Locost GT40

[glen]

ok..help needed quick, been offered corvette c5 front uprights today, remember reading somewhere that these can be used on some chassis. as i'll be building my own chassis, i can mount my wishbone mounts where needed. can anyone shed some light on which chassis used these uprights? it would be much quicker to copy the chassis (front end) so i can use these!......i shall sit here looking at my screen until i get a reply
remember, you must keep the enthuiasm up to stop another "unfinished project" appearing on fleabay:evil:

 

[Al Jones]

Glen,you might contact Chris at Active Power.He makes a nice chassis for his track coupes using modern components and geometry.I believe this chassis incorporates the C5 Corvette suspension parts.Might save some money to price out parts or the entire unit as these are meant to be used with GT40/McLaren and Lola style bodies. You can find him right here;he's a forum member. A.J.

 

[Bram Boekestein]

Hubs from a corvette are used a lot, but complete uprights? Factory five uses them on cobra's.

Don't use front suspension from car A and rear suspension from car B and think it works. Sure you can use corvette uprights but you'll need to make your own chassis to make it work allround.

So if you're doing a scratchbuild, get those uprights, but design your own chassis.

regards,
bram

 

[Doug Clark]

I'm using C5 - Z06 uprights, wheels, brakes on all 4 corners of my car.

The only disadvantage I see to them is that they have a weird PCD (outside the USA) and the required offsets are close to unique as well, so this limits the available wheels to really expensive good after market wheels made for Corvettes, cheap crap after market wheels made for Corvettes or cheap oem wheels from flea bay, like these...

Which I paid US$550 for, from a C06 I think.

And all of these you'll need to get out of the USA or the price will be double I expect.

Luckily for me I fly stupid amounts for my job and get to go to the USA a couple of times each year, so I can tell you 4 Corvette wheels won't bust the USA style (FB) luggage allowance.

If you need wheel bearings - hubs for C5 uprights, buy them straight from SKF in your country it'll be the cheapest way to go for sure, I can dig the part numbers out when I get home if required (In China at the mo).

Personally I think the C5 A arm geometry looks crap, so I decided not to go that way and make my own A arms instead. The ammount of anti-dive in it just looks silly to me. But I assume GM engineers know just a little bit more on the subject than I do having never design a car beofre this one.

Also the lower ball joint on the C5 is a press in unit to the A arm, I never found a bolt on ball joint to fit the upright so a normal "Locost" style lower A arm is out. And becuase of the captive ball join in the top of the upright you have to have rose joints or some other method of camber adjustment on the inner end of the A arm if you want to be able to adjust that.

This is what my plan is...

 

[glen]

cheers for the reply doug, i am in a position where i go to the usa 3 or 4 times a year, but i don't want a wierd offset or anything that will limit my choice of "cheap" wheels, this is a "locost" afterall!! i can get skf bearings local to me so that is not a problem, the bloke that is selling the uprights is 12 miles from me and i can get them tomorrow (if i wish)
but certain things must look good even with a locost (8 trumpets, nice wheels etc)!!
i'm not that scared about front uprights as i can fabricate arms to suit (trawling the net is free, but time consuming) but the seller said corvette use the same uprights on the front and back, (i know nothing about corvettes, but find this hard to believe)

 

[Fran Hall RCR]

Glen,

left front becomes right rear and visa versa with the C5 uprights...

 

[glen]

cheers fran, but how do the reverse wishbones mate with the rear uprights? (remember, i haven't seen these in the flesh yet...still learning!)

 

[Fran Hall RCR]

Same as the front.....

Factory Five uses these parts on their GTM...

Photo Gallery GTM Supercar Chassis

I am not a donor type guy due to the compromises but it works for many manufacturers...

 

[glen]

the gtm rear set up is not what i want really, the front looks usable but for the rear, i would like something like this

with lower reverse wishbones and uprights. these are lola uprights but i have seen similar when searching the net. who makes these? i don't have to have alloy, just want this type of rear set up, they would also go with the chassis plans i have.

