I was told that the Tubular K-Member is not as strong as the stock unit, and that its main purpose is just to reduce weight and give lots of clearance, and that the PA Racing unit is prone to breaking in a street-driven environment. Do any of you guys use this thing every day? Have you had any problems? I've already ordered mine from Thunder Racing, but the order is on hold for now. Thanks!

 

I think Guido has one on his car, among others, but his car isn't running yet......

Take a look at RoadTech their unit is much beefier than the PAR one, and they seem confident of their design. That's the one I have picked out for my front-end upgrade.

 

Thanks for the link. Their unit looks a bit beefier, and is a bit more $$$. I think I'm going to pass on the PAR K-Member and save the cash for the Road Tech. Thanks again!

 

Dont you HAVE to switch to a coil-over setup if you go with the Roadtech version? I seem to remember hearing this....I would go with this as well...but I dont want to spend the extra money on the coilover setup especially since I already have the struts and springs.

 

I'm not sure, but I doubt it. It sounds like you purchase the A-arms seperately, leading me to belive it will accept any stock-style A-Arms as well as their custom coil-over units.

 

not to sure about that....i know the PA Racing ones you had to pay extra to get the ones with the spring perches so you didnt have to convert to coilover...from the pictures...the Roadtech control arms dont have the spring perches...and i dont see anything about spring perches being an option.......and I dont see it being an option on the kmember either....and I dont see any spring mounts on the kmember...but all this is just guessing

 

Ahh, crap..... I didnt even notice that, lol. Why cant PA make their unit a little more stout and suitable for daily driving....

 

I talked to a guy at PA Racing, and he says that in 5 years, he's rarely seen anything happen to the K-Members, and if something does happen, he will repair the damage free of charge. He did say that for daily driving he reccomends using the Chrome Moly version. Can anyone vouch for his claims?

 

Yea I asked him also and he said that if it ever does break (which he doesnt think it will) he will fix it. He told me also the chromoly one is the best choice. (and thats good cause thats the one I was gonna buy anyways)

 

Hi, At this time I dont offer the k-member for stock springs .I was just under a car I have in the shop with my k-member and I will check to see if any clearance issues will come up using a stock control arm. The main reason for not using stock springs is most people who inquire are looking to save weight and ride height adjustability via the coil over set up. If there is enough interest for stock spring placement I may be able to fab some spring pockets. HTH

...John

 

Well, its a little too late for me to purchase your unit.... I just placed my order for a PA Racing Chrome Moly K-Member. Hopefully it lives up to his word. He sounded fairly confident that these things dont break, so hopefully I dont run into any problems.

 

Hi Scott

I have the PA Racing Chrome Moly K-Member on my 92 Z28 street car. I think you will like it.

Jerry

 

I don't see where the swaybar attaches
to your A-arms in your picture. Do you
have a different picture that shows the
swaybar?

Thanks. I have the Road Tech K-member.
Here's a link to some of my pictures of it.
http://207.53.239.181/~terry/K-member.htm
The swaybar attchment is the last pic on the page.

Just my opinion, but I did not care for the top mounting of the coilover spring in the PA design.
All the weight of the car is on the plate that
is on top of the tower held by 3 small bolts.
The Road Tech version uses a plate under the
strut tower to push upward. Just seems to
be a better method of distributing the stress
IMHO.

thanks.

T.

 

The A-arms on my car are home made all 4130 units with Global west del-alum bushings turned down to fit in them.

The front sway bar is not used on the street only the rear is on the car i try to run the car as light as i can.

Jerry

 

Interesting... I also used the GW
Del-A-Lum bushings, turned down.
Leaves a big pile of shavings doesn't it?

thanks,

T.

 

Thanks for re-assuring me, now I feel a little more comfortable using the PA K-Member. Impressive job on those A-Arms! I wish I had the skills/tools to make something like that... One more thing... When installing the GW Del-A-Lum bushings, how hard is it to make absolutely sure that the grease fitting hole lines up perfectly with the hole drilled in the A-Arm?

 

If you look closely at JerryWho's picture
above, you can make out a "channel" or groove
in the delrin insert. This is a 360degree
channel. As long as the zerk fitting is
lined up with this channel - no problems.

Here's some larger shots of the bushings.
http://207.53.239.181/~terry/gw_brng.htm

WHOOPS! I just realized you meant, the outter
shell. After you press in the shell, remove
the delrin insert & steel sleeve, then just
drill another hole using the zerk hole
as a guide....

(sorry for my confusion)

hth,

T.



hth,

T.

 

OK, I'm still a little confused, I'm probably overthinking this because I would hate to ruin a pair of $300+ A-Arms, and a set of $130 freakin bushings.... If I had my tubular A-Arms already, maybe this would be easier for me to think about. The process you described really only tells me how to line the hole up with the channel, but it also needs to be lined up in the other direction too, or I'll miss the fitting. When I drill the hole in the A-Arm, doesnt it need to be tapped so the fitting will fit into it? Or is the hole in the A-Arm just a pass-through, and the fitting still threads into the bushing? I have no idea how thick the A-Arm tube walls are since I dont have them right now.

