Are aftermarket thicker sway bars really worthwhile for a street car?
Is that for sale, or can I borrow it?
04-30-06, 09:41 AM
#27
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Originally Posted by TRISPEEDFD3S
HAHHAHAHAHAHAHAHAHAHAHAHAH.......again, HAHAHAHAHAHA funny man... I love this forum! Tyler again with killer advice too!
04-30-06, 09:49 AM
#28
Originally Posted by jsplit
Yes I was trying to keep my post as irrelevant as humanly possible with absolutely no technical data.
04-30-06, 11:34 AM
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I too agree with Rynberg. The thicker the bars the more the car acts like a solid rear axle over bumpy roads.
I have the PFS springs and bars and they are by no means extreme, but ride quality is compromised on crappy roads.
I have the PFS springs and bars and they are by no means extreme, but ride quality is compromised on crappy roads.
05-01-06, 02:37 AM
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Sounds like I will be in the minority here. I have had two FDs, a 93 R1 and 93 Touring and both had considerable understeer problems for my taste.
Just last week I did some calculations from the stock sway bar sizes on my present Touring model. According to those the 1.13" front bar has a rate of 720 lbs/inch and the 0.680 rear bar has only 220 lbs/inch. I used several sets of lowering springs between the two cars, settling for the RBs with the R1 and choosing the Tein SS for the Touring.
You have to look at your spring rates before deciding on roll bar rates. I see some incredibly ignorance on spring and bar rates out there. Most manufacturers do not even seem to find it important to list those rates, apparently figuring that the customer would not understand them. I'd like to know who many FD owners actually know their stock or aftermarket spring and bar rates? Last Friday I called RB to ask about the rate for their tubular rear bar. I held for a long time until the sales clerk went to see the RB Engineer who still did not know it, even worse, he did not even know the wall thickness of the bar, from which I offered to calculate the bar rate. They promised to call me back with the info.... maybe they will... Hmmmm... wonder how well that puny looking tubular bar works with their 1 1/4 inch solid front bar which, if considering the stock bar measurements (arm length, bar length, diameter) would have over 1000 lbs/inch rate?
The few rates for springs that I see out there are just way over the top in rating. I see F & R spring rates in excess of 600 - 700 lbs/inch which just destroys the ride and compliance for road cars as light as the FD, unless your road surfaces are glass smooth like the German Autobahn. Heck the max spring rate that I had ever tried on my GT race car was 550 lbs on the front and around 450 on the rears and I found that too stiff for even the race track.
My preference for road going or, occasional track cars is a relatively soft set of springs enough to keep you off the bump stops and heavy bars front and back to keep the roll in check and to make transitions much sharper. I had only driven one other FD which must have had some horrificly high spring rates, making it feel like that the car had no suspension at all. Crashing over any and all road imperfectons it was simply undrivable but, it was cool looking when parked, sitting that low over its 18" rims.
I was kind of torn recently between the RB springs that are not that much stiffer than stock and the Teins, that are around 430 - 325 F & R. I chose the Teins figuring that I wanted a car with a bit lower look but, I still might switch to the RBs eventually. The Teins are just a bit too stiff for these bad CA roads, upsetting the handing when going over cracked, pavement.
For both FDs I kept the front bar rates around stock (700 lbs but, using poly bushings). For rear bars for both FDs I ran close to 600 lbs bars and they worked perfectly for my driving style both street and track. I am very sensitive to understeer and hate it with a passion. A tiny bit is good for safety but, even moderate amounts make me feel like I am driving a pig that pushes dirt with its nose. (BTW - An other important variable is the front vs rear rideheight in setting up for over or understeer)
After seeing so many varied opinions on perceived understeer vs. oversteer I guess, you just going to have to try various combinations and see what suits your driving style and what gives you the quickest lap times on the track. For me, there was never a doubt that I was much faster with high rear bar rates but, I had a very smooth driving style when it came to transitioning the car. I would start turning the steering wheel almost unperceivably ways before the actual corner, making sure that the chassis transition was as smooth as possible vs. people with more abrupt transition styles who tend to "throw" the car into a cornering transition. Such differences in driving style alone would account for major differences in perception as to handling traits.
