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Floor Reinforcement Brace

Discussion in 'Gen 2 Prius Accessories & Modifications' started by sparkymarvin, Aug 6, 2007.

  1. sparkymarvin

    sparkymarvin Member

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    Hello Everyone,

    I would like to install the Tom’s Floor Reinforcement Brace or the equivalent part from the new Prius Touring Edition.

    My first choice is the Toyota part.

    My questions are:

    1.) Will the touring edition part fit on my car? Are the existing bolt holes the same as the standard Prius? Has anyone else tried this installation? Does anyone know the part number?

    2.) Will the Tom’s part fit? It says the following on their website:
    “As for the genuine muffler and the vehicle except a TOM'S barrel wearing car, there might be interference.â€
    Does this mean that the part will not fit unless the Tom’s exhaust is also installed?

    3.) Is there a difference between the stock plate on my 2004 Prius and the stock plate on a 2006 or 2007 Prius? I have taken a look and have not noticed any physical differences, but perhaps there is a materials difference.

    Finally, if anyone has pictures of the Tom’s plate installed, I’m sure people here would love to see them.

    Thank you.

    ~Andrew
     
  2. apriusfan

    apriusfan New Member

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    <div class='quotetop'>QUOTE(sparkymarvin @ Aug 6 2007, 01:22 PM) [snapback]491469[/snapback]</div>
    It should fit given all of the BT Tech plates that have been installed on non-Touring edition cars. Someone else will have to provide the part number for the OEM plate. However, if you really want to go with the OEM plate, a quick post in the BT plate thread should get you any number of responses from people who like the BT plate and are willing to send their OEM plate to you (probably for just the cost of shipping).

    <div class='quotetop'>QUOTE(sparkymarvin @ Aug 6 2007, 01:22 PM) [snapback]491469[/snapback]</div>
    Based on another thread about the floor stiffening plate, there are problems with clearance between the TOM'S part and the OEM catalytic converter. There may be problems with clearance of the muffler on the OEM cat-back exhaust as well.

    <div class='quotetop'>QUOTE(sparkymarvin @ Aug 6 2007, 01:22 PM) [snapback]491469[/snapback]</div>
    Doubtful regarding materials difference, unless the thickness is less on the different plates.

    Out of curiosity, what are you trying to achieve with the floor stiffening plate? If handling improvement is your objective, the front and rear suspension braces are a better return for $ spent.
     
  3. sparkymarvin

    sparkymarvin Member

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    Thanks for the reply apriusfan.

    I was going to replace the stock plate somewhat for handling, but also just because I am getting antsy regarding how little maintenance the Prius requires. I guess I'm just looking for something to play with.

    I am going to try asking around here if there is someone who has a touring edition plate that they would like to sell me.

    What are the front and rear suspension braces you are refering to? I am familiar with the front brace that is mounted over the struts made by Tom's. I also think they have a swaybar for the front, but I don't know about a rear one. Are you refering to TRD parts?

    Thanks again.

    ~Andrew
     
  4. apriusfan

    apriusfan New Member

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    <div class='quotetop'>QUOTE(sparkymarvin @ Aug 14 2007, 12:48 PM) [snapback]495522[/snapback]</div>
    Check out http://www.sigmaautomotive.com they sell the complete set of TOM'S suspension products. I was specifically referring to the TOM'S Upper and Lower Front Suspension Braces and the Rear Suspension Brace. The TOM'S Upper Front Suspension Brace is the strut re-enforcement bar you are mentioning in your post; the Lower Front Suspension Brace is a complementary bar (not a sway bar) that locks the lower part of the front suspension from movement during cornering. The TOM'S Rear Suspension Brace performs a similar function (reducing flex of the rear suspension). If you want something to play with, the TOM'S bits will get you much better handling than the OEM chassis stiffener that is fitted to the Touring edition. I know, since I have a Touring edition.

    The way I would characterize the difference between the TOM'S suspension braces that I just mentioned and the TRD Sportivo springs and shocks is that the Sportivo springs and shocks is kind of like the Touring suspension on steroids. With the TRD Sportivo springs and shocks, you also end up with a car that has a lowered ride height by about 1 inch. I personally did not want a lowered ride height and did not see where swapping out springs and shocks (TRD Sportivo) would solve the marshmallow handling experience. The TOM'S suspension braces have definitely cured the marshmallow handling experience.