 

Yeah, you're confused.

If you look here:
http://207.53.239.181/~terry/images/ctlarm4.jpg
You see the DAL(del-a-lum) bushings installed
in the stock A-arm. The zerk-hole is eliminated
(not really, but the threads are basically gone) when you turn down the outter shell to the
correct size to press into the tubual A-arms.
The zerk fitting is just screwed into the
steel tubular A-arm. The DAL bushing when
inserted into the tubular A-arm is NOT exposed
like in the above stock A-arm picture....

Clear as mud? (hope not)

hth,

T.

 

Got a question for you guys with the coil over conversion....what do you guys run in the rear? Just stock setup with cut springs..or aftermarket springs..or what? Now im seriously considering using the coilover setup on my project car....and change out my cut springs on the ttop with the eibachs I have sitting here. What are the benefits/drawbacks of a coilover design?

 

one more question....what is the weight comparison between the stock kmember and the road tech kmember...and the weight difference between the road tech kmember and the pa racing kmember?

 

The stock unit was 48 3/4 LBS with the bolts and brackets. The PA Racing Chrome Moly K-Member with motor mounts and no coil spring mounts is 19 Lbs.

Jerry

 

Ahhh, I see now. I Wasnt thinking about having to turn the bushing down to make it fit in the A-Arm... I wonder if the PA Racing A-Arm accepts stock size bushings, or if I'll have to get my bushings cut a little to make them fit.

 

to the best of my recolection my crossmember weighed about 32# with motor mounts. When I first made mine I had to decide a couple of things.

first - who is going to use it and for what reason?

well, most request I get for mine is for a "street car" that gets race on weekend. It had to take abuse on the street.

second - Is weight that big of an issue?

I dont think it is , I have always said if you want it light to go fast - take out dead weight, like the stereo or floormats. I would rather have a couple extra pounds of gussets to support the suspension.

third- material. Chrome moly or mild steel. I chose mild steel because of the extra cost of CM and the extra labor in T.I.G. welding a complete k-member. I would not suggest a C.M. suspension part unless it has been "normalized" there again more money. You will hear 10 different answers from 10 different people on this one, but that is what I was tought by an Aircraft airframe fabricator and that is what I go by.

so that is why mine is mild steel, and weighs more than PA Racings. I took into acount the fact that in the past I have seen parts break on both race cars and street car and it was usually because of a lack of reinforcement gussets ot support tubes. I am not gonna get on here and knock PA. stuff , there's is build from there design, mine is built from my design. HTH

...John

 

Road Tech it is then

 

Road Tech, would you be able / willing to start on possibly producing a tubular, yet strong, K member and A arms for those of us setup for road racing but not willing / able to go to the coil over setup ?

 

Yes, If you were to get yourself and one or two others to commit to an order I can do it. Might even be able to set it up with an adjustable spring perch on the K-member for weight jacking. If interested shoot me an e-mail....John

roadtechonline@yahoo.com






Road Tech, would you be able / willing to start on possibly producing a tubular, yet strong, K member and A arms for those of us setup for road racing but not willing / able to go to the coil over setup ?

 

Road Tech...another question...this time about your coilover conversion...does it use the rubber (i would switch to polyurethane) isolators like the stock springs do? From the pictures i've seen it looks like the spring just goes onto the bare metal on the bottom of the spring where the adjuster is and on the top where the spring meets the mount.....if this is how its setup..is there any problems with any type of noises or anything? I would think using a rubber isolator would be a good thing....any ideas?

 

mult68, Not sure about this but i believe you were in on the HMS strut mounts, which it seems to have been determined that the coilover kit will not work with them, if you were, are you possibly in for Road Tech's suggestion on the K member and A arms ? Im interested but it may be a month or so before I can put a deposit on it, what amount are we looking at and how many people Road Tech, for Tubular K and Front A Arms.

 

I am in the general location of PA Racing...about 20 minutes away.

I have talked to the guy that fabbed up the original design that PA Racing copied...even though they will tell you otherwise...the fella that did the original design oriented it to the straightline IHRA? guys that run stock bodied cars(Gary Rho and his 'Stang come to mind).

Anywho, I talked to him about making one for my IROC...and mentioned Road Racing...he said he'd have to stiffen his up and put an extra brace in it to get it to where he was comfy selling it to me. He didn't seem to think it was a big deal...but something he would want to look at.

PA Racing I believe haven't looked at it this way...unless they have changed their design from AJ Engineerings Design.

You also have to ask...OK, they are willing to fix it if it breaks...but are they going to cover the cost of fixing your car too if you smack a guardrail on that rough exit ramp when it breaks? I doubt it...

Better safe than sorry if it could mame me.

 

I cancelled my PA K-Member order guys, lets try to get this Road Tech version started!

 

Does your caster/camber plate work with a stock setup or is it mainly intended for your k-member coil over setup??

 

First, do a search online, there’s a reason why PA has an answer ready for what they will do if it breaks. There are pictures online of various mounts pulled out of the K-member tubing.