Just last week I did some calculations from the stock sway bar sizes on my present Touring model. According to those the 1.13" front bar has a rate of 720 lbs/inch and the 0.680 rear bar has only 220 lbs/inch. I used several sets of lowering springs between the two cars, settling for the RBs with the R1 and choosing the Tein SS for the Touring.
You have to look at your spring rates before deciding on roll bar rates. I see some incredibly ignorance on spring and bar rates out there. Most manufacturers do not even seem to find it important to list those rates, apparently figuring that the customer would not understand them. I'd like to know who many FD owners actually know their stock or aftermarket spring and bar rates? Last Friday I called RB to ask about the rate for their tubular rear bar. I held for a long time until the sales clerk went to see the RB Engineer who still did not know it, even worse, he did not even know the wall thickness of the bar, from which I offered to calculate the bar rate. They promised to call me back with the info.... maybe they will... Hmmmm... wonder how well that puny looking tubular bar works with their 1 1/4 inch solid front bar which, if considering the stock bar measurements (arm length, bar length, diameter) would have over 1000 lbs/inch rate?
The few rates for springs that I see out there are just way over the top in rating. I see F & R spring rates in excess of 600 - 700 lbs/inch which just destroys the ride and compliance for road cars as light as the FD, unless your road surfaces are glass smooth like the German Autobahn. Heck the max spring rate that I had ever tried on my GT race car was 550 lbs on the front and around 450 on the rears and I found that too stiff for even the race track.
My preference for road going or, occasional track cars is a relatively soft set of springs enough to keep you off the bump stops and heavy bars front and back to keep the roll in check and to make transitions much sharper. I had only driven one other FD which must have had some horrificly high spring rates, making it feel like that the car had no suspension at all. Crashing over any and all road imperfectons it was simply undrivable but, it was cool looking when parked, sitting that low over its 18" rims.
I was kind of torn recently between the RB springs that are not that much stiffer than stock and the Teins, that are around 430 - 325 F & R. I chose the Teins figuring that I wanted a car with a bit lower look but, I still might switch to the RBs eventually. The Teins are just a bit too stiff for these bad CA roads, upsetting the handing when going over cracked, pavement.
For both FDs I kept the front bar rates around stock (700 lbs but, using poly bushings). For rear bars for both FDs I ran close to 600 lbs bars and they worked perfectly for my driving style both street and track. I am very sensitive to understeer and hate it with a passion. A tiny bit is good for safety but, even moderate amounts make me feel like I am driving a pig that pushes dirt with its nose. (BTW - An other important variable is the front vs rear rideheight in setting up for over or understeer)
After seeing so many varied opinions on perceived understeer vs. oversteer I guess, you just going to have to try various combinations and see what suits your driving style and what gives you the quickest lap times on the track. For me, there was never a doubt that I was much faster with high rear bar rates but, I had a very smooth driving style when it came to transitioning the car. I would start turning the steering wheel almost unperceivably ways before the actual corner, making sure that the chassis transition was as smooth as possible vs. people with more abrupt transition styles who tend to "throw" the car into a cornering transition. Such differences in driving style alone would account for major differences in perception as to handling traits.
Last edited by axr6; 05-01-06 at 02:48 AM.
05-01-06, 03:23 AM
#33
axr6, another good read.
when it comes to suspension modifications, there is no single magic setup that will work for everyone. driving styles differ nad so the suspension needs and adjustments will differ to each driver. look at team drivers, they will have (most often)very different setups even though they are driving the same car in every other aspect.
when it comes to suspension modifications, there is no single magic setup that will work for everyone. driving styles differ nad so the suspension needs and adjustments will differ to each driver. look at team drivers, they will have (most often)very different setups even though they are driving the same car in every other aspect.