    It is just my opinion, but if you are wanting to tinker with your car, you can do so much better than fitting the OEM chassis plate. Some ideas for your consideration (based on my experience):

    1. Lightweight (forged) wheels and wider (205mm) tires;
    2. TOM'S Front (upper and lower) suspension braces;
    3. TOM'S Rear suspension brace; and
    4. Hawk Ceramic compound brake pads.

    My next modification focus will be to fit park assist (the beeping kind) front and rear.
     
  5. Pinto Girl

    Pinto Girl New Member

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    I respectfully disagree...the Sportivo bits totally firmed up the car.

    After all, the "marshmallow handling experience" is caused primarily by too soft springs/struts and shocks with insufficient damping. Not by a floppy chassis.

    Here's my list of things added to my car:

    (1) TRD suspension
    (2) BT brace

    Cost: $1100.

    That's it. She no longer pushes (understeers) nearly as badly as stock, and the limits are much higher and more predictable. And, unlike adding bigger tires, there's no MPG hit (and I can fly unnoticed under the radar).

    I think it's against the spirit of the car to modify it for performance in ways which compromise MPG...a better suspension lets you go faster, keep the stock rubber (till it's worn out) and rims, and not lose any fuel economy, either.

    As far as changing brake pads, the Prius uses the friction brakes so little to begin with (even when flogged mercilessly) that, in my opinion, better pads are pretty much a waste of money.

    Nothing wakes up a car like new springs, shocks and struts. And the lower ride height isn't really *that* bad, as long as you've driven a lowered car before and know how to approach and depart steep driveways and such.

    The "touring edition" plate is exactly the same as the stock chassis reinforcement plate, BTW. Except for the slightly firmer suspension and the wheels, it's exactly the same car.
     
  6. Presto

    Presto Has his homepage set to PC

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    BT brace is a good way to start out. It's relatively inexpensive, and it's probably the easiest piece to install. I highly recommend the Sportivo upgrade. The initial handling/ride difference seems subtle over the stock shocks and springs.... and then you take that first hard turn. Ain't no one taking away my TRDs! You might decide to stop there, or you just may go all out and get the other suspension pieces. I just need to install the floor brace and then I'm done, but even without it, my Prius handles oh so sweetly.
     
  7. sparkymarvin

    sparkymarvin Member

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    Well, I can understand both arguments.

    I strongly agree with you Pinto Girl, when you said, "the 'marshmallow handling experience' is caused primarily by too soft springs/struts and shocks with insufficient damping. Not by a floppy chassis.

    As much as I would love to have the TRD springs and struts, I live in an area where the Sportivo package would just cause too much trouble for me. I need that extra inch around here.

    I also plan on keeping the stock wheels in the name of fuel efficiency.

    Thank you for the link apriusfan. I am going to take a good look.

    ~Andrew
     
  8. apriusfan

    apriusfan New Member

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    <div class='quotetop'>QUOTE(Pinto Girl @ Aug 14 2007, 01:39 PM) [snapback]495572[/snapback]</div>
    With a non-Touring edition, you will see a dramatic improvement in handling by adding the TRD Sportivo. But don't underrate the TOM'S bits. Ask Presto if they want to part with the TOM'S parts and go with just the TRD Sportivo.

    <div class='quotetop'>QUOTE(Pinto Girl @ Aug 14 2007, 01:39 PM) [snapback]495572[/snapback]</div>
    The 205mm tires don't stick out like sore thumbs and combined with lighter than stock wheels, there was no MPG hit by going with the lighter wheel & wider tire combination. Actually, I was able to improve on the mileage by ~1 mpg, so no downside efficiency-wise. In addition, wider tires (and better tire compounds) contribute to an improved handling experience (with no MPG penalty).

    <div class='quotetop'>QUOTE(Pinto Girl @ Aug 14 2007, 01:39 PM) [snapback]495572[/snapback]</div>
    I think we will have to agree to disagree on this item. With the combination of better tires and ceramic pads, my car stops approximately 10 feet shorter (60-0) than the 2007 Prius loaner that the dealer provided. 10 feet can be the difference between getting in an accident and avoiding one. Also, no dusting of the wheels with the ceramic pads.

    <div class='quotetop'>QUOTE(Pinto Girl @ Aug 14 2007, 01:39 PM) [snapback]495572[/snapback]</div>
    "Adjusting" driving style to accommodate a lowered car is a personal decision. Personally I really don't want to have to approach every driveway from an angle and have to inch my way forward/reverse to avoid scraping the underside. But others may have no issues; again it is a personal decision.
     
