Suspension Tech: Bring It!

[BMR Tech]

Kelly, I have a 2013 Gt that is lowered 1.5 inches front and back. I am still on stock dampers and struts. I have the BMR adjustable panhard bar intstalled. I have 3.73 gears and I am on stock 19" tires and wheels. My question is I tried to measure pinion angle and I believe it came to zero. So I ordered BMR lowering brackets and BMR LCA with poly bushings. I am going to set the brackets in the middle hole to try to get LCA back to level. I am wondering...once I lower the LCA shouldn't it in theory lengthen the geometry of the rear suspention giving back my stock pinion angle.I'm thinking by about 1/8 to 1/4 in forward...am I correct...Thanks Lyle...I don't plan on taking car to track,just spirited driving !!

We do compensate for the arc, in our positions on the LCA Brackets.....BUT, that only "works" if the brackets are EXACTLY where they should be positioned. It is difficult to ensure each and every installation is exact....it is tough when dealing with increasing the length of the lever.

Your best choice would be to just install the components, and see where your at afterwards. Let me know.

maybe Mr. bmr can help me
uca in top hole. -2 pinion angle. lowers in middle hole. launch rpm 5000. 26x8.5 slicks. wicked hard initial hit and bogs! all the way down to about 2000rpm. then it has to pull itself back up. only a 1.80 60ft???

Too much hook!!!! Anytime you find this happening, you should thank me. It's simple from here on out. Your goal is to either launch higher, or promote some wheel speed. Either will improve your 60' drastically.

Try 5500....6000...6500....etc.

If you are scared of RPM, raise the LCA up a hole and raise the tire pressure 1-2 psi.

Let us know!

Odd behavior question. When flooring it in first / second, the rear end of the car has always gently swung out. Generally it would swing out to the left in first, then a little to the right when I caught second (Note this is with Advance Track enabled). I could always just "drive through it".

After adding BMR LCA relocation brackets (using top hole) and J&M tubular LCA's, the rear seems to break loose much more violently. There's a ton more lateral movement to the point of almost losing control. The rear really starts coming around. Any idea why the behavior has changed?

Other car details: 13' GT Track pack 6sp, 3.73's, Hotchkis springs, staggered wheels / tires. 255 P-Zeros front, 275 rear.

It sounds like you may simply be overpowering the P-Zeros.

Try to lower the tire pressure a bit, and see if it helps. Occasionally, this can happen, where the increased anti-squat can cause the tires to spin even more. A softer compound tire, or stickier pavement is usually the fix. Our upper control arm Mount, in the upper position, should help too.

 

[BMR Tech]

Hey Kelly.. I talked to you a few weeks back on the phone. I ended up going with Eibach sportlines springs, BMR relo, BMR adj lca, BMR adj panhard bar with new wheels and tires ( nitto nt05)
I now have a noticeable noise from the back of the car that can best be descibed as friction. It is there clutch in or out and is directly related to speed. The car has been checked for any interference with wheels and it's aligned perfect too. The tech that did my car said the new lca mounts transfer more noise and that is probably it. What do you think?

You are experiencing the result from increased rigidity from the rear suspension pieces.

The noise you are hearing, specifically, is likely a combination of increased road noise and drivetrain operating frequencies.

There is no reason to be alarmed, unless you are experiencing noises that sound like the car is falling apart, IE; massive and loud clanking / clunking.

It is 100% normal to experience what you are.

 

[hoodley]

haha! thank you very much Kelly! not scared of rpm, just a little worried about scattering the rearend!
I will deff try your advise tho, i aint that worried...

 

[IamRacerX]

You are experiencing the result from increased rigidity from the rear suspension pieces.

The noise you are hearing, specifically, is likely a combination of increased road noise and drivetrain operating frequencies.

There is no reason to be alarmed, unless you are experiencing noises that sound like the car is falling apart, IE; massive and loud clanking / clunking.

It is 100% normal to experience what you are.

Thank you!! I do feel better. The car handles amazing btw!!!

 

[11socal50]

i have a 2011 GT auto, currently has BMR relo brackets, LCAs, adjustable panhard bar and brace. I will be installing koni yellows, hotchkis springs and steeda UCA and mount.
my question is, which hole should i use on the mount? it's my dd and will be a weekend canyon carver.

