Strut Bar?

[72240z]

You do know that cars are built on 100% math and science and deciding what improvements need to be made is 100% math and science. But hey, who needs numbers and accurate testing....

 

 

 

I'm very curious how you know this. What particularly warrants a strut bar on a 510? If you know something others don't, please do tell, because I have a real carbon fiber strut bar in my garage I haven't put on, but if you can give one example that is credible I will think about using that 300 dollar paper weight.

 

Also judging from the stuff HRH has said on his web page I would suspect things he says anyway....

 

 

 

 

Yes, two different things. The strut bar keeps the suspension geometry accurate on cars that flex too much and the sway bars help to keep the car flat in the corners. :)

 

Math and science is all good and well but I don't need it to tell certain things. For example when I see a datsun tracked on a regular basis and the paint/windshield gaskets are cracking/warping I know the car is flexing. No formulas required.

 

Testing is good but you know what the cars are over 30 years old, shits been tested plenty by companies like nismo and cusco along with racing legends. It's interpretation of that testing that this always comes down to in my opinion. What I think the issue is, is that most bars can't handle the force under real usage and flex negating the point of using them. There have been a lot of talk on it and thats one reason (of many) why most race cars don't even use them, what they do though is weld in bracing which is just plain better but still to help with the same issue.

 

I'm not trying to argue and I'm not trying to back anything anyone said. I do my own thing and everyone else can do theirs. What it comes down to though is ALL cars flex if pushed properly on a track, that's just a fact. Do sway bars help with this? From my experience yes they do even if it's a small amount. Whether the cost is worth the gain is up to each person. For what its worth a capable person could weld up a thick bar for a few bucks. $300 bucks on one seems very excessive and I myself wouldn't pay it. $300 bucks goes a long way on other things.

[heirfaus]

For example when I see a datsun tracked on a regular basis and the paint/windshield gaskets are cracking/warping I know the car is flexing. No formulas required.

 

Did you see the link I posted up a few posts ago. The post by Bert Vorgon that said on the jig the area that flexed was the door opening. I wonder if it is the A pillar that causes this.

 

Math and science is all good and well but I don't need it to tell certain things.

 

Well, yes and no. It's obvious if paint and gaskets are cracking that something is wrong, but it would be nice to use math and science to determine whether it's the A pillar or the strut towers causing the problem. Since the only provided testing shows door frame flexing I would imagine the hard cold facts point to the A pillar. BTW did you try and put a strut bar in? Did that cure all of the paint and gasket problems? Also, you keep saying Datsun's. Are you talking about 510's? I guarantee you 510 and Z cars will flex in different areas.

 

What it comes down to though is ALL cars flex if pushed properly on a track, that's just a fact.

 

Yes, I do agree, it's just finding the areas that flex the most and fixing those first that is important.

 

$300 bucks on one seems very excessive and I myself wouldn't pay it. $300 bucks goes a long way on other things.

 

Far too excessive! Good thing I didn't have to pay for it....and no it's not stolen.

 

I'm not trying to argue either. :) It's just when it comes to a project, it's better to put your money in the places that need it most. Even if a 510 benefits from a strut bar on some small level it should definitely be put at the end of the list. I think people are inclined to buy them because they are cheaper and easier to install compared to other suspension upgrades but don't realize it isn't a wise dollars-to-handling ratio type of purchase.

[DISLEXICDIME]

you can only use math and science if you can figure out a way to add metal fatigue from flexing and rust

[HRH]

You do know that cars are built on 100% math and science and deciding what improvements need to be made is 100% math and science. But hey, who needs numbers and accurate testing....

 

 

 

I'm very curious how you know this. What particularly warrants a strut bar on a 510? If you know something others don't, please do tell, because I have a real carbon fiber strut bar in my garage I haven't put on, but if you can give one example that is credible I will think about using that 300 dollar paper weight.

 

Also judging from the stuff HRH has said on his web page I would suspect things he says anyway....

 

 

 

 

Yes, two different things. The strut bar keeps the suspension geometry accurate on cars that flex too much and the sway bars help to keep the car flat in the corners. :)

 

Okay, Mr. Doubting Thomas, here's a news flash: The 100% mathematically designed chassis, extensively tested in the 1960s, is 40 years old and is significantly less strong than it was when it was built.

 

Moreover, ALL chassis' flex. What happens in ANY strut based monocoque structure commonly known as a unibody is the front struts attempt to pull apart the chassis when loaded to extreme measures, as found in ANY sort of racing or hard abuse.

 

Take a look at any car that is raced but not a tube frame. You'll find most of them have a strut tower bar to keep the structure from trying to pull itself apart. Race cars don't usually have them, because (surprise,surprise) the cages they're built on are ten times stronger than the original car, to not only protect the driver, but the make an exceptionally rigid chassis that flexes as little as possible to allow for greater control.

