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Rear Suspension Upgrade In Progress (Powdercoat Inside!!)

Discussion in 'Driveline' started by DSG2NV03, Jan 20, 2011.

  1. jrgoffin

    jrgoffin Been around... Established Member

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    Which is why it seems that bolting the empty cradle in first (when doing this job solo) is the way to go. Adding the pumpkin, axles, control arms, etc., afterward can't be any harder!
     
  2. Black Sex

    Black Sex Active Member Established Member

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    I took my IRS from the floor to being bolted in the car in less than 10 minutes using a tranny jack. It don't get any easier than that.
     
  3. Root1022

    Root1022 100 Shot, 1 Kill Established Member

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    Yup when I had my IRS I had a tranny jack and a lift (Ft. Hood has a DIY shop) made it 100% easier. I've done it on my back before to and hated it!
     
  4. DSG2NV03

    DSG2NV03 MUST HAVE BOOST!!! Established Member

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    Yea I would like to get one.. Gotta find a reason to get it now!!!

    I did 100 down the street and some low speed stuff. I really need to get it aligned because I have a front coil hitting the body.

    Yea, but it is still awkward to just put up there.. Might as well be loaded.

    Yea that is easy.. We had about an hour in it just to get it in the cups.. The rest was pretty easy.

    I would love to have a lift... garage isnt big enough for it yet but someday i will get one.
     
  5. 04screamingvert

    04screamingvert Member Established Member

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    Looks awesome! To see what you have done with the photos give me hope that one day I can do this mod myself as well. How much time do you think you have in it?
     
  6. ac427cobra

    ac427cobra FULLTILTBOOGIERACING.COM Staff Member Super Moderator

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    This statement would be true for a car recently converted to a stiff coil-over suspension. :read:

    But in this case, this is unfortunately a NVH misconception that MANY people have. Please don't think that I am trying to single you out because I'm not. I'm simply trying to explain what is really going on. Some people are under the mistaken impression that the Delrin control arm bushings and UHMW subframe bushings add elevated NVH levels in the passenger compartment. NOTHING COULD BE FURTHER FROM THE TRUTH!!!! There is hardly any increase in NVH through these components.

    The only component in this kit that noticeably elevates NVH levels are the front diff mounts. And the higher the speed, the faster the gears are being meshed together, which in turn would raise NVH levels to the maximum noise level. So the OP was correct in trying to spin them exceedlingly fast in order to make them generate the maximum noise.

    He stated he heard no difference in noise levels and if you read the FAQ on our site:

    FTBR Frequently Asked Questions

    you'd see we state that we get feedback from people that run the full gamut of NVH levels. We've heard from customers: "I hear no difference in NVH levels" to: "The NVH levels are elevated a little but it's hardly noticeable", to: "Yes, it's kind of loud but it's worth it", to: "OMG my wife can't stand it".

    It's a very subjective question to ask a group of people who vary greatly in opinions.

    :thumbsup::coolman::beer:
     
  7. DSG2NV03

    DSG2NV03 MUST HAVE BOOST!!! Established Member

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    Agree with Bruce here, the street is actually pretty smooth on the bimpies and mine is a little bit stiffer because of the 375/575 coilovers.
     
  8. Taz

    Taz Active Member Established Member

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    Bruce, please reconsider the above assertion, because it appears to me as if you have contradicted yourself. I my mind, “hardly any” means “some,” although the amount or degree is left unspecified. And if there is some, then the folks who believe there is an increase in NVH are not mistaken at all.

    Obviously, all bushings are there for isolation. Consequently, to replace any bushings, regardless of their locations, with those of a much higher durometer and not expect “some” increase in NVH is sheer fantasy. In reality an isolation/performance tradeoff accompanies all bushing swaps. Whether or not the increased level of NVH is acceptable is a personal matter.

    We all have different comfort levels and tolerance limits, and the point at which NVH becomes objectionable is different for each of us. In general, young, limber, testosterone-driven males are inclined to trade away much more isolation for the sake of sharpened suspension reflexes, than old farts like me.

    With that in mind, Ford used rubber bushings to achieve the broadest market appeal. I doubt that it cost the boys at Henry’s house any less to use rubber for their suspension bushings than it would have cost to use any of the other materials you mentioned, probably more, considering the vulcanization step required in the manufacturing process. Nevertheless, most folks find the level of NVH produced by any of the other materials objectionable, so Ford used rubber.