05-01-06, 08:42 AM
#35
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Originally Posted by GoodfellaFD3S
Are aftermarket thicker sway bars really worthwhile for a street car? Reply to Thread
Will you notice a difference in the car with bigger bars? Yes. Does that difference make the car "better"? That's up to you. To me firmer is not better, it's just different. The conventional widsom around here always thinks that if the part isn't stock and it somehow makes the car "different" then that equals better. I think that's nuts. What counts in any mod is the actual payoff and in this case there's no real payoff until you go to the track.
Driving on the road you'll have no idea of the real balance anyway. The balance for a given setup at 7/10 or 8/10 is often completely different than 10/10 and you won't even approach the limit without being at the track.
05-01-06, 09:00 AM
#36
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Originally Posted by DamonB
IMO no. The Fd is already a wonderfully handling chassis. Sometimes we forget that and you have to go drive some other cars to be reminded
Will you notice a difference in the car with bigger bars? Yes. Does that difference make the car "better"? That's up to you. To me firmer is not better, it's just different. The conventional widsom around here always thinks that if the part isn't stock and it somehow makes the car "different" then that equals better. I think that's nuts. What counts in any mod is the actual payoff and in this case there's no real payoff until you go to the track.
Driving on the road you'll have no idea of the real balance anyway. The balance for a given setup at 7/10 or 8/10 is often completely different than 10/10 and you won't even approach the limit without being at the track.
Will you notice a difference in the car with bigger bars? Yes. Does that difference make the car "better"? That's up to you. To me firmer is not better, it's just different. The conventional widsom around here always thinks that if the part isn't stock and it somehow makes the car "different" then that equals better. I think that's nuts. What counts in any mod is the actual payoff and in this case there's no real payoff until you go to the track.
Driving on the road you'll have no idea of the real balance anyway. The balance for a given setup at 7/10 or 8/10 is often completely different than 10/10 and you won't even approach the limit without being at the track.
.My FD is going to be up on the lift this week for a TII diff and 4.3 gear install, so while it is up there I'm going to inspect all of my bushings (to include the sway bar bushings). Ray is having a big sale on all of them, so I figure now is the time to buy them if I need 'em.
Btw, I hope you're getting sleep these days, what with the new addition to the household
.Rich
05-01-06, 09:23 AM
#37
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Originally Posted by GoodfellaFD3S
Btw, I hope you're getting sleep these days, what with the new addition to the household
.Rich
05-01-06, 09:43 AM
#38
I never thought the car rolled excessively with the stock setup. That being said, Im most likely on my way to a full RB set or at least an RB rear bar(which is on the car currently). Riding on s-techs and GAB's. This is a great thread guys. How about some comparisons of different sway bars?
05-01-06, 04:12 PM
#40
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Rich. you started what has turned out to be an excellent thread.
i especially applaud AXR6 and agree w most everything he posts. i also agree w DamonB.
there are a few things worth adding....
a common misunderstanding is that less body roll means less lateral load transfer.
not so.
stiff springs and bars do not decrease lateral load transfer.
lateral load transfer (in a corner) is EVIL. it overloads the outside tires and deloads the inside tires. ideally you want equal load on outside and inside. that's why lower (ride height) is FAST. lower means less lateral weight transfer.
the more stiffly you spring the car or the more bar you put in the car the FASTER the load laterally transfers.
if you want to experience a too stiffly sprung chassis pump your tires up to 75 psi and go for a drive. it won't be pretty.
going fast, driving on the limit is all about chassis feedback. the FEEL of the point where the limit is reached. shorten the communication time, increase the difficulty of driving at the limit. really stiff chassis are like driving on ice. do any of us think we can feel where the limit is on glare ice?
