chassis strengthing...``

gary@apt · Post by **gary@apt** » Sat Oct 21, 2006 8:34 pm

other than a roll cage to make shell more rigid someone suggested a process that seems to be done in the states where they inject a material like what powerflex bushes are made of in to the sills and box section and this make it lots stronger....

any one know any thing about it???

Post by **Stuart** » Sat Oct 21, 2006 8:38 pm

It may seem a bit of a bodge but a much lighter alternative is to inject the sills with normal DIY expanding foam. The guy that owns Newera, Miguel, has done just that on his AE86 and apparently it is pretty common practice.

I'll find some links and email it across with all the other junk I keep sending you :thumb:

shooter · Post by **shooter** » Sat Oct 21, 2006 9:32 pm

Seam weld the whole car will add almost as much stength and ridgity as a cage, plus loads lighter than the powerflex option.

As Stu said expending foam is a better option, in fact there is a dedicated automotive version which is much better than the normal household one as it doesn't shrink after time. No idea where its available from but I would guess Blacky would know or may even have a contact for a supply of this as used in motorsport loads.

sdminus · Post by **sdminus** » Sat Oct 21, 2006 11:01 pm

Gary. You need to speak to John webster or webster race eingineering. He should know all you need about chasis design and construction

Scott

PhatBob · Post by **PhatBob** » Mon Oct 23, 2006 9:05 am

Polyurethane foam is your stuff, comes in two tins, mix together and get a great display of foam and heat. The trick is to measure the right amount to fill the cavity, and the art is finding a way to stop the stuff expanding. It will expand to 25 times its volume but then its mainly air bubbles, if you can restrict the expansion to about 10times it exerts a positive pressure around the walls of the cavity which stiffens things nicely.

http://www.cfsnet.co.uk/acatalog/CFS_Ca ... LS_14.html

I think the Race and Rally car source book has the details on volume and strength:
http://www.amazon.co.uk/Race-Rally-Car- ... 06?ie=UTF8

Rob

SM · Post by SM » Mon Oct 23, 2006 10:24 am

Keep me up to date on any info you find Gary, I saw thought it sounded like it was worth looking into to.
I cant seam weld due to sprint class rules, not sure if I can foam inject, I'll have to read the blue book.

Pavlo · Post by **Pavlo** » Sun Nov 05, 2006 9:07 pm

SM wrote:Keep me up to date on any info you find Gary, I saw thought it sounded like it was worth looking into to.
I cant seam weld due to sprint class rules, not sure if I can foam inject, I'll have to read the blue book.

Are you allowed to "repair" sections of the shell? Surely those seam welds were done at the factory?