 

[007snake]

Hi Kelly,
You can see my mods in my sig. My problem is that I am wanting to go to a dr and the smallest diameter is nitto, 28.58" This means I am going to have to raise my car, the tires I currently have on it are 27" and less in the front. If I go to the Nittos on the rear I will also do the 555's on the front requiring that to be raised. So, I have ordered Eibach height adj coilovers but am thinking now that it will make the ride much more stiff. I love the dspecs and might just have to go with new springs?? I might drag race once or twice a year and with my hp don't think the Verds are going to give me enough traction on the street. Thank you in advance for your thoughts.
mark

 

[Dragonpassion]

BMR tech. .. A little input on my set up before question.

13 gt. Rag top, premium with bimbo package. Slotted and drilled rotors. Mt82 trans. 3.31 rear gears.

Mods... Whipple 2.3 with a 2.875 pulley. 47 lb injectors. BAP. One step colder brisk plugs. 70 stat. Gt500 twin 68mm throttle body. JLT big air. Large liquid cooler with dual heat exchange fans. Dino tuned to 634 rwhp. 565 rwtrqu. 20 inch staggered rims with Toyo 315 30 20 r888 drag radials on rear. (they are MONSTERS and I do know, the 20s are not a good idea with my set up, but i love the look) BBK tuned shortys headers. Cat deleats. Off Road X pipe. Magna flow out the back. Whiteline trans bushing. Steel hi flow cluch line. MGW's newest 2014 revistion shifter. Shaftmaster aluminum drive shaft. Trans, oil and diff coolers. BMR safety loop. BMR relocation brackets (lca's are in the top hole) J&M EXTREEM LCA. J&M adjustable pan hard bar (rear end is Dead center) and other minor stuff. All that said, so you know about my car.

And now my problem... yep, I'm still braking traction in 1st and 2nd at hard launch and 1st and 2nd rolling WOT. 3rd holds. Pinion angle is just north of -05. Car is not lowered. What more would you recommend to get these tires planted better? I own a 05 Rag Top 4.0 Mustang so my 13 5.0 is my baby and is not a daily driver. It will go to the track for official 1/4 time this spring but other than that, the car is for street driving, street races, car Shows and weekends.

It is late. Please excuse misspelling as this is from my phone.

ANY Recomendations for the suspension to grip better? (Maybe Ajustable UCA and braket. Im being told i dont need one with my set up) What about Shocks? The car is AMAZING and does very well with these mods and set up... but will brake traction most hard launches or rolling launches.

Thank you for reading, your time and any helpful indight !

 

[BMR Tech]

Updated thread with Q&A on first page.

ALSO - added a pinion angle video too!

Dragonpassion, 007snake, 11socal50, Do you guys still need some assistance?

 

[BMR Tech]

BMR Suspension S197 Driveline Angle Video "Pinion Angle"

 

[nonliberal]

Good video Kelly!

 

[BMR Tech]

Bring it?

 

[techwerkz]

What advantages do adjustable LCA's have over the boxed, and tubed versions? Also a boxed vs tube breakdown? For ease of explanation lets say the car is lowered and using your LCA relocation brackets.

Also are all 3 of the springs rates now available that you mentioned earlier? If so what's the drop difference between the sets.

Thanks!

 

[Gpcalero]

What advantages do adjustable LCA's have over the boxed, and tubed versions? Also a boxed vs tube breakdown? For ease of explanation lets say the car is lowered and using your LCA relocation brackets.

Also are all 3 of the springs rates now available that you mentioned earlier? If so what's the drop difference between the sets.

Thanks!

Bump, I would also like to know this.

 

[Gpcalero]

Kelly, I was under my car yesterday fixing my vent tube issue, and I noticed this.

I removed the axle weights some time ago in Feb and was wondering if this was normal? This is the drivers side bracket.

The holes aren't aligned and it seems like the bracket warped?

 

[BMR Tech]

Not good!

Go, ASAP, and grab (2) 12mm x 1.75 bolts that are 25mm (1") length....install them and torque to 45ft/lbs.

Don't lose that aluminum spacer that I see between the brackets!

I'll answer the other question tomorrow. I am tired.

 

[BMR Tech]

What advantages do adjustable LCA's have over the boxed, and tubed versions? Also a boxed vs tube breakdown? For ease of explanation lets say the car is lowered and using your LCA relocation brackets.

Also are all 3 of the springs rates now available that you mentioned earlier? If so what's the drop difference between the sets.

Thanks!

Box VS Round Tube:

I don't really want to get into the super specifics here, but I will shed some light on why we like the box tube material.

Mass for Mass, Weight for weight, technically, the round tubing is stronger. That said, with the S197 LCA....the boxed tubing we use, is definitely stronger on paper than round tubing (or, most round tube offerings)

The primary reason that we use the box, is to ensure we can get a clean full "wrap" around the bushing end.