DamonB makes a great point when he posts that the car may feel faster w alot more roll stiffness as it immediately responds to steering input but if too stiffly sprung it may not be able to be driven near the limit.
another aspect of roll is dynamic suspension geometry. the FD is a true racecar geometry-wise. it has just the right amount of negative camber gain on bump so body roll does not create positive outside wheel camber as on most pretend "sportscars."
sway bar rates should be viewed as to how they relate to spring rates and corner weights as well as wheel size. if you already have stiffer springs, and i like 450 front 350 rear max, then you should consider how much additional bar rates to add. tire/wheel width is an important factor when considering bar size. i run 8.5 front to maintain zero scrub radius and 10 inch in the rear for traction and to counteract the natural front engine rear drive oversteer tendancy.
bars play a roll in longitudinal trim. too much rear bar and too much oversteer.
tire pressure is extremely important in the equation. soft in the rear.... 2 to 3 pounds less air in the rear. 30 front, approx 27 rear.
that all said, i do think my fd could use a bit more bar and will be making a tri point type bar sometime this summer.... if you are handy you just select the straight (light) hollow tube from Stock Car Products, around $90, a set of aluminum trailing arms about $90 and get fabbing. i ran that setup on my real racecar and it is nice as it is really light and adj both by switching bars (same O D, diff wall thickness) as well as the usual arm length options.
i will probably not need anything more in the rear than the OEM bar.
howard coleman
i especially applaud AXR6 and agree w most everything he posts. i also agree w DamonB.
there are a few things worth adding....
a common misunderstanding is that less body roll means less lateral load transfer.
not so.
stiff springs and bars do not decrease lateral load transfer.
lateral load transfer (in a corner) is EVIL. it overloads the outside tires and deloads the inside tires. ideally you want equal load on outside and inside. that's why lower (ride height) is FAST. lower means less lateral weight transfer.
the more stiffly you spring the car or the more bar you put in the car the FASTER the load laterally transfers.
if you want to experience a too stiffly sprung chassis pump your tires up to 75 psi and go for a drive. it won't be pretty.
going fast, driving on the limit is all about chassis feedback. the FEEL of the point where the limit is reached. shorten the communication time, increase the difficulty of driving at the limit. really stiff chassis are like driving on ice. do any of us think we can feel where the limit is on glare ice?
DamonB makes a great point when he posts that the car may feel faster w alot more roll stiffness as it immediately responds to steering input but if too stiffly sprung it may not be able to be driven near the limit.
another aspect of roll is dynamic suspension geometry. the FD is a true racecar geometry-wise. it has just the right amount of negative camber gain on bump so body roll does not create positive outside wheel camber as on most pretend "sportscars."
sway bar rates should be viewed as to how they relate to spring rates and corner weights as well as wheel size. if you already have stiffer springs, and i like 450 front 350 rear max, then you should consider how much additional bar rates to add. tire/wheel width is an important factor when considering bar size. i run 8.5 front to maintain zero scrub radius and 10 inch in the rear for traction and to counteract the natural front engine rear drive oversteer tendancy.
bars play a roll in longitudinal trim. too much rear bar and too much oversteer.
tire pressure is extremely important in the equation. soft in the rear.... 2 to 3 pounds less air in the rear. 30 front, approx 27 rear.
that all said, i do think my fd could use a bit more bar and will be making a tri point type bar sometime this summer.... if you are handy you just select the straight (light) hollow tube from Stock Car Products, around $90, a set of aluminum trailing arms about $90 and get fabbing. i ran that setup on my real racecar and it is nice as it is really light and adj both by switching bars (same O D, diff wall thickness) as well as the usual arm length options.
i will probably not need anything more in the rear than the OEM bar.
howard coleman
05-01-06, 10:06 PM
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Originally Posted by howard coleman
that all said, i do think my fd could use a bit more bar and will be making a tri point type bar sometime this summer.... if you are handy you just select the straight (light) hollow tube from Stock Car Products, around $90, a set of aluminum trailing arms about $90 and get fabbing. i ran that setup on my real racecar and it is nice as it is really light and adj both by switching bars (same O D, diff wall thickness) as well as the usual arm length options.
howard coleman
howard coleman
Thanks for costing me some more money . Guess a racer will always be a racer. I told myself after selling my last race car, 2 years ago, that no more fast cars. Then, I said, OK, I'll just get my favorite of all fast street cars, the FD, and just keep it simple and comfy.