 

I don't care what may or may be on my website, and I'm sure some of it is inaccurate, but why don't you go read a chassis engineering book like the one that's on my shelf, and perhaps you'll understand.

[heirfaus]

Okay, Mr. Doubting Thomas, here's a news flash: The 100% mathematically designed chassis, extensively tested in the 1960s, is 40 years old and is significantly less strong than it was when it was built.

 

Moreover, ALL chassis' flex. What happens in ANY strut based monocoque structure commonly known as a unibody is the front struts attempt to pull apart the chassis when loaded to extreme measures, as found in ANY sort of racing or hard abuse.

 

Take a look at any car that is raced but not a tube frame. You'll find most of them have a strut tower bar to keep the structure from trying to pull itself apart. Race cars don't usually have them, because (surprise,surprise) the cages they're built on are ten times stronger than the original car, to not only protect the driver, but the make an exceptionally rigid chassis that flexes as little as possible to allow for greater control.

 

I don't care what may or may be on my website, and I'm sure some of it is inaccurate, but why don't you go read a chassis engineering book like the one that's on my shelf, and perhaps you'll understand.

 

Wow I don't even know where to start...nor do I want to. Not really interested in arguing. I just hate seeing inaccurate and un-substantiated advice advice.

Edited September 3, 2009 by heirfaus

[fo0manchu]

wow, people got sensitive quick in this one.

I got a strut bar. Works good, its triangulated though and cost about 20something bucks to make and I think it looks good. Word.

[HRH]

Wow I don't even know where to start...nor do I want to. Not really interested in arguing. I just hate seeing poor quality advice.

 

I still have not heard or seen any evidence that even begins to lean towards a 510 needing a strut bar. So have fun with your chassis book. I hope you and it have a great relationship. Oh yeah I have a book that's titled "Make a million dollars at your job" on my shelf. I guess that applies to everyone :D

 

I was merely trying to suggest that instead of making ass-hat comments about poor quality advice without basis, maybe you should read a similar book as evidence of chassis reinforcement, thus necessitating a strut tower bar. Furthermore, if you read what I posted, I explained exactly why a strut tower bar is a good idea, see the part about strut towers trying to move apart under load. Do you need a strut tower bar? No. Would it help? Yes.

 

I am curious, have you ever actually raced a 510 in a competitive event with other vehicles? Given the nature of your arguments, I would imagine not.

 

By the way, Z cars and 510 flex in similar points due to the construction of the car . For instance, when the frame rails degrade and you turn left in a Z car and it goes right instead due to flex. Can happen on a 510 too, although not as likely.

[heirfaus]

you can only use math and science if you can figure out a way to add metal fatigue from flexing and rust

 

Well, I guess, assuming you have rust problems. I have almost zero rust. And even then, the realm thread I link has a post about testing the strut towers on a car so rusted it almost isn't warranted as a DD and the flex was negligible. Jigs pipes and tape measures are all you need. You twist the metal and fix the weak points. I'm not proposing that the car is perfect. All I'm saying is with some simple math and testing you can find the weak areas. Then you know what to focus on. Like said earlier, there has been a 510 that has gone through a frame twisting test by one of the more notable 510 shops and the test doesn't conclude the strut towers need bracing. If people want to use the "seat of the pants" method to warrant bracing, well heck, go for it, I just choose to trust the numbers.

Edited September 3, 2009 by heirfaus

[Cuts metal like mad]

I believe what HRH is refering to is not chassis flex, but rather the strut towers busting the spot welds and ripping away from the inner fender well. Under extreme circumstances this does happen, I have seen first hand the results. I don't remember the cause... its been several years, but seam welding will serve the same purpose in this, that a strut bar would...

 

Then again, I may be misunderstanding.

[heirfaus]

I was merely trying to suggest that instead of making ass-hat comments about poor quality advice without basis, maybe you should read a similar book as evidence of chassis reinforcement, thus necessitating a strut tower bar. Furthermore, if you read what I posted, I explained exactly why a strut tower bar is a good idea, see the part about strut towers trying to move apart under load. Do you need a strut tower bar? No. Would it help? Yes.

 

I am curious, have you ever actually raced a 510 in a competitive event with other vehicles? Given the nature of your arguments, I would imagine not.

 

By the way, Z cars and 510 flex in similar points due to the construction of the car . For instance, when the frame rails degrade and you turn left in a Z car and it goes right instead due to flex. Can happen on a 510 too, although not as likely.

