Strengthening the NSX chassis - Would Rewelding help ??

[MvM]

It seems to be a rather well know fact that the NSX chassis is very strong and rigid.
However, whenever a NSX is being made ready for serious track work, lots of things are done to make the chassis even stiffer than it already is.

I was wondering just how much stronger & more rigid the chassis would be even one would put in the time and effort into redoing the welding of the chassis.

Just like every other car, the NSX chassis is spot-welded everywhere, meaning that two parts are not connect but a single, long weld but by placing a line of spotswelds along the line where two separate parts will meet.

Would replacing or redoing these spotweld with a continous weld really make the chassis stronger, or would it not make that much of a difference.
This all assuming the work is being done in a (very) professional manner of course.

 

[Nefarious]

It would be a minimal change. Adding a cage and cross braces is the only way to truly stiffen the car.

 

[A.S. Motorsport]

Indeed adding tubular bracing to the subframes and a full cage would be the next big step, after nsx-r brace and strut & tie bars.

 

[02#154]

Seam welding makes more than a trivial amount of difference in chassis rigidity in other cars and I can't imagine why it would not prove beneficial to the NSX chassis as well. If you can feel the difference in the HANDLING characteristics between different spring rates (not just the ride/comfort or additional confidence difference but actual HANDLING), you will feel the additional performance seam welding offers. But it certainly is not a mod that is cost effective for most because most of us aren't good enough to appreciate the differences.

You'll feel the difference but whether that translates into faster lap times will depend on how good you are. Are you that good? :biggrin:

In the two cars I've prepared for dedicated track work (both were steel chassis 240SXs), we didn't do one or the other, we did both seam welding as well as a cage because at that level every bit adds up. (I wasn't the driver for either car.) Admittedly, if we had to choose only one, we would have to go with only a cage, but for a dedicated track car, seam welding makes sense.

So to answer your question, I would bet money that seam welding would make the chassis stiffer. The question then becomes whether you will be able to realize any performance gains because of it.

One note: our welder said that welding aluminum is significantly more difficult than welding steel so if you take this esoteric step, make sure it's done properly by a qualified welder. You sound to have this base covered, but it bears mentioning because it's an expensive chassis to make a mistake on.

J

 

[StmpoRaceProducts]

It seems to be a rather well know fact that the NSX chassis is very strong and rigid.
However, whenever a NSX is being made ready for serious track work, lots of things are done to make the chassis even stiffer than it already is.

I was wondering just how much stronger & more rigid the chassis would be even one would put in the time and effort into redoing the welding of the chassis.

Just like every other car, the NSX chassis is spot-welded everywhere, meaning that two parts are not connect but a single, long weld but by placing a line of spotswelds along the line where two separate parts will meet.

Would replacing or redoing these spotweld with a continous weld really make the chassis stronger, or would it not make that much of a difference.
This all assuming the work is being done in a (very) professional manner of course.

I would advise against this for many reasons... tons of reasons actualy..

But good original thought

 

[goldNSX]

esoteric step

I think it would make more sense to sell a Targa and buy a rare Coupe.

 

[Nero Tenebre]

It seems to be a rather well know fact that the NSX chassis is very strong and rigid.
However, whenever a NSX is being made ready for serious track work, lots of things are done to make the chassis even stiffer than it already is.

I was wondering just how much stronger & more rigid the chassis would be even one would put in the time and effort into redoing the welding of the chassis.

Just like every other car, the NSX chassis is spot-welded everywhere, meaning that two parts are not connect but a single, long weld but by placing a line of spotswelds along the line where two separate parts will meet.

Would replacing or redoing these spotweld with a continous weld really make the chassis stronger, or would it not make that much of a difference.
This all assuming the work is being done in a (very) professional manner of course.

The first step is to buy a STMPO front chassis bar, front strut tower bar, rear strut tower bar if you want a more rigid chassis. I have a targa and it is rock solid after getting these installed. Next, if you want more predictable handling at the limits, you need to get all the non compliance hardware (front clamps, rear beam bushing, etc). If you are going to track a lot, then I would move on to a roll cage but I doubt you will find that your car is not enough after doing the other stuff.

