66 Roadster 300 HP vs 350 HP

[Lawrence S.]

Hi,
A friend of mine is considering purchasing either a 66 roadster 300 hp or a 350 hp. Both cars are restored and nicely done. Given that both cars are stock, same rear gear ratio and same transmission is there much difference one would notice, regarding performance, provided the driver was just cruising the car for enjoyment.

I own a 67 L-79 roadster and have never driven a 300 HP car so I am not much help.

Look forward to your comments.

Thanks,

Lawrence

[Dennis O.]

Re: 66 Roadster 300 HP vs 350 HP

I have owned a '67 L79 Coupe for 25 years and restored it 6 years ago. It took me a while to get it sorted out, but it now runs and drives excellently. I recently had the chance to drive a friends '67 base motor coupe. The current owner bought the car in 1971 and has maintained it meticulously for the last 41 years (he was a mechanic by trade). It now has 51,000 miles. For my purposes, there is no difference in driving them. At least for these two cars, I believe that you would need a series of runs on the dragstrip to see any difference, and maybe not even then. I really like having an L79, but in the final analysis the main difference is a couple of gauges, the air cleaner sticker and better looking valve covers on the 350 HP car.

I didn't have the desire to really get on either one that hard. I have run my car up to the redline to see if it would go there, (which it did after getting the ignition system up to snuff), but I would never run someone else's car like that. They both drove well and felt strong. Also, after this, I think I would rather have a very good original rather than a fresh restoration. Just my personal opinion.

I should add that the base motor car had 3.36 rear gears while my L79 has 3.08s, which would tend to equalize performance in general driving. The L79 coupe I bought new in June of '67 had 3.70's and as I remember was a lot faster than my current car. 45 years is a long time, however. I don't like admitting in public that my current car has wimpy 3.08 gears, but on a practical basis, I really like them.

[Joe L.]

Re: 66 Roadster 300 HP vs 350 HP

Hi,
A friend of mine is considering purchasing either a 66 roadster 300 hp or a 350 hp. Both cars are restored and nicely done. Given that both cars are stock, same rear gear ratio and same transmission is there much difference one would notice, regarding performance, provided the driver was just cruising the car for enjoyment.

I own a 67 L-79 roadster and have never driven a 300 HP car so I am not much help.

Look forward to your comments.

Thanks,

Lawrence

Lawrence-----


In my opinion, the 300 hp 327 cid (or 300 hp 350 cid) are the most pleasant to drive street engines ever installed in a Corvette. They have plenty of power and great street manners.

[Ray G.]

Re: 66 Roadster 300 HP vs 350 HP

Hello;
The 350 horsepower 327 is the most popular configuration of all time measured by customer requests over the years to
"make my engine run and sound like the 350 horse engine".
I've always thought the 350hp cam was the biggest contributor to the success.

just my .02
Ray

[Lawrence S.]

Re: 66 Roadster 300 HP vs 350 HP

Thanks guys I appreciate your input.

[Paul H.]

Re: 66 Roadster 300 HP vs 350 HP

I have owned both. The 350 horse motor definitely makes more power but it's torque curve is a little higher in the RPM band than the 300 horse. The 300 horse motor makes nice low end torque and is very satisfying when driving around as you normally would. It all depends on how you drive, but on balance, I prefer the 350 horse. All things being equal, the 350 horse will also give a slight bump up in price.

[William F.]

Re: 66 Roadster 300 HP vs 350 HP

Dennis,
Where'd you get those 3:08 gears? As far As I can tell from old Corvette ads/specs, 3:08's were offerd for L79's.Also, I've owned a 300 hp '67, a '66 L79 (for 30 yrs.) and currently own a '67 L79, and find a lot more differences between 300 hp and 350 hp engines than you do. 300 is nice and docile around town and has adequate but not anything special performqance. L79 likes to have revs kept up arond town;can't lug it; but from 3000rpm on up to 6000 redline, you'd better hold on(300 hp has to quit at 5500)! Really strong.

[Tim G.]

Re: 66 Roadster 300 HP vs 350 HP

I've had a few L79 equipped Corvettes and I love them. It is also one of the best looking engines ever put into a Corvette. Expect to pay $5,000 to $10,000 for an L79 depending on car color and other options.
Right now I have a '65 300 horse with a 350 horse cam and it's a nice combination.
The looks of the L79 alone are worth the price, those valve covers and that intake are beautiful.

