I personally wouldn't trust a tubular K-member for prolonged street use. If it's an occasional driver, that would be something else. The access and weight savings are certainly attractive. But AFAIK, even the people who make these don't advertise them for street use, do they?

Rich Krause

 

I agree with you rskrause.

 

Per BMR's website:

BMR Tubular K-members are designed to provide a lightweight alternative to the factory k-member as well as provide additional clearance for aftermarket headers and turbo systems. Our unique design on our V8 models feature integrated frame stands that replace the factory cast iron frame stands. This additional weight reduction allows us to use larger diameter tubing and thicker mounting plates for additional strength over the competition. This means that you can use the k-member for street use, road race, autocross, or drag strip use without worrying about long term fatique.

This is their advertising, not necessarily fact, but it states it's for street use and should not be a fatigue issue.

 

I've had 3 different PA k-members on my car. The first one I put in was one of their first ones made. It was on the car a few months, started having alignment problems and found a broken weld where the pass side lower a-arm bolts in.

http://home.mindspring.com/~w0442/si...s/P1010029.JPG

This one was mild steel. I called Jason @ PA and he immediately shipped me the new model (in the pic above) which did have additional welds and looked alot better. This one was mild steel as well.

When I got it I ran into the same problem as speedmiser. It was basically impossible to get a mount bolted to it because one of the main tubes was in the way. Take a look at the clearance in the pic below.

http://home.mindspring.com/~w0442/si...s/P1010030.JPG

So, I called Jason again and he offered to send me the best they had at no additional cost. A couple days later I received a chromoly race version. It is in the car now and haven't had any problems with it in over a year.

I have had one issue that has been there with all three though. I run the Hooker LTs and the damn passenger side does not have enough clearance. One of my header tubes is dented in and my nice coating is now rusting away.

The most important factor for me when choosing between mild steel and chromoly was the fact that in the event I were to have an accident.... mild steel would bend and chromoly will snap. I preferred bending over breaking which is why I initially ordered the mild steel. I ended up with chromoly and am happy for the weight savings yet I still have the thought in the back of my mind about what will happen if it were to snap in an accident.

So, you can see I been dealing with PA quite a bit. Jason is great to deal with and will work with you to make things right. I even had the opportunity to meet up with him while he was visiting our local track in Bradenton, FL and he offered to walk out to the parking lot and have a look at it right there.


Overall....I wish BMR had come out with their k-member a little sooner. I am not unhappy with PA since they stood behind their product yet BMR is only 20 minutes down the road for me and have seen first hand the quality of work that goes into their products. If the need to replace it ever comes up I will go to BMR.

 

Rich,

I respect your opinion and have for years so I had some concerns after your post. I called BMR directly and spoke with Frank. I asked him the question specifically about the use of these in street cars. Besides the fact I have other BMR products, I have always found them to be a straight up vendor and my conversation today was no different.

BMR has sold about 400 of these units and 60 - 80% are on street cars without problems. They have not had weld failure issues or other problems from street use.

Now, I'm no dummy, I know any company is going to defend their products but I felt our conversation was frank and honest. He was more than willing to answer all my obnoxious questions and even acknowledge that it was fair to have these concerns and appropriate to ask the questions.

I am comfortable with their response and will be ordering mine today. If I have any difficulties with it, this group will hear.

Paul

 

Yeah, I looked at BMR's site and they do advertise them for street use after all. Maybe it will be fine. I don't know anything about their specific product, I do know of tubular K-members that have failed though (other peoples).

Maybe it's ok? The better access and lighter weight certianly is attractive.

Rich Krause

 

I've just installed the mild steel PA that uses stock motor mounts. I'm running a Canton pan and Hooker longtubes and there are no clearance issues. The welds were all fine and the PA was a quality product from all indications.

When I had mine built by PA (they were out of stock everywhere...) I asked the builder his recommendations and he said they tried to steer folks away from the units with the built-in motor mounts. The reason was that it made positioning the engine difficult because of the cowl. He said the stock mounts make install much easier and allow the engine to be pulled from the top if desired. He said that with the one-piece design, the engine had to come out from the bottom. Once you see how honking big and heavy the stock k-member is (and not particularly resistant to bending...) you'll definately want to lose it. It would make a nice anchor...