 

Your right I haven't raced, I just listen to the guys who have been for 10,20,or 30 years and HAVE had testing done. I have been building up my 510 for four years and it is nearing track ready finally.

 

My comment about the book was merely to point out that a Ferrari and a Geo metro are not the same. Just saying that you should buy a strut bar because the chassis book says it's good is like saying every car warrants buying a strut bar which isn't true. Yes it will help on some cars, just like two different members have noted early Hondas have a lot of flex, but I wouldn't put one on a Ferrari if it didn't need on. Likewise, why put one on a 510 if it didn't need one. You shouldn't just put parts on because they are available.

 

Reading a chassis book will not tell us whether a 510 needs a bar. I fully understand bracing and when it is appropriate, but I don't understand adding weight to a car who's prime value is it's low weight when the weight has been show to have no benefit. I know, I know you say it does, BUT you have nothing to prove it and we have 2 community members that have disproved it......

 

Like I said I'm not trying to argue so if you have any sort of evidence to suggest the 510 needs one I would really love to hear the information.

Edited September 3, 2009 by heirfaus

[heirfaus]

I believe what HRH is refering to is not chassis flex, but rather the strut towers busting the spot welds and ripping away from the inner fender well. Under extreme circumstances this does happen, I have seen first hand the results. I don't remember the cause... its been several years, but seam welding will serve the same purpose in this, that a strut bar would...

 

Then again, I may be misunderstanding.

 

Yeah I don't think he is talking about that only because it sounds like he is saying that every car should have a strut brace....but who knows maybe that's his angle....

[DISLEXICDIME]

Well, I guess, assuming you have rust problems. I have almost zero rust. And even then, the realm thread I link has a post about testing the strut towers on a car so rusted it almost isn't warranted as a DD and the flex was negligible. Jigs pipes and tape measures are all you need. You twist the metal and fix the weak points. I'm not proposing that the car is perfect. All I'm saying is with some simple math and testing you can find the weak areas. Then you know what to focus on. Like said earlier, there has been a 510 that has gone through a frame twisting test by one of the more notable 510 shops and the test doesn't conclude the strut towers need bracing. If people want to use the "seat of the pants" method to warrant bracing, well heck, go for it, I just choose to trust the numbers.

 

all these cars have rust you just cant see it !:) all the dimes i have seen cut up or cut open my self have had rust in places you could only find by cutting open the cars.

[heirfaus]

all these cars have rust you just cant see it !:) all the dimes i have seen cut up or cut open my self have had rust in places you could only find by cutting open the cars.

 

Alright you got me there ;) I guess I was just more commenting on the area's of this topic :)

[FujiyamaMama]

Wow...

[HRH]

Reading a chassis book will not tell us whether a 510 needs a bar. I fully understand bracing and when it is appropriate, but I don't understand adding weight to a car who's prime value is it's low weight when the weight has been show to have no benefit. I know, I know you say it does, BUT you have nothing to prove it and we have 2 community members that have disproved it......

 

Like I said I'm not trying to argue so if you have any sort of evidence to suggest the 510 needs one I would really love to hear the information.

 

Anyone who argues the lack of evidence of simple MECHANICAL ENGINEERING principles, when told to examine sources other than their own bias, is asking questions without listening. And you're talking about adding weight, what the hell. A tubular strut tower bar might weigh 5 pounds. Besides that, if you wanted the lightest chassis, you would have made a tube frame B13 Sentra racecar with an L16 since they're way lighter than a 510 and surprise, they're a better chassis design. I love my 510 but it IS a 40 year old concoction.

 

 

Think of the front end of the car as the box that it is. Which sides are closed, or have some sort of sheer panel? The firewal is one big shear panel, that's strong. The front core support is weak, but not asked to bear much load. If you look at the car with the hood open, you'll note it's a big square, with nothing in the way. However, the bottom square is held together by a big crossmember, which keeps that from moving. So you have the bottom of the box, the rear (firewall) of the box, and the sides of the box (inner fenders and fenders) all having some sort of reinforcment except the top where the hood is.

 

That said, a gigantic open square has no strength, although it is relatively insulated by the other features of the nose of the car. Regardless, it certainly does help to box that side, by attaching a strut tower bar. As I've said before, you don't absolutely NEED it, but it's a great idea.

 

I would be curious to see the twisting videos of the 510 chassis, I think that's great knowledge to know the weak points. What it doesn't take into account is compression and rebound movement of the strut towers, particularly as in rallying. When your suspension bottoms out, all that force gets transferred to the chassis, which resultingly moves.

 

Seam welding certainly will help and is also a good idea, but tying together the suspension points is an excellent way to retain the rigidity the car has at static, and then apply it when beating the piss out of a 510. You'll note I don't have a strut tower brace on my 510 yet. I will have one before too long, probably very similar to Foomanchu's design, which I'm sure it quite effective.