 

[pgilliam1]

i think it would make more sense to sell a targa and buy a rare coupe.

bingo!

 

[02#154]

Interesting… none of you answered the question of whether seam welding will make the chassis stiffer or not. I think it will.

All the rest of you have done is made alternative suggestions (which are all valid ways to stiffen the chassis) but I don't think the OP didn't kow about those other ways. He wants to know if stitch welding will make the chassis more rigid. What you've all done is akin to him asking if a front splitter offers more downforce and answering that if he wants downforce he should get a big ass wing.

Anyone care to disagree with my supposition? I'm willing to listen. Just don't talk about what should be done before or after seam welding or why other options are recommended or whether a whole other car is the answer. Let's talk about what the OP wants to talk about, how about that? See, I honestly don't know why a method used to strengthen a steel chassis would not also work on our aluminum chassis.

J

 

[swift996]

I've seen people add a ton of spot welds and urethane sealant. It adds good rigidity, but for the cost there's a lot better options out there.

 

[mrbozo1]

It seems to be a rather well know fact that the NSX chassis is very strong and rigid.
However, whenever a NSX is being made ready for serious track work, lots of things are done to make the chassis even stiffer than it already is.

I was wondering just how much stronger & more rigid the chassis would be even one would put in the time and effort into redoing the welding of the chassis.

Just like every other car, the NSX chassis is spot-welded everywhere, meaning that two parts are not connect but a single, long weld but by placing a line of spotswelds along the line where two separate parts will meet.

Would replacing or redoing these spotweld with a continous weld really make the chassis stronger, or would it not make that much of a difference.
This all assuming the work is being done in a (very) professional manner of course.

Yes it will make it 12.342% stronger:tongue:

 

[Xetronic]

I would advise against this for many reasons... tons of reasons actualy..

But good original thought

Could you please elaborate on this? I would like to hear this out. As many have state that welding the chassis together usually would be an improvement, however you have a different view. I think it would be nice to shed some light on this with regard to the NSX.

Thanks!:smile:

 

[pgilliam1]

If there was a weakness in chassis rigidity or strength, don't you think the Cray computer would have found and corrected it, especially if it was just additional welds? The targa roof was for sales, not performance.

 

[Nero Tenebre]

Interesting… none of you answered the question of whether seam welding will make the chassis stiffer or not. I think it will.

All the rest of you have done is made alternative suggestions (which are all valid ways to stiffen the chassis) but I don't think the OP didn't kow about those other ways. He wants to know if stitch welding will make the chassis more rigid. What you've all done is akin to him asking if a front splitter offers more downforce and answering that if he wants downforce he should get a big ass wing.

Anyone care to disagree with my supposition? I'm willing to listen. Just don't talk about what should be done before or after seam welding or why other options are recommended or whether a whole other car is the answer. Let's talk about what the OP wants to talk about, how about that? See, I honestly don't know why a method used to strengthen a steel chassis would not also work on our aluminum chassis.

J

Well a lot of times people ask the wrong questions on the way to achieving a goal when there are better ways to achieve that goal. He hasn't answered if he explored the other avenues first

 

[StmpoRaceProducts]

Could you please elaborate on this? I would like to hear this out. As many have state that welding the chassis together usually would be an improvement, however you have a different view. I think it would be nice to shed some light on this with regard to the NSX.

Thanks!:smile:

Simple... the NSX is one of I think 3 100% aluminum cars - could be wrong for the google and wiki people.. but its close

So the first major reason would be welding aluminum and welding steel are two different beasts that have the same ending result... the weld is stronger than the material.

The weld is stronger due to the heat cycle you place on the material... the weakest point now becomes directly left and right of the weld

When you look at the materials prior to welding them individually... steel is strong and aluminum is not.

In this video you can see us tig welding our coolant tanks as I used a welding helmet over the camera.

<iframe width="560" height="315" src="http://www.youtube.com/embed/BV69yTmQnG8" frameborder="0" allowfullscreen></iframe>

This is very clean and treated aluminum. Pause the video at :53 seconds and also at 1:36. The white wake on both sides have imperfections seen in black wake. at the :53 point it is an inch above his stop. at 1:36 it is all around the end which is difficult to avoid on this shaped piece.

