I was wondering how well a C3 handles in a road course type of situiation. My friend is always talking about how good his BMW 318ti handles, is the C3 really far behind it? I know it is the same suspension designed in the early 60's, but it's IRS and similar to the C4(from what i've heard). I'd be very curious as to what everyone's opinions about the C3 suspension are.

 

With some decent tires, you should kick his butt on the autoX course. Yes the suspension is 30 years old, but it worked back then, and it still works.

Just watch out for the Miata's, they are definitely fast around the cones.

 

Suspension mostly the same from 1963-1982. Design from the 50s. How well it handles depends on how much you want to spend. :lol: I don't remember seeing any comparison tests between a 2003 BMW 318 and a 1963 - 1982 Corvettes.

Best to borrow one from the BMW dealer and "wring-it-out", then you could form your own conclusion. To be fair, your 79 should have new bushings, shocks, ball joints, new idler arm, and a steering rebuild.

 

I'm installing one of these in my 72. Should help:)
http://p-s-t.com/fekgmpgs.html

 

While the design is from the 60s the laws of physics have not changed !
The main advantage C4 has is the larger wheels & better tires.
To compare see R&T.

77 FE-7 From my website:

A good standard of handling is the Road & Track slalom course.
77 sets new record in 77 with 63.6 mph. "hampered by stock air pressures"

Surprisingly, R & T did not try or publish performance with increased air pressure.
They were aware stock air pressures were meant to keep the less astute out of the weeds.

For reference, Mario Andretti turned 63.4 in a 1999 Corvette.

PS Several of us on this forum know.

:cool:

 

You'll kick his butt on a road course. Autocross he may beat you depending on how tight it is.

 

IMHO, a properly set up C3 (poly all around, correctly sized stabars, smart struts, 17" wheels, new design brake pads and good tires) that is driven by someone who knows what they are doing can be very competitive with a showroom C5 driven by a near novice. C5s have the advantages of better suspension geometry, computer assist in major areas (ABS, SRC), bigger brakes, and much bigger and better tires not to mention superior powerplant.

The article described C3 vs 99 on one course. Locally, C3s do better in longer courses with sweeping turns and do more poorly in short courses with real tight turns. My guess is that with Mario driving, the 99 would win 8 out of 10 randomly selected courses. Ditto Markus on this point.


[Modified by flynhi, 1:07 PM 5/4/2003]


[Modified by flynhi, 1:08 PM 5/4/2003]

 

A BMW doesn't have a chance. From Solo II (aka auto-cross) to solo I (high speed road course) the C3 corvette has a serious advantage in it's suspension. Some of the main factors is the way a leaf spring is transverse and bolted to the differential...this is how all formula cars are made...I think the BMW is chassis mounted coil spring suspension. The C3 is also a well balanced 48/51 while I believe the BMW is front heavy something like 60/40 and will push around the corners.

In my opinion the C3 suspension is an awesome design and all other stock vehicles don't even come close.

The only place that a C3 suffers is on a high speed course where the poor aerodynamics comes into play...the only fix is to smooth out the lines, i.e. turn it into a C4.

 

Don't knock BMW's on either handling or design...in the right circumstances they will blow a C3 away. The BMW club I belong to is heavily into driving events, schools and track days. My 71 vert. is very competitive on tracks like PIR where there are few slow speed corners and horsepower helps. A tight, slow speed autocross is another matter. BMWs are well engineered with great weight distribution, good brakes and stiff chassis design which all adds up to good handling. A C3 can be competitive with bigger tires, composite spring, adjustable struts etc. but the biggest obstacle is that a stock C3 frame is flimsy compared to a modern chassis. On smooth, large courses it is not as big a concern, but in tight, bump circuits, you end up feeling and fighting flex.

 

I guess our 11.8" rotors with quad-piston calipers and near 50/50 weight balance don't count for anything. :confused:

Our cars use the "revolutionary" front-midship design that Nissan is touting as the greatest thing since sliced bread. They've been using it since 63.

When we were using a multi-link independent rear suspension, BMW was using everyone's favorite: swing-arm! That's the style that got Corvair in the spotlight.

So yes, a 2003 BMW has more technology embedded into it than our cars do, but I've done my fair share of putting those guys in the dust.

Driving a car fast is 50% driver, 50% car. My C3 handles awesome. In the hills, I've pulled over quite a few cars. 300ZX, a number of BMWs, newer Corvettes, etc...

Driving my car is an absolute blast after all the suspension work I've done. I don't regret it one bit! When I put my smart struts in, it should be even better. The only thing holding me back after that is rims/tires, and those will most definitely make my car hit the twisties as well as almost any modern sports car.