 

[Bram Boekestein]

You mean you want original reproductions? SouthernGT makes them at almost 2k complete. But a more gt40 replica company's do them.

How much does that guy want for the front c5 uprights?

 

[glen]

2k is too much. the c5's are £150 for a pair , seems good?
can i get the taper reamed to a more user friendly balljoint taper?

 

[Bram Boekestein]

You can buy a reamer for 75 or so. 150 isn't much at all, you can barely get them on this side of the pond.

 

[Eddie]

Glen,
You can get the reamers 7&10 deg. from speedway in the states at a very reasonable cost...I like the way your going with this..some people don,t understand that we do not all have bottomless pockets for our projects..{ they,ll use more money on their argon than on the steeel}...every fool knows that the steel..unless your using T75 or 4130 ..is the cheapest part off the build..keep up the good work.
Cheers Eddie.

 

[Doug Clark]

The C5 uprights are the same front and rear, there are just right and left versions.
The hubs that bolt onto the upright are what makes it a front or rear item.
I paid ~US$100 each for the uprights on flea bay and then another ~A$250 each for the hubs to suit.

The top ball joint is built in, the lower ones are roughly US$70 each new (moog).

Its not the taper that's the issue with the lower ball joints but the length required as they need to be long to get through the thick alloy section.

If you were brave this could be machined down so a bolt-on type ball joint could be used. I wouldn't do it though.

 

[Bram Boekestein]

Doug,
What kind of stub axles are used? 108mm (930) CVs are being used by Fran, but Corvette uses an other system, so standard stubaxles aren't useable I think.

 

[Jack]

Glen
how locost can you go. No such thing in the same sentence as a 40. Great idea but it will remain somewhat expensive. Self-built chassis using Corvette suspension and a second hand engine is a start. Gearbox and adapters will be the big challenge as well as some decent bodywork and windscreen. Wish you the best for this project but I can't see it done for less than 25K.

 

[Doug Clark]

I can't claim original thought on the drive shafts refer to post 24 on this thread.
I've yet to find a sensible price source for C5 out CV's - stub axles, does anyone know of any?

BTW I've not bought the part for this yet myself, but I assume it works as described.

 

[Bram Boekestein]

Found some at dutchman axles, but they are $750 a pair.:shocked2:
Those dune buggy sites don't really tell what they sell.

Maybe that cv on a corvette driveshaft isn't such a bad idea.

 

[glen]

well, i phoned the guy with the uprights today, told him about the lack of pcd choice i'd heard about and he said " happens so that i got a set of 18" bbs split rims to fit, oh and some wilwood calipers, and some wishbones):idea: if he's got wishbones, then, hopefully he's sorted the lower balljoint problem. even if i use his wishbones and fabricate them, i'm on to a winner!
molleur, i can go cheap!! i'm not building a le mans rep, i'm building what i want. and that's a sprint hillclimb type thing. so alloy interior "cheap" is what i like! 1 bucket seat, nice wheels etc.
certain things need big money, like adaptor for box to 302, manifold, wheels, etc but even a manifold can be made if you can weld. i know someone who spent 18 months on thier manifold, but each pipe is 1 length, no welds, work of art, but cheap.
i want a nice manifold because that is the picture in my head from when i was about 10 yrs old!!
wheels can be done lo cost by using cortina uprights which means loads of cheap period wheels, but i think wheels is one of those area's that you must get right.(for you, not every one else)
but the rest can be done on a smaller budget than millions!
as long as i like it, i'll be happy!

 

[Jack]

Glen, that's the idea. Go with what YOU like and all else be damned. I'm on a very tight budget for my build as well and my labor is free. I've been fabricating some very nice additional parts, brackets, gearbox mods, etc. on the cheap. They all look first class and are functional. Don't loose the dream! It can be done.