I'm not sure what he's referring to but...

Some of the hardcore Sentra SE-R racers (SCCA, IT) have used that spray foam stuff that hardens after expanding (i.e. Great Stuff). They sprayed it into the holes of the frame. Some of these holes are only accessed thru the inside floor pan so it would require the seats and carpet to be removed.

Anyone heard of Mike Kojima (Nissan Engineer)? He did this on his SE-R cup car and claims 40% chassis stiffening. I'm definately gonna try it...not that expensive, especially for those kind of gains!!! Good Saturday afternoon job.

 

It is true and you can also do it to newer cars to. This has long been a trick of racers to strengthen the chassis. You tack weld every point on the bottom of the car which can increase stiffness up to 50% also another almost unkown chassis stiffining process over here but is big in japan is foam injection. The process is pretty cheap and good results can be had. The process is to fill your Frame, fenders, and anything else that can shift under cornering with a liquid to foam injection. I have heard of a lot of Drifters doing this and I am looking into doing my frame rail. This can also stiffen the chassis a good bit. Anyway your friend is right tack welding will increase stiffness in the chassis, but it is a pain to perform and a long process. Stubby

 

next time please put tech questions in the general tech section.

 

DOes anyone have some pics of either foam being applied or tack welds??

 

Actually I don't have any pics but if you look in the new Turbo, Import Racer they have a Nissan SE-R that they do the frame injection to, It says you are to use a rail injection kit from this company but I have been trying to out info about and I can't find it any where. Also the tack welds can be seen in the SCC September 2002 issue under J.A.S engineering. Here is a pic of one that I found not a very good job though, but it is hard to find pics of this stuff. Stubby
Seam Welding

 

I have been looking for days now on where to get the proper foam sealing kit and here is the website...Stubby

Frame Rail Injection

 

I have been looking for days now on where to get the proper foam sealing kit and here is the website...Stubby

Frame Rail Injection

That's the same URL as the one you posted above.

 

Ok I don't know how that happend but here it is again and this should be right... Stubby
Foam Rail Injection

 

Thanks for the link...I'm smelling a group buy!

Any takers?

laterz...Jody

 

I have been looking into buying this stuff for days and now I really want it. For the money you can't beat the performance. Stubby

 

Hey guys the more kits we buy the cheaper it is. We should start a sort of group buy so we can get the cheap pricing they have listed on the site. I really want to stiffen the body of my old ass S13. I want to AutoX it next year and want the chassis as stiff as possible. I am also going to add a roll cage will add some more stiffness to the body.. I have seen these kits too on my 180SX Magazine from Japan that has all these bars that bolt up under the fenders in the front, across the engine bay, the rear and under the car.. Pretty bad ass. Anyhow lets get some people together and we buy by the case.

http://www.itwfoamseal.com/auto_after_ordering.htm

 

We need at least 5 of those kits to fill the entire chassis right? (I read they used 5 to fill the 300ZXTT chassis)

I wonder how much weight that would add...

 

Aren't cars designed to crumble at certian points in the event of impact?

I've read several places that doing this will increase your chance of injury since the car transfers the impact to your body rather than absorbing it like it was meant to.

I'd stay away from this sort of stuff on a street car...

 

I imagine that might be true to a certain extent, but any impact that is going to bend the frame, is more than likely going to injure you anyways.

I agree, I wouldn't do it on a street car, unless I had bucket seats and a 5 point harness. I don't think it's necessary though. There's so much more that needs to be done first in order for it to work the way it was meant to. A stock suspension will not utilize a stiffened chassis very well because of the body roll that will occur with stock shocks and wheels. At least, I don't think it would.

If you want to reinforce the chassis, that's what swaybars and strut tower bars are for.

 

Well most people that are going to do this already have sway bars or STB's. If I can have a 50% stiffer chassis for less than $150 then I will take it. This has been used for years in Japan by street drifters. A car is made to take the impact so you don't have to but a hard foam will break if put under the kind of pressure needed to bend a frame.. Stubby

 

sounds VERY interesting. if anyone is starting a group buy, go ahead and count me in.

 

Well most people that are going to do this already have sway bars or STB's. If I can have a 50% stiffer chassis for less than $150 then I will take it. This has been used for years in Japan by street drifters. A car is made to take the impact so you don't have to but a hard foam will break if put under the kind of pressure needed to bend a frame.. Stubby

You would hope so, but I highly doubt that everyone that is interested in getting a GB together has swaybars and strut tower bars, though I could be wrong.

 

Well, I'm in!

I'll take 10. Five for the SE-R beast and 5 for the 240 daily.

laterz...jody

 

i'm gonna go ahead and advise against this.

anything that seems too good to be true, usually is.

1) if the foam is soft enough to break in an impact then how does it......
2) successfully reinforce the chassis by 50%?
3) not that i'm the end all source, but i've talked to a fair number of LEGITIMATE RACERS and worked on a few race cars in my day, and i've never even seen or heard of this stuff.
4) the fact that "japanese drifters" use it makes me cringe by itself

i dunno bout this stuff guys

 

Then why would SCC recommend it on a car? As for the breaking imagine lets say great stuff ok. It forms into a hard shell, but if you try and break a little but off you can do it faily easily. I am not saying that on any impact it will break I was saying that if an impace hard enough to bend the rail will most likely break some of the foam... Also what type of "race cars" did you work on? I have worked in the ASA on the pit crew a few years back and they don't use, but that doesn't mean other racers don't. This is a new concept over here and some people won't think it works, but that is fine. I have also talked to people that say seam welding doesn't work which seam welding does work, and this is just a form of "interlocking the frame for better strength. Stubby

 

I would imagine that in a lot of racing leagues this kind of thing would be against regulations.

 

Panoz GTS, SRF, SRen are the ones i've worked on.

why would SCC recommend it? because the company paid them to. SCC has been going downhill ever since they got their new editor, i don't trust them near as much as i used to.

i've never heard anybody mention the stuff in the 15 (not that 15 is very many) or so times i've been at the track.

i'm not saying it's impossible for this stuff to work, i'm just saying i'm skeptical, and i think there are better ways to go about doing the same thing.

EDIT: Dubble you're probably right about that, i should look in my rulebook if i can find it........

 

Hey guys the more kits we buy the cheaper it is. We should start a sort of group buy so we can get the cheap pricing they have listed on the site. I really want to stiffen the body of my old ass S13. I want to AutoX it next year and want the chassis as stiff as possible. I am also going to add a roll cage will add some more stiffness to the body.. I have seen these kits too on my 180SX Magazine from Japan that has all these bars that bolt up under the fenders in the front, across the engine bay, the rear and under the car.. Pretty bad ass. Anyhow lets get some people together and we buy by the case.

http://www.itwfoamseal.com/auto_after_ordering.htm

are you talking about these
crossmember bar(monkey bar)

side floor support bars

front ladder bar

rear ladder bar

 

no he's talking about a hardening foam that you inject into the frame rails and what not.

 

..... I have seen these kits too on my 180SX Magazine from Japan that has all these bars that bolt up under the fenders in the front, across the engine bay, the rear and under the car....

i was referring to this statement regarding bars and stuff.