    Sure, we’re not “most folks,” not even us old farts. We’re more performance oriented, so we’re generally willing to trade away some of that cushy isolation for enhanced reflexes, but we still all have different tolerance limits. Furthermore, some of us have never lost sight of the fact that what’s good for a track car isn’t necessarily good for a street car. Setting up a street car too much like a racecar results in a rolling punishment box. That’s an indisputable fact.

    I genuinely believe that your bushing kits contain the highest quality components available, and I commend you for your commitment to excellence. By the same token, I think they are much more appropriate for a track car than a street car. Since my car is primarily a street car, although I do drive it at open track and auto-x events, and because of my personal preferences, I elected not to install any bushings with a durometer higher than that of polyurethane (aside from the Heim joints, which I despise for their complete lack of isolation, that are now located at various points). While I am aware of your position on poly, this material provides the best handling/isolation compromise for my tastes, and I have been using it for many years without any issues at all.


    First, perception, like tolerance, varies. It is impossible to make universal statements regarding what is noticeable and what is not. Most, especially the limber, twenty-something, testosterone driven members among us, will swear up and down that installing Max Motorsports C/C plates did not increase the NVH transmitted through their chassis, but I immediately noticed the increase when I installed mine. They’re still installed, because the increase was acceptable in that instance, but it was and is noticeable to me. The Max Motorsports website even includes a disclaimer to this effect.

    Second, it has been my personal experience that low speed driving on less than perfect streets is much more telling than high speed blasts, with respect to suspension characteristics. At 100 mph, wind and engine noises, alone, are enough to mask much NVH. Furthermore, suspension oscillations at high speed favor less compliant bushings and stiffer suspensions to a very large extent. Right now, my own suspension is right at the NVH tolerance limit for me at low speeds around town, but at 80 and above it’s divine. Absolutely perfect. Now, if I could just come up with a way to maintain that 80 mph speed around town and retain my driving privileges, I’d be all set. :lol1:


    In this respect, we are in complete agreement. I commend you on your candor.

    :beer::thumbsup:
     
  9. ac427cobra

    ac427cobra FULLTILTBOOGIERACING.COM Staff Member Super Moderator

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    When I say 'hardly any' I mean 'barely noticeable'. I'd be willing to bet you would not be able to tell the difference, riding as a passenger blindfolded, between a stock IRS and an IRS that has had only a Delrin control arm bushing change. The only difference would be the Delrin bushed IRS will be a 'smoother' ride because the shocks and springs won't be fighting the bound up OEM rubber control arm bushings. NVH differences will be virtually undetectable.

    When I say a 'smoother' ride I'm referring to this comparison of bound up OEM rubber control arm bushings:


    bound up OEM rubber IRS control arm bushings



    As compared to freely articulating FTBR Delrin IRS control arm bushings:



    no more bound up OEM rubber


    Rubber bushings are mass produced and cheap for manufacturers to use. They isolate NHV well but compromise suspension horrifically, particularly when loaded. That's why racers and performance minded people focus on removing rubber as a first and top priority.

    I would compare this comment to someone putting a Kenne Bell on their car and saying DAMN that thing is noisy, I'm not sure I'm happy with it! :read:

    The Delrin control arm bushings in the IRS cannot be compared to a CC plate on the front of the car. The CC plate is a direct vertical attachment to the chassis. In the rear, the car is being supported by the knuckle and the rear spring (non-coil-over application) and the Delrin control arm bushings are merely the articulation attachment point.


    Gear whine is gear whine. The slower the gears are meshing at lower speeds the less noise will be generated. At higher speeds db levels will increase as they mesh together faster and faster.

    A lot of factors come into play as you've stated. With the windows up, wind noise will not mask gear noise, windows down, yes.

    One item in particular that will mask elevated NVH levels is exhaust noise which is one of the things I list on our website:

    FTBR Frequently Asked Questions

    when discussing the raised NVH levels of the front diff mounts:

    Q: "How much increase in NVH will I see with this kit?"

    A: The change in NVH will hardly be noticeable with the exception of the aluminum front differential mounts. They are a tad on the noisy side. Worse if you have 4:10 gears. If you have an aftermarket exhaust that's loud, it will help mask the noise from the diff mounts. Some have used the sound deadening matting available at car stereo shops to minimize the sound. It's a self adhesive matting you put down on the floor pan right above the differential. It's called Dynamat and it's also available at Eastwood.

    Q: "How bad will the noise level be with 4:10's?"