-Steve

 

Wow, I can do a direct comparison here since I drove both yesterday. Upgraded C3 BB vs stock 318i. The BMW is a much lighter car in my case but runs a lot less rubber on the ground. The BMW feels very confident in a corner and is far more forgiving while hitting bumps in a hard corner over the vette. Turn in feels a bit more precise but that may be due to the rack and pinion steering and quicker steering ratio. As far as pure grip in a corner I think the 73 is better but the 73's meats are also larger and of a stickier compound so if your just comparing suspension to suspension it would be hard to call. The C3's brakes are on of its best assets, how many cars today are even running 4 piston fixed calipers, not very many, and the rotors are of very good size. Now if I had to choose a car to run on a short tight course I'd probably take the BMW, albeit with some stickier meats. on a course with any sort of a staight or a long sweeping curve give me the vette. Keep in mind that stock to stock the BMW is head and shoulders above how my car was stock, but with the improvements that are in my sig I prefer the vette when playing in the twisties. The C3 is a good handling platform albeit not great (too much chassis flex with the stock frame setup), the C4 was a good improvement on the C3 setup (drive an early Z-51 C4 and you can tell), and the C5 is even better yet. The parts are out there to make them handle very well.

:cheers:
Pat Kunz

 

I am not knocking C3s, heck, I own one! But I also do not have to run down other makes to appreciate my Corvette. In terms of design etc. there is no one best way to make a great handling car. Look at all the differences in suspensions between Porsche, BMW, Chevrolet, Ferrari etc. As important as the basic design is the execution of it and what can be learned from suspension engineering evolution. It is hard to overcome time. New vehicles have 40+ years on the basic C3 platform. If GM got it so right, why did they change to the C4 and C5? Why do vendors like VBP and others offer so many modifications or enhancements? And to the point made by several in this post, the driver's ability/background is a huge factor in any competitive situation. In our Corvette club slaloms, I have run my 71BB against 2003 Z06s and waxed them! It is not because my car is superior, nor because I a great driver. I think the main reason I am more competitive in my C3 than many late model Corvettes is I have spend considerable time sorting the car out, find the right combination and getting confident and comfortable driving it. Just some thoughts IMHO.

 

:iagree:

I drive a Subaru SVX which is the best handling car I've ever owned. I know it's a great car but like all cars (including Vettes) it has it's shortcomings. Like a TALL automatic tranny and it could really use a diet. I doubt with the same tires it could keep up with a 318ti in the corners but it'd be close.

If I can get a C3 to handle like my SVX does I'd be excstatic because even an aniemicly motored C3 would spank my SVX in a straight line. I know because my pathetic Trans Am can ;)

I can respect any vehicle that does it's job well, from a rock-crawling CJ7 to the SR-71. My loyalties lie in excellence of execution, not in brand names or where they were made.

Just my worthless opinion, so I won't even charge you the 2 cents :lol:


[Modified by Black Snowman, 12:59 PM 5/4/2003]

 

You raised a point that I did neglect to mention in my post... well, kind of.

Different cars are better at different things.

A Corvette will do much better on a road course than at autoX or a real tight mountain road. I would not want to go up against a Miata in a parking lot. :)

I am not saying the C4 and 5 aren't better than the C3, they most definitely are, right out of the box. A lot of our problems can be corrected, but the hardest is flame flex. No one really seems to have a solid answer for that one.

-Steve

 

Does anyone know how many G's the C3 pulls on the lateral skidpad? :confused:

 

The lowest test I've seen on a stock C3 was like .73. Highest was about .82.

Upgrade suspension and tires and you should be able to hit the mid .9s no problem.

-Steve

 

In a lot of the formal competitions things that reduce frame flex are actually banned to try and keep things even. For instance in SCCA most devisions prevent you from tieing a roll cage into the frame or adding crossmembers to keep from turning the more powerful cars into corner carvers.

For the street there's nothing keeping you from doing this. However it does add weight, so it would be good to find someone with some know-how to get the most regidity for the least weight.

 

What about foam-filling the chassis?

Would that be noticeable from an inspection standpoint?

-Steve

 

Not sure what kind of foam would do the trick. It would have to harden very rigged and most of the expanding foams stay pliable.

I think it's legal to re-enforce the exisiting structure. Like welding in extra plates and braces. Just not adding new structural members. But you'd have to check the rulebooks.

I know on Merlin they welded the frame everwhere two seams got close enough to help strengthen it. I'm sure that couldn't hurt and wouldn't add much weight. The only reason they don't do it from the factory is all the labor it adds.


[Modified by Black Snowman, 4:46 PM 5/4/2003]

 

Just ask someone who owns both !



I have found that the BMW is much more controllable than the Corvette is. I have more confidence throwing that car around than I do the Corvette. ONe area that I think the C3 really suffers is in the rear suspension design. There is to much camber shift do to the fact that the upper control arm is also the drive shaft, its not a fixed element.