The weakest way to design a load bearing bushing end/pivot point, is to join the bushing end with a small tube. This is the reason our adjustable UCA have those massive adjusters, instead of welding a threaded rod to the bushing end.

Adjustable VS Non-Adjustable:

Most of my customers do just fine with non-adjustable LCA. Adjustment comes in handy when you want to "perfect" your rear suspension geometry, in terms of alignment. For example, if you install non-adjustable LCA, and have a thrust angle of say .10 to .25 (somewhat common)....it is within "spec", which is -.50 to .50.....but it is not perfect. You CAN dial it in to zero, but it takes some serious manipulation of the rear suspension. Much harder than just adjusting a LCA to hit the spec.

Often times, you can get your thrust angle zeroed out with the panhard bar adjustment, BUT....I'd rather the axle be centered within the rear chassis, THEN adjust thrust angle via LCA. Now, too much of anything is bad...so if you have to adjust one LCA more than 1/4" or so different than the other, then you will want to start looking into modifying or manipulating the mounting points of the LCA, etc.

The other benefit to adjustable LCA is the ability to alter wheel base. In handling applications, slightly short wheel bases can be beneficial for throwing the car around aggressively, longer wheel bases can be optimal when road coursing, with not much aggressive maneuvers. Lengthening the wheelbase increases stability, per say.

In drag racing, longer wheel base is always better.

Other adjustments can be beneifical, when speaking of wheel base. For example, if someone likes to run SERIOUS anti-squat....OR, serious squatting.....the wheels/tires actually come forward on launch, which will enable the tire to hit the fenders. I see this A LOT. The rear axle is on an arc. The more suspension travel, the more the wheels move forward.

The best LCA we offer, happen to be the adjustable. Simply because bearings work better for EVERYTHING (except NVH) than poly. So, in other words, the best performing LCA we offer is a fully adjustable set with bearing ends. Not necessarily the best because adjustable, but, the best; because racecar.

Lowered Car with LCA / LCA Relocation Brackets:

I have definitely touched on this earlier, but my recommendation for a lowered car is to get our UCA Mount that has an upper hole specifically engineered for a lowered S197 that uses LCA Brackets. Install the LCA Brackets into the Middle hole to start, then figure out which of the 3 positions works best. Most times, it is the middle.

In terms of adjustability for these LCA, on a lowered car and relocation brackets.....it isn't necessarily needed, but the more adjustability the better. I cannot promise each and every customer, out of tens of thousands, that their "specs" will be dead nuts OEM with these modifications, so adjustable LCA are definitely worth having. 9 times out of 10, I just recommend our good ole non-adjustable poly bushed LCA though.

Future BMR Spring options / availability:

They are not available yet. Springs are somewhat complicated, from start to finish in terms of releasing them to the public. You will definitely know when they are available.

The drops are all going to be in the 1.5" range. This is the height that we feel the S197 should be at, and is also the height we engineer our components around. Drag, looks, handling.....we prefer the 27.25" to 28" fender heights for all of it. Of course, results may vary based on tire heights, etc.

 

[nonliberal]

Making great progress with your help Kelly! THANKS!!

 

[BMR Tech]

*Added some stuff to the first page.

-Before and after wheel hop reduction videos with the BMR UCA and Mount.

-A Reply I made in another thread, at the bottom of the first post about what I personally recommend for the person looking for simple change, less nvh, kinda stuff.

Making great progress with your help Kelly! THANKS!!

Awesome to hear! Glad that's the case, I gotta earn a paycheck somehow.

 

[Mineral_01']

Vote to sticky this now! So much awesome information on page 1. It's nice being able to see everyone's questions all on one page instead of using "search" and browsing different pages.

 

[DIB2014]

Hi Kelly - great thread and a lot of very useful info. Appreciate all your time with this!

I have a sequence question for my 2014 GT, TP/Brembo that is NOT lowered at the moment (maybe in the future - driveway issues at present - wanted to upgrade all components in case lowering in the future - and enhance handling/eliminate wheel hop). Good chance FI is in the future as well.

I purchased a one piece drive shaft (DSS), BMR LCA (ACA004), LCA Relo Brackets (CAB005), UCA (UTCA032) and UCA Mount (UCM002), and Adj. Panhard Bar (PHR006).

Appreciate any guidance on the sequence to remove/install, and at what point is the axle on jacks OK to torque down bolts, and when it needs to be on the wheels before I torque the bolts/nuts down. I have race ramps which might make this a bit easier.

Also, hole location suggestions for the UCA and LCA for my set-up to be in the best starting position to eliminate wheel hop.

TIA!