ah64pilot

I would like to know what cars got the 3918061 & 3918062 Frame reinforcement bars in 1972. I looked in the '72 Assembly manual and this is all I find:

When looking at the Assembly Manual the "rear stabilizer shaft" says directly underneath "35FE2". However, the "Frame Reinforcement" doesn't say anything specific. It does have "(32, 36, 4200 with 35L75)" underneath it.

Does the parenthesis mean that they go on cars with 455's in them? If so, why does my 2 owner '72 Supreme (factory 350 (L34) engine) have them? I am not complaining that I have them, but I was under the impression that it was an upgrade for the FE2 suspension package. I know they weren't put there by the previous owner, I'm fairly certain Mrs. Wilson didn't upgrade her suspension as when I got the car in 1990 she was 85 years old.

Please, educate me

oldspackrat

Do you mean the small braces at the front of the rear lower control arm? If so I have a 1972 4 door Cutlass with a factory 455 4bbl that has them. It also has the front fender braces from the cowl to the fender. It is a 69,000 mile car and has not been messed with.

ah64pilot

Yes, those are the ones I am talking about. I know my car has them and it is a 2 owner car, me being the 2nd owner, and I know I didn't put them on. So I know my '72 Supreme came with them from the factory, what else did in '72?

I always thought they were an upgrade but it appears maybe they weren't for '72? It's odd though because Allan's car doesn't have them, but it was a 2bbl. Maybe they didn't come on L32 cars, just L34 and above?

davebw31

ah64pilot:

What build date do you have on the Fisher cowl plate?

ah64pilot

2nd week of February 1972

davebw31

Since chassis and body styles were going to change greatly in 73'. There were a lot of pre-1973 parts that were not going to fit. So were options for mandatory dealer cars. Soooooooooooooo the line was putting parts/options on cars just to get rid of them. I had a 72' Supreme convert. that had the rare cloth seat inserts front/rear option (think Hounds Tooth like Ch**y Camaros) and had the heavy duty std. wheel option! Being that your car was a 2 owner car it is very possible your car got the "treatment". It should be noted that due to frame cracking issues prior to 72' on all 455 and 4 speed option A body cars got the rear braces. Only 455 got the fronts. 70' 455, W30, W31 auto. or stick got the rears. Again 455 only got the additonal fronts. If I remember correctly I got an Engineering Change Order that said starting with late model run cars after Jan 30, 1971 all 455 equipped A body auto. or stick got the front and rear braces. Do not think it included SBO except for stick 4 Bbl. cars.

ah64pilot

Well that makes sense. My car IS a 2 owner car, I am the 2nd owner lol! But originally it came with green cloth interior but the cloth was the paisley looking silk like cloth. I hated to replace it but it was starting to tear. My car is also an Arlington car, and I know that Arlington didn't build any of the W cars...at least that's what I've noticed. So maybe you're right, they may have just gotten rid of the extra parts.

I do know that the '73 and later rear frame braces are different than '72 and prior so your explanation could be feasible.

I checked my '72 Convertible and it does not have the rear frame braces (original L32 car) built 1st week of May 1972 in Lansing.

oldspackrat

I've always wondered/suspected that they did what I call "option dumping" on the '72 cars. I've seen a ton of them with tilt, cruise, p. windows, etc.. It would make sense for the factory to not have a bunch of this stuff sitting around when the new models used very little if any of it. Dave, your knowledge is amazing, you should write a book so this info doesn't get lost to the ages.

Allan R

Steve, the parts you are talking about are the body to control arm braces and you're right, they are part of a package upgrade. The braces are specifically for cars with an FE2 suspension (braces, boxed control arms and rear sway bar). The 32,36 and 4200 refer to the models. 32 is the base Cutlass, 36 is the Cutlass S and 4200 is the Supreme.

If you look to the left of that box it also has a A with a circle around it. That's a reference to the picture on the top left that also shows the combined sway bar attachment.

oldspackrat

Allan,
I'm not disputing your info. above, but I question why my '72 4 door has those braces but not the boxed control arms or rear sway bar? I haven't checked to see if the front sway bar is the FE2 one or not, but I'll try tomorrow as now you've piqued my curiosity.

Allan R

I'd like to know too. FYI, The FE2 suspension appears to be only available on coupes according to the 72 SPECS, but then I may be reading that wrong.

Here's the guide info that specifies the heavy duty rear lower control arms (boxed). Could be that someone in the cars previous life added the braces to stiffen the cars rear end handling? The braces bolt to the outside of the control arm and body cross member so it's an easy add on.

oldspackrat

I don't think they've been added. The whole car is weird. I did another thread on it with more details, but the short version is it's a '72 4 door hardtop sedan? no post around the good glass. Factory 455 4bbl, th 400, posi with as of yet unknown ratio. 69,XXX orig. miles. W & Z? manifolds, notched valve covers, 4 core top plate & core support, but 3 core radiator with 4 core tank on pass side & 3 core tank on driver side, original starter, battery cables, heater hoses, etc...
It has the front big block fender braces & the rear lower control arm braces. Maybe they ordered it this way(455, th400,posi) to tow, but no trailer hitch or trailer light provisions are evident. It also had disc brakes, tilt, clock, light package, AC, power trunk, f & r bump guards, deluxe seat belts & probably more. Sounds like someone wanted a 4 door 442. I'm sure this car surprised a few people in it's day!!

Allan R

Ah, I remember the car now. I want some parts off it
If it was a tow car? Wouldn't it have had the F41 suspension instead? Check the wheels. If they're OEM they should be the HD ones - I think they handle the larger tires for load distribution and traction?

ah64pilot

I spoke with Joe tonight and he was saying that the Rear Suspension support brackets were NOT part of the FE2 suspension package. He said they were part of the big block package and came on big block cars, along with the front fender supports and different stamped rear upper control arms.

This is all hearsay to me, but it seems to be confirmed by the "(32, 36, 4200 with 35L75)" written underneath it. So, maybe it is plausible that all big block cars came with them, and during the later '72 production year the "excess" parts were being added to all of them to deplete inventory.

Packrat, that would also explain why your car has them as it is a factory 455 car. Still no definite answers for mine, but I'm leaning towards Dave's idea. When I change out the upper control arms I will check the stamping to see if they are big or small block arms.

Allan R

Really? There's no stamping on any of the CA's I did last year and I went right down to metal. I've never even heard of BB or SB OEM arms on a 70-72 Cutlass.

I'm not sure Joe is right about those braces either. I've seen them on 350 cars that were original, so I don't think it's exclusive to 455s. Not so sure they were just dumping options into cars back then to clear inventory, but then again I wasn't there so I can't argue that.

davebw31

To add to joesw31 comments, there are two upper arms, one being wider or more HD then the other. The HD has HK and the other std. arm is stamped JK on the side of the arm.

ah64pilot

I have seen them on 350 cars that are original as well, mine lol! That is what prompted this thread. I have the build sheet and everything for the silver car, it is NOT an FE2 car and is a factory 350 4 bbl (L34) car with a 2.73 open rear end. However, it came from the factory with the rear frame braces and I have no clue why. Dave's explanation of parts dumping is the only one I have gotten so far, and it does seem plausible...but you are right, it's not a definite answer.

I like this dialog! I am learning a lot...let's keep it going and maybe, just maybe, we'll get to the bottom of my '72 Supreme with rear frame support brackets

Allan R

Well I got news for both of you. My 72 rear upper control arms are stamped NK. So what is that? HD or not. I'd like to know what that width measurements are that determine reg vs HD.

ah64pilot

Oh no!!! LOL! Now we're really getting things stirred up haha! Allan, these guys are gonna hate us '72 guys for breaking out of the norm

Now you've got me curios, I'm gonna check mine when I get home to see what the control arm stampings are. I'm loving this! Its like investgative history

Allan R

Your car was a 455 to start with though wasn't it? Be helpful if you could get a measurement across the insert for the bushings at both ends.

ah64pilot

Oh heck no Allan, L34 born...I raised it to become a 455 car lol! I'll look at my UCA's and see if I can't find that stamp...I'll also measure the inserts if possible.

That's why I'm asking all of this...my L34 car has rear suspension supports from the factory. I am the 2nd owner, the original owner (lady) we got it from was 83? in 1990 when we got it.

Seff

My '71 Supreme with a numbers matching 350 came with FE2 suspension and the frame reinforcement bars in question. Car was imported to Holland and sold there. I can go get the VIN off it if that helps.

ah64pilot

Seff, you would need the build sheet to know if it came with FE2 or not. You don't happen to have it do you?

Also, I figured something out about the '72 cars and why the upper control arms might be different in the assembly manual from earlier years. Remember that the "442" was an option? Yep, in the 1972 assembly manual all 32, 36, and 42 series got the NK uppers, all 4800 series got the NJ.

Seff

No, I don't have any papers for that car. It has a rear sway bar and boxed rear arms, and the reinforcement braces. 2.56 posi as well, which I'm not sure was a factory option, actually? Could indicate that rear end work has been done in its lifetime.

jensenracing77

this NK set are from a Vista with an original 350. would it have them because it was a Vista?

100_0492-1.jpg?t=1349481145

ah64pilot

Uh, that is an NJ control arm...did you post the wrong picture?

jensenracing77

lol, i ment NJ... these NJ uppers were in a 350 vista.

Allan R

Steve already busted ya on the NJ so the simple answer is Yes, the NJ control arms are specifically for the 4800 (Vista Cruiser). I don't see anything that specifies a different control arm for 455 or 350 production of that line. Don't you just hate it when the J's look like K's and you're too tired to notice? That control arm looks to be in very good condition BTW.

jensenracing77

they were out on an Arizona Vista so there is virtually no pitting. most all the spots you see are surface rust from being bead blasted and not painted. shame on me.

ah64pilot

Per the 1972 Assembly Manual they would be correct. The Vista Cruiser 4800 series (2 seat 4856, 3 seat 4866) would have the NJ control arms.

Keep in mind, we are talking about the '72 model year. Earlier years we think are different and are broken down into engines and W packages. For 1972 they were options so the assembly manual subdivides suspension components to different body styles instead.

ah64pilot

Allan, we still haven't learned why my original 350 car has the frame reinforcements. Joe and I are thinking it was either parts dumping or just a mistake at the assembly line. It would've cost more (timewise) to go back and remove them so they were just left on.

I am convinced, however, that the rear suspension frame supports were NOT part of the FE2 package in 1972. Per the assembly manual, they were reserved for big block cars.

What we gather from the earlier assembly manuals and the parts book is that the cars prior to 1972 that got the frame reinforcements were 442 cars and ANY car with factory installed OAI (W-30, W-31). So our cars would NOT have had them unless they were ordered with a 455 in 1972. (I think I got that right...you might see an edit if I got it wrong)

Allan R

Well shiver me timbers mate! I'm still going to put them in my 350 car as an upgrade. It should stiffen the rear a bit more than it is now and those 3:42 gears will probably put them to the test a few times. By any chance did you notice what grade bolts were used to secure them at the top? I know they get fastened to the front of the rear lower control arm with the control arm mounting bolt/nut.

ah64pilot

Allan, at the top they are secured by the control arm bolt / nut. They run from the front of the lower to the front of the upper. See assembly manual diagram above.

Allan R

Hmmm, ya mean like this? MUCH easier to work with once you yank that ol body off the frame.

BILL DEMMER

other than umi tubulars, does anybody make these?
anybody got a decent used set for sale?


bill

ah64pilot

I'll sell you the one's off of my car for $100 then I'll buy some tubulars lol!

BILL DEMMER

gee, that sounds like an awesome deal except opgi sells re-pops for $90.xx


bill

sammy

What is opgi?
Just purchased the boxed control arms, MAW put in frame braces..

Ted

GAOldsman

www.opgi.com a reproduction parts place in California

Allan R

Ted, what Scot ^^ said. But shop around. OPGI typically has amongst the highest prices for these parts. Look at Parts Place.