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BT Stiffening Plate Review

Discussion in 'Gen 2 Prius Accessories & Modifications' started by OUscarb, Mar 8, 2006.

  1. gilahiker

    gilahiker New Member

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    What I remember is a 3-year, 36,000 mile warranty I think (it's in the car, I'm at work). If the tire blows or has a failure atributable to manufacturing Toyota will replace it. If any of the above happens, or there is flat, call the number, they will tow it to a dealer and fix/exchange the tire (of course, you may have to pay the pro-rated cost of the wear). I guess you've gone a bit over 22,300 miles? If you also have the warranty, don't mention that you think your increaseed tire wear is because of the BT plate!

    note: edited for spelling!
     
  2. Presto

    Presto Has his homepage set to PC

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    Ah okay... I should've knew that the warranty wouldn't cover wear. Thanks for clarifying. :)
     
  3. ARiddle

    ARiddle New Member

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    I have a 2006 that was difficult (maybe scary) to drive at 65+ from day one.

    I replaced the tires with Michelin Hydroedges, added the BT Plate, and had the car realigned. Each modification resulted in a noticeable improvement in handling and lessened response to wind buffetting and road irregularities.

    I now absolutely love the way the car handles at speed now and I am entirely happy with my BT Plate installation and recommend it to my firends.
     
  4. windstrings

    windstrings Certified Prius Breeder

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    <div class='quotetop'>QUOTE(DaveinOlyWA @ Apr 12 2006, 06:54 PM) [snapback]238859[/snapback]</div>

    Same here... I thought my car drove great until I installed the plate... now when someone ask about my car and is interested in buying one... When I tell them how wonderful it handles.... my guilt forces me to mention the BT plate... "I also feel a bit embarrassed for Toyota, or rather my affiliation" in the sense that I shouldn't have to tell someone.... "Oh yes its an awesome car...but you have to buy an extra plate to make it drive like mine".

    I guess thats ok, but when someone thinks about spending 30K on a car and someone tells them they really need to buy a 160.00 plate to make it handle perfect.... that sheds a negative light on the whole car to the uninformed buyer, because it appears Toyota's workmanship is shabby since you have to modify a perfectly brand new car!

    Sorry to be so redundant, but I don't want to be misunderstood... the prius still amazes me all the time with its crafy workmanship, but to someone who doesn't know better..I'm always torn as to whether to even mention the BT plate for fear it will only confuse them and they will walk away unimpressed, yet I don't want them to miss out!
     
  5. YBLee

    YBLee Junior Member

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    Any thought to the possibility that by adding stiffness in this area, the BT plate could possibly cause stress points which will eventually cause stress fractures emminating from the outside of the 4-bolt pattern? Could the OEM plate have been designed to flex in community with the design of the frame in the same way wings of an airplane are designed to flex - if they didn't, they would break! From what I have read by all the positive posters, it does appear the BT plate does tighten up the frame/ride. I'm just curious as to how it will effect the frame over time - BUT, only time will tell I guess!

    One more comment: I ride BMW and Honda motorcycles and have done so for years. In general, after a new purchase, most riders begin to replace OEM parts and do add-ons to not only to personalize, but in many cases, improve the handling of the machines. Shocks, tripple tree stiffiners, tires - you name it. I used to believe that manufacturers were experts and perfect, then I became a manufacturer!
     
  6. windstrings

    windstrings Certified Prius Breeder

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    <div class='quotetop'>QUOTE(YBLee @ Apr 14 2006, 02:56 AM) [snapback]239629[/snapback]</div>
    Your last statement is true, but when a plate that is so easy to make can do so much it should be a factory correction.

    They view this and other sites and should be aware of the issue and so either deem it bunk or have other reasons.

    Your point about other things taking the stress is a valid point, but the frame that the BT plate fastens to is so strong, I doubt there would be any issues like that.... if so, I can't imagine Toyota would be secretly holding back such a plate for knowledge that the rest of the car is built so flimsy that it would crack.

    Your point is worth considering, but I dont' think is a worry.
     
  7. RonH

    RonH Member

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    <div class='quotetop'>QUOTE(YBLee @ Apr 14 2006, 04:56 AM) [snapback]239629[/snapback]</div>
    Your comment regarding fatigue reminded me of a comment I made at the time the BT was introduced but got lost in one of the site crashes. The stamped steel OEM brace does have one advantage: as long as you don't exceed the yield strength (ie bend it) steel can endure essentially infinite stress cycles (sans rust and corrosion, too). Aluminum (Al alloy actually) can't. After some large, but finite number of stress cycles, it will fracture. Saying it is aircraft grade aluminum alloy doesn't change that. Airplanes are frequently inspected looking for signs of stress related fractures. Saying race teams uses CNC machined aluminum parts doesn't change that, either. They'll crash before it fatigues! I'm not advocating everyone go out and look under their car every morning. I'm just pointing out some of the tradeoffs real consumer vehicle designers make.
     
  8. darelldd

    darelldd Prius is our Gas Guzzler

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    <div class='quotetop'>QUOTE(YBLee @ Apr 14 2006, 02:56 AM) [snapback]239629[/snapback]</div>
    Indeed! There is nothing that can't be improved in some fashion! I take issue with those who say, "the Prius is PERFECT - why would you modify anything on it?" Might as well just take me out behind the woodshed and shoot me.
     