    A: 4:10's are definitely going to raise the noise level particularly with the Aluminum front diff mounts. As mentioned above, if you have loud aftermarket exhaust, that will help. Some people put down Dynamat on the floorpan directly above the differential and that seems to help a lot. Some say it's noisy, and others have said it's not bad. It's like asking what the best beer is. You won't get the same answer from any two people.



    A few years ago I installed our kit in a customer's car and he had a pretty loud exhaust system. I could not hear ANY difference in NVH levels in his car after the install and neither could he.


    I try to explain what people should expect with this kit to the best of my ability. I can honestly tell you that we have had MANY people comment, as the OP has stated in post #75 in this thread, that he has heard no difference in NVH. Right away, I know he has to have a fairly loud exhaust to make this statement.

    We've also heard the majority of our customers say they can hear an elevated level of NVH but the complete transformation of performance and handling they have seen in their car after the installation of the kit makes it more than worth it putting up with a little additional noise.

    We've also had people say it's pretty loud and these are the people that most likely are still on stock exhaust or a pretty quiet aftermarket system. I suggest the Dynamatting procedure to these people.

    I think we've only had one or two people in the approximate 1,000+ kits we've sold to date say OMG I have to take those front diff mounts out of the car.

    :thumbsup::coolman::beer:
     
    Last edited: Feb 13, 2011
  10. Taz

    Taz Active Member Established Member

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    Fair enough. But I’d bet that you’d lose that bet, so what have we just accomplished? “Barely noticeable” is still “some,” which is not “none.” QED


    Yes, I’ve seen your videos, but I consider them unrealistic for two obvious reasons:

    (1) The range of motion in my car’s rear suspension is only a few inches. Your video shows someone trying to achieve what appears to be 4WD suspension travel with that IRS, which I think is rather absurd.

    (2) Just exactly how much influence is a “bound up” rubber bushing really going to exert on a 600 to 800 lb/inch spring and matched damper? I believe the contribution of rubber bushing to that equation is going to be negligible.


    Mass-produced bushings of any material are cheap for manufacturers to use. It’s all about the economy of scale. Ford and the other auto makers don’t use rubber because it’s cheaper. They use rubber for the reason I noted earlier: broader market appeal due to better isolation. They consider rubber the most suitable material to achieve that goal. As for the performance compromise, I’ve already noted that.


    That’s completely non sequitur. How you arrived at that analogy is beyond me. My point was that we all have different tolerance limits with respect to the level of NVH we consider acceptable, and young bones tend to be more forgiving than old ones.


    Again, you appear to have missed my point, so I’ll spell it out. I wasn’t trying to compare CC plates with Delrin bushings. My point was that for any given suspension mod, there are those who will swear up and down that there’s no difference in ride quality or isolation, when there is, in fact, a very real difference. Whether such an erroneous proclamation arises out of a lack of perception or an intentional effort to deceive or some other reason, it is nonetheless erroneous. Perception varies, but you can’t change objective, measurable reality.


    Yes, a lot of factors come into play. Tire noise increases with speed. Wind noise increases with speed, regardless of whether the windows are up or down. Engine noise increases due to higher RPM, etc. They are all additive with regard to the net masking effect, and they all increase with speed. (I’d be happy to loan you my SPL meter so you can confirm this.) But gear whine wasn’t the crux of my statement. (In fact, I don’t seem to have mentioned gear whine at all in the statement you quoted.) The statement you quoted was directed at the increase in overall suspension NVH, not elevated gear whine.

    Now, be truthful here. In your personal experience, when does a car with solid bushings sound the most like a bucket of bolts? When it’s ripping along at high speed, or when it’s bumping from one tar strip to the next at low speeds? The correct answer is the latter, not the former situation. That’s the point I was trying to make, and that’s the plain old reality of it. If this isn’t true for you, then you and I are obviously not sharing the same reality.


    So basically, it looks like you’re recommending loading up the car with sound deadener and/or masking the increased noise level with something even noisier, i.e. a loud exhaust. I think I’ll pass. Besides, reducing the noise level addresses only one aspect of NVH. It does nothing to counteract vibration and harshness, both of which are also elevated by less compliant bushings.


    ”Right away, I know he has to have a fairly loud exhaust to make this statement.”

    Exactly my point. You know as well as I that the noise level in his cabin has increased, but some other ambient noise is masking it. His perception is that his noise level hasn't increased, but that's not the reality of his situation.