Right....
That is why I just got a set of racing seats that, uncomfortable as they may be, will save me around 35 lbs weight. Now, I see your tip on the hollow bars and aluminum arms and for that money that is a no brainer for weigh savings. I also used to use those bars for my race cars and on my first FD but, I was paying the custom price for them that were far more expensive. Wow, what a sucker I was.... How nice to have all this online info these days!
One thing I am noticing on their site is that their bar calculations are substantially different from my calculations which I obtained by using a proprietary software from a very reputable racing business that used to sponsor me for years. Now I got to find out which calculations are NOT correct?
Thanks
Albert
Edit: Just playing with their numbers. Looks like their table values agree with my calculations for the hollow bars, if I assume 0.25" wall thickness. I tried several diameters and all worked out to pretty close. The big difference is in the solid bar rates. I suspect that their solid bar rates are incorrect. Just not enough difference between the hollow and solid of the same diameter. Example 1.25 solid is 617 with an 8" arm and 553 with a hollow bar of the same specs. That difference is much too small to be correct. After all, substracting the solid material missing in the tube, there is a 3/4" more metal in the solid bar (Total wall thickness is 0.5").
Last edited by axr6; 05-01-06 at 10:25 PM.
05-01-06, 10:44 PM
#42
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Originally Posted by howard coleman
Rich. you started what has turned out to be an excellent thread.
.
Originally Posted by howard coleman
sway bar rates should be viewed as to how they relate to spring rates and corner weights as well as wheel size. if you already have stiffer springs, and i like 450 front 350 rear max, then you should consider how much additional bar rates to add. tire/wheel width is an important factor when considering bar size. i run 8.5 front to maintain zero scrub radius and 10 inch in the rear for traction and to counteract the natural front engine rear drive oversteer tendancy.
howard coleman
howard coleman
05-01-06, 10:59 PM
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Originally Posted by axr6
Edit: Just playing with their numbers. Looks like their table values agree with my calculations for the hollow bars, if I assume 0.25" wall thickness. I tried several diameters and all worked out to pretty close. The big difference is in the solid bar rates. I suspect that their solid bar rates are incorrect. Just not enough difference between the hollow and solid of the same diameter. Example 1.25 solid is 617 with an 8" arm and 553 with a hollow bar of the same specs. That difference is much too small to be correct. After all, substracting the solid material missing in the tube, there is a 3/4" more metal in the solid bar (Total wall thickness is 0.5").
Ouchhhh.... I ran out of edit time while still calculating in the above post. The above comparison for the hollow bars really apply for closer to a 0.125 wall thickness, not 0.25. Than the solid bar of 1.25" would have a full inch more metal to twist which corresponds to a value of 320 lbs in those tables. If I added onto the listed 617 value for a 1.25 solid bar, the combination would equal 937 lbs, which is much closer to my software calculations of 933 for that same bar. So, looks like their solid bar tables are way off.
05-01-06, 11:03 PM
#44
I just received mine for my RB ones for my FC. But riding in cars with them, the roll for our cars is signifigantly less. I also have JIC FLT-A2's so even when the sway bars, it should be all a matter of how you adjust your suspension, and sway bars, for the feeling
05-02-06, 07:57 AM
#45
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i believe that the Stock Car Products bar that is used by TriPoint is
part # 608 188 35 retail is $91.50
as i recall there are 3 wall thickness options (same 1.25 O D)... the 188 (above) denotes .188 wall thickness.
i would assume you would then buy two aluminum arms @ $42 each.
bend the arms, drill the arms deal w the bushings, links and there you are.
