I have one of the first IRS Pinion Braces installed on my car.
First I must commend Rich for all the time he spend developing the brace. The Fit was SUPURB!!!!!! Every contour matched my car PERFECTLY!!!!!!
Some installation notes. If you want to install the brace with the exhaust & gas tank still on the car (like I did), you can Not use a socket on the lower control arm nut. The lower control arm nut is 1 5/8". I bought a set of huge BOX END wrenches from Harbor Freight ($40). You will want to soak nut, bolt, & bushings several times with PB Blaster, & let it sit for at least a day. You'll be Thankful you did!!!!!! I had the car on ramps for the install. To break the nut loose (160 - 240 ft/lbs!!!!) I braced my back against the opposite wheel & ramp, and pushed on the box end wrench with my feet.
Once the huge nut is off, tap the bolt back, until only about 1/16" of it is sticking out from the frame. Don't tap it all the way through the bracket, because the diff. will sag from lack of support. It's a real PITA getting everything to line back up. BTDT!!!!! I used a box end wrench on the head of the lower control arm bolt, to ensure that the bolt didn't turn with the nut. It wasn't necessary though, due to the liberal dousing with BP Blaster for 2 days.
I HIGHLY RECOMMEND that you install the Poly diff. bushings along with the brace. If you Need the brace, then you need poly bushings too!!!!!! I also have (& HIGHLY RECOMMEND) the poly rear diff. mount that Wynn (tbird88) makes & sells. I do not have Any increase in noise or vibration with either of the poly mounts or the IRS brace.
You can get an OPEN END wrench on the top of the front diff. mount bolt. You feed the wrench up between the gas tank & diff. Then hold the wrench with your other hand, up around the Back of the diff. My front diff. mount bolt did not move at all when I loosened up the bottom nut, but I had the wrench on to top nut, just in case it did.
The one thing I had to modify, was the heat sheild on the bottom of the gas tank, passenger side. Mine was pretty badly bent up, & I had to use some tin snips to cut a small portion of the it off. This in No way reflects on the IRS brace!!!!
Now about controlling HWH. The IRS Pinion Brace made a HUGE difference in reducing HWH!!!!!!! Enough of a difference, to make the price of it, insignificant compared to the improvement it deliveres. I haven't tested it at the Martin Dragway yet, but on the street, it eliminated about 80% of my HWH. Once again, I also have the poly front diff. bushings & Poly rear mount. If you still have OEM rubber mounts, your HWH may not be reduced as much as mine was.
My HWH was so bad ( modded '89 5-spd) that on the strip, in the past I've always had to pedal the car in 1st. gear to control the hop, & hopped it pretty bad on the 1 - 2 shift. I even hopped the 2 - 3 shift most times.
I see that you're from Midland. I'm from Buchanan (SW MI.), but spend quite a bit of time at my parents place in Martin. They live close enough to the drag strip, that we can hear the loud speakers clearly. Midland isn't that far from Martin, We should get together sometime! I'd like to see an SC mini-meet in our area this summer.