I have a 84 Trans am. I am taking everything apart and cleaning it and repainting it. my question is should i go a head and put a tube k member with a arms in it or just say with the stock. I will be replace all bushings and most of the hardware. The car will be mostly driven on roads and maybe sometimes draged maybe. And taken to car shows. any info on this will help.

 

Im in the same boat as you but when it comes down to it I ask myself " Is it worth it and do I really need it" I drive my car on the street all the time when it works LOL. I have come to the decision if I do an LS1 swap in the next few years I wil do it but for now I dont need it as it doesnt do anything for me. Sure its lighter but for a street car its just not worth it to me at the moment.

 

Complete waste of money.

 

I know what you mean. Thats what i am try to figure out if it is worth it. More then likely it will just have a 350. but i dont what to get down the road and have her almost done or done and wish that i had gone that route. Just dindt know if they are any pros and cons to it.

 

You'll have a lot more clearance for long tube headers if you go that route..

 

I put a BMR K member and tubular A arms on my 92. I lost an inch or two of ground clearance and the engine sits about an inch forward also. Lots more clearance for long tubes and distributors, carbs.

 

https://www.thirdgen.org/forums/engi...54-swap-4.html

The pictures of the kmember and a arms start at post 157

 

if its primairly a street driven car, a tubular k-member is not always the best idea, they done take impacts quite as well, IE sliding into a curb or similar, same with the a-arms. Unless you just want the look, i would say just clean-up the stock parts, put in new bushings and hardware and call it a day.

Dont forget to put new motor mounts in while its apart. Maybe new brake lines too if they are rotted

 

I think the strongest postive attribute of the tubular stuff is the weight savings. Its alot lighter than the stock stuff. Also the suspension action is a lot firmer and more positive. Lost all that rubbery feel.

I've clobbered mine a couple times already and its no worse for wear. The roads in california are horrible.

 

Say that after you drive through MO. They rank 40th or so as far as best roads in the US go. They terribly suck in MO.

 

I'm from mississippi and I drive from there to california every year and CA roads are by far the worst. I've never been to MO but if they are worse than that then you have my sympathy man. whew!

 

jersey roads are pretty pitiful too

 

unless you're looking to save every pound, want something pretty underneath, and need to make room underneath, a tubular kmember's not a necessity. i'd love to have one myself, but i've got other things that should come first in making the car go fast and handle well

 

Yeah the price for a full tubular front setup is a little much for some folks but for me I think it was worth it. Cost about 1200 all said and done. If you haven't driven a car that has one you should check it out.

 

I have a tubular K member and a-arms here, and I live in Winnipeg, your roads are a fantastic compared to ours, which actually name our potholes in this city, one of the radio stations here have a competition to who can find the biggest potholes.
I have had no problem with the car on these streets, I also have 2 inch drop spindles on the car

 

the car feels better. there is more room. you get rid of about 45lbs and the parts are trick..

its the parting with the bucks to install all the trick parts. but then you have room to add the 572 ci big block

 

How does it feel "better".. Like it what way?

 

i say take off the stock one blast it and powder coat it. i have done both and will stick with the factory k member from now on.

 

seems like a waste to not take the time to mod the stock one a little before putting it back in

 

Could I ask what steered you back to the stock K member? I'm interested as I've never heard a drawback from the tubular ones.

 

how could u mod the stock one?? weld on a brace or something?

 

Id like to know why you went back to the stock one as well. Im looking to do this mod way down the rd and would like to know all the pros and cons

 

So far the pros I've noticed from my full tubular front end was
1 lower engine for lower cg and more distributor/firewall to engine clearance
2 much more header clearance to floorboards/firewall/a arms
3 Easier to remove oil pan with big block installed.
4 significantly lighter than oem parts
5 much smoother/more accurate suspension action.

The only con I can think of was
loss of ground clearance to header collector. My collector strikes the road during (ahem) spririted driving , or going over some inclines. (If i had big block springs on the car I doubt it would bottom out)

 

it really depends on what you are looking to get out of the k-member. Im adding weight jack plates, shaving the rear control arm mounts to gain some room, and adding a couple little braces. Also clearancing the center for exhaust clearance and attempting to lighten it up a bit at the same time.

 

i dont see how this would happen. The stock k is much beffier than any aftermarket k ive ever seen, and the suspension all attaches the same way, so i fail to see how it would be any smoother or accurate. If anything, some of the more drag oriented tubular k-members have less bracing than stock, and IMHO would be more prone to flexing than the stock k.

 

What makes of K-Members and A-Arms are you guys using by the way. Really looking into doin the swap as i just got a new car and its next to clean as a 3rd gen can be from Canada can be.

 

When i swapped my stock one out for the Spohn K member there was only a 4 lb difference between the 2.

The tubular A arms might weigh a bit less but this isn't something i'd do for the weight savings. It's great if you need clearance for a bigger oil pan or headers though.

 

If I remember correctly, the factory K-Member weights around 45lbs, the Racecraft Roadrace K-member with extra bracing and spring perches weights 23.5lbs, and both my tubulars a-arms together weighed less than 1 factory a-arm. So there is a weight savings.

