Tubular k-member on a street car

[TonyG]

I'm installing longtubes in a 99 2v GT, and will have the stock k-member off. I'm thinking about swapping to a tubular k. I'm particulary looking at the PA Racing K with the stock A-arms.

This is a street car, so I have several concerns. Can anyone chime in and answer a few questions:

(1) With the PA Racing k and stock A-arms, will the ride be harsher, noisier, bumpier etc.?

(2) Will I have to avoid taking hard turns to keep stress off the front end?

(3) Although I dont road race now, is road racing in the future completely out of the question, unless I get the "road race" k-member?


I've been debating whether or not to get the "road race" option with the extra bracing. But it adds 6 lbs and adds $150 to the cost. I'm already $800 into into my longtube project (headers, mide-pipe, coatings), and I'm not sure if I want to pay another $500 to lose 20 lbs.

Thanks

 

[Rickey_Bobby]

The UPR K member kit is $750 I believe and comes with the k member, a arms, bushings, coil over kit, and springs. I am running one and the quality is wonderful. Not a single issue after many track days at sebring.

while your under there, get some urethane motor mounts.

 

[Rickey_Bobby]

also, you NEED the coilovers, the after market k member doesnt have a spring perch.

 

[01BlkGT]

I'd go with the MM k-member and a-arms if I could do it over again. Having peace of mind is worth the extra expense imo, plus you get several added benefits such as increased wheelbase, etc. There are also K-member that either allow the use of the stock control arms or have tubular a-arms that have spring perches.

 

[TonyG]

also, you NEED the coilovers, the after market k member doesnt have a spring perch.

Some do. AJE and PA Racing, for example, have spring perches as an option allowing you to use the factory A-arms.

 

[Rickey_Bobby]

the increased wheelbase is a pain, doesn't aid anything, and in most cars, causes severe rubbing issues.

UPR is a great product. I have installed several of them on cars thet get the living crap beat out of them. I have gotten nothing but positive feedback from the people who are using them. Buying a fancy name doesn't always mean you get a better part.



but to each his own. Just my $0.02

I'd go with the MM k-member and a-arms if I could do it over again. Having peace of mind is worth the extra expense imo, plus you get several added benefits such as increased wheelbase, etc. There are also K-member that either allow the use of the stock control arms or have tubular a-arms that have spring perches.

 

[BennyBlown2v]

the increased wheelbase is a pain, doesn't aid anything, and in most cars, causes severe rubbing issues.

UPR is a great product. I have installed several of them on cars thet get the living crap beat out of them. I have gotten nothing but positive feedback from the people who are using them. Buying a fancy name doesn't always mean you get a better part.



but to each