 

By the way, since you've been building your 510 for four years, let me tell you what I've been doing. A, I've autocrossed for the last 6 years, including two 2nd places season trophies in CSP class, B, have pit crewed for professional 510 and Miata racers (ICSCC) in my community, C, have a working relationship with my fabricator who builds Datsun, MG, Formula Ford racecars, and knows a damn site more than most people. But at this point, after dozens of examples of engineering basics, if you want to piss on strut tower bars and the advice of those who just possibly might know more than yourself, go right ahead. Maybe in another few years you'll be racing and then you can answer your own question.

[Jesse C.]

What is it doing?

And maybe I do wanna look cool... -.-

 

Dude, you own a 510, you already are cool! Aayyy!

[Jesse C.]

yeah, who needs a sway bar anyways :o

 

hey jesse, you dont have a welder do you? :o

 

Personally, no, but I do have access to a few of them! :)

 

Mig, Tig, Stick and even a Carbon Cutter.

[Jesse C.]

Ok, throwing my two crazy cents into this mess.

 

If you truly want to stiffen up the nose, then stitch weld the seams and tie the towers to the firewall. Side to side flex can be eliminated or reduced with the strut brace, but, you still have it flexing rearwards to a degree. Just take a look underneath the hood of a Ford Shelby Mustang GT 350 and you will not only see a strut bar but a Monte Carlo bar triangulating the front end.

 

Is all this necessary on a street driven car, not really. Unless you are The Transporter and then you would not be driving a 40yr. old Jap Bucket! :lol:

 

Anyhoo, I am putting one on mine because I have one already and they look kinda neat!

[datsun8]

+1 on Heirfas acting like an ass hat.

 

fuji- i was talkin' about the car in HRH's sig, dirt jumpin' needs stiff chassis....well not if you ask heirfas.....i was makin' a joke. he was kind enough to point out how technically incorrect I was.....:)

[72240z]

Don't start flaming bullshit. A few of us just didn't agree and now it will pass.

[heirfaus]

Anyone who argues the lack of evidence of simple MECHANICAL ENGINEERING principles, when told to examine sources other than their own bias, is asking questions without listening.

 

A piece of 18 guage steel bends easily. A piece of 1/4 steel is much more difficult to bend. I just saying that unless you test the front end how do you know the actual level of stiffness and how do you know what bracing is needed.

 

What it doesn't take into account is compression and rebound movement of the strut towers, particularly as in rallying. When your suspension bottoms out, all that force gets transferred to the chassis, which resultingly moves.

 

I whole heatedly agree with you, but almost none of use are bottoming out our suspensions because we drive on the roads or tracks.... unless it is very poorly setup in which case a strut bar is the least of concerns.

 

By the way, since you've been building your 510 for four years, let me tell you what I've been doing. A, I've autocrossed for the last 6 years, including two 2nd places season trophies in CSP class, B, have pit crewed for professional 510 and Miata racers (ICSCC) in my community, C, have a working relationship with my fabricator who builds Datsun, MG, Formula Ford racecars, and knows a damn site more than most people. But at this point, after dozens of examples of engineering basics, if you want to piss on strut tower bars and the advice of those who just possibly might know more than yourself, go right ahead.

 

Cool, I bet that has been fun!:) But like I said earlier, I am not responded to your posts with my small knowledge base of the subject but from others with far more experience.

 

well not if you ask heirfas.....i was makin' a joke. he was kind enough to point out how technically incorrect I was.....:)

 

didn't notice the lol'ing first time... may bad

 

Don't start flaming bullshit. A few of us just didn't agree and now it will pass.

 

Agree to disagree I guess. HRH if you put on a strut bar and start getting first place trophies in your auto crosses, well, more power to you. In fact I hope it does help you.

[FujiyamaMama]

LOL I was honestly not expecting this! My brother has a honda and he was speaking from honda experience when recommending it to me but I honestly think he's being a bit over zealous because I'm not much for taking my car to the track.

[heirfaus]

And I couldn't resist,

I guess this is me :D

 

[datsun8]

no sweat heirfaus. we gotta stay cool as datsun people.

[ichorid]

Fuji, maybe I missed the thread, but what do you have in the car? honestly if you're not smashing serious rear wheel horsepower. just get the car looking good. Get front rear swaybar upgrades. tires, (REAL TIRES), rims, etc. 150-300 bucks on a strut tower bar is super end game style car equipment. (if even needed)

 

http://www.youtube.com/watch?v=bJz3OP_RW0o&feature=player_embedded

 

that level of end game style equipment.