C4 vs. C5 Suspension?

[Last Ride]

Okay, not really sure where to post this, so I will try here and the C4 Tech forum. Say a guy wants to graft a late-model Corvette Suspension setup to a C3. I have my choice of either a C4 suspension setup (it will also accept any aftermarket or performance suspension setup for the C4) or a C5 setup (same applies). The C5 setup while not really much more expensive, requires cutting to the rear fiberglass on the car. Which setup would you choose and why? Would the C5 setup really be that much better when the C4 setup would already be night and day from the old C3 setup? Would the C4 and C5 setups ride about the same? Thanks for the help!

 

[c4c5specialist]

Hi there,
First, what are you attempting to acheive????
A little background on c4, is that there were constant changes to suspension geometry throughout the c4 production, so depending on what year suspension you get, this will also depend on how it will react to power added to it, how it will handle, and the like.
Just remember, that ZR1 had a tough time planting tires because of the power subjected to the chassis.
c5 suspension systems have NOT gone through this type of geometry changes, due to simply advances in computer aided design, and fabrications. The only things that have been changed is the spring rates, sway bars and shocks, not the actual geometry of movement itself.
Frame strength also plays a very important role in the way an add on suspension works. One of the reasons that c5 rides so well, is that the frame is so strong, that the spring rates could be softened without losing handling characteristics.
So, with that in mind, as long as your frame is strong enough, I would go c5, however, EVERYTHING will depend on how strong your frame actually is.
Allthebest, c4c5

 

[Last Ride]

Thanks, C4C5. What I am trying to achieve is a car that looks like a classic but rides and handles like a more modern car. The frame I am looking at is modelled after the C3 frames (obviously since it is going under a C3), but I plan on adding a 4-point rollbar to stiffen it up a bit. Would I gain much by welding the frame and filling it with foam, other than weight? The whole idea behind this is so that my wife feels more comfortable driving the car. She thinks that it is clumsy and takes too much effort to drive as it sits right now. The car would need to handle around 500 horsepower give or take. I have seen a few people doing C4 conversions, but only one doing conversions for the C5.

Bryan

 

[c4c5specialist]

HI there,
Well, as for the frame mods, I do not know exactly the best way to strengthen the frames on c3. I would talk to a chassis builder or someone whom races c3 to get a more concise idea of what is involved.
As for the suspension, I can only speak from my experience. I worked on the Miss Mako concept car. It is a 64 convertible and when researching my suspension changes, I explored alot of different options. Of course, my powertrain was the first consideration, as if I was to have a big block, I would need a heavier suspension, due to weight. If I was small block, I can change a few things, and make it ride and handle better.
I settled on a 350 electronic fuel injected engine, with a 700R4 automatic overdrive. So with that, I also knew what suspension I would use. Cost and ride and handling all were a consideration.
I settled on the Vette brakes and products suspension system, with Sensatrac shocks from Monroe.
The suspension system gave me the infinite adjustability of fiberglass epoxy leaf springs front and rear, but the shocks gave me a smoother ride than the KYB shocks that came with the package.
I was only putting about 302 horse to the rear wheels, so this worked well since the car sat higher a bit, rode well, and could be driven all day.
With that, please understand this is not an endorsement, just the facts when I was confronted with my c2 project.
Just a sidebar, the tires also have alot to do with how the car rides, so that also must be taken into consideration.
If you have further questions, please let me know.

 

[tipcapman]

Not sure why anyone would want to do this mod, but as a start you can refer to Hot Rod Magazine May 2003. They grafted a C5 front and C4 rear suspension onto a 1963 Corvette.

Actually, the cost of the mod was surprisingly low, although it did not include all completion on the vehicle.

Might be better to buy a completely engineered system.... known as a "C5". LOL

Regards..

Len

 

[Last Ride]

Not sure why anyone would want to do this mod, but as a start you can refer to Hot Rod Magazine May 2003. They grafted a C5 front and C4 rear suspension onto a 1963 Corvette.

Actually, the cost of the mod was surprisingly low, although it did not include all completion on the vehicle.

Might be better to buy a completely engineered system.... known as a "C5". LOL

Regards..

Len

Len--
First of all, welcome to ! Secondly, can you tell me how a 1997 Corvette differs cosmetically from a 2003? Or the difference of a 1998 convertible to a convertible built in 2001? I couldn't tell either if they were all wearing the same wheels. I think the C3 generation has more character than the C5 or even the C4. Just a personal opinion. To me, the C3's radical design represents an era that seems to be past in the auto industry. A car that looks as impractical as it actually is! My wife would love a C5. I wouldn't mind one if it looked like a C3. See where I'm going with this? But anyway, I know it's not cheap, but I was just curious as to the advantages a C5 suspension would have over a C4 given they were both on the same vehicle.