Between those changes, going with a rack and pinion, taking out the air cond. and relocating the battery to the back, Aerospace Street front brakes and the racecraft spindles, I took 250 -300 lbs out of the front of my car

 

geting rid of the stock K member. i say do it.iv done it. and Love the Look And feel of the Car. more room. looks Better. and with just the poly bushings feels better..Iv also got rid of the stock springs and went with coil overs. so i can set ride high to anything I Like.

shaved off about 38lbs off the front by doing this also.
stock K member 40 lbs

sphon K Member 28lbs

just that was a bit more then 4lbs..lol

 

I am leaning towards the sphon K-member and A-arms as it seems to be the most popular around and Ive heard they are better on the street than BMR as they are more a racing oriented K-member.

 

in the last 18 years iv put only 54.000 on my Z28. so the car has always been a blast to drive.

never driven it like the Dukes of Hazzard. so its always been tight to drive. after installing the K Member & tube A arms/coil overs. it felt Better. car is use for street and drag. and has always held up Fine. 100%

 

The reason is because all the stock parts are stamped peices. So they flex and twist to a degree. Also most cars are still running rubber bushings. The BMR stuff is all polyeurathane with brass sleeves.

When I did my K member and a arms it was smoother, firmer, and had a lot better road feel. I can't speak for the others but BMR stuff is tops in my book.

 

Can you really notice flexing of the stock piece? It seems that nobody really knows exactly what is stronger or can prove it.. I have tubular a-arms but I felt no difference when installing them cuz I had poly bushings in my stock a-arms. I have the stock k-member and to me, 20lbs off the front is not worth the cost of this piece, but atleast I would know that I am not missing out on some great product that makes the chassis more rigid and stronger and handle better, etc.

 

--Anything that is a stamped peice is going to have more flex in it than a DOM tubular replacement. That ammount may not be huge or even noticable but it is there. Nature of the beast. Nobody is going to put a giant torque wrench and an angle finder on a stock/aftermarket a arm and note the difference in deflection based on input. Those who do will likely never share that info.

--The difference in weight between the stock K member/ a arms and the bmr peices was much more than 20 pounds. I could barely move the stock stuff without help. I could lift the entire aftermarket setup with one arm easily. Your comment is reasonable however. The value of any modification is subjective. If you don't care about weight or extra clearance then poly bushings would really be all you need.

--Its not like swapping over to tubular front suspension is gonna make you go to church, push the preacher over and put this stuff in his place. But it was a very noticable difference to me. Given, I do drive a lot more aggressively than 90 percent of people out there. On a daily driver going to the grocery store, It would not be worth the money.

 

ok, i was refeering to the stock k, but yes, different bushings will affect smoothness.

however, fwiw, the stock k member and a-arms, with delrin bushings, will be just as smooth and the aftermarket ones. Wether the stock a-arms do or do not have flexing issues, is a different story and im sure you can find people on both sides of the fence.

oh, and Devastator, did yoi make different motor mounts to lower the engine, or did that just happen with the new k? that would seem like a design issue for a "stock replacement" piece, unless it was an option/custom job of somekind?

 

agreed 100%. Weight reduction is rarely a bad thing, but it all boils down to price.

I just picked up a stock k and a-arms for a project and yes, its a pretty heavy POS to lug around, not a 2 man job, but still heavy.

 

No I used the supplied motor mounts. It came with moroso solid engine mounts. I tried using the stock engine mounts and they wouldn't fit for some reason. Can't remember what it was. I'm not sure if the other tubular K members lower the engine like the BMR one does. You'd have to ask some folks who have other K members.

 

Im looking for an aftermarket K-Member and A-arms now. Anyone in the Canadian area know where i can get one as the local speed shops around here do not deal with spohn at all. Thanks

 

You can always order direct from the manufacturer. Spohn, UMI, BMR, etc all have websites

Curious, why dont the local shops deal with Spohn?

 

It's true! Even here in Montreal, the place I goto (Zekes Performance) does not deal with Spohn, although they have used their products in various customer cars as in mine (SFCs, PHB, LCA, etc.). It is strange for sure cuz Spohn makes good stuff. I think it's more along the lines of them using the bigger names in the biz that have been around longer and have more products for a larger variety of cars.

 

what other companys make k-members for our cars besides spohn and bmr. I can think of any besides them

 

The answer is literally less than 6 inches up on your screen..... lol

 

UMI doesnt make one for a 3rd gen and I knew those places i was looking for other ones as well.

 

Racecraft, AJE, etc

Seriously do a search

 

Is it just me or does the AJE look somewhat like the Stilettho K-member that Racecraft makes? Both are race only, but sure are light.

 

OK so I have the chance to get a BMR K-member and A-Arms but am still tossing the idea around if a should or not. Can anyone help me decide in the pros and cons of doin the swap. Thanks

 

I would do some reading on the forum, this has been debated a 100 times, then you will havethe information so you can make up your own descison, that is what I did and choose to put one in

 

go back a few pages. I discuss it with a few others.