This contamination is just oxygen... contamination from seam sealer is exponentially worse.. and oxygen will be there too.

Second major reason is our experience welding to an NSX chassis.. which I don’t think anyone else has more experience there... the seam sealant doesn’t like the heat.. it actually moves towards the arc as you weld it. and man does it give you a wicked headache... we tried everything to remove it so

But welding for strength is 100% about cleanliness.. it is impossible to weld this chassis without contamination... I guess a full acid dip and full disassembly prior to re-welding it would work.. but reason #1 comes back into play.

So to avoid both major problems with our race build found here

http://www.nsxprime.com/forum/showthread.php?t=134599&highlight=stmpo+k20nsx

We welded 3/16 and 1/4" place to every pipe we connected for chassis rigidity. This helped us stay away from seams... this discussion is about welding seams.. we went out of our way to avoid welding seams after we experienced the sealer and the arc from the tig.

examples showing that the seams have the dirtiest welds and also how aluminum plate was placed away from them.. when we could.

That is just the major reasons though

 

[02#154]

If there was a weakness in chassis rigidity or strength, don't you think the Cray computer would have found and corrected it, especially if it was just additional welds? The targa roof was for sales, not performance.

Your question cannot be answered with just yes or no, so forgive the lengthy reply:

First, this isn't about a design "flaw" that caused the chassis to be weak. It's a question of whether seam welding would make it even stiffer. We all know the NSX has an excellent chassis on which to build a performance car. So, no, I don't believe their computer revealed a weakness and they ignored it.

Neither I nor you know what the design targets were for weight, strength and cost of the chassis. I'm pretty sure they designed a chassis, let the computer do its analysis and then massaged the design over and over again until their goals were met. I'm betting that more rigidity could have been gained over what their end result was (the fact that they later installed the chassis bars on the type r is evidence of this assumption).

But gaining that added rigidity would have had a penalty to either the cost or weight goals that they also had to adhere to. Surely you don't think that the designers ended up with a chassis that was ABSOLUTELY twist and bend free - that's literally impossible. There was always and always will be room for improvement in chassis rigidity but not at the budget and weight goals that they had. Evidence of this is the reinforcement done by Ross that he shares a few posts above. It at least appears to me to likely have a beneficial impact on chassis rigidity. I'm sure Ross believes he's improving the chassis or else why would he do it? But if Honda did those same techniques, they wouldn't have room for all of the other stuff that usually goes there and they likely would have totally blown their weight targets.

In the case of seam welding the chassis at the factory, the reason NOT to do it may have outweighed the benefits, especially since their rigidity target was met without it. Seam welding would have cost more, and as much as we like to believe that a given car is built with "no compromise", it's just not true. Even the NSX had a cost budget.

J

 

[MvM]

Thanks for all the informatieve replies.

Actually, I was not really planning to actually do this rewelding though.

However, when rereading some NSX related articles (which I do quite often), I came across a German article in the Sportauto Magazin on the preparation the an actual NSX-R for the 24 hour race at the famous Nurburg ring.
To get this car ready, they actually stripped the car down and rewelded all the seams, THEN installed a full tubular steel roll cage and THEN added some chassis bars as well.

As a note, I currently have a NSX-T and have installed the NSX-R bars, but the car certainly flexes more than my previous NSX Coupe I had before.
Currently, apart from getting a set of Recaro PP seats ready and getting some nice new red carpet and get the CTSC installed, some additional chassis stiffening would be welcome though

 

[stuntman]

It will weaken the chassis as aluminum goes soft above 300*F. Unless you re geat treat the entire car, youll greatly reduce its strength.

 

[Floyd]

I've never had the pleasure of driving a coupe, but I just installed the type-R bars and its day and night. I daily drive mine, so I'm not looking to make it the ultimate track car, but would highly recommend the chassis bars for those that haven't done them for the T. It would have been nice if the car had come this way. Much like the CT blower.

 

[LJSB]

Your question cannot be answered with just yes or no, so forgive the lengthy reply:
J

I really don't have a comment I just want to see a larger version of your avatar.
Perhaps in the "girls and NSX'S" thread?