[njsteve]

Both are autos with A/C.

[Firebird 2]

As some of you may know I'm restoring Larry's red 73 SD - I have an ad in the "wanted" section for a correct fiberglass/plastic front valance...any help would be greatly appreciated!

J

[johnta1]

Originally Posted by RicksGTO

Steve, was your friends car an auto or 4 speed? Just wondering if the transmission made the difference on '73 SD's like it did on some if the GTO's in regard to the resonators?

I wonder if maybe the SD TA got them as part of the TA package.
(Formula extra cost?)

[njsteve]

Originally Posted by Firebird 2

As some of you may know I'm restoring Larry's red 73 SD - I have an ad in the "wanted" section for a correct fiberglass/plastic front valance...any help would be greatly appreciated!

J

Ask for Polyethylene only (otherwise it's a reproduction) :-)

NJSteve (a.k.a. PolySteve)

[Larry Navarro]

John, keep us posted on the progress.

[transam1972]

I know I will get this name wrong but a while back one sold, and he said he had another that needed work...I did not really want a damaged one..not saying that's bad...tough to find perfect poly .....try,ready?!...TELLYSHEVELLI

[REFORMULATED]

Are the OEM in line resonators or should I say lead pipes on the cars that got them 2.25" or 2.5". Anyone repro them?

Originally Posted by RicksGTO

Steve, was your friends car an auto or 4 speed? Just wondering if the transmission made the difference on '73 SD's like it did on some if the GTO's in regard to the resonators?

[RicksGTO]

not sure on the size on the original systems. The Parts Place Inc. makes a repro system for the SD exhaust with resonators so he might have the resonators for sale separately.

[63Longtop]

Originally Posted by johnta1

A lot of the 1974 SD blocks were cast like yours.
1973 had a lot of the 72 cast dates, but still some 74 had them.

What is the EUN on it?

EUN Input Form

To see some others like yours:

EUN Search

Type 1974 in year and 490132 in block code.

EUN is 373423

[frank.g]

Hello everyone. Long time viewer, first time posting. 27 year owner of an unrestored, Brewster green SD. Re: resonators, another source is Gardener exhaust. They only sell complete exhaust systems, though. You should also know that the resonators are butt welded into the system, not clamped on. So, they are 2 1/2" inlet/outlet.

According to what I have learned over the years, Pontiac made up the initial run of the exhaust systems with the resonators that were used on the 73's, then decided the resonators did little for the cars, so left them out. The change over occurred near the end of the 73 model run. As far as I know, no '74's got the resonators, and the service replacement exhaust system for the 73 and 74 excluded the resonators.

[hada76]

Originally Posted by frank.g

Hello everyone. Long time viewer, first time posting. 27 year owner of an unrestored, Brewster green SD.

welcome, good info...now post some pics!

[Rocky Rotella]

Originally Posted by frank.g

Hello everyone. Long time viewer, first time posting. 27 year owner of an unrestored, Brewster green SD. Re: resonators, another source is Gardener exhaust. They only sell complete exhaust systems, though. You should also know that the resonators are butt welded into the system, not clamped on. So, they are 2 1/2" inlet/outlet.

According to what I have learned over the years, Pontiac made up the initial run of the exhaust systems with the resonators that were used on the 73's, then decided the resonators did little for the cars, so left them out. The change over occurred near the end of the 73 model run. As far as I know, no '74's got the resonators, and the service replacement exhaust system for the 73 and 74 excluded the resonators.

It makes you wonder if the resonators (or attenuators, as Pontiac called them) had something to do with taming the snarl of the intended 041-spec camshaft.

[njsteve]

Originally Posted by frank.g

Hello everyone. Long time viewer, first time posting. 27 year owner of an unrestored, Brewster green SD. Re: resonators, another source is Gardener exhaust. They only sell complete exhaust systems, though. You should also know that the resonators are butt welded into the system, not clamped on. So, they are 2 1/2" inlet/outlet.

According to what I have learned over the years, Pontiac made up the initial run of the exhaust systems with the resonators that were used on the 73's, then decided the resonators did little for the cars, so left them out. The change over occurred near the end of the 73 model run. As far as I know, no '74's got the resonators, and the service replacement exhaust system for the 73 and 74 excluded the resonators.

Hey Frank! Did you get your differential seal done and back in yet? I haven't touched my car since I got back from the show in Chicago in November....I've been working on the truck, which runs great now....just in time for the wife's car to start breaking down.

[frank.g]

Originally Posted by Rocky Rotella

It makes you wonder if the resonators (or attenuators, as Pontiac called them) had something to do with taming the snarl of the intended 041-spec camshaft.

Rocky - as good of a theory as one can up with 40 years later. I know they had "problems" at the time with the EPA drive-by decibel test. I'm sure you know it was the reason why the hood inlet was riveted shut. The attenuators seem to do little on the "Y" cam. I have a friend who put a "K" profile cam into his SD - but he also put in a low restriction exhaust system. Snarls plenty - it would be interesting to know if the attenuators would affect it.

[njsteve]

Originally Posted by hada76

welcome, good info...now post some pics!

go here:

http://forums.maxperformanceinc.com/...71844&page=203

[frank.g]

Originally Posted by njsteve

Hey Frank! Did you get your differential seal done and back in yet? I haven't touched my car since I got back from the show in Chicago in November....I've been working on the truck, which runs great now....just in time for the wife's car to start breaking down.

Hi, Steve. Rear is in, brakes are back in, half the exhaust system is in. Have to get the left exhaust manifold off, and that's where the project stalled. Been plowing snow ever since. LOL. Glad to hear the truck is living again. I followed it's saga from the wings. I had to laugh when I learned that it was fixed about a mile from my office.

Also, I got the plastic solder iron. Read the directions, looked it over, and set it aside until the spring. Gonna be leg ironed to my desk soon. Hope your wife's car is nothing serious. Gotta take care of those Hemi's. Can't believe you haven't found something to do on the SD for almost three months!

[njsteve]

After getting the diesel's head gaskets replaced at the dealer, I upgraded the exhaust system, air intake box, and replaced the remainder of any lines that could eventually rust. She runs a bit peppier now. Wife's 300 AWD needed front half shafts and wheel bearings...a week later the front driveshaft started rumbling. Hey, it does have 140,000 on it and has been relatively trouble free til now....

As for the SD, I do need to replace a couple of worm clamps that someone put on the rubber fuel pump lines running under the engine. I need to locate some original, factory spring clamps - red and green, 2 of each, I think?

[frank.g]

Steve - I can take a look at mine and tell you what's on it. I may not be able to tell color though. Z bard was sprayed everywhere back in 1973.

[Brewster]

From what I seen, read, heard all 73 built cars had resonators however 74 cars and all over the counter replacement sd exhaust system did not.
Steve, your exhaust system might have been replaced at one time or another. Whats the muffler date code?

[njsteve]

Never replaced. 1973 date codes. Not a bolt turned since August 1973 when Enrico loosened the chrome tips and adjusted the angles. (One tip still rubs the lower rear quarter on acceleration). Nothing's better than being able to pick up the phone and talk to an original owner with a photographic memory.
:-)