the TriPoint bar has a bunch of drilled holes for adjustment but i don't think most will work as you want the bar very close to the same location as the stock bar and you would very quickly get too much link angle. most of the adj would probably come from selecting the proper wall thickness.
don't forget on the FD that the factory got a little crazy w weight reduction on the on the Swiss cheese bar support so when you go to a higher rated bar you need to reinforce the swaybar mount.
a final comment as to spring rates... treat them seriously and w respect if you want to have a comfortable ride and go fast.
spring rates, and a sway bar is just a straight spring, are CUMULATIVE.
a 450 pound per inch spring at one inch of compression is a 900 pound spring at 2 inches and 1350 at 3 inches.
ditto for sway bar.
for every one inch of front bump wheel travel the FD spring compresses approx .6 of an inch. the front corner sprung weight is approx 750.
compare:
a 450 pound front spring.
at one inch of bump is 450 pounds that would be at 1.66 inches of WHEEL travel.
at 2 inches of bump is 900 pounds. at 3.32 inches of wheel travel.
flowed thru the geometry the wheel rate would be 260 at one inch of wheel travel and 520 at 2 inches. so far so good as we are not locked solid which we would be if the wheel rate equals or exceeds the corner weight. (not considering dynamic cornerweight transfer)
now add the other spring.... the sway bar.
in a corner you need to add the sway bar resistance to the spring resistance. the stock bar is 28 mm thick and effectively 35 inches long w 8 inch arms. i haven't done the calculation but it is significantly additive to the corner spring rate. it connects about 1.75 inches inboard of the spring which slightly blunts its rate...
albert is indicating that the stock 28mm bar is significantly stiffer than the springs... i would really like to know what the specs are on the stock swaybar but the key is that it functions like a spring in that it resists outside wheel compression in a turn.
so lets get some good numbers on the stock bar and figure out what rate would be optimum considering corner weight, suspension motion ratio and springs.
howard coleman
part # 608 188 35 retail is $91.50
as i recall there are 3 wall thickness options (same 1.25 O D)... the 188 (above) denotes .188 wall thickness.
i would assume you would then buy two aluminum arms @ $42 each.
bend the arms, drill the arms deal w the bushings, links and there you are.
the TriPoint bar has a bunch of drilled holes for adjustment but i don't think most will work as you want the bar very close to the same location as the stock bar and you would very quickly get too much link angle. most of the adj would probably come from selecting the proper wall thickness.
don't forget on the FD that the factory got a little crazy w weight reduction on the on the Swiss cheese bar support so when you go to a higher rated bar you need to reinforce the swaybar mount.
a final comment as to spring rates... treat them seriously and w respect if you want to have a comfortable ride and go fast.
spring rates, and a sway bar is just a straight spring, are CUMULATIVE.
a 450 pound per inch spring at one inch of compression is a 900 pound spring at 2 inches and 1350 at 3 inches.
ditto for sway bar.
for every one inch of front bump wheel travel the FD spring compresses approx .6 of an inch. the front corner sprung weight is approx 750.
compare:
a 450 pound front spring.
at one inch of bump is 450 pounds that would be at 1.66 inches of WHEEL travel.
at 2 inches of bump is 900 pounds. at 3.32 inches of wheel travel.
flowed thru the geometry the wheel rate would be 260 at one inch of wheel travel and 520 at 2 inches. so far so good as we are not locked solid which we would be if the wheel rate equals or exceeds the corner weight. (not considering dynamic cornerweight transfer)
now add the other spring.... the sway bar.
in a corner you need to add the sway bar resistance to the spring resistance. the stock bar is 28 mm thick and effectively 35 inches long w 8 inch arms. i haven't done the calculation but it is significantly additive to the corner spring rate. it connects about 1.75 inches inboard of the spring which slightly blunts its rate...
albert is indicating that the stock 28mm bar is significantly stiffer than the springs... i would really like to know what the specs are on the stock swaybar but the key is that it functions like a spring in that it resists outside wheel compression in a turn.