Bryan

 

[Last Ride]

HI there,
Well, as for the frame mods, I do not know exactly the best way to strengthen the frames on c3. I would talk to a chassis builder or someone whom races c3 to get a more concise idea of what is involved.
As for the suspension, I can only speak from my experience. I worked on the Miss Mako concept car. It is a 64 convertible and when researching my suspension changes, I explored alot of different options. Of course, my powertrain was the first consideration, as if I was to have a big block, I would need a heavier suspension, due to weight. If I was small block, I can change a few things, and make it ride and handle better.
I settled on a 350 electronic fuel injected engine, with a 700R4 automatic overdrive. So with that, I also knew what suspension I would use. Cost and ride and handling all were a consideration.
I settled on the Vette brakes and products suspension system, with Sensatrac shocks from Monroe.
The suspension system gave me the infinite adjustability of fiberglass epoxy leaf springs front and rear, but the shocks gave me a smoother ride than the KYB shocks that came with the package.
I was only putting about 302 horse to the rear wheels, so this worked well since the car sat higher a bit, rode well, and could be driven all day.
With that, please understand this is not an endorsement, just the facts when I was confronted with my c2 project.
Just a sidebar, the tires also have alot to do with how the car rides, so that also must be taken into consideration.
If you have further questions, please let me know.

C4C5--
The Vette Brakes Performance Plus system is sitting in my garage as we speak. Also sitting in my garage is a Steeroids rack and pinion conversion kit. Both are ready to go on the car. I was just considering my options, and grafting a C4 or C5 suspension onto my car would not cost terribly more than what I would have in upgrading the stock stuff when I am done. Like I said, at most, I am going to be looking for 500 horsepower, so maybe the later model suspensions wouldn't be worth the trouble...

Bryan

 

[81LT4]

Len--
First of all, welcome to ! Secondly, can you tell me how a 1997 Corvette differs cosmetically from a 2003? Or the difference of a 1998 convertible to a convertible built in 2001? I couldn't tell either if they were all wearing the same wheels. I think the C3 generation has more character than the C5 or even the C4. Just a personal opinion. To me, the C3's radical design represents an era that seems to be past in the auto industry. A car that looks as impractical as it actually is! My wife would love a C5. I wouldn't mind one if it looked like a C3. See where I'm going with this? But anyway, I know it's not cheap, but I was just curious as to the advantages a C5 suspension would have over a C4 given they were both on the same vehicle.

Bryan

MAN, I'M WITH YOU A 100%,

 

[tipcapman]

My wife would love a C5. I wouldn't mind one if it looked like a C3. See where I'm going with this? But anyway, I know it's not cheap, but I was just curious as to the advantages a C5 suspension would have over a C4 given they were both on the same vehicle.

If you wife would love a C5, and since you love her, buy her the C5!!!!

There are two sides to every coin... I think it is admirable that GM essentially "got it right" with the C5 out of the box... there have been considerable and numerous mechanical improvements during the run, but yes, they are difficult to tell apart. For the guys who bought early in the run, they probably see less depreciation, and can actually upgrade with things like OEM wheels and exhaust, heck a HUD installation isn't even that difficult!

For the guys who bought later models, granted they look very similar to the first ones off the line, but on the one hand they have different colors and options, and on the other I think they can be proud to know that it was a great design from day one, and didn't need to be developed after it was out the door.

As for grafting the different generations of suspensions on that 1963 model.... as you know, the C5 has a transaxle, integral with the rear suspension, which makes that transplant that much more problematic.

Let me reiterate... I admire your energy and vision, but this sounds impractical to me. If you want a car that has the mechanicals of the C5 with the looks of a C3, why not take a C5, strip the body and graft on a C3? Granted, it would require a massive rework, but at least that is just body work.

The foundation of the C5 is it's advanced structure... hydroformed frame rails, cast aluminum front and rear subframes, cast magnesium dash support, composite floor pan, deep setel tunnel, etc. It is all designed to work as a system, providing an extremely stiff substructure for the gorgeous front and rear suspensions.

The analogy, although maybe a poor one, is to build a beautiful house on a shaky foundation.

Thanks for the welcome, and let us know how this comes out!!!!