[Jim C.]

Re: 66 Roadster 300 HP vs 350 HP

I've owned only two Corvettes and both have been 1966 327/300 low option cars. My first one was a coupe (VIN #16401), and my current car (VIN #27592) is a roadster. I can't say enough good things about both cars, particularly the engine. Great pickup, easy to tinker with, relaibable, they run cool, etc. I'm a big fan of the 1966 small block.

Jim C.

[James G.]

Re: 66 Roadster 300 HP vs 350 HP

I have owned both, and they are great engines. In true original form, the 350hp engine has 11:1 pop up pistons the same as the 365 and 375 fuel injection engines. But the hydraulic 350hp camshaft which I believe was one of the best ever made for all around Corvette performance. The 300hp engine is the most under rated of the two, and definitely less money to buy today, but many people pass on purchasing cars with this great engine. The 300hp engine gives great power and needs little upkeep. They are like the ''Energizer *****'', they just keep going, and going with little upkeep. Many of these engines have over 300,000 miles.

[Tony S.]

Re: 66 Roadster 300 HP vs 350 HP

I have owned both engines. I really prefer the 350 hp option. Besides running really well, it just looks better in the engine compartment. I love that aluminum intake and script valve covers. With the 300 hp engine, you have a painted intake, so whenever you get a gas leak from your carb, you get paint peel. To me, the 350 hp is the way to go.

[Duke W.]

Re: 66 Roadster 300 HP vs 350 HP

I have owned both, and they are great engines. In true original form, the 350hp engine has 11:1 pop up pistons the same as the 365 and 375 fuel injection engines. But the hydraulic 350hp camshaft which I believe was one of the best ever made for all around Corvette performance. The 300hp engine is the most under rated of the two, and definitely less money to buy today, but many people pass on purchasing cars with this great engine. The 300hp engine gives great power and needs little upkeep. They are like the ''Energizer *****'', they just keep going, and going with little upkeep. Many of these engines have over 300,000 miles.

It's easy to convert an OE 300 HP engine into a Special 300 HP engine with the McCagh Special Camshaft. Head massaging in conjuction with the cam will maintain the smooth 500 RPM idle and stump pulling low end torque while making L-79 like top end power and revs with all the OE reliability, longevity, and ease of mainteance... all in a package that looks absolutely original on the outside that will easily pass a PV.

Duke

[James G.]

Re: 66 Roadster 300 HP vs 350 HP

It's easy to convert an OE 300 HP engine into a Special 300 HP engine with the McCagh Special Camshaft. Head massaging in conjuction with the cam will maintain the smooth 500 RPM idle and stump pulling low end torque while making L-79 like top end power and revs with all the OE reliability, longevity, and ease of mainteance... all in a package that looks absolutely original on the outside that will easily pass a PV.

Duke

As Dick Guldstrand says, ''YOU AIN'T CHEATIN UNTIL YOUR CAUGHT'' I love American ingenuity. That's how we won WW2.

[Duke W.]

Re: 66 Roadster 300 HP vs 350 HP

I LOVE "cheater motors"!

Life is a game - like blackjack in Las Vegas. You learn the "rules" and figure out a way to tilt the odds in your favor.

That's why I've been a successful engine system engineer and private investor (never had a "down" year) for the last 20 years.

Duke

[Michael M.]

Re: 66 Roadster 300 HP vs 350 HP

It's easy to convert an OE 300 HP engine into a Special 300 HP engine with the McCagh Special Camshaft. Head massaging in conjuction with the cam will maintain the smooth 500 RPM idle and stump pulling low end torque while making L-79 like top end power and revs with all the OE reliability, longevity, and ease of mainteance... all in a package that looks absolutely original on the outside that will easily pass a PV. Duke

So, it's a nice cam when rebuilding an L79 as well, correct? The same top end power and a little (or a lot) more low end torque. And a smoother idle too. But maybe not pass the PV? No lumpy idle. Otherwise, no downside right? Sounds like a nice way to go if you can live without the PV. How would you handle the CR on a rebuild like that? Go higher like the L79 or lower like the 300hp engine. Maybe there is a better cam for the L79 rebuild?