so lets get some good numbers on the stock bar and figure out what rate would be optimum considering corner weight, suspension motion ratio and springs.
howard coleman
05-02-06, 11:06 AM
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Originally Posted by howard coleman
albert is indicating that the stock 28mm bar is significantly stiffer than the springs... i would really like to know what the specs are on the stock swaybar but the key is that it functions like a spring in that it resists outside wheel compression in a turn.
so lets get some good numbers on the stock bar and figure out what rate would be optimum considering corner weight, suspension motion ratio and springs.
howard coleman
I've tried to PM you with the little Excel software that I use but, seems like I can not do attachements in PMs. So, please send me your e-mail address if you want to have this program. It is 10 years old and small so it won't clog up your e-mail. This one does sway bar, torsion bar and wheel rate calculations. I do not wish to post this software on the forum. Way back, when I got it from my sponsor it was with the understanding that it was only for my personal use.
Since you car contributing so much technical data to this forum I do not see much risk for sending it to you.
I originally got under the car to measure the bar and these measurements are close enough. I do have a very serious spine injury now (from hitting a tree, skiing) so I could not get contorted enough to be 100 percent with my tape but, it is close enough. The are some "S" bends in the arms and I tried to take that into account.
Bar length = 33"
Arm length = both sides 9.25"
Diameter = 1.130
According to my software this produces a rate of 590 lbs/inch.
In my initial posts I made a mistake as quoting the front stock bar as over 700 lbs as I used a different torsion bar formula and a shorter, 9" lenght for the arm.
From the site you quoted here using the 49-spline tubes the 1.31 and the 1.38 seem viable as replacements. I would also need to get the car on jack, wheels off, to see what length tube would work best with what kind of bend on the aluminum arms. If you have that info to share, that would be great.
Albert
axr6@earthlink.net
05-02-06, 11:25 AM
#47
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Just FYI.
Cheap solid bronze bushings for the 1.25" bars along with the thrust bearings I'm using:
https://www.rx7club.com/3rd-generation-specific-1993-2002-16/fd-tripoint-front-sway-bar-bushings-thrust-bearings-393342/
I looked into building a completely custom bar at length sometime ago and between Stock Car Products and Hoerr Racing you can find anything you need. Only problem with the FD is the extreme bends the arms require in order to clear the front tires at full lock.
I also made custom mounts for about $25 in materials. Just two metal plates with a steel tube between them. I cut the radiator mounts off the stock parts and welded them to these.
Cheap solid bronze bushings for the 1.25" bars along with the thrust bearings I'm using:
https://www.rx7club.com/3rd-generation-specific-1993-2002-16/fd-tripoint-front-sway-bar-bushings-thrust-bearings-393342/
I looked into building a completely custom bar at length sometime ago and between Stock Car Products and Hoerr Racing you can find anything you need. Only problem with the FD is the extreme bends the arms require in order to clear the front tires at full lock.
I also made custom mounts for about $25 in materials. Just two metal plates with a steel tube between them. I cut the radiator mounts off the stock parts and welded them to these.
05-02-06, 11:55 AM
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Originally Posted by DamonB
Just FYI.
Cheap solid bronze bushings for the 1.25" bars along with the thrust bearings I'm using:
https://www.rx7club.com/showthread.php?t=393342
I looked into building a completely custom bar at length sometime ago and between Stock Car Products and Hoerr Racing you can find anything you need. Only problem with the FD is the extreme bends the arms require in order to clear the front tires at full lock.
I also made custom mounts for about $25 in materials. Just two metal plates with a steel tube between them. I cut the radiator mounts off the stock parts and welded them to these.
Cheap solid bronze bushings for the 1.25" bars along with the thrust bearings I'm using:
https://www.rx7club.com/showthread.php?t=393342
I looked into building a completely custom bar at length sometime ago and between Stock Car Products and Hoerr Racing you can find anything you need. Only problem with the FD is the extreme bends the arms require in order to clear the front tires at full lock.