BTW: I love mine and would do it to any LT1 that already had the engine out. I used the BMR adjustable lower a-arms and the Global West non-adjustable upper arms with NAPA ball-joints ($68...)

 

Yup, I am. I helped with the build up of the ones with the older Canton oil pans (Canton now offers one that fits better in our cars). I had Brett make them with a bit lower steering rack mounts, it throws off the bumpsteer, but that can be easily corrected with a bumpsteer alignment kit. I will be installing some Jet Hot LT's soon, so I'll see how everything works together with the k-member, canton, and headers in terms of clearance.

For the brake lines, I just zip tied them to their proper location and haven't had any trouble with them.

________________
Rob
1994 Firehawk#319
11.83@120.61
Slightly Modified
1996 Blown V6
2002 Trailblazer
San Diego F-Bodies
"What do you mean, "I hurt your feelings"? I didn't know you had any feelings."

 

I have the BMR k-member with the LT1 motor mounts and lower a-arms on a daily driven street car, i've put almost 800 miles on it since its been in, the install was easy and very straight forward, it took me 2 months to do it, but thats because i kept ordering new parts while i had everything out and was waiting on shipping and all that jazz, all in all it was about 3-4hrs. worth of actual wrenching (i'm a beginner). clearance is excellent with my hooker longtubes they slid right in in about 30 secs from underneath, altho the passenger side rear mounting plate that the lower a-arm rod end mounts in and bolts to the frame touches one of the header primaries, it kind of dented itself slightly, no noises or anything coming from that area.
someone asked about the the driver side brake line and where it mounts, mine (i think all) came with a mounting tab that the line gets attached too on both sides, the only places i used zipties were on the a-arms for the ABS wires and the line that runs parellel with the power steering rack
I do have alot of squeaking coming from the front end, but i didnt grease any of the poly bushings, i think those are the culprit.
i havent had an alignment yet either, its hard finding somone around here that will do it since its "aftermarket"

anyway end verdict, I give it 2 thumbs up on quality of welds and powder coating (hugger orange), 2 thumbs up on ease of install, like i said i'm a beginner when it comes to modifying cars and i tackled this almost all by my self, 2 thumbs up on clearance and room for arms to get in there and change plugs (anything is better then stock)

Steve

 

i have used, and have seen chrome tubing used in street cars for 13 years, and you don't have to worry about it "snapping", it won't. i have heard all the myths about chome moly tubing "work harden" in street cars but i have also worked with and talked to some of the best chassis builders around, they all use chrome in street cars.

as for AJE stuff, beware that if you by the K-member you have to buy the A-arms, other companys, and stock ones don't fit. a friend of mine that runs an outlaw 10.5 car (86 camaro) bought one, and the art morrison arms he already had wouldn't even come close to fitting it. so he ended up having to waste money buying the AJE arms. he would have bought the PA or the BMR unit if AJE would have told him this up front.

 

I have the PA K member and A-arms on my 98. It has been nothing but a nightmare. Lot of problems with fit, could not be aligned, customer service poor (non-existent) and poor qualith rod ends on the A-arms. I have already had to replace one rod end. It was too short for proper alignment. Had to buy a female rod end and stud to get correct length. Even had to shim the shock up as it was riding on the passenger side A-arm and making noise.

I don't know what to tell you to buy but any of the others have to be better quality than the PA.

 

There are some interesting comments on chrome moly in this thread on Advanced Tech. Note in particular the factual info in the posts by OldSStroker and Eric Bryant.

 

Fred,

Do you know approxiamately how much additional weight can be saved on a track car with the AJE strut version?

-brent

 

Reviving...

any long term experiences with the k-members?

 

+12,000 street miles on mine, holding up fine so far, same for the lower a-arms! BMR stuff with LT1 motor mounts
and i have hit some NASTY potholes too, jacked up the car numerous times on the cross section of the k-member also with no ill effects

pleased so far i am