C2 vs. C3 Handling

[Dan Pepper]

I recently added a '69 350/350 4spd coupe to park in the garage next to the familiy's '66 L36 4spd coupe. Not having experience driving Corvettes other than these two, I'm surprised by the difference in handling between the cars. The C3 has had all new bushings, shocks and a TRW rear spring installed. The car handles like a go-cart on rails and feels like it weighs only 2000 lbs. The ride is uber firm, and the steering is down right twitchy at speed and you have to be paying attention all the time.

The '66 Big block is a 53k original mile car that has never had any suspension work done other than a new set of Gabrial shocks at some point in it's life. This is a fun, tight car to drive, but feels so much heavier and a bit looser than the small block C3. I do have crappy "S" rated all season tires on the C2, and older Goodyear Eagles on the C3, but the difference is still very pronounced - beyond tires.

Can I expect to make the C2 (my favorite ride because of the stying and grunt factor) handle like the C3? I love the 427 and can live with the characteristics it imparts, but I'd like to improve it if I can. Will a new set of bushings and rubber parts do this for me?

[Duke W.]

Re: C2 vs. C3 Handling

At least 80 maybe 90 percent of the handling equation is tires.

Power steering cars can feel like they "handle" better just because you can jocky them around with one hand.

Small blocks probably have a slight edge on handling because they are a bit
better balanced, but tires anti-roll bars (and their bushings), and alignment make a big difference.

It's all in the details, but tires and alignment are probably a good starting point.

Duke

[Mark #28455]

Re: C2 vs. C3 Handling

Do both cars have the base suspension or does the '69 have the F41 suspension? Also look at where the tie rods attach to the spindles, the '69 may have them attached in the "fast" steering position. If your car has power steering, they must be attached in the fast position. You can move the '66 arms to the fast position, but forget about trying to maneuver the car at low speed (like parallel parking).

[Rich G.]

Re: C2 vs. C3 Handling

Interesting. I have a 66 small block and a 68 big block. I think the 66 handles better. A friend has a number of C2's, BB and SB and he would tell you that the SB handle better. I have modern radials on the 66 and repro Red Lines on the 68. The 68 has power steering and the 66 doesn't, but the 68 seems to "wander" more on rough roads.

I had beed driving the 66 for about 2 years when I got the 68. After driving the 68, when I got back into the 66, I thought I was in an MGB, except for the noise and the acceleration!

Rich Giannotti

[Dan Pepper]

Re: C2 vs. C3 Handling

Both cars are power steering cars (the '66 BB also has PB, unlike the '69), so both are set for "fast" steering.

I don't think the '69 has F41, but it does have a TRW fiberglass rear spring that, I'm sure, stiffens up the ride substatially. The car still has the tank sticker attached, but it's covered in dirt. The shark does have more of a tendancy to "wander" as mentioned by another shark owner earlier in this thread, but I think that's only because it feels more positive/lighter. That is to say, a twitch of the wheel may make you end up in the ditch.

[Mike Cobine]

Re: C2 vs. C3 Handling

There are a host of things that could be the difference.

Fiberglass springs react differently than steel, so putting a fiberglass spring on a car originally equipt with a steel spring means you have to reconfigure the shocks also. A stock off-the-shelve Corvette shock will NOT work. The shocks have to be set to work with the fiberglass spring. So call up your shock manufacturer and ask about having yours recalibrated. Since TRW makes many rates, you could be stiffer on the rear than the stock steel, which would induce oversteer.

The big block will have more natural understeer, even with the rear sway bar. One advantage of the big block is that you can induce power oversteer more easily than with a small block in a corner. However, the weight makes understeer more pronounced at times you are not into the power. As such, you can jump from understeer to oversteer and back, which can give an unsettling feeling to one not used to such. However, on the skinny tires that a '66 has, you can induce power understeer also by simply driving straight before turning.

The weight also slows the response. The advertised 51/49 percent front to rear weight distribution can make the front sluggish to turn. This is due to things like polar moments and such, i.e., hanging weights at the ends of a pole versus placing the weight at the center. The '69 is closer to 50/50 and has less weight at the ends so it will react faster.

Comparing a car with new suspension bushings to old worn ones is like comparing a new Corvette to an old Corvette - foolish to even attempt such.

Tires - as Duke said, tires can be 90% of what you feel. New tires versus old, one manufacturer versus another, one size versus another size, one tread pattern versus another. If you don't have the same tires on both, then of course there will be differences and there can be great differences. Why else would the tire industry be such a huge industry if you simply could put any tire on and they would act the same?

Simply put, tires have usually two things in common - they are usually black and they usually roll. After that, everything is different.

As others have mentioned, alignment plays a large function in how a car handles. One the race car at tracks like Sebring, I ran about a degree toe-OUT. Yes, out, not in. This made the car very darty in the corners but it sped up the turning. To drive one on the street like that would to be virtually out of control and to scrub the tires bald in no time.

Returning from Daytona with a blown engine, I went to a local autocross after dropping in a new engine to sort things out. My times were so slow, you would have thought it was a pickup truck on the course. The reason? The alignment was set for staying steady at 180 mph and I could barely get turned on the autocross course.

So either accept that they handle differently, or start changing and correcting items to make them handle more-or-less the same.

Frankly, I've never driven two Corvettes that ever handled the same. Every one was like an entirely different car.

[Dan Pepper]

Re: C2 vs. C3 Handling

This is all interesting and useful info. I think the best course of action is to install new rubber - both bushings and tires - under the '66 big block. The tires I have on the car now were a compromise when I bought them. I separated a belt (thank you Firestone) on a road trip to the 2001 bend regional meet. Had to stop at the local tire store in Central Oregon and buy what they had to fit: just all season S rated radials. It was the only way i could go at the time.

As mentioned, I prefer the lil'bit softer handling of the '66 to the '69. I think the TRW spring on the '69 is a much firmer-than stock spring, and it also has newer Delco gas charged shocks to match the spring set-up - so hence the oversteer. The understeer on the '66 big block car, I'm sure, is exacerbated by crappy tires and softer (stock 9-leaf) spring in the rear. Regardless, it's the first 1/8th mile in a straight line that makes my grin the widest.

[Jim T.]

Re: C2 vs. C3 Handling

My C3 is set up with a little more suspension changes than stock. Put the Vette Brakes Performance Suspension package on. This includes changing out the front control arms and installing transverse front spring, all poly bushings, and much larger sway bar. Rear has 360# fiberglass spring, poly bushed adjustable rear struts, and rear sway bar with poly bushings. Carerra adjustable shocks front and rear. This C3 handles, it will swap interstate lanes better than my 85 and my 96, and like you say handles like it is on rails. I have been driving it for about 10 years and still like it. When I want I can change it back to its original configuration. One piece I have yet to install is the bar that goes between the upper control arms. Have to get the braces welded to attachment pieces.