Vin # and the 409

[64ss409]

I'm not sure about the 340/409 but the 300/327 only came standard with a tach if you ordered a 4 speed also.SteveD

As I understand it, the 340's were the same way, 4sp only? This brings up another question, if they were optional on other engines, has anyone seen a car that had the factory tach with a smaller engine? I don't remember seeing one.
Ron

 

[SteveD409]

Yes, Ron, after going back and reading the ordering info that's the way I see it also--the 340 horse also had to have the 4 speed to get the tach 'standard'.

SteveD

 

[Fran Preve]

As far as I know there's nothing on the accessory plate that indicates the engine and/or transmission, if there were we'd have heard of that by now. I guess we have to put a 300hp/327 car up in the air, and ORIGINAL one, then the same with an ORIGINAL 409 car to see what if anything was changed. Of course there were differences between 250hp and lower hp cars and 409's. This resistor thing has never come up before this last week on this site, I'd hate to think you can identify an original 409 car by whether it had a resistor on the firewall!. How easy would THAT be to do.

PS: Chevytalk never sent me a password.

 

[chevymusclecars]

As I said earlier I think that a 409 car can be told by the cowl tag. I have only been able to obtain one broadcast sheet and cowl tag from a known 1962 409 car and it shows the same accessory numbers on both the build sheet and cowl tag. I looked in the Chevrolet parts books and it shows three engine wiring harnesses available, 6 cylinder, v8 other than 409 and 409. It also shows that the 409 uses a different ignition coil than the other engines. I believe that if enough cowl tags could be pictured and the owner gave what engine they believe the car was manufactured with a reliable database could be made.

Bill

 

[jim_ss409]

I think the difference in the rear suspension that Bobs refering to is in the bushings. It looks like there was two different styles available... standard or heavy duty. The heavy duty (harder) bushings have three notches in them. The standard bushings had no notches. I can't say that I've really done alot of research on this but I can say that my old 64 283 Powerglide car had standard bushings on both ends of both control arms. An Impala with a 300hp 327 that I looked at only had the heavy bushings on the right side control arm. I can't remember what year that car was. My 62 409 convertable has the heavy bushings on both sides. I attached some pictures that show the notches. I only thought to look for these when I read a Service bulletin (page 249 of Alan Covins "By The Numbers 1960-64) that suggested removing the harder bushings if the customer complained about noise and harshness coming from the rear axle. I then noticed a difference in the 62 assembly manual. I don't have it with me right now but it says for a 409 car they installed the same equiptment as the 300hp 327 plus a list of different parts. One of those differences is that the right side control arm was also to be used on the left side. Now This was in 62. But the service bulletin seems to imply that at some point they may have changed over to hard bushings on the right side only and finally to no hard bushings at all by Jan 10th of 64. Sorry but I can't get the service bulletin to scan any better than that.

 

[bobs409]

As I said earlier I think that a 409 car can be told by the cowl tag. I have only been able to obtain one broadcast sheet and cowl tag from a known 1962 409 car and it shows the same accessory numbers on both the build sheet and cowl tag. I looked in the Chevrolet parts books and it shows three engine wiring harnesses available, 6 cylinder, v8 other than 409 and 409. It also shows that the 409 uses a different ignition coil than the other engines. I believe that if enough cowl tags could be pictured and the owner gave what engine they believe the car was manufactured with a reliable database could be made.

Bill

The MSA-1 book does show a "SSK" code that is supposed to be for a SS409 1962+. Anyone have or ever seen that code on a tag?

 

[Impalaguru]

Here's some stuff I thought I might add...
My 63, non-ss, orig. 409 car DOES have the two holes for the lower control arms (Janesville car from the middle of April)
Original 340hp, 3speed and NO tach
Harder, heavy duty, bushings in the rear end.
Resistor on the fire wall
Fuel return line

Here's some things to think about. If the 300hp 327 had a resistor, then wouldn't it NOT have had a resistor wire going to the dist. If someone has a parts book, we could see if it was the same wire as a 283 or 250hp 327 or a 409, for that matter.

Don't forget about the fuel return line in the 63-65 cars. The 327 cars never had that.

As far as the cowl tag goes, would there have been any TOTALLY necessary holes or mods done to the BODY for a 409 engine installation. I can't think of any. I think all cars have the little dimple in the firewall for the resistor bolt.

Ross

 

[64ss409]

If someone has a parts book, we could see if it was the same wire as a 283 or 250hp 327 or a 409, for that matter.

Here is what my parts book has.
Ron

 

[64ss409]

Are all of the applications using the 1931385 .03 ohm resistor, dual point distributors?
Ron

 

[chevymusclecars]

The. 03 resistor with a black dot to identify it is used on all High Performance 348 and 409 engines. The late 62, 63 and 64 cars with single points also use this resistor. The wire between the distributor and coil is not a resistor, the wire in the harness between the fuse box connector and coil is the resistor for six and eight cylinder cars.

 

[jim_ss409]

the 1962 409 cars started out using a right side control arm with harder bushings this may have changed later. i think the station wagons used hard bushings on both sides.

