Horsepower ratings clash with stock carb

[Big_Al]

Hi everyone. I'm new to this group and haven't seen any letters or questions’ pertaining to my question, so I hope this hasn’t been answered before.
I purchased a 1969 RS Camaro from a family member back in '71. I've known this car since day one and know for a fact that nothing has been changed, but it has a Rochester 2GV carb on a 350 block with the air cleaner sticker stating 255hp. All the research I've been able to uncover (including this site) states that a 255hp 350 block has a Quadrajet 4MV carb and the 2GV carb is rated at 250hp. The engine came from Tonawanda N.Y. and I'm wondering if it is just a simple case of applying the wrong sticker at the factory?
No big deal really but it has kept me wondering for many years.

Thanks,
Big_Al

[Stingr69]

Get the numbers off the top of the engine block directly in front of the passenger side cylinder head. The engine suffix code was stamped there. The date code and suffix will shed some light on what you have going on in there.

The 4-barrell LM-1 was discontinued around January 69 and the 2 barrell 250 HP engine was used after that. Maybe you got caught up in that?

-Mark.

[Big_Al]

Thanks for the quick response Stingr69. Will check number soon.

[Big_Al]

I finally got a moment to myself to check out the engine pad numbers: T0409HD. If I'm correct in my interpretation, it was made in Tonawanda, NY, April 9th 1969 and is a 250HP 350 block.

I wonder, were LM1 350's still being produced at that time? I was told the LM1's were gone by January of '69???

I'm not sure if this factory wrong sticker will hurt my car's chances at some shows. Some years ago at a Camaro show, a judge took one look at the sticker and informed me either it was wrong or the air cleaner, 2GV carb and intake were wrong. Since this car is all original, I'd hate to remove the perfect condition, original air cleaner sticker and replace it with the correct one. Maybe I'm making too big of a deal with this and should just get the correct sticker.

Thoughts anyone?

[rich69rs]

Quoting from the followiing CRG link / research report:  http://www.camaros.org/carb.shtml#roch

The lower-performance 327/210hp, 307/200, and 350/250 engines received the Rochester "Dualjet" (2GV) two-barrel carburetor. Rated at 500 CFM, this larger carburetor was necessary for the larger displacements of the small V8 engines. It too gave ample power, while achieving good gas mileage.
There were actually two versions of the 2GV. The SAE 1-1/4" bore version was used on Camaros 327 and 307 engines. It can be easily identified by the fuel line inlet being located on the side of the carburetor. The larger SAE 1-1/2" bore version was used on 69 Camaros with the L65 350 engine. The fuel line inlet is located on the front of the installed carburetor.

The 2GV models specified for cars with air conditioning had a "hot idle compensator" feature. When high underhood temperatures occurred during idling, the compensator supplied additional air to offset excessive fuel vaporization.

Your carb should have the 1-1/2" diameter throttle bores and easily identified from the fuel line entering the front of the carb.  2GV breaks down as 2 = 2Bbl carb, GV = divorced choke.  Rochester also made a 2 Bbl carb designated as model 2GC; which had a thermostatic choke mounted on the carb body.  Not used on 1st gen Camaros.

Also, the 500 cfm rating applied to the SAE 1-1/2" bore carb.  The SAE 1-1/4" carb flows closer to 400 cfm and begins to die between 3500 and 4000 rpm.

[Big_Al]

A lot of good info, thanks for pointing me in the right direction, rich69rs.
 
It does have the front inlet, 1-1/2" bore carb, which is correct for my engine according to the engine pad numbers. Everything is original (family member bought it new) so I guess GM still had some 255hp air cleaner stickers laying around and mistakenly slapped one on my 250hp 350.

What? GM made mistakes? Built on a Monday morning or late Friday?
Maybe I should just get the correct sticker.

[Stingr69]

Factory mistake or not, I might be inclined to get a new sticker if I was in your shoes.

-Mark.

[KurtS]

Who knows how that sticker got on there. I suspect it wasn't at the factory.
I'd replace it.

[Big_Al]

Thanks for your comments everyone.

I plan to replace it although I know with almost certainty it is the original sticker.
Unless someone from the dealership put it on, it was, according to the original owner (my brother) what the car came with when he bought it new. He and his wife ordered it to their specifications (a gift to her) and kept it stock except for aftermarket chrome mud flaps and a CB radio. I'm grateful he was gentle with it, using a clamp mount antenna and routing the wires through existing holes and opened panels along the way instead of just drilling everything! I purchased it from him in '71 with 35,000mi.


Al

[Oregonjam]

Honestly, if you are not sure about what to do, why not replace the air cleaner cover with a NOS/repro and apply the 'correct' sticker to that. Then hang the original in the garage. You can always switch it back if you want.

If you peel the sticker off it is gone forever....

Cheers,
John

[Big_Al]

What a great idea, that's what I'll do! 

Thanks John!


 Al