  9. Pinto Girl

    Pinto Girl New Member

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    <div class='quotetop'>QUOTE(apriusfan @ Aug 14 2007, 04:59 PM) [snapback]495638[/snapback]</div>
    My recollection is, add the TRD bits first, then go for that little bit extra with the chassis bracing. Other posters have discovered this, too, and there are threads which will verify that.

    <div class='quotetop'>QUOTE(apriusfan @ Aug 14 2007, 04:59 PM) [snapback]495638[/snapback]</div>
    I don't agree. Wider tires and stickier compounds add rolling resistance...that's why the Insight has itty bitty tires, as does the Prius. Bigger wheels help handling 'cause they're wider (generation of higher g-forces) and the footprint is longer (makes the car more stable).

    Tell me, again, how you *increased* mileage incrementally with bigger tires and wheels? How much lighter than stock is one of your tire/wheels? Which combo are you running? I can probably find the total weight myself.

    They must be very light indeed!

    <div class='quotetop'>QUOTE(apriusfan @ Aug 14 2007, 04:59 PM) [snapback]495638[/snapback]</div>
    How many tests did you do? Under different conditions? No offense, but I'm usually pretty skeptical of "it worked for me" testimonials that aren't backed by reliable statistics. Do you have those?

    <div class='quotetop'>QUOTE(apriusfan @ Aug 14 2007, 04:59 PM) [snapback]495638[/snapback]</div>
    Agreed; but it's really not nearly as bad as you're making it out to be. No inching forward/reverse (first time I've heard of this, actually)...just things like not pulling all the way into a parking space until the tire hits the bumper (which good drivers avoid doing anyway). Besides...I'm only a girl, and I'm doing just fine!
    [laughing]

    Isn't that terribly sexist of me?!?
    :)

    PS, I'm telling you, you're not going to feel much of a difference, even if you spend as much as you can and buy every TOM's brace there is.

    I think your advice is not well-founded and I'm concerned that you're leading sparkymarvin astray.

    I'm only mentioning it so he doesn't go through all the work, only to be disappointed.
     
  10. Presto

    Presto Has his homepage set to PC

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    The stiffness of the TRDs tends to even out 'bottoming out' issues with bumps and such. So even though it is a bit lower with TRD, the stiffness prevents the vehicle from dropping too far. In fact, here's what I said in this thread about speed bumps after I got the TRDs

     
  11. apriusfan

    apriusfan New Member

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    <div class='quotetop'>QUOTE(Pinto Girl @ Aug 15 2007, 02:59 PM) [snapback]496427[/snapback]</div>
    Unless the TRD Sportivo is not an option. Lowering ride height by ~1 inch may not be an issue for you. But for me (and apparently sparkymarvin as well) it is an issue. So when TRD Sportivo is off the table (so to speak), the TOM'S bits would appear to be the next option. Frankly, for me, the combination of Touring suspension (slightly firmer springs and shocks/struts) plus the TOM'S pieces is an ideal solution (and I haven't had to sacrifice ride height to achieve it).

    <div class='quotetop'>QUOTE(Pinto Girl @ Aug 15 2007, 02:59 PM) [snapback]496427[/snapback]</div>
    Well, maybe we have another area where we will have to agree to disagree. I did not put on "bigger" wheels (actually, smaller wheels). Wider tires by 10mm, but not bigger (as in larger diameter).

    <div class='quotetop'>QUOTE(Pinto Girl @ Aug 15 2007, 02:59 PM) [snapback]496427[/snapback]</div>
    The wheels are the 15x6.5 Motegi Tracklite forged wheels with a wheel weight of 10 lbs. The Michelin tires may be slightly heavier than stock tires, but when combined with the lighter Motegi wheels, the Motegi/Michelin combination is slightly lighter (I own the Touring edition, so when comparing total weight, you need to go with the Touring edition spec).

    <div class='quotetop'>QUOTE(Pinto Girl @ Aug 15 2007, 02:59 PM) [snapback]496427[/snapback]</div>
    No offense taken, but out of curiosity, based on your expressed skepticism of "it worked for me" testimonials, how did you overcome your skepticism and decide to purchase the BT plate? I certainly haven't seen any statistical data that purport to show the handling advantage of the BT plate. Indeed, a very significant number of pages in the BT Plate thread consist of flame exchanges over the absence of statistical proof of claims made on behalf of the BT plate. But I digress. My testing of the stopping distance improvement came with a G-Tech meter ( http://www.gtechpro.com ) and making 2 60-0 runs (once in one direction, then repeat in the other direction to cancel out any wind effect). The first run was completely cold and the second run was done warmed from the first run, so there is some bias. But the objective was to check order of magnitude as opposed to a statistically valid test that was significant at the 98th percentile. I did the same testing on the dealer's completely stock (non Touring edition) loaner. There was a difference of 11 feet and 12 feet, which I rounded down to 10 feet. Are you challenging my claim of no dusting for the ceramic pads as well? (It is not my claim; every brake pad manufacturer that sells ceramic pads claims reduced dusting versus stock pads....)

