Hi It has been many years that I have followed GS Buicks but tomorrow I am going to look at a 71 GS 455 coupe. What numbers on the cowl tag determine that is is a GS and not a Skylark What numbers on the motor show it is corrcet for that car. and so on. I have looked at the car once and it is a very good driver currently on the road . good frame,floors . has had some body work in the past. need your help and some advice. thanks Al
Try the Buickperformance site. http://www.buickperformance.com/guide.htm That is a buyers guide. Here is production figures, specs and VIN breakdown. http://www.musclecarclub.com/musclecars/buick-gs/buick-gs-specs.shtml If the engine is original to the car you can find the last digits of the VIN number behind the power steering pump. The digits should also be on the transmission tag if the tranmission is original. If you want to check the frame here is a link to the frame. http://www.buickperformance.com/FrameNumbers.htm Good Luck.
Thanks Where is the production figures, specs and vin breakdown ? I don't see anything there. sorry. is this a good spot to post thisor is there somewhere better suited. thanks. Al
Unfortunately, 1971 happens to be the year that is difficult document. The VIN does not tell you as much as other years. If it is a 1971 GS, the first 6 digits of the VIN should be 434371. There is no engine code in the VIN. If the engine hasn't been rebuilt, and the block hasn't been decked, the engine code will be stamped into the deck visible between the #5 and #7 spark plugs. Look for TR (GS455), or TS (Stage1). That area can be very dirty, so bring some spray cleaner and a good light. The Rochester Q-jet should be 7041540 for the GS455, and 7041242 for the Stage1 Automatic, 7041243 for the 4 speed. Distributor should be 1112016 (not sure for 71), and the Transmission should be a BS (GS455). If it is a Stage1, the transmission will be either a BB, or an OW. These letters will be on a tag riveted to the passenger side of the case. Good Luck.
That is great , what is the code for a GS 350 just in case it was swapped but the owner tells me it has the original block. what about the heads , do the valve covers need to be off for a code. I do not think he will let me remove them to check. - What is the torque of the 71 GS 455 . I think the HP is 315 if I remember . thanks
I added the link to all of the information you want about the production numbers, engine codes and HP in my post above. If you want the colors for 1970 try this link. http://buicks.net/years/70.shtml There is a link to paint codes.
The VIN does not differentiate between GS 350 or GS 455, or Sportwagon V8, or GSX. The first 3 numbers of the VIN will be 434, 444 will be a Skylark Custom. The casting numbers for the heads(1237661) tell you nothing except maybe the year(1971) of the motor. The Stage1 heads and small valve 455 heads have the same casting numbers. The Engine code is on the block deck, not the heads. The last 6 or 7 digits of the VIN may be stamped into the deck between the #1 and #3 plugs or it may be on the front of the block under the P/S pump or Alternator. More info here: http://www.buickperformance.com/455Blocknmbrs.htm The torque is 450 for the 71 GS455, 460 for the Stage1
Hi guys Thank you for all that info, this morning the owner sent me this sheet he got through GM vintage vehicle services. I thought you could only get these if a car was made in Canada ? this car shows it was made in Flint. So for now this takes all the guess work out . wish he had sent me this yesterday. We are going later this morning to look at . I will let you know about it when we get back. thanks again Al
I was doing some searching and found on Buick.net these 71 V8 455 4bbl GS TA V8 455 4bbl TR V8 455 4bbl GS Stage 1 TS these show the TR as a 455 would that be from say a Riv or something. Also was the TH400 only on the 455 for 71. and what was the code. thanks
Yes the TH400 came with 455s. The TH350 was for small block cars. If transmission is numbers matching (VIN on lower driverside portion, above the pan), look for a 'BA' coded tag on the passenger side (this is from MARCO) on a different post. By reading below it looks like it should be a column shift, bucket seat with a center console. That cool.
OK , well it is not a done deal yet , as last night we were going to take it home and load it in the trailer and it would not start, the starter gave up they have to repalce it . Is the 71 GS grille different from the Skylark grille . what are the correct fender emblems for the 71 GS 455. looking for some good photos as reference. The car has a Therma -quad carb , it has been many years since I have even looked at GS's . was that an aftermarket carb that came through Kenne -Bell ,did it not. thanks Al
The documents you posted are about the only way provide valid proof on a '71. They are the GM Canada import records. Car made in Flint & imported into Canada by GM. The VIN number at the windshield will match the VIN on the document if it's the same car. VIN on the trans. will match the documents as well as the VIN on the engine block. VIN on the TH400 will be stamped into a small flat pad, drivers side, just ahead of /below the speedo cable. The original will read 41H140661. VIN on the engine will read 41H140661. On a 350 it's on the front of the block behind the power steering brackets. Not sure on the 455. I used the same service a few years ago to verify a Stage 1 locally.
What would be the correct intake manifold on the 71 455 and can intake manifolds be swapped from 350 to 455. Can you use an HEI distributor from a late 70's motor. Are the 455 engine blocks the same as the 350. thanks
There is information on the site about casting numbers. I'm not sure exactly where but try a search. I have a brand new rebuilt '71 455 engine I can get the numbers from Monday. 350 & 455 manifolds are not the same, a swap would not work. An HEI from a later engine will work, '73 & later they were stock.
Thanks that would be great. I have purchased the car , I can not make out the numbers on the motor. from what little I remember the intake looks like it might be a mid 70's one. it is very flat. so the motor may not be correct for the car.350/455 do not know yet. it also has a clutch fan . I don't remember those on the 71's ?? It has a Thermo-quad carb which I know next to nothing about . and pair of very old Kenne-Bell valve covers. Al
My '71 350-4 with AC has a fan clutch & 7 blade fan. A 455 in '71 would have come with a 5 blade fan. Look behind the intake, on the top of the block where it meets the transmission. There you will see 350-2, 350-4, or 455 etc.. Another easy check is the valve covers. 350 has 6 bolts, 455 has 5. Original carb. would have been a Quarda Jet 7041544 for 350 & 7041540 in a 455 car. I know very little about carbs. myself but have read others brands are/were available, via aftermarket suppliers. The '71 455 I have is available should you be in the market.
Steve just went out and looked, 5 blade clutch fan on the car. 5 bolt valve covers. to dark to make out the back of the block. but I did make out a large 4 on the drivers side of the block. I can not make out the number stamped in the block between 1 & 3 . I will in the next few days go at it and clean that up. as I said the intake is very flat that is why it makes me think it maybe a mid 70's 455. It does have an HEI in it now , did not know the ram air would not work with it. as it has a chrome one on it now. the car needs work . the past owner was drivng it a little and drove it up here to deliver it. it is a driver. next summer will be sorting things out and enjoying it. Steve My parents live just outside of Mocton , we should be out there next summer. Al
A 71 GS 350 has the same air cleaner as a 70-71 GS 455 except for the foam seals. The distrib is the same except for the tooth count. So it likely has the same clearance issue for a HEI.
