1956 Special High-Lift cam option code 449

[Ernest C.]

Has a survey ever been done to try to determine how many 56s with the GU option still remain? Thanks

[Richard M.]

Re: 1956 Special High-Lift cam option code 449

Ernest, Data shows a total of 111 265CI engines were made with RPO 449 Hi Lift Cam. It had to be ordered with RPO 469 2xWCFB & 3 Speed*.

RPO Data states:
46 ECL A
65 ECL B

I'm unaware of what the ECLs represent.

I don't know of any recent surveys, but you may find some data with more info HERE.

This file lists a few GU cars in the survey. 1st one vin 2509. (1509th car)
Mike Hunt RP56-7 VetteVues Article-1956 Survivor VINs-OCR.pdf

Rich
(* according to the Spec Guide)

[Ernest C.]

Re: 1956 Special High-Lift cam option code 449

Thanks Rich, I was able to print the Mike Hunt article, but it only counted 97 cars total. I have a GU car, but it is not included in that article. Thanks again Ernie

[William F.]

Re: 1956 Special High-Lift cam option code 449

Is that the Dontov cam or something else?

[Ernest C.]

Re: 1956 Special High-Lift cam option code 449

yes it is the Duntov cam

[Joseph L.]

⁰ duration (228⁰ intake and 230⁰ exhaust duration @.050"), .394" intake and .400" exhaust gross lift, and 108* lobe separation.

The 1956 cam used in GU motors is similar to the 097 cam. The GU cam (P/N 3734077) had 287⁰ duration (228⁰ intake and 230⁰

[Ernest C.]

Re: 1956 Special High-Lift cam option code 449

Joe, it would be interesting to compare these two cars, but I think your 57 would outperform in every way. If you were near Pa I would volunteer my 56. Ernie

[Richard M.]

Re: 1956 Special High-Lift cam option code 449

Joe, Good research info thanks for the cam education. One thing I never realized, that all 55-56 265's used solid lifters. Never knew that until I read the Spec Guide and your confirmation about mechanical cams.

Since the early Mike Hunt survey only shows 5 cars....

2709
2720
3224
3638
4126

and Ernie's other 1, that's quite a rare package you have of only 111 total cars.

It would be nice to know what the RPO 449 ECL A & B totals refer to. Since all 240 HP GU engines required a 3-Speed, maybe A & B refer to rear axle equipment, i.e. RPO 471(3.27:1) or not. A guess. There were 155 RPO 471 Corvettes.

Rich

[David B.]

Re: 1956 Special High-Lift cam option code 449

I have mentioned this in past threads but will repeat and hopefully someone will finally believe my explanation. Years ago the Blackbook and NCRS failed to breakdown or did not understand what 46A and 65B meant. So they simply assumed the 111 total was all Corvette. To clear up this misunderstanding and answer Rich's question. The A represents Pass. GT engines and the B represents the Corvette GU engine. Have known this for many years but stopped trying to explain. I am very very familiar with the 240 HP '56 engine. At one time was going to write an article (with photographs) on one of the '56 Sebring engines (they were GTs) I had to replace the crankshaft because of a problem the team encountered while practicing. There is a lot more to this story but the good part for 56 Corvette owners with GU engines you are now even more rare then you thought.

[Gary C.]

Re: 1956 Special High-Lift cam option code 449

Rich,

RPO 469 info attached. 471 was a rear end and only 1 was produced. IIRC standard rear gears for 1956 were 3:55
1956 RPO 449 and 471_Production Qty.jpg

Gary
....

[Michael H.]

Re: 1956 Special High-Lift cam option code 449

All,

Need to include Bob Kunz barnfind 56 S/N 2762 which is one of 111. Car is pretty much all original with 41,000 miles on it. Bob sold the car to the grandson of the original dealer Paul Luehrs Chevrolet of Mascoutah, Illinois who sold the car new in June 1956.

https://www.motortrend.com/features/1604-possible-1-of-111-1956-corvette-with-duntov-cam-pulled-from-missouri-basement

Mike

[Ernest C.]

Re: 1956 Special High-Lift cam option code 449

My car is 3263 which could be added. Ernie

[Richard M.]

Re: 1956 Special High-Lift cam option code 449

I have mentioned this in past threads but will repeat and hopefully someone will finally believe my explanation. Years ago the Blackbook and NCRS failed to breakdown or did not understand what 46A and 65B meant. So they simply assumed the 111 total was all Corvette. To clear up this misunderstanding and answer Rich's question. The A represents Pass. GT engines and the B represents the Corvette GU engine. Have known this for many years but stopped trying to explain. I am very very familiar with the 240 HP '56 engine. At one time was going to write an article (with photographs) on one of the '56 Sebring engines (they were GTs) I had to replace the crankshaft because of a problem the team encountered while practicing. There is a lot more to this story but the good part for 56 Corvette owners with GU engines you are now even more rare then you thought.

Rich,

RPO 469 info attached. 471 was a rear end and only 1 was produced. IIRC standard rear gears for 1956 were 3:55

Gary
....

Great info as usual David. Thanks for clarifying that. ECL mystery solved.

Gary's Bill of Materials(BOM) shows "B: - ON 2900", 2900 being Corvette. The "A: - ON #'s" are non-Corvette Model numbers. Excellent reference.

To summarize, only 65 1956 Corvettes with RPO 449 were produced. Wow, very rare.

Thanks Gents,

Rich

[Steven B.]

Re: 1956 Special High-Lift cam option code 449

Thanks Gary! Ever see any public or internal info of SR-1 availability? Thanks! Steve

[David B.]

Re: 1956 Special High-Lift cam option code 449

What would you like to know?