roadster vs locost?

[BackyardRacing]

Hi all, first post noob here!

been lurking for a while, and ready to take the plunge, and wanted a little advice from the guys in the know.

im currently stuck with deciding whether to start from scratch with a roadster build, or buy an original locost, (theres a couple on ebay look like good starting points).

i know the roadster has IRS and the locost is live, so im guessing the roadster will handle better, be more agile?

i dont like the "wide body" cars, and im not a big guy, so i want a slim looking car, as close to the original seven design as poss in appearance, but with the best possible handling, so im a little stuck on what to go for, as i believe the locost is slimmer (truer to the original design) than the roadster, and if i pick up an "unfinished car" i can save a fortune.

i was thinking maybe i could reduce the width of the roadster to make it look more like i would prefer, but then no body-panels will fit i believe?

on a second note, i cant weld, so would probably get a pre-welded chassis, i have noticed talon fabrication make these, has anyone from here bought a chassis from talon, any reviews of the quality?
not doubting anyone, just looking for some input, more to put my mind at ease i suppose being such a critical part of the car.

also i believe the locost will end up a tad lighter than the roadster, which must be a + on the performance/handling debate

thanks in advance, Ant

[vmax1974]

The roadster is only 4 inches wider than the caterham you could build the roadster narrower however as you said you then have the challenge of having to make or adapt bodywork to fit the locost is an old design now and you would have to source the mk2 escort and good luck with that on a budget the roadster is sierra based however these are thin on the ground now thats why a lot of people are starting to use the mx5 as a donor

Cant speak for the quality of talon's ready made chassis have only seen the ones that nathan at nts engineering search saturn sportscars and the look spot on to me

Hope this helps

Dave

[BackyardRacing]

yes, having owned a mx5 (mk1) for a couple years, i was tempted to go that route, as there great handling cars out the box, just seems a little more complex than the sierra based car, more wiring? and seems like it would certainly cost more, being my first build i thought maybe best to keep things simple/cheap.

[Eternal]

I had the same problem 2 years ago. The fact that the Locosts are getting kind of old helped me decide on the Haynes, The fact that a well established mx5 design is fantastic as in my mind these are the best donor around today.

The looks are not too wide when you see them in real life. To fix this i added an extra 175mm to the engine bay to stretch it out a bit more(not that it needed fixing!)

In my mind the Haynes has way more pros than cons compared to the locost. Also the community is fantastic! You should come to Stonleigh show and see some in the flesh. Im hoping to get my one down there un its unrunning state :)

[mgglep]

I can't speak for talon but I bought a chassis from Saturn with wishbones the quality was great every component has fitted first time I bought a chassis really because I felt I didn't have the space to build the chassis

[BackyardRacing]

Your car looks super clean, very nice!

Yes I have seen the saturn/nts chassis, there just a little pricier

[xBooglex]

Hi, I to have a talon chasis sat in the garage, the quality and accuracy of the welds are good. I have a couple of mates that are welders and they gave it the thumbs up!!!:) :) A decent chap also.

[Talonmotorsport]

Keep this under your hat, close to your chest and super hush hush but I have a 15% off sale on chassis'ies'es running on ebay untill wednesday SSSSHHHHH don't tell any body :D
Also has any body mentioned that a chassis will go on a car roof rack so collection is not as much of a bugger as people think it is.

[MarkB]

A well set up live axle Locost will rung rings round the wider Roadster.

[robo]

I drove a westie with a live axle <escort> and although it was ok I thought the unsprung weight of the axle was far to much for the car to the point that it was intrusive. The later ones with the sierra running gear ride much better but thats just me talking about a car for the road, track might be different.

Bob

[Eternal]

...and a well setup Roadster will run rings around a standard locost. :D

All depends on time and cash.

[MarkB]

...and a well setup Roadster will run rings around a standard locost. :D

All depends on time and cash.

Sooner a speed boat than a barge:p

[robo]

Best we tell all the race teams in the world + F1+ the car companies that they are all wrong and to put live axles back in the cars cos they are bestest:rolleyes:


Bob

[MarkB]

Doesn't matter how the drive is transferred to the road, whether a live axle, IRS or Dedion.
The important bit is geometry so it actually works.

[robo]

Cant accept that you can have something as heavy as an axle which weighs as much as the back end of the car as unsprung weight. All ok on a billiard table race track but show the car some shite roads and it will skip about all over the place. I have driven both and thats exactly what the live axle does, its just not compliant over potholes etc.

Bob

[MikeB]

not much between an independant and a de dion (caterham). Live axle ok for track use.
As mark says though the geometry has to be right.
I haven't seen any graphs of the camber gain vs deflection for the haynes.
The rear is the easiest to get right, it's lot harder to get the front right especially with the constraints of the front uprights.

For me it will be about on road fun with the odd track day, it should be a laugh what ever, as long as I have enough power to pop the back out for a bit of controllable fun I'll be happy!

If I'm unhappy down the line I'll look at changes to the geometry.

to the OP, i'm sure there are many locosts running with independant rear ends. That way you'd get the best of both

[BackyardRacing]

Thanks for the input so far guys

To add to the debate, what's people's thoughts on the mx5 based roadster vs the sierra based roadster?

Are the mx5 components lighter? I know the Mazda
Engine is somewhat more powerful than those stone age pinto's.

But, I take it the mx5 route is more expensive and complicated?

[skov]

The wiring is probably more complicated if you take the MX5 route.
The rest isn't any harder, and in some ways it's easier as you don't need to make new rear uprights, or add those mushroom things to the front ones.

Not sure it's any more expensive either. The donor might cost you slightly more than a Sierra but MX5 parts are still in demand and you can cover the cost of the donor (and even make a small profit) selling the bits you don't use.

[brainbug007]

I'm not sure the wiring is any worse with the mx5 compared to the sierra. I've removed at least 2-3 bin bags of wire from the sierra loom that was either redunant or just too long and had to be shortened.

[robo]

I'm not sure the wiring is any worse with the mx5 compared to the sierra. I've removed at least 2-3 bin bags of wire from the sierra loom that was either redunant or just too long and had to be shortened.

We know that:eek: :rolleyes: :)

Bob

[MarkB]

Geometry is everything with a car like a 7, get it wrong and you have a pig.

[BackyardRacing]

so are the mx5 uprights etc better than the sierras? i.e not having to use mushrooms etc. is the geometry any better?

also is there any weight differance between pinto setup and the mx5 setup?

lastly, i really dont want a bonnet scoop/bulge, will the mx5 motor fit under standard bodywork?

cheers again, sorry to pester :p

[vmax1974]

The mx5 does not use the mushroom adapters

Dont know about the weight difference

The bonnet will need a bulge to clear the plenum on the mx5 engine

[Not Anumber]

With a change of airfilter/ airbox the MX5 motor will sit under the Roadster bonnet. It also gets away without needing to modify the sump and oil pickup.