[Held for Ransom]

Assembly manual sheet.

[Bentwheelbob]

HFR - Yeah, I was looking at that page earlier, but I can't get clarity around which is correct due to the abbreviations (what is FIR), and each PN callout refers to the M40 transmission??? I have large format versions of the assembly manual below.

Another question - also pictured below is the spacer that was between the AC bracket and right cylinder head. Is that the factory style spacer? It looks like something Steve might have gotten from his kids Playdough machine....

[Held for Ransom]

FIR is Firebird. The sheet was made for A-, F-, and B-bodies.
So, Firebird w/LS5 (455 HO) and M40 (THM400 auto. trans.).
And, that style spacer was used, I just don't know what years.

[Bentwheelbob]

I wonder why the Fbody would have a different pulley if everything else is the same? seems like the accessory brackts would be identical. I knew that M40 was the TH400. I am puzzled they don't have a listing for manual transmission.

[njsteve]

That is the correct spacer and I got it out of a box of Lucky Charms, I'll have you know! ;-p

It goes here, behind the big compressor bracket (see red circle)

[eaglesan13]

1970 Firebird also uses that spacer.

[Bentwheelbob]

Thanks for the clarity on the spacer. I know where it goes, but I'm just surprised that all other spacers are round, machined parts, and this is so different. The 1978 spacer is round, machined like the rest. I learned something which is cool.

I did find my bag of valance parts, so I think I am good to go there. I still need to figure out the pulley though. We got a lot done today on the deconstruction. The interior is all stripped, and the drivetain is just an hour or two from being ready for removal. I went ahead and stripped out the nasty interior tar paper underlayment and will replace it with dynamat. No big surprises which is good.

[formula400]

Bob, weld the holes and redrill. Or i know that i stripped a 73 with the HD charging at muscle car alley when i was there. The pully should still be there, i can call the new owner too look.

[Held for Ransom]

Posting the legends for '73 and '74 pulleys.

[165th]

Wow, this looks like a great project. Thanks for posting all the pics and good luck with the refresh!

[Bentwheelbob]

Originally Posted by 4birds

Bob, both of my 72 455HO a/c cars have the same 485397 YN as yours, and I believe they are correct. As Steve mentioned, the black car has the 80A alt with the idler pulley. I don't know if they used the same water pump pulley. I would think they would be the same. Maybe someone can look it up in an assembly manual or GM parts list to verify.

4Birds - Are your cars with 485397 manual or auto transmission?

Originally Posted by Formulabruce

This blows my mind!! Get your zip lock bags and markers ready! If bolts could talk! I probably have the bracket for fuel 72. I will look on a couple cars. Good luck. Hope to see it done in 2017 !

Bruce - any luck finding the fuel line bracket?


No real progress on the car the last few days as I have been busy winding down things at work. Hope to take Friday off and get this thing moving again. I do have a tons of parts ordered and moving toward the garage. This car will be so much easier than the Gold Car because of the experience I gained on it. I actually have some idea what I am doing, and know what I need. I am really looking forward to sending the car off, and even more so getting it back.

I would love to find an FH code original radiator. It has a Spectra now with the trans cooler connections, and worst case I will put in a radiator designed for a MT car. I'll do a seperate post begging for an FH radiator or FH tag, and CV and IA tanks.

[4birds]

Bob, both my a/c cars are automatics with the 485397 YN pulley. I dont know why the 80A alt setup using the idler pulley would use a different w/p pulley. I would assume alll the a/c cars would use the 485397 YN pulley, regardless of transmission.

I can't remember if Steve had the build sheet for the car. If you have it, it will show the pulley codes in box 33 for the crank and fan.

My T/A is a M22 car with no a/c. That's why it has the bigger 481039 XF pulley. Mike's Sundance M22 no air car should have this big pulley also.

[Bentwheelbob]

Originally Posted by 4birds

Bob, both my a/c cars are automatics with the 485397 YN pulley. I dont know why the 80A alt setup using the idler pulley would use a different w/p pulley. I would assume alll the a/c cars would use the 485397 YN pulley, regardless of transmission.

I can't remember if Steve had the build sheet for the car. If you have it, it will show the pulley codes in box 33 for the crank and fan.