I also made custom mounts for about $25 in materials. Just two metal plates with a steel tube between them. I cut the radiator mounts off the stock parts and welded them to these.
Nice work. That is quite a radical bend in the arm. What did you use to make that bend? Also, what was your impression of the change? According to my calculations the 1 1/4 inch tubular with 0/125 wall thickness is actually softer than the stock bar. Naturally much depends on the arm length of the new setup. Of course, if you still used the stock bar with rubber bushings prior to replacement, I'd expect the change to be still "feeling" stiffer and much more precise, given the solid bushings.
You certainly took out an insurance when you built those sway bar mounting towers
. Thus far, I've just re-inforced the stock ones with some additional, strategic plates welded to the structure. See if it's going to hold up.The offer that I made to Howard stand to you as well, so if you want it, please send me you e-mail.
Thanks for the great info
Albert
Edit: Lately since I destroyed one artery to the brain in that ski accident I only get half the blood flow into the brain. So, I am a bit too fast with my typing finger and a bit too slow in comprehension.
Howard said that Tripoint used a .188 wall thickness and assume, 35" bar length. With that info, it appears that the bar rate with 9.25 long arms (same as standard) would be actually little higher than stock, 634 lbs/inch.
Variables shown below for the calc. "E" is the inside diameter of the tube for a .188 wall thickness.
A-35.000
B-9.250
C-9.250
D-1.250
E-0.874
634.23
Last edited by axr6; 05-02-06 at 12:09 PM.
05-02-06, 12:47 PM
#49
Lives on the Forum
Originally Posted by axr6
That is quite a radical bend in the arm. What did you use to make that bend?
As Howard pointed out the torsion tube can be readily sourced and they're cheap. Best I can tell the only parts Tripoint actually makes for their bar are the arms and the nice linkage where the droplinks connect to the front a-arms.
My mounts are certainly over built but it made the fabrication convenient to do it that way. I have a couple extra sets of the steel upper and lower plates with the holes in them to bolt to the chassis and accept the solid bronze bushings if you or Howard are interested; just tell me where to send them. All you'd need to do is weld a plain 1.5" square tube between the plates along with the old radiator mounts and voila: custom bar mounts.
The only hurdle in any bar project is the arms. I never built a bar from scratch because I couldn't justify spending the money when I already have one that is doing everything I need once I built new mounts. I would love to build an adjustable blade style bar but those pieces are very expensive:
http://www.hrpworld.com/index.cfm?fo...action=product
http://www.hrpworld.com/index.cfm?fo...action=product
05-02-06, 01:24 PM
#50
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Originally Posted by DamonB
Those are Tripoint pieces;
The only hurdle in any bar project is the arms. I never built a bar from scratch because I couldn't justify spending the money when I already have one that is doing everything I need once I built new mounts. I would love to build an adjustable blade style bar but those pieces are very expensive:
]
The only hurdle in any bar project is the arms. I never built a bar from scratch because I couldn't justify spending the money when I already have one that is doing everything I need once I built new mounts. I would love to build an adjustable blade style bar but those pieces are very expensive:
]
Yes, the arms will be the challenge.
I've just got off the phone with my old sponsor and he is very reluctant to put a very sharp bend into the aluminum arm. He claims that when he needs radical bends he uses heat and steel arms (as for their own Southwestern Tour car) and drills holes in them for weight. I'm not sure that I'd be happy with that. He invited me to go to his shop and look at a selection of aluminum arms that he has already bent but, since I moved to the hills, he is about a 3 hours drive one way. He also asked me to fax him a template for the bend to see if he can do it.
Now, I wonder if he did the bending on the original arms for my first FD or simply purchased it from Tripoint and passed on the cost?
I'd love to take you up on your offer for those tower pieces. I'll PM you with my address and info.
Thanks
Albert