Second, yea, chrome molly is stronger then mild steel so you can make the part lighter by using thinner/smaller parts, but if your car is a street car, ask yourself what do you want to happen when you hit that 1 in a million car eating pothole, get pushed over a curb or run over a cinder block that fell off of a construction truck (I’ve run over half a semi brake drum before with a similar effect)? Chrome molly cracks on impact, steel deforms/bends. I would much rather have an AFU crossmember and the suspension still attached to the car so there is some chance of stopping it safely then having the suspension mount points crack and, well, try to leave the car.

 

you may have a point about i f you hit a block or someting in the road. but if you actually watch people swerving out of the way to miss something in the road or watch the road in front of you instead of just aiming your car you should be fine from debris. doing that made me avoid a truck tire laying in the middle of the freeway doing about 80 in my lowerd chrysler sebring. the truck behind me hit though and he went all the way across six lanes then back and almost into the other side into oncomming traffic that was a mess. but if you watch when you drive 80% of time you'll be safe.

 

Good luck.

When I hit the semi brake drum (it went under the car, got wedged between the K-member, oil pan and the ground preventing me from steering and stopping and crunching the oil pan) I had no chance.

There was a pickup truck between me and the semi, the brake drum flew off (which I couldn't see) and at least a major chunk of it went through the front end of the pickup clean through the radiator. First hint that I got that something was up was when my windshield was completely covered with antifreeze so I couldn't see out and then a second later when I got a loud thunk, a grinding noise and lost steering and braking (the brake drum actually picked the front end of the car off the ground when it got wedged down there). What seemed like 2 seconds later It broke up and I was able to stop the car and get it to the side of the road. the chunks behind me took out 5 tires on the next 2 cars behind me. All 4 of us ended up on the side of the road trying to figure out what happened, the semi never stopped.

The damage on the pickup was impressive, there was a notch taken out of the bumper, a hole clean through the grille, AC and radiator, the cooling fan... was gone and there was a hole through the hood.

 

wow that sucks i hate it when $hit like that happens but thats why i said 80% because some times you can't help it.

 

What about when the car in front of me ran over a brick, and didnt disturb it, and I couldnt swerve because there were cars on both sides on me.... I used to have a pic of my toasted oil pan, cant seem to find it now though

 

Road Tech K-member w/ coil-overs:

1) Is the coil-over kit just a spring perch modification to the stock type struts? (hope to retain my adjustable struts)

2) Is there any tire clearance problems with the coil-over springs, say like running 245's+ tires? (knowing alot of 1/4 mile cars run skinny tires up front would not see this)

3) Are the springs a off-the-shelf size? (can be bought from a Afco type place)

 

Road Tech K-member w/ coil-overs:

1) Is the coil-over kit just a spring perch modification to the stock type struts? (hope to retain my adjustable struts)

]some struts require some grinding to install the sleeve

2) Is there any tire clearance problems with the coil-over springs, say like running 245's+ tires? (knowing alot of 1/4 mile cars run skinny tires up front would not see this)

too many variables for me to tell you what fits.IE...brands of wheel

3) Are the springs a off-the-shelf size? (can be bought from a Afco type place)


standard 2.5" springs

 

Road Tech...what springs do you recommend for the rears when using your coilover setup?

 

and where is Princeton by the way? I may drive over there and have you install a rollbar if it isnt too far. Also check out our clubs website (www.nttga.org) Its a local DFW thirdgen club...but were also a part of (and co-founders of) the Texas Thirdgen Alliance......a collection of thirdgen clubs across Texas...so far we have Austin, Houston, DFW, and El Paso covered. Perhaps we could work out some sort of deal.

 

I am about 10 miles east of Allen-McKinney. if ou want to come out let me know so we can set something up.....John


and where is Princeton by the way? I may drive over there and have you install a rollbar if it isnt too far. Also check out our clubs website (www.nttga.org) Its a local DFW thirdgen club...but were also a part of (and co-founders of) the Texas Thirdgen Alliance......a collection of thirdgen clubs across Texas...so far we have Austin, Houston, DFW, and El Paso covered. Perhaps we could work out some sort of deal.

 

PAracing uses the same size tubing for both mild steel and chromoly.........chromoly is just a hair lighter than mild steel

Maybe instead of all this internet commenting...talk to the source. Jason/Vernon are awesome guys and will answer all of your questions

 

If any of you guys are interested in the Road Tech K-Member and A-Arms, please refer to this post: https://www.thirdgen.org/techbb2/sho...hreadid=132602

 

Guys, for street use you want to use mild steel. It is more flexible and can handle the added stress of street driving better, especially in the long run. Chrome-Moly is more rigid and if used on a street application, it will eventually crack (unless treated like Road-Tech mentioned). I have some experience in working with metals, as I am a mechanical designer. Also my Father is a welder, he used to fabricate those rubbish trucks you see around your neighborhoods, for over 30 years. He taught me all I know (relatively). I chose the PA-Racing mild steel version for my car (sorry Road-Tech, didn't know about you then. I might get one for my SS though ), which will be street driven daily and raced (Road Race/Auto-X) in the weekends.