Well, I found this old thread from 2006 that you actually originated where OPH indicated that this pulley differed based on auto or manual. Here's the link and copy of OPH's post. Also, there is not a build sheet.

http://forums.maxperformanceinc.com/...ghlight=485397

"09-04-2006, 01:57 PM
'ol Pinion head
Ultimate Warrior Join Date: Apr 2000
Location: Future NATION of TEXAS!
Posts: 6,713


485397 is the odd 5 3/4" diam w/p pulley, used on auto a/c 455HO Bird applications.
481040 is the common 6 5/8" w/p pulley, used on 4 spd a/c 455HO applications.
481038 is the common '71+ a/c appl crank pulley.

May have a few more 485397's.
Ship out a few 037, 038, 039 & 040 pulleys each month."


================================================== =======================

Then there is this from the 1973 Master Parts Catalogue. What is the "HT" that is listed? Also, what is meant in the 1971 listing where it shows the pulley changing "First Jobs" and "After Jobs"?

[4birds]

Interesting. I believe the "HT" means heated rear glass (which gives you the 80A alt & idler pulley) The way I am reading it is the 485397 would be correct for the Black car. (455HO with a/c and HT)

In other words, ALL 72 455HO Air Conditioned cars use the 485397. Including automatics and manuals. And if you have a non-455HO car (350, 400 engines) but you ordererd HT (heated rear glass)-you would get the smaller 485397.

The 481040 pulley would be for all other cars (350 & 400's) with A/C.

I'm looking at 72's specifically. Am I interpreting this correctly?

[Held for Ransom]

I thought HT was Hydramatic Transmission meaning automatic.

[njsteve]

Any time you had both A/C and the heated rear window defroster, the 80 amp setup was mandatory.

I have also heard from several people over the years that cars destined for delivery in NY state were required to have that rear window defroster as a mandatory option. (BTW, my Gramma's car was sold new in Yonkers NY and has the A/C and rear window defroster with the 80 amp alt).

[johnta1]

I agree with Mike (HFR) on the HT.

[Formulabruce]

Originally Posted by njsteve

Any time you had both A/C and the heated rear window defroster, the 80 amp setup was mandatory.

I have also heard from several people over the years that cars destined for delivery in NY state were required to have that rear window defroster as a mandatory option. (BTW, my Gramma's car was sold new in Yonkers NY and has the A/C and rear window defroster with the 80 amp alt).

AC and PW can get you the 80 amp set up as well. Also all 3 ( AC PW and the Rear defrost grid) will get you the big alternator.

HT is the rear glass heated ( there is only one ac upper pulley for this car, auto, or standard shift) # 486397 is for an auto or standard
Jobs= Jobbers , and parts shows there was a revision ( assy manual rev sheet), and a parts pick order change ( different part, and possibly number, and possible manufacturer, in the engine sub assembly line. ( looking at the '71 info)
Bottom line, the 72HO 455 with the 80 amp uses a small pulley similar to the 1970 400 AC pulley size. I could guess this is to keep the heat down more when the Lead was coming out of the fuel.. ( IMHO)

[Bentwheelbob]

Originally Posted by Formulabruce

Bottom line, the 72HO 455 with the 80 amp uses a small pulley similar to the 1970 400 AC pulley size. I could guess this is to keep the heat down more when the Lead was coming out of the fuel.. ( IMHO)

Now that's an interesting thought that may explain a few things. Smaller pulley equals faster belt speed....The one common complaint about cars with the 80amp idler pulley is the issue of belt squeal. I wonder if this squeal might be more a function of belt speed instead of the idler pulley? I think I might try the 481040 pulley just to see what happens. The black car has always run cool, so I doubt the change in belt speed will have a material effect on engine temps.

[Formulabruce]

Originally Posted by Bentwheelbob

Now that's an interesting thought that may explain a few things. Smaller pulley equals faster belt speed....The one common complaint about cars with the 80amp idler pulley is the issue of belt squeal. I wonder if this squeal might be more a function of belt speed instead of the idler pulley? I think I might try the 481040 pulley just to see what happens. The black car has always run cool, so I doubt the change in belt speed will have a material effect on engine temps.

I believe That will put the adjuster on the Idler at its tightest setting, with same belt.. The 73 Water pump pulley is more common and used for many years after. With a 160 or 170 T stat , I would assume it will be fine