of new car preparation. That, of course, is different than if the extension was added as part of a Service Bulletin. Generally Service Bulletins will give a date or even sometimes a serial number at which the factory began to include the item as part of regular production.

So how long is a service bulletin in effect? Russ states the relevant bulletin is dated May 14, 1973 so is it in effect until that option expires?

[Terry M.]

Re: 74 Big Block Air Deflector Extension Question

Service bulletin # 73-T-28 dated May 14 1973

Any way to post a copy of that TSB? I am currently unable to get to my TSBs.

[Paul O.]

Re: 74 Big Block Air Deflector Extension Question

Service bulletin # 73-T-28 added 2nd page

[Victor S.]

Re: 74 Big Block Air Deflector Extension Question

So if I'm interpreting correctly the service bulletin was issued only for earlier 73 BB cars - as the bulletin states cars after those early 73's had them installed already at the factory? Is that correct?

[Russ S.]

Re: 74 Big Block Air Deflector Extension Question

Thank you for posting Paul. Having just moved from Colorado to MN, everything is in a disaray here.

Service bulletin # 73-T-28

[Paul O.]

Re: 74 Big Block Air Deflector Extension Question

So if I'm interpreting correctly the service bulletin was issued only for earlier 73 BB cars - as the bulletin states cars after those early 73's had them installed already at the factory? Is that correct?

Victor as indicated in the S/B after VIN 10722 this additional flap was installed at the factory. If your VIN is earlier it could have been installed as part of the S/B. Or the original owner's never had the S/B complied with.

[Victor S.]

Re: 74 Big Block Air Deflector Extension Question

Thanks to all for answering my questions - much appreciated!!

[Peter G.]

Re: 74 Big Block Air Deflector Extension Question

Thanks Paul. I was about to go get the one Terry sent me years ago for my car out of its "Baby Book". I always have it with the car for judging, but no judge has ever asked me about it?? They know it's different...I guess maybe they just know me.

[Mark E.]

Re: 74 Big Block Air Deflector Extension Question

QUOTE=Paul Oslansky (18046);818476]Service bulletin # 73-T-28 added 2nd page[/QUOTE]

Had anyone seen or used the flex fan referenced in this bulletin?

How well does it perform? What does it look like?