Regards...

Len

 

[tipcapman]

My wife would love a C5. I wouldn't mind one if it looked like a C3. See where I'm going with this? But anyway, I know it's not cheap, but I was just curious as to the advantages a C5 suspension would have over a C4 given they were both on the same vehicle.

If you wife would love a C5, and since you love her, buy her the C5!!!!

There are two sides to every coin... I think it is admirable that GM essentially "got it right" with the C5 out of the box... there have been considerable and numerous mechanical improvements during the run, but yes, they are difficult to tell apart. For the guys who bought early in the run, they probably see less depreciation, and can actually upgrade with things like OEM wheels and exhaust, heck a HUD installation isn't even that difficult!

For the guys who bought later models, granted they look very similar to the first ones off the line, but on the one hand they have different colors and options, and on the other I think they can be proud to know that it was a great design from day one, and didn't need to be developed after it was out the door.

As for grafting the different generations of suspensions on that 1963 model.... as you know, the C5 has a transaxle, integral with the rear suspension, which makes that transplant that much more problematic.

Let me reiterate... I admire your energy and vision, but this sounds impractical to me. If you want a car that has the mechanicals of the C5 with the looks of a C3, why not take a C5, strip the body and graft on a C3? Granted, it would require a massive rework, but at least that is just body work.

The foundation of the C5 is it's advanced structure... hydroformed frame rails, cast aluminum front and rear subframes, cast magnesium dash support, composite floor pan, deep setel tunnel, etc. It is all designed to work as a system, providing an extremely stiff substructure for the gorgeous front and rear suspensions.

The analogy, although maybe a poor one, is to build a beautiful house on a shaky foundation.

Thanks for the welcome, and let us know how this comes out!!!!

Regards...

Len

 

[bluecoupe]

Look at these for the rear of your C3:

http://www.corvettefaq.com/c3/6link/index.html

http://www.greenwoodcorvettes.com/StreetDaytona.html

 

[bluecoupe]

http://www.greenwoodcorvettes.com/Street Cars/GTO/suspension5 link.jpg

 

[richscorvettes]

Bryan,

I wrestled with the same question when researching the various suspension options for our 62. I have a 67 with the Vette Brakes Performance Plus package and, for the money and effort involved, it is a nice package. But, I was looking to do something different especially since they don't have a similar package for a C1. I also had a C5 at the time and was definitely leaning in that direction for the suspension on the 62 project.

After looking at what was involved in fitting the rear trans layout I decided to go the C4 route using the suspension from a 95. The changes to the body necessary to use the C5 setup on that car involved modifying the spare tire well as well as the gas tank area. The tire well was not a problem but there are only so many places for the tank and I didn't want to start making special dual tanks like the C5 uses. Also, the balance of the car (with the aluminum LS6 engine) wouldn't have been noticeably improved so, for the extra effort involved, it didn't seem worth it. That might be a different story though with a cast iron block.

I had Paul Newman (Car Creations) do the mods to the chassis itself and we did the rest including welding all the chassis seams to strengthen the frame. The C1 chassis is actually very stiff especially with the I beam "X" member. Going this route is much more involved than the Vette Brakes package though but Newman has done many of these conversions so you aren't reinventing the wheel and he also has the special pieces needed to make it work. There are some relatively minor changes needed to the C4 suspension itself and the shock valving and springs also needed to be changed in my case due to the lower weight of the 62 vs. that of the C4. You also need to make up new steering shafts to connect to the rack amongst other things.

While the C4 setup is likely the more sophisticated setup I guess, if I had the Vette Brakes package already sitting in my garage, that I would have to seriously consider going that route when considering the difference in cost in buying the suspension, differential, steering, brakes, etc. from a C4.

From what you have said though it sounds like you are having a new chassis made and you have the option of which suspension to use. Who is making the chassis and have they done a few that are on the road now? If cost is not a real issue, and the new chassis will accept the C4 pieces, (and they have whatever other parts are needed such as the steering connection, sway bar mounts, brake lines, emergency brake setup, torque arm, etc.) that would be a great way to go. You could always sell the other parts you already have. It would still be more involved though than the Vette Brakes package but that might be just what you are looking for although I can't tell you how much of a difference you will feel in ride and handling between the two. Also, I'd doubt there would be much difference between the C4 vs. C5 in that respect since, as someone else pointed out, the real advantage in the C5 is the strength of the chassis itself.

There are some pictures of our chassis on page 7 of our web site if you want to see that as an example. I have other more detailed shots as well if they would help you make your choice.