    <div class='quotetop'>QUOTE(Pinto Girl @ Aug 15 2007, 02:59 PM) [snapback]496427[/snapback]</div>
    I am not referring to parking issues with a lowered suspension. My issues are more in regard to high-centering or scraping the underside of the car on entering or exiting the roadway where there is an angled driveway. I am not unfamiliar with the scraping experience. My MINI with stock springs will scrape the front air dam at the drop of a hat on just about any driveway that is even slightly angled up from the roadway. I really do not want to experience high-centering; that would tend to accelerate corrosion of the chassis.

    <div class='quotetop'>QUOTE(Pinto Girl @ Aug 15 2007, 02:59 PM) [snapback]496427[/snapback]</div>
    That sounds like a personal opinion. Arguably not unlike the decision process on the BT plate. Some people find the BT plate improves handling; others do not. I wonder if Presto believes the TOM'S bits are marginal in their improvement?
     
  12. Presto

    Presto Has his homepage set to PC

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    I installed the BT plate first. It gave a noticeable increase in handling. The TOM's pieces went on after the Sportivo installation. I did incremental upgrades with the Tom's pieces. With each piece, the difference was significantly noticeable.

    I believe that the difference should be noticeable with the stock suspension as well. The chassis is comparatively flimsy without braces. By adding bracing, it allows the suspension to do more of the work of absorbing bumps and shocks instead of the chassis flexing, and causing body roll. Whether it be the stock or the touring, the difference will be there... just like there was a difference when I added the BT plate.
     
  13. apriusfan

    apriusfan New Member

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    <div class='quotetop'>QUOTE(Presto @ Aug 15 2007, 06:12 PM) [snapback]496576[/snapback]</div>
    I personally completely agree with your assessment. I am not knocking the BT Plate, I just think that more gain can be achieved with the TOM'S Rear Suspension Brace in comparison to the BT Plate. For that matter, I am not knocking the TRD Sportivo suspension; it is just that for me, the TRD Sportivo is not an option due my desire to not lower the ride height of the car.
     
  14. Presto

    Presto Has his homepage set to PC

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    TOM's rear brace is definitely better than the BT Plate, but at 1/3rd the cost, the BT plate should more than satisfy the majority of folks.
     
  15. apriusfan

    apriusfan New Member

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    <div class='quotetop'>QUOTE(Presto @ Aug 15 2007, 06:43 PM) [snapback]496596[/snapback]</div>
    No disagreement there either. But I would be perpetually wondering what I had given up by not getting the TOM'S Rear Suspension Brace.... Especially with your post after installing the TOM'S bit. It would have been like walking around with a tiny pebble in my shoe....
     
  16. freesolar

    freesolar New Member

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    <div class='quotetop'>QUOTE(apriusfan @ Aug 15 2007, 08:50 PM) [snapback]496599[/snapback]</div>
    Hey, if you want to vastly improve the ride and handling, go for it! I have had the TRD for several months now and can honestly say that I have noticed absolutely no difference with the 1" lowered ride "issue" (actually it is 3/4" in front and 1/2" in rear). I cannot believe anyone can tell the difference- it's not visually noticeable either- WOW what alot of talk and concern- creating a problem that does not exist. I am a aggressive driver and have never "bottomed out" anywhere? What problem???
     
  17. sparkymarvin

    sparkymarvin Member

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    Hi everyone. It's me again.

    I don't think I am going to perform any changes to the suspension of my car. Maybe if I save a little money I'll go with the BT plate just for fun, but for now I am going to sit tight. I appreciate all of your concern though.

    Thanks for your thoughts.

    ~Andrew

    PS I was hoping this thread wouldn't turn into some kind of debate.
    :unsure:
     
  18. apriusfan

    apriusfan New Member

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    <div class='quotetop'>QUOTE(sparkymarvin @ Aug 15 2007, 08:51 PM) [snapback]496679[/snapback]</div>
    Well, regardless of whether the thread turned into a debate, hopefully it was informative for you. There will inevitably be different perspectives on any given modification.

    BTW, you might check with Presto on the availability of a slightly used BT plate that was replaced by the TOM'S Rear Suspension Brace.