GrimmSpeed Strut Tower Brace - Review

[Gopherboy6956]

I just want to share my experience with the Grimmspeed Strut Tower bar. This starts out as a bit of a story...


For quite a while now, I've been a critic when it came to strut tower bars. They always seemed more of a engine bay dress up part than an actual structural part to me. I even did quite a bit of research when was planning my BRZ suspension mods, and one of them was whether or not I should get a tower bar. Well, in the course of my research, I read an article in Car and Driver on a guy who runs a K&C Machine for lots of motorsports teams, and he was quoted as saying something along the lines of "...he has never seen an aftermarket strut bar provide a measurable handling difference."

After reading that, I was convinced that this part was unnecessary for my car unless I was just going for looks (The finish on the bar was, after all, very nice)

So then, one day a few months ago, I was cruising facebook, when I saw GrimmSpeed talking about their new strut bar they were putting into production. I took a look, and armed with this 'new information' on strut tower bar testing, I stated my position.

Of course, that prompted GrimmSpeed to reply and state their position, along with a challenge - If I didn't think the bar would provide any benefit, they would like me try it out for myself. So, I thought - "what do i have to lose?"

As it ended up, we had a local HPDE track weekend coming up, so we worked it out that I could test the bar there. So they shipped one out to me. Here are a few photos from when I opened it:





It was packaged pretty well, with everything necessary for installation.

I won't detail the entire install process, mostly because it's so easy there almost is no process. Remove 4 nuts, install bar, replace 4 nuts kind of deal.

Here it is installed:







The next few days I drove it around town, but didn't really push it too much - just normal DD stuff, so I really didn't notice any difference, but I figured I'd try to reserve judgement until I was at the track.

So this past weekend I had the opportunity to put in some track time at Brainerd International Raceway in Brainerd MN. I had several 20 minute sessions, so it was a perfect time to test with and without the bar.

I tested first without it, since my suspension had been upgraded since my last track day, and I wanted to isolate the impact, if any, of the new bar and not confuse it with new suspension. Once I put the bar on, I felt an immediate difference when cornering. The front end was just planted - hardly any play in the tight corners and switch back curves. Its hard to describe, but I was sold. As the weekend went on, I was able to run two days of Autox as well, and again, felt a clear improvement.

I think one of the easier situations to describe was loading the suspension when I weight shifted the car in the middle of a sweeping turn (Turn 2, if you know the track)

I let off the gas to initiate my turn, and once I had my line, went right back on the throttle 100%. When the bar was not on the car, I would get a bit of hesitation from the front end when I wanted to hold the line. Less confidence inspiring, I'd say. With the bar it was very easy to hold my line as well as get good feedback from my front tires. Everything seemed to flow just that much better.

One thing I did notice a bit of, which I expected, is an increased amount of under-steer POTENTIAL. When the car was weight shifted properly into a turn, everything went fine, but If was off a bit, the car would push more than normal. The amount and intensity definitely would be different on each car depending on specific mods, but on my setup (Tarmac 0 Coils, 245/40 Dunlop ZII's, -1.5 Front Camber, -2.5 Rear Camber) that was the result. I'm sure I could eliminate it with a stiffer rear sway.

Anyways - I am very pleased with the bar - and I ate my words. There is a noticeable improvement provided. I definitely recommend this for anyone who wants a bit more stability out of their car - for track use or otherwise.

And, just because - here are a few track pics!

[the.big.kahoona]

Good post OP

[StormTrooper]

Why is your rear camber higher than your front? Seems contrary to everything I've read about alignments on this car.

Nice write up..

[GrimmSpeed]

Thanks for being willing to give the brace a fair chance and thanks for the write-up. Glad the brace is treating you well!

Matt Beenen
Engineering

[Gopherboy6956]

Just finished a weekend AutoX event, where our Sunday track was FANTASTIC. One thing I learned about the car now, however is this: I under-steer quite a bit with the tower bar on in an AutoX situation. On the larger road course, it kept the back wheels in line and was very confident. However, in AutoX, i need more rotation of the rear to get around some tight corners. I just pushed so much.

So, if you get ANY tower brace, you might want to look into a stiffer rear sway if you AutoX. How big? I'm not sure yet - but probably only mildly bigger - something like the WRX stock ones I hear are bigger and bolt right on. I welcome any suggestions.

[GrimmSpeed]

Sounds about right, depending on your setup. Obviously, others may experience this to a lesser, or potentially greater, degree. As with most things, your suspension system is about finding a balance. If you've got everything carefully dialed in and add a strut tower brace to the front end, you'll want to balance with adjustments in the rear.

Either way, thanks again for the awesome, detailed, honest feedback! Like I mentioned, results may vary based on how you've got the car setup (and what you prefer as a driver), but at the very least, this should quiet the "strut tower bars do nothing" crowd a bit.

Carry on!

Matt Beenen
Engineering

[sklimo]

I am installing mine in 10 minutes!!! Great write up!!

[pszuvela]

Nice write-up. I ordered mine today and look forward to testing it out. I've had great experiences with GrimmSpeed products on my 2002 WRX and look forward to my first GS product for my BRZ!

[mfbmike]

Thanks for the review OP. I'm also on Tarmac 0's and have a GS bar and master cylinder brace on the way that I found in the classifieds here.

[Frostyman]

Was actually thinking of taking mine off, since I'm stock all around, and I did notice a fair degree of understeer after install too. Probably stick it back on later.

[Gopherboy6956]

Originally Posted by Frostyman

Was actually thinking of taking mine off, since I'm stock all around, and I did notice a fair degree of understeer after install too. Probably stick it back on later.

Yea this can add understeer no doubt. However, I think it can be offset by an alignment change too.

If not, then a stiffer rear sway.

[OrbitalEllipses]

Originally Posted by Gopherboy6956

If not, then a stiffer rear sway.

More rear spring is also an option.

[fatoni]

Originally Posted by Gopherboy6956

Yea this can add understeer no doubt. However, I think it can be offset by an alignment change too.

If not, then a stiffer rear sway.

since you have no doubt, i would love to hear why. i have no idea how a strut tower bar would add understeer

[PoorMansRacing]

Originally Posted by Gopherboy6956

I under-steer quite a bit with the tower bar on in an AutoX situation.

Is everything else about your car's suspension stock?