    Just as I have said before, solid bushings are worth the accompanying increased NVH to some, maybe even many. From what I've read, most of your customers here on SVTP seem very satisfied, and your customer service appears second to none. Kudos to you for that. But I still don't think solid bushings are suitable for everyone. As I’ve already noted, and as you appear to agree, we all have different tolerance limits. We also have different needs, wants, and expectations where our cars are concerned.

    For those who need/want solid bushings, I believe yours is certainly the definitive solution. Nonetheless, I'd wager that, in addition to the few who bought your kit and removed it, there were many others who simply never bought it to begin with, because they anticipated that it wouldn’t suit them. Do you suppose that's possible? I certainly don't know 1000+ people, but I have numerous friends who would never seriously consider solid bushings for their street cars, plus two who tried them and couldn't live with them. I probably also know some folks who run them on the street and love them, but I can't think of one.

    Please don’t hurt me. I’m not trying to talk anyone out of buying your fine products. I’m just trying to point out that they do not enjoy universal appeal. But then, I doubt anyone makes a product that pleases all of the people all of the time.

    :beer::thumbsup:
     
  11. ac427cobra

    ac427cobra FULLTILTBOOGIERACING.COM Staff Member Super Moderator

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    Taz:

    Clearly you have your own opinion regarding our kit which is something you've never personally experienced.

    I'll let our satisfied customers that DO have experience with our kit voice their feelings regarding it.

    Sound fair enough!? :shrug:

    :thumbsup::coolman::beer:
     
  12. Taz

    Taz Active Member Established Member

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    Bruce, I've personally experienced plenty of solid bushings in my time. There's nothing magic about yours that would make their performance any different.

    If you choose not to address the points I made, that's fine.

    :thumbsup:
     
  13. ac427cobra

    ac427cobra FULLTILTBOOGIERACING.COM Staff Member Super Moderator

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    I'm pretty sure I've addressed all of your points already. :thumbsup:
     
  14. Taz

    Taz Active Member Established Member

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    As you like.

    :beer:
     
  15. Spoolx

    Spoolx Active Member Established Member

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    you gotta take the good with the bad, half the people that talk great about your kit have never experienced it either
     
  16. ac427cobra

    ac427cobra FULLTILTBOOGIERACING.COM Staff Member Super Moderator

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    That's a pretty easy explanation actually.

    When you're on an automotive internet message board and you hear two or three people praising a product that solved their problems, you hardly notice.

    When 25 or 50 people post about positive experiences regarding a particular product you start paying attention.

    When 100, 200 or more different people post positive experiences regarding a product, that product's support and their own personal experience, this convinces you there is No Doubt this is the product you will be looking at when you are finally sick and tired of wheelhop and ill handling characteristics of the OEM IRS.

    You need to look no further than my trader rating link:

    http://www.svtperformance.com/forums/itrader.php?u=6247

    Or our testimonials page on our web site where we list people's comments regarding our kit and support along with links to their threads and posts on internet message boards:

    FTBR Testimonials


    :thumbsup::coolman::beer:
     
  17. DSG2NV03

    DSG2NV03 MUST HAVE BOOST!!! Established Member

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    Hmm that was interesting.. Great point on both accounts. I enjoy the kit and it has made considerable different in the predictability of the rearend. I have full bassani exhaust with cats, so it is louder, but not crazy loud. I threw the tailpipe baffles in today, which cuts sound by a lot and still didnt hear an appriciatable difference in the rear end. This was both accounts of high speed and low speed garbage roads.
    So I guess I am glad mine turned out like it did. I was concerned about it being loud and I would be interested to hear this situation on other cars.

    P.S. Bruce's customer service is second to none!!

    Alex
     
  18. DSG2NV03

    DSG2NV03 MUST HAVE BOOST!!! Established Member

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    Sorry for the late response :bash:. I didnt really keep a tally of the time. I would install a few things and set it aside. Ask Bruce some dumb questions and back at it I would go. I did take my time and if something just wasn't as smooth as it should have been (or Bruce said it should of been) then I took it back apart, regrouped, and went back at it. I did have some time waiting for diff cover and the powdercoat to get done. If I were to slap a number on it. I would say 12-15 hours total labor. Again, I took my time and kept everything clean, organized.

    Alex
     
  19. 04MystiCobra

    04MystiCobra Tuning L&M heart Established Member

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    If you're in a rush you can easily get it done in one weekend.
    As Alex did, I also took my time and things went pretty smooth.
     
  20. RoyWoods

    RoyWoods New Member Established Member

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    Poly FTW, in mine and my kidneys humble opinion.
     

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