BMR Tech2

iTrader: (5)

Lately we have been seeing and receiving a lot of questions regarding weight savings and the advantages of swapping to tubular front suspension components versus the stock pieces. Being as we had all the parts on hand to do a comparison, we decided to do just that.

Here are the players:
Stock LS1 K-member
Stock Lower Control arms
Stock Upper Control arms

BMR KM003 LS1 K-member
BMR KM013 LS1 Turbo K-member
BMR AA002 Lower control arms
BMR AA001 Upper control arms
BMR AA004 Adjustable Upper control arms

Plus a non-biased Fairbanks shipping scale



First, we zero'ed our scale. For all fairness we re-zero'ed the scale after EACH part was removed from the scale to prevent any variances and error accumulation. We wanted this to be as fair and accurate as possible.




First up, we put the Stock LS1 K-member up on the scale. The stock unit weighs in at a portly 57 lbs.


Next, we added the stock lower control arms. To take everything into account, we also added in a pack of hardware. This whole package came in at a whopping 85 lbs. That's a good bit of weight on the front of your car.


Then, we put the stock lower arms by themselves up to see what they come in at. We registered them at 25 lbs


Now, it was time to see what difference tubular components make

First up, our KM003 Standard LS1 k-member. It tipped the scales at a whole 26 lbs. That is a 31 lb weight difference!



So then we put our KM013 LS1 Turbo K-member on the scales. As expected, it was the same. 26 Lbs



So just to put that into perspective, you could bolt 2 of our K-members to your car and STILL be lighter than your stock unit



Now it was time to see what the difference in the lower arms. Our AA002 tubular arms with all hardware weighed in at 22 lbs. Slightly less than stock, but still lighter and more adjustability with less bulk.



Then, we put the KM003 and a set of our AA002 lower control arms up on the scale, with all corresponding hardware. This whole package came in at a total of 48 lbs. As compared to 85 lbs on the stock piece, that is a huge difference of 37 lbs!



So, to spite some recent rumors and misconceptions that "mild steel K-members don't save much weight", you will see a significant weight difference just from switching to tubular components. Not to mention the added clearance and strength.

This brought us to another point that is not discussed as much; Upper control arms. There is also a fairly common misconception out there that 4th gens do not have upper control arms. That is 100% incorrect. While they are not commonly replaced, they are there and are something to be considered by those seeking ultimate weight savings, strength, rigidity and even additional adjustability for alignment specifications.

So first we put a set of stock stamped upper arms on the scale. We did not have balljoints for these arms. So to be fair, we compared all upper arms without balljoints. The Stock units weigh in at 6 lbs.



Then we put a set of AA001 non-adjustable uppers on the scale. They came in at 5lbs, only 1lbs of weight difference, but every bit can count.



We also put a set of our AA004 adjustable upper arms up to see. As we expected, due to the extra hardware and rod ends and such, they came in at 7 lbs. 1 lb more than the stockers. However, they can provide much more camber and caster adjustment for those who are lowered more than usual, or are after hardcore handling performance.




Hopefully this will clear up some questions and rumors that are out there about the differences and benefits of tubular front components, and especially those made of mild-steel.

A little more info to add to this, for those trying to find all the weight savings they can from the front end. Here is a comparison of a stock power steering rack vs a manual pinto rack that we offer as a bolt in for these cars. There is a weight difference of 7lbs just in these parts. Plus another 10-11lbs from eliminating the pump, hoses, fluid etc that goes along with the power steering. So a total of close to another 20 lbs.




So with the addition of a tubular k-member, arms and a manual rack you are looking at saving over 50 lbs off the front of your car.

A little more info to add here, as far as weight savings on the front go:
The factory springs weigh 8 lbs each,
The factory shocks are 7.25 lbs.
This is a total weight of 15.25lbs per side, or 30 lbs total

Viking coilovers fully assembled per side are 10.75 lbs, 21.5 lbs total. A savings of another 8.5 lbs just from swapping to a much better performing shock and spring combination.

So, in total you are looking at 37 lbs in savings from the k-member and arms, 7 lbs from the manual rack, and 8.5 lbs from Viking coilovers. You can save a total of 52.5 lbs off the front of the car, without losing your a/c or anything else. That is a pretty serious gain for someone looking to gain a competitive edge, and promote weight transfer.

01ssreda4

iTrader: (96)

Very cool post. Thanks.

Chris25

iTrader: (1)

Good info.

