C1-Fan

Greetings from Texas. I have a 1960 Corvette (black with silver coves) with a numbers matching 283 engine with 2 four-barrel carbs and 245 HP. Can anyone tell me the differences in a 1960 Corvette with:

1. 283 / 2x4 barrel carbs with 245 HP
2. 283 / 2x4 barrel carbs with 270 HP?

I have heard that the differences include a different cam and a different radiator. Is this accurate? Are there any other differences that you may know about?

I'm planning to have the the motor in my Corvette rebuilt and I am considering making it a 270 HP Car. Any wisdom / insights would be greatly appreciated.

jim lockwood

The tach face for the 270 HP engine has a higher redline.

The generator pulley is likely larger on the 270 engine.
Edit: The above statement is incorrect. 270 HP and 245 HP engines both use 1102043 generators with 3-5/8" offset pulley

The carburetors are almost certainly calibrated differently.

If you install the correct "top tank radiator", I believe you have to also replace the radiator support.

Frankie the Fink

First and foremost the 270hp cars have solid lifters and the legendary Duntov 097 camshaft.

The carbs are set up for the more aggressive camshaft characteristics.

1snake

The hood is also different in order to clear the top tank reservoir.

jim lockwood

I was under the impression that the hood difference was between '60 and prior years, not between 1960 cars with brass and aluminum radiators. Not true?

1snake

There was a change in hoods during the 1960 model year. Here's a commonly posted pic. Only the later hoods had the clearance for the top tank and the required different radiator support.
40+ years ago, I talked at length with Noland Adams about the issues with the "new" aluminum radiator and how GM dealt with the issues and shortages of them.

alblosser

I thught the 270 hp engines also had a higher compression ratio.

MikeM

Only the FI engine.

jim lockwood

This looks to be a case of the factory simply using up left over '59 hood stock opportunistically on cars with brass radiators.

The current '58 - '60 judging guide sez this about the re-designed hood:

"This hood was also used for most low horsepower 1960 brass radiator equipped cars."

So the hood is essential for cars with top tank radiators but was also used on brass radiator cars.

Frankie the Fink

As to the wisdom of "building" a 270hp car.....

I had an original 270hp car and they are a hoot to drive, and the solid lifter sound is unmistakable.

Would I go to the trouble to try to build one, cloned from an original 245hp engine. No. It would be expensive, they require a bit more maintenance and, depending on what the OP means by "numbers matching", if there is a stamp pad engine suffix, it won't be fooling anybody.

There is nothing wrong with tooling around in an original 245hp car with dual quads,

jim lockwood

If that's a reference to periodically adjusting valve lash, it doesn't match my experience.

In 41 years of maintaining my '60 290 HP car, I bet I've adjusted the valve lash at most three times. The last time, in 2013, was because I had R&R-ed one head and there was simply no choice but to adjust the lash.

The amount of maintenance my '60 solid lifter engine requires is on par with that required by the hydraulic lifter engine in my '63.

Frankie the Fink

Don’t really want to debate it.

Still, my opinion for the OP is to restore the car to factory 245hp specs.

MikeM

PS. I'd change the cam to the 270. It'll make a whole different driving experience over what you have now. Not a whole lot of power increase, just different feel. Enjoy the feel and sound of a Corvette instead of a Bel Air.

I wouldn't bet it would be necessary to do anything to your carburetors to make it work with the different camshaft. Bump the initial timing up 4-5 degrees.

1snake

I'm aware of what the Judging Guide says and disagree using the term "most". That's not been my experience over the years. If they were using left over 59 hoods, they must have had one he!! of a stock pile of them. Years ago I had the opportunity to examine a 1 owner 230HP 1960. It had the early style hood, brass rad. etc. and it was a late March car. The most amazing thing about that car was it had never been wrecked and had 100% of its original Cascade Green paint.

To the O.P. - If you're wanting to create the look of the 270HP car, at a minimum, you'll need a top tank rad. and core support and possibly a hood. You may want to price that rad.at DeWitt's. The price alone may scare you. The 270HP engine is a sweet driver. Here's a pic. of mine. I've had it for 46 years and it was my daily driver for the fist 10 years. It never leaked a drop, even in the rainy Pacific Northwest and being parked outside. Only adjusted the lifters once in those 10 years. Then I did a complete body off restoration and it's lived a charmed life ever since.

jim lockwood

That's interesting and I'd like to learn more. Do you mind sharing your data?