So I exploded my motor last month and now I'm planning on doing a LS swap and have been looking into the aftermarket K members. I have read the 2 best are UMI and BMR the problem with UMI is you can't run AC with a LS motor so there out. BMR you can't use factory A arms and I can't find if they alow the use of AC or not. And the reviews on here of Spohn are horrible. So what other brands have you guys used with good luck ?

 

Umi just requires you to relocate the ac to the top with commonly available conversion brackets.

 

Then I'm having to get all Custom AC lines I was kinda wanting to keep that factory but who knows I mite change

 

The problem is when keeping the stock location, you loose factory bracing between the frame and the k member on the passenger side. That's why UMI opted to not allow it. If the car is being used hard, its best to keep all the bracing possible

 

I used the holley bracket and all factory stuff worked

 

I'm using all the factory AC from a 4th gen. That's why I was wanting to keep the LS compressor where it is. Instead of having custom lines made but I mite have to. I can't find if BMR requires it moved or not. I just emailed them so we will see.

 

Call around town and see if guys can make custom a/c lines reasonably priced. I work in a hidden hole in the wall shop and guys are surprised how cheap we make and modify lines. If someone will help you it might help you make up your mind.

 

BMR got back in touch with me. There k member doesn't make you move the AC compressor. Have any of you guys delt with any of there products?

 

I have the BMR K-member with LSx stands. Tons of clearance to do anything you desire. Although the stands make it impossible to drop the engine in with the flywheel housing on the engine. I personally feel the BMR is flimsy and somewhat regret using it.

UMI does a better job of rigidity but eliminating AC was a bonehead move.

The new player on the block is Heidts and that is one serious K-member. Although it is so beefy that one has to wonder why not stick with the stock k-member and notch it for the AC?

 

I called Heids and talked to them for awhile and was very impressed definitely my favorite looking K member. The only sucky thing was they haven't tried a LS with a A/C compressor on it so they didn't know. He went threw a lot of Detail with me on why they did things the way they did and it made a lot of sense probably the way I will go even if you have to move the A/C compressor

 

Hi guys.

Thanks for mentioning UMI.

For A/C, correct on the relocation. These guys rock. http://www.kwikperf.com/

They know a lot about a/c and componentry above and beyond their brackets. Good source of knowledge.

You can use factory arms with our k-member but they do require a tiny bit of grinding in the bushing area on a non-load-bearing area. Literally just a few seconds to knock a tip off.

ramey

 

I second that. I was on the phone with Kwikperf and they were top notch. Really like there brackets a lot of thought went into those.

 

Follow up on this topic, I learned that Heidts puts 3 degrees of anti-dive into their K-member.

 

They say it helps the nose from squatting when hard breaking. I talked to them for close to a hour. So far I really like there K member and probably go with them. Not as much weight savings as UMI or BMR but they said they tried a bunch of there competitors K members and found some issues with them that is why they made it so much stronger BUTT you do lose weight savings. I'm not worried about that tho

 

They never tried there LS motor with a A/C compressor so they couldn't answer if the compressor had to moved or not

 

Taking weight off the bottom of the car isn't necessarily a good idea anyway. Raises center of gravity. When you're trying to improve handling of a car there is good weight and bad weight. K-member tends to fall in that good weight category.

 

Wow QwkTrip. Never thought about changing the center of gravity, most of us probably have a drag racer mentality with weight but I don't really drag race.

 

Anybody have a like to the heidts k member? I can't seem to find it and am curious

 

Attached is a link to the Heidts K-member. There is a bit of weight savings over the stock unit, but the biggest selling point is the antidive that's built in. We do that with all of our PRO-G front ends for people that will autocross or race their cars.

http://www.heidts.com/part/cf-402-19...-control-arms/

 

Mine is going to be used as a daily driver. Any problems with using you're unit ?

 

Not at all, it'll be great on the street too. The antidive just keeps it from squatting under hard braking so it's good on the street without any negative ride characteristics.

 

On the site it shows it not painted. Is that how it comes? That's fine if it is I'm just curious

 

It will come powder coated in black, we need to update that photo

 

Looks like the provisions for the factory front bracing have been removed? Looks like a pretty stout piece. Are spring perches available separately or what's the deal with them?

 

They told me the brace is built into the k-member and bolt to stock brace location. You re-use the stock a-arms. Their a-arms are for coilover only.

You can tell I've been looking into this. Only thing keeping me from buying one is I am not going to be an experiment for whether or not AC fits. Somebody else can go through that disappointment.

 

If it uses the stock triangular frame rail braces it wont work with ac.

 

I'm just going to get a A/C relocation bracket

 

good choice it solves a lot of issues

 

The stamped steel pieces are integrated and the spring perches are available in two kits, the CF-402 for the factory springs and there's an option for coilover also. Both stock or aftermarket arms will fit.

 

Updated links to the k-member with updated photos

http://www.heidts.com/part/cf-401-1-...over-k-member/

http://www.heidts.com/part/cf-402-19...bird-k-member/

 

Have you tried to fit the low mount 4th gen f-body air conditioning pump?

 

Sorry, we haven't fit any AC pumps to the k members

 

Ok thanks for the info. let us know when you know whether a LS motor with a low mount 4th gen A/C pump will fit or not since many people run that type setup. Thanks for showing the 3rd gen some love by developing some new performance parts options.

 

It will not work since the front triangular bracing is still there.

 

The pictures for both of these products look the same in these two links. Does the CF-402-1 come with spring perches?

The picture of the crossmember that comes with the Part #TFGP1 THIRD GEN F-BODY FRONT KIT PACKAGE 1 looks very different, but does look like the original picture from when these first appeared on your website. What has changed in the design?

The motor mounts in the picture will not work with a factory clam shell motor mount. What motor mount is required?

 

Bump. Would still like an answer to my question!

10 months later. Is that the kind of customer service Heidts delivers?!?

 

Makes you look like a helpless dumbass.

 

I bet if you actually called them you could get the answers your looking for.

 

It pretty clearly states in the description on the second link you posted, "works with factory struts and control arms, or tubular control arms and coilovers. So one would assume if it works with factory struts, that means it's designed for stock style springs.

 

You've added nothing to this conversation.