Firebirdmuscle

iTrader: (16)

Very good info to put out. Maybe it won't be as many post about it now if they do a good search

BMR Tech2

iTrader: (5)

A little more info to add to this, for those trying to find all the weight savings they can from the front end. Here is a comparison of a stock power steering rack vs a manual pinto rack that we offer as a bolt in for these cars. There is a weight difference of 7lbs just in these parts. Plus another 10-11lbs from eliminating the pump, hoses, fluid etc that goes along with the power steering. So a total of close to another 20 lbs.




So with the addition of a tubular k-member, arms and a manual rack you are looking at saving over 50 lbs off the front of your car.

ramairetransam

iTrader: (18)

whats the road race k member weigh ?

BMR Sales2

iTrader: (40)

We don't have a road race specific k-member but we have quite a few guys that run our regular tubular k-member that road race their vehicles.

BMR Sales2

iTrader: (40)

I have been getting quite a few questions on weight savings with our parts so I will bring this back up to the top so people can check it out.

nddragon01

Excellent info on the suspension parts. Now the only question is: how many bones do I need to throw your way for a black k-member with LS1 motor mounts and black lower a-arms for a 2000 Trans Am? Any specials going on presently or in the near future?

Turns out I have a bad ball joint in the driver's a-arm, and the stockers are discontinued (oh darn, guess I'll have to upgrade).

Thanks!

BMR Sales2

iTrader: (40)

I can definitely help you out with that, give me a second and I will shoot you a PM.

nj02z

iTrader: (6)

Also on any vehicle driven on the street ,mild steel is much less prone to cracking compared to chromoly correct?

Zmg00camaross

iTrader: (11)

Cool info.

BMR Tech2

iTrader: (5)

Exactly correct. Mild steel will flex and give just a little to accommodate vibrations and abuse of street driving, where chromoly is very brittle, especially after being welded. Chromoly parts are proned to cracking around weld joints after prolonged street use.

To see an example of this, hold a standard plastic ink pen by the ends, and put pressure on the middle of it. It will bend and deform, but when you take the pressure off it will go back to its original state. Now try this with a pencil. The pencil will resist flexing with more pressure than the pen, BUT once it reaches yield point it will splinter and break. There is no going back to original state from there

BMR Tech2

iTrader: (5)

A little more info to add here, as far as weight savings on the front go:
The factory springs weigh 8 lbs each,
The factory shocks are 7.25 lbs.
This is a total weight of 15.25lbs per side, or 30 lbs total

Viking coilovers fully assembled per side are 10.75 lbs, 21.5 lbs total. A savings of another 8.5 lbs just from swapping to a much better performing shock and spring combination.

So, in total you are looking at 37 lbs in savings from the k-member and arms, 7 lbs from the manual rack, and 8.5 lbs from Viking coilovers. You can save a total of 52.5 lbs off the front of the car, without losing your a/c or anything else. That is a pretty serious gain for someone looking to gain a competitive edge, and promote weight transfer.

BMR Tech2

iTrader: (5)

Been getting a lot of questions about the weight savings of our front components lately, so I figured I would bring this back up to the top to be easier to find.

blackbyrd

iTrader: (14)

good read!

dailydriver

Are the Viking shocks a STREET and DRAG RACE ONLY type 'max weight transfer' damper (like the Strange and QA1s), or do they offer a multi-adjustable, balanced, made for turning left/right, and braking, road race/autocross compatible shock (like a lower cost Penske/Moton/Ohlins)??

JD_AMG

They're a non-gas charged drag shock made by the same guy who used to make QA1's. Their design is almost identical (at least the way the "adjustments" work.)

BMR Tech2

iTrader: (5)

Well, yes and no. Vikings offer a much wider range of compression and rebound valving than any other shock on the market, in finer increments. Most of how a shock performance comes down to how the stiff or loose the valving is and how well it is matched to the spring rate. We have several customers who are doing autocross and road course duties with their Vikings, and I have had no complaints thus far. We have been going through this in the Mustang market as well. Viking has become known for drag race related products, but that does not mean that is all they are capable of. There is another very large suspension sponsor on this site who runs Viking coilovers on their autocross car as well. It all comes down to properly matching spring rate and valving adjustment. I would not hesitate to use them on a handling application

Mike Morris

iTrader: (55)

Does the lower and upper front control arms kill the ride on the street? Already have the BMR Kmember but didn't do the arms since I heard issues of binding etc.