RPO, Build Sheet, & More!

[chevyaddict]

Hi all;
Ok, so I searched the forums for RPO codes and build sheets. I also looked under the tech center - model center for info and I'm finding inconsistencies all over the place so perhaps you guys can help me out.

First, I read on one thread that they didn't put build sheets in 68 Corvettes, and yet on another thread they did. So did they or didn't they? Are they on the gas tank if they are?

Secondly, is the build sheet the only way for me to extract RPO Code information? I assume yes but I'd like confirmation of that.

Also, the tech center here lists the HP block as a 350 HP, but in two other sources that suffix code is listed as a 300 HP. How can I find out for sure? Also, I'd like to findout camshaft lift and duration, compression, confirm the rear axle ratio and just more specifics..... any ideas how I can find that info easily?

Danka all!!!

 

[GaryS]

Hi all;
First, I read on one thread that they didn't put build sheets in 68 Corvettes, and yet on another thread they did. So did they or didn't they? Are they on the gas tank if they are?

Secondly, is the build sheet the only way for me to extract RPO Code information? I assume yes but I'd like confirmation of that.

Also, the tech center here lists the HP block as a 350 HP, but in two other sources that suffix code is listed as a 300 HP. How can I find out for sure? Also, I'd like to findout camshaft lift and duration, compression, confirm the rear axle ratio and just more specifics..... any ideas how I can find that info easily? Danka all!!!

Build sheets were placed on the fuel tanks on all 67 and newer Corvettes. Reports indicate that carbon copies were often folded and stuffed between the tach and speedo gauges or in the springs under one of the seats.
Gary

 

[craig32]

I'd like to findout camshaft lift and duration, compression, confirm the rear axle ratio and just more specifics..... any ideas how I can find that info easily?

Danka all!!!

The easy way to find the rear axle ratio is to take off the cover and count the teeth on the ring and pinion and divide it out. Lift and duration of cam might be tough without taking it out and measuring it with a micrometer. Not sure if you could accurately measure from the rocker arms as hydro lifters might deflate. Good luck!

Craig

 

[68Roadster]

HP = 327cid 350HP, Manual, AC, PS

Build sheet is on the gas tank
Can't help ya on the cam, haven't spotted a buildsheet next to my tach or in the seat springs

Code on splitline on rear end hsg will tell ya the ratio, provided no one has been in there messing with it:
AK 3.36 AS 3.70
AL Posi 3.08 AT Posi 3.08 HD
AM Posi 3.36 AU Posi 3.36 HD
AN Posi 3.55 AV Posi 3.08
AO Posi 3.70 AW Posi 3.08 HD
AP Posi 4.11

Hope this helps some

 

[chevyaddict]

The easy way to find the rear axle ratio is to take off the cover and count the teeth on the ring and pinion and divide it out. Lift and duration of cam might be tough without taking it out and measuring it with a micrometer. Not sure if you could accurately measure from the rocker arms as hydro lifters might deflate. Good luck!

Craig

Craig you silly; OF COURSE I know how to do THAT... but I'm trying to figure out an easier way!! ha ha. Thanks though.

 

[chevyaddict]

HP = 327cid 350HP, Manual, AC, PS

Build sheet is on the gas tank
Can't help ya on the cam, haven't spotted a buildsheet next to my tach or in the seat springs

Code on splitline on rear end hsg will tell ya the ratio, provided no one has been in there messing with it:
AK 3.36 AS 3.70
AL Posi 3.08 AT Posi 3.08 HD
AM Posi 3.36 AU Posi 3.36 HD
AN Posi 3.55 AV Posi 3.08
AO Posi 3.70 AW Posi 3.08 HD
AP Posi 4.11

Hope this helps some

Cool!! I'll crawl under there and check that out. Car hasn't been tinkered with too much; I bought it from someone who owned it since 72! ha ha
Thanks!

 

[68Roadster]

Cool!! I'll crawl under there and check that out. Car hasn't been tinkered with too much; I bought it from someone who owned it since 72! ha ha
Thanks!

Here's the code on my housing...

 

[chevyaddict]

Awesome!!! Thanks!! This is great!

 

[Whiplash]

Awesome!!! Thanks!! This is great!

Not sure how accurate this site is but it appears that they've done some research. Good luck..

http://www.geocities.com/MotorCity/Downs/3000/cmspec.html

Whiplash

 

[chevyaddict]

Thanks.... I had found that website and noticed some of the discrepancies there; that is why I originally posted my questions!! ha ha ha
Dawn

 

[Art Jett]

I looked on my dirrerential and the stamping on mine dosen't look anything like the picture from 68 roadster. The stamping is as follows.
OA O34 W7 E1
This is on the bottom. Is there a different stamping on the top? Hopefully not, I already have the diff. back in the car. If not, anyone have an idea which ratio I have?

 

[JohnZ]

I looked on my dirrerential and the stamping on mine dosen't look anything like the picture from 68 roadster. The stamping is as follows.
OA O34 W7 E1
This is on the bottom. Is there a different stamping on the top? Hopefully not, I already have the diff. back in the car. If not, anyone have an idea which ratio I have?

It's a 3.08 Posi, assembled February 3, 1977 at Warren, on first shift, with an Eaton Posi unit.

 

[Art Jett]

Man! you must be the guy that built the diff. to get all that info from the stamping. Didn't make sense to me. Thanks!!!!
Art

 

[76ers]

It's a 3.08 Posi, assembled February 3, 1977 at Warren, on first shift, with an Eaton Posi unit.

...By Bubba Jr, during coffee break, decaf, light on the sugar....