Q's on Tom's parts and where to buy

I've been interested in improving the handling of my '07 Prius Touring, and finally am looking into the Tom's front upper performance rod, front suspension member brace, and rear suspension member brace. I'd include the floor strengthening brace, but I hear that the Tom's part interferes with the stock exhaust.

I'd be interested to hear from anyone who has some or all of these Tom's parts installed. Are they worth the effort and cost? Where to buy them? ...I was all set to order the parts from Carson Toyota, but got blown off the two times I called today (first put on hold for ten minutes and counting, next sent to voicemail). Anyone else supply these parts at a reasonable price?

Thanks much!

 

Hey thanks for all the comments. If anyone would notice the change in handling, then that person would be me. I did similar mods to my Integra years ago (now sold) and loved the transformation. Did anybody happen to drive around with the front/rear braces before putting on the floor strengthening brace? Curious am I to know what I may be missing if I pass on it. Then again, tweaking the exhaust route doesn't sound like a big deal, so I'll probably add the floor brace also if it makes a difference.

SaeGai06, thanks for the additional source. Sigmaauto's prices are a few bucks more, but they'll have my business if they can pick up the phone and deliver like normal people!

 

...Ha, what a coincidence. My other car is a P-car too (987S), and is perhaps the best handling mid-engined car in the world! Still, it can't haul four people, pick up the groceries, carry two bikes, squeeze into tight parking spots, *and* get 45 miles to the gallon. The Prius is in many ways a performance car and the best at what it is designed to do. If only it can carve curves with a bit more zest, then I'll be totally happy.

 

Update on the chassis brace modifications:

Several months have passed, and I indeed have purchased all three chassis kits. I eventually ordered my parts from Carson Toyota, since Sigma Auto's website didn't seem to offer a contact number. Carson Toyota turned out to offer a decent purchase experience. While not very easily reached by phone initially, the internet specialist was more readily accessible by email. The dealership had the upper front "performance rod" in stock, while the rest was backordered and took about six weeks.

Since the front upper strut brace was already in stock, I received and installed it first. For the last two months, I've noticed quite a difference in handling with just this single modification. The change is similar to what happened when I added this part on my Integra years ago; the car understeered less, felt less "squirrel-ly" when changing lanes on the freeway, and maintained better traction when braking. All this was a welcome addition, and no surprise when understanding that the part is meant to keep the strut towers more closely perpendicular to the road, and maximally maintain the front tires' contact patch. I also add that the car almost felt "wider," but maybe that impression was due to the fact that the factory-spec car was so very unstable at speeds anywhere above 70mph or through heavy crosswinds.

I think that -for the minimalists or more frugal Prius owners, who are interested in augmenting handling for the purpose of safety and a little bit of fun -just adding a front upper strut brace would be satisfying enough.

Anyway, the remaining parts have been sitting at my place for the last month. Just this week I got around to getting them installed. Probably because my Prius is a U.S. version, and the Toms parts are designed for a Japanese Prius, installing the the trapezoidal rear lower brace to clear the gas tank required adding enough washers to create a 3/4 - 1 inch spacer for each of the rear four bolt sites (there are eight total on that piece). As for performance, I'll post my thoughts as I spend more time with the car. My immediate assessment is that the car rattles less over bad roads, though the new braces do add/return a little bit of understeer.

Hmm. Well compared to the P-car, I'll say that I haven't lost any interest in driving it for fun. The Prius and the Porsche are two different animals. On an open curvy road, a briskly-moving 987 "pivots" around the middle of the car; the Prius seems to require a greater steering angle, feels "longer," and leans/rolls more. That said, the Prius beats the P-car -hands down -during bumper-to-bumper rush hour traffic.

 

I do believe the braces are money well spent. They also make me want to try lower-profile and slightly wider wheels to balance out the handling package. Or, maybe stickier tires will do. First I need to get used to the new setup. Body rigidity is noticeably improved, but at about a 35 lb. weight cost. With the front upper brace alone, the weight penalty is only about 8 lbs.

I'll post a picture of the front strut brace later. The front upper brace fits neatly under the windshield wiper mechanism tray, and in front of the firewall. The net appearance of the brace looks very clean. So clean, in fact, that I wonder why Toyota didn't add it as original equipment on the Touring.

Installation of the front upper strut brace is more involving than a similar mod on a typical compact car. Due to very efficient use of engine bay space, what should be a six-bolt procedure turns out to also involve temporary removal of the structures above the strut towers, i.e. window wipers, wiper motor cover, wiper motor, wiper motor tray, and fuse box. Then a little wrapped wire attached to the passenger-side strut tower needs to be relocated an inch lower. Although a little more involving than usual, installing the front upper strut brace is very manageable if you're mechanically-inclined and have 1 - 2 hours to spare.

 

Hey nice pics on the BT Tech strut tower brace. The Toms part looks almost identical, and installs exactly the same. I'll snap a pic of it on my car soon.

As for the lower parts, install is a snap but requires access to the underside. Since I don't have a lift in my back pocket, I had my dealer put them on. A potentially helpful pic may be of the stacked washers that sit between the lower brace and chassis fore of the rear wheels, so I'll take a pic there, also.