Rich Lagasse

 

[Last Ride]

Bryan,

I wrestled with the same question when researching the various suspension options for our 62. I have a 67 with the Vette Brakes Performance Plus package and, for the money and effort involved, it is a nice package. But, I was looking to do something different especially since they don't have a similar package for a C1. I also had a C5 at the time and was definitely leaning in that direction for the suspension on the 62 project.

After looking at what was involved in fitting the rear trans layout I decided to go the C4 route using the suspension from a 95. The changes to the body necessary to use the C5 setup on that car involved modifying the spare tire well as well as the gas tank area. The tire well was not a problem but there are only so many places for the tank and I didn't want to start making special dual tanks like the C5 uses. Also, the balance of the car (with the aluminum LS6 engine) wouldn't have been noticeably improved so, for the extra effort involved, it didn't seem worth it. That might be a different story though with a cast iron block.

I had Paul Newman (Car Creations) do the mods to the chassis itself and we did the rest including welding all the chassis seams to strengthen the frame. The C1 chassis is actually very stiff especially with the I beam "X" member. Going this route is much more involved than the Vette Brakes package though but Newman has done many of these conversions so you aren't reinventing the wheel and he also has the special pieces needed to make it work. There are some relatively minor changes needed to the C4 suspension itself and the shock valving and springs also needed to be changed in my case due to the lower weight of the 62 vs. that of the C4. You also need to make up new steering shafts to connect to the rack amongst other things.

While the C4 setup is likely the more sophisticated setup I guess, if I had the Vette Brakes package already sitting in my garage, that I would have to seriously consider going that route when considering the difference in cost in buying the suspension, differential, steering, brakes, etc. from a C4.

From what you have said though it sounds like you are having a new chassis made and you have the option of which suspension to use. Who is making the chassis and have they done a few that are on the road now? If cost is not a real issue, and the new chassis will accept the C4 pieces, (and they have whatever other parts are needed such as the steering connection, sway bar mounts, brake lines, emergency brake setup, torque arm, etc.) that would be a great way to go. You could always sell the other parts you already have. It would still be more involved though than the Vette Brakes package but that might be just what you are looking for although I can't tell you how much of a difference you will feel in ride and handling between the two. Also, I'd doubt there would be much difference between the C4 vs. C5 in that respect since, as someone else pointed out, the real advantage in the C5 is the strength of the chassis itself.

There are some pictures of our chassis on page 7 of our web site if you want to see that as an example. I have other more detailed shots as well if they would help you make your choice.

Rich Lagasse

Rich--
We actually exchanged a few emails a while back after I saw your car in a magazine and realized you were on the forums. I have spoken with Paul Newman Car Creations, and I think if I go through with this, it will be with the C4 setup. Here is the place I was looking at: www.streetshopinc.com and they have setups for a "C4 Shark" and even a C5 Shark. Now, the man admits to only doing a few C4 conversions, and NO C5 conversions (yet). He will build an entire frame (a la Car Creations-type) for $6495. Then, you can bolt on your C4 suspension, or he can do it for you. There are other options, but mostly minor stuff. take a look and tell me what you think. I know Paul Newman does some outstanding work, but I just don't think I have the time and money to strip my frame, ship it out there, get the conversion, and have it shipped back.

Bryan

 

[richscorvettes]

Bryan,

I do recall exchanging e-mails a while back now that you mention it.

I did see the Street Shops web site a few months ago and took another look at it now. Unfortunately, there isn't a whole lot of detailed information especially concerning finished products or options they offer. I'd suggest getting more information on those areas and speaking with their customers who have completed their cars. They should be able to tell you how well it performs and what was involved in finishing the project once they received the chassis. I also saw the link to Art Morrison's site on their site and wonder if he doesn't provide the chassis itself or some of the components. I don't know how close Street Shops is to where you are but it would be nice to see their work in person and maybe even a customers car.

The deciding factor for me, when researching sources for our project, was the experience and success that Newman had in having completed many cars. What you get is not only the physical conversion itself but the results of his experience in making the package work right and the components he has developed. Sometimes things seem a bit more expensive on the way in but in the end turn out to be worth it especially in how well it performs as well as reducing the number of headaches you'll encounter.

I can't offer more insight or thoughts than that on the Street Shops products but I can attest to the quality and end result of the Car Creations design.

I hope those thoughts help. Just send me an e-mail if you need anything else. Good luck on your project.

Rich Lagasse