  9. jbarnhart

    jbarnhart New Member

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    <div class='quotetop'>QUOTE(darelldd @ Apr 14 2006, 10:21 AM) [snapback]239760[/snapback]</div>
    Uh... Have you seen your avatar?? I think somebody DID!
    :D
     
  10. donee

    donee New Member

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    <div class='quotetop'>QUOTE(RonH @ Apr 14 2006, 11:29 AM) [snapback]239697[/snapback]</div>
    Hi RonH,

    I am not an expert, but I never have thought of 6061 as "Aircraft Alloy". Looking at the web, it seems 6061 has some application in aeronatics, but the main Aircraft alloys are the 2024's and the 7075's. There may be newer alloys too (Al-Li alloys?). Some of the aircraft alloys (7075?) are more also notch sensative to fatigue. That is, a stone nick on the front of a plate made with one of these alloys might propagate over time and lead to premature failure. 6061 is like the bread and butter medium cost strutural alloy that gets used everywhere in non-aeronautic applications as best I know. Its quite strong, but not in the 7075 league. 7075 is about 1.8 times as strong as 6061 and almost as strong as untempered mild steel. 6063-T5 (commonly called architectural aluminum) is what is commonly available in hardware stores and is is about half as strong as 6061-T6, or about 1/4 as strong as 7075.

    There might be hard-anodizing issues with the 2024's and 7075's.
     
  11. RonH

    RonH Member

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    <div class='quotetop'>QUOTE(donee @ Apr 14 2006, 08:58 PM) [snapback]239966[/snapback]</div>
    I'm not an expert either, but let's not let that slow us down. I was referring to fatigue fractures which I think are common more or less to all Al alloys; after so many stress cycles the stuff just comes apart. Stress risers such as nicks or burrs can accelerate fracture formation in any metal which I think of as locally exceeding yield strength. Just some things I would think of flying down hills at 50 mph on my bikes to take my mind off the fear! Good night.
     
  12. Danny

    Danny Admin/Founder
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  13. Alnilam

    Alnilam The One in the Middle

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    Is there any stiffening factor added by installing a tow hitch to the car? I thought I read somewhere that this was experienced by someone. (The tow hitch adds a bracing structure across the back of the car.)
     
  14. DaveinOlyWA

    DaveinOlyWA 3rd Time was Solariffic!!

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    some but the offset change in balance would overrule that i would this. if the bracing extended to the middle of the car, it might be more effective.
     
  15. jrfaris

    jrfaris Member

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    <div class='quotetop'>QUOTE(BT Tech @ Apr 12 2006, 09:20 PM) [snapback]238946[/snapback]</div>
    This brings up a question I've had since installing the BT plate. I had the feeling that these reliefs were too shallow and that the plate actually rested on the thicker portion of the frame rather than bearing tightly against the frame at the front bolt location. I am wondering what you mean by "adequate clearance"? I believe that, at the specified torque, there is no clearance at the reliefs/thicker frame section but there is clearance near the forward bolt location. I haven't tried to verify this but it appears that I could slip a feeler gauge between the plate and the frame in front of the forward bolts. I would just like to know whether this is a condition I should try to correct. I have to say that I haven't noticed as much change in handling as others have observed.
     
  16. BT Tech

    BT Tech New Member

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    Due to the placement of a tow hitch on a vehicle there is little to no added benifit regarding the stiffening of a chassis.


    <div class='quotetop'>QUOTE(Alnilam @ Jul 14 2006, 02:49 AM) [snapback]286120[/snapback]</div>

    I am not sure what you mean by saying that the reliefs were too shallow?? If you are referring to the notches that we machined into the plate this was put there soley to provide adequate clearance of the frame rails. In other words if the "reliefs" were not machined into our plate then the plate would not fit withouth the front of it making contact with the frame rails.

    Our plate is physically larger than the stock one it replaces therefore these reliefs were necessary to allow for a perfect fit.




    <div class='quotetop'>QUOTE(jrfaris @ Jul 14 2006, 11:25 AM) [snapback]286212[/snapback]</div>
     
  17. jrfaris

    jrfaris Member

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    <div class='quotetop'>QUOTE(BT Tech @ Jul 14 2006, 07:21 PM) [snapback]286535[/snapback]</div>
    As I stated, on my installation, the reliefs (notches) are not deep enough to provide "clearance" for the thicker portions of the frame rail. The bottom of the notch rests on the thicker portion of the frame rail and prevents the major portion of the BT plate from fully contacting the frame rail so there appears to be a gap between the plate and the frame rail at the front bolt locations. Here is a picture to help clarify.
    [attachmentid=4155]
     
  18. Alnilam

    Alnilam The One in the Middle

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    The pictures that show how to install the BT stiffening plate don't resemble my 2006. I don't see any factory installed plate near the muffler as the pix shows. Is it a different procedure on the 2006?
     
  19. jrfaris

    jrfaris Member

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    <div class='quotetop'>QUOTE(Alnilam @ Jul 16 2006, 10:01 PM) [snapback]287421[/snapback]</div>
    Check pix in post #107 of this thread:Installed on 2006 Looks like it should be the same. It's located in the general area below the rear passenger foot wells.
     
  20. Alnilam

    Alnilam The One in the Middle

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    <div class='quotetop'>QUOTE(jrfaris @ Jul 17 2006, 09:51 AM) [snapback]287580[/snapback]</div>
    Thanks, jrfaris. I wonder if anybody wants to do a little missionary work and supply a picture of before and after for the 2006. I looked hard and didn't see anything that resembles the stock plate.