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Sbarro C2
JC - 22/8/05 at 05:30 PM

Anyone seen this this? The rear end is exactly what I am planning! A picture of my progress is in the seating forum! Rescued attachment c2-v6-4.jpg
Rescued attachment c2-v6-4.jpg


Alan B - 22/8/05 at 06:03 PM

A good way to go if you can live with the height of the struts...very simple and clean,, but for me, sadly, it was too high.


TheGecko - 24/8/05 at 02:26 PM

I often see this lament about the height of struts and how they make a strut rear end on a FWD based middy "impossible" or "unacceptable". There must be some vastly different struts to the Corolla ones that I have.

The highest point on my 20-valve 4A-GE engine is the intake plenum at 800mm (based on engine set a close to factory height - it could probably go as much as 50mm lower). The top of the standard strut, at ride height, with a good 75mm+ of bump travel available, is 850mm. Given that the engine cover will need at least a little clearance above the engine, the top of the struts ends up basically level with the engine cover. I just don't see how this is "too high".

When I first started laying out my car I accepted the "too tall" wisdom and started to design various de Dion type rear ends, involving a fair bit of fabrication and fiddling around. Once I actually set up the engine and a strut at ride height I realised that everything would fit quite nicely. Now my component fabrication list for the rear end is a pair of simple, wide-based A-arms that will even use the stock Toyota lower ball-joint. I'm also converting the stock struts to coil-overs using some cheap, effective kits bought from a local suspension supplier ($38.50 each - that's about USD30 or GBP16).

There's been a bit of fiddling around to get properly braced top strut mounts into the chassis design but that's pretty much resolved now. When time permits I'll put up some photos of the 1:6 balsa model that shows the rear end layout.

So JC, don't be scared off - just measure what you've got and make it fit.

Best regards,

Dominic


kb58 - 24/8/05 at 02:36 PM

Good point Dominic. I agree somewhere along the line rear struts got to be a dirty word. Chapman used them in his sports cars and they handle wonderfully. I couldn't use them because I forced the drivetrain inside a Mini shell so there just wasn't room. But if I were starting from a clean sheet I'd very much consider them because of how compact and simple they are. Not perfect, but so what.

[Edited on 8/24/05 by kb58]


Alan B - 24/8/05 at 02:44 PM

Ok...you've convinced me.....


JC - 24/8/05 at 02:48 PM

Thanks guys! Gecko - I believe similar kits are available here - they are a threaded tube to weld over the strut to give you adjustable height with coil-overs. My question to you is: How are you making your top mounts?

I agree that the 'too high' argument is sometimes misleading - as my car is basically a wedge anyway, it doesn't bother me! Her is the photo from the seating post of my progress!:[img]http://locostbuilders.co.uk/upload/a248888-DSCN3752a[1].jpg[/img]


Alan B - 24/8/05 at 03:18 PM

Looks good JC...what are your tube sizes?


JC - 24/8/05 at 03:36 PM

Alan,
50mmx50mm 16g square
50mm 16g round
Front suspension (yet to be added) 25mmx25mm 16g sq
Rear cradle, 25mm square again
'tunnel' from 18mm sq 18g.

No hi tech FEA I'm afraid, just a model to test rigidity!

It isn't as heavy as it looks!


Alan B - 24/8/05 at 05:04 PM

quote:
Originally posted by JC

......It isn't as heavy as it looks!


yeah, I know...the 50 x 50 is only double the weight of 25 x 25 yet 8 times stiffer (rough figure, but that kind of magnitude)....too many go for thicker wall when a bigger section is the answer....


Spyderman - 25/8/05 at 06:42 PM

The main problem when using struts, either Chapman or McPherson from the donor car is not the height but the damper and spring ratings.
Don't forget they were made for cars weighing 3 times as much as your own projects.
You may well be able to get lighter springs made to fit, but the damper will still be wrong and after all the cost of converting them you may as well put coil-overs on!

Just another opinion!

Terry


TheGecko - 25/8/05 at 09:50 PM

quote:
Originally posted by Spyderman
The main problem when using struts, either Chapman or McPherson from the donor car is not the height but the damper and spring ratings.
Don't forget they were made for cars weighing 3 times as much as your own projects.
You may well be able to get lighter springs made to fit, but the damper will still be wrong and after all the cost of converting them you may as well put coil-overs on!

Well, maybe not 3 times - the Corolla that I'm using as a donor wouldn't be much more than twice what my finished car will weigh but, yes, I know what you mean. However, most modern struts are rebuildable - ie the damper is a replaceable insert. I'll be using double adjustable Koni inserts.

As for springs - it's straightforward to cut the stock spring seats off and add a cheap (ie < AU$40) collar for standard size 2.5" coilover springs. Here's a few photos of just such a conversion on a friends car (although with RWD type struts rather than FWD - principal is identical).




Hope this clarifies things a little,

Dominic


JC - 26/8/05 at 05:53 PM

The issue of using struts is not just one of cost - to use double wishbone/coilovers would mean some design work to make it work properly - I tried but didn't have the knowledge/experience to properly sort it out! If I can't adapt the donor strut, I'm planning to substitute one of those rather nice pro tech struts, which is adjustable.

If I use the donor stuff, I may use the rear shock, which will be softer as it is designed for less weight!


TheGecko - 27/8/05 at 12:52 AM

I've just been involved in a very similar discussion on another forum and I took the time to photograph my donor Corolla powertrain and overlay a few major dimensions. Since it may be of interest to some people here too I'll post the link.

Hope this helps someone,

Dominic


robinbastd - 27/8/05 at 09:42 PM

Dominic,you are a star!
Have silvertop in the workshop all the other projects are being finished off.
Soon it will begin!
Cheers mate!

Ian


Triton - 27/8/05 at 10:15 PM

bondage streetfighter.......