You may be right on about the bushings in 62. I've tried to scan the 62 Assembly Manual but it didn't come out very well. In the list of parts to be used with option 580 (409) it has... 3774122 arm asm. rear axle lower control r.h. (used on left side) But, it looks as if it's been added to the list as an afterthought. This might explain why my car that was built at the begining of April had the hard bushings on both sides.

 

[jim_ss409]

Looking at the rear suspension section of the 62 manual It shows all models getting the arm with hard bushings on the right hand side and only wagons getting the hard bushings on both sides. Then it looks as if they decided sometime later that 409 cars should also get hard bushings on both sides.

 

[jim_ss409]

So let me see if I'm getting this right. It looks like they started out the 62 model year using the 3774121 (soft) arm assembly on the left hand side of all cars except station wagons. The 3774122 (hard) arm was used was used on the right side of all cars, except the wagons, they got the hard arm assembly on both sides.
Then it looks like part way through the 62 model year the 3774122 (hard) arm assembly was added to the list of parts used on the 409 optioned cars. This was to be used instead of the normal soft right side arm.
Then, from what I can gather from the April 64 service bulletin, it looks like they later went back to hard bushings on the right side only for 409s and 300hp 327s. All other cars (except wagons) got the softer bushings. Then as of Jan. 10th 64 they went with the softer bushings on both sides of the 300hp 327s and 409 cars as well.
What do you make of the #3774132 arm assembly? I wonder if it would be considered hard or soft or something in between? Either way it sounds like it would be the replacement for either the 3774121 (soft) or the 3774122 (hard) arm assembly.
I added a copy from the rear suspension page of the assembly manual.

 

[Fathead Racing]

Two holes.

I am really interested in the two positions for the lower control arms, any one have pictures of this?? What holes were used on the cars, upper or lower, and why?? Did Chevy use the same holes on all the rears or did they use different holes for different engine or tranny options?? Very interestiing! :?

 

[SS425HP]

Lower controll arm mounting holes

Ray, I think I remember my assembly manual stating what holes the lower controll arms were to go to, depended on whether the car was an automatic tranny, or standard shift. Please don't ask me why it mattered, cause I DON"T KNOW. But, that was the deciding factor as I remember it.

 

[CDNpontiac409guy]

In my "X" perience ( good pun )... which is owning 130+ 1959-1964 X frame cars... the lower bolt hole position is used only on station wagons.
Why ?
They have a higher ride height. The springs are MUCH stiffer, and somewhat longer.

Come on guys.... this isn't THAT MUCH of a mystery

 

[Fathead Racing]

Bolt holes.

Not much of a mystery but, from a performance point of veiw, wouldn't changing holes give you a different instant center?? Changing holes would change launch!

 

[walkerheaders]

I am really interested in the two positions for the lower control arms, any one have pictures of this?? What holes were used on the cars, upper or lower, and why?? Did Chevy use the same holes on all the rears or did they use different holes for different engine or tranny options?? Very interestiing! :?

i've always used the lower hole. the manual tells you to use the upper? who know what the engineers were thinkin?

i can tell you this, for drag racing, you want your lower control arm angle to travel downward about 3 degrees at ride height. when you drop the hammer on a 4link car, the rear housing rotates rearward and pushes the energy forward in the lower arms. if the arms are downward, then the energy pushes downward on the frame. at the next phase when the housing begins to seperate from the body, then the energy is pushing forward.
when you raise (jack up) a 4link car, the lower control arm angle goes uphill towards the front. when you drop the hammer, the energy pushes upward on the frame and unloads the tires. you ever wonder whats the main cause of wheelhop? ever seen a jacked up chevelle or goat wheelhop like crazy? gee?

this geometry lesson is no secret, every chassis shop knows it.

the angle of the upper arms is even more important. that angle determines the amount of housing seperation on launch.

along with these dynamics at launchtime, the driveshaft would prefer to flop the rear housing end for end rather than propel the weight forward, ever wonder why your mom's car would only burn the right rear? the driveshaft energy lifts the RR and plants the left rear tire. the engine torques the body the opposite direction. thats why you have an airbag stiffer on the right side. theoretically, you would need a shock hard to compress on the RR and a shock hard to extend on the Lrear. the only problem with that however, the launch is only part of the pass. alot of dips and bumps on a dragstrip. the car would drive funny down the track.

there is a picture of the bracket in question at the frame work and more framework thread. it's mvc005f

 

[walkerheaders]

http://www.348-409.com/forum/attachment.php?attachmentid=1932

i hope this shortcut will take you to the picture in question

 

[real61ss]

Hey guys, I've got a question about these holes in the frame for the lower control arms. Was 63 the first year for these holes? Did the use of the double holes continue into 64? I've owned quite a few 61's and I've never seen or heard of these double holes before. I have a 63 Super Sport, it's a 409 now but we're pretty sure it was a 300 hp originally, it only has one hole. Are we on to a way of identifing 409 cars in 63 by the frame? Sorry but this is new to me.
Bob Walker, I looked at the pictures you posted, of course that's a highly modified chassis but it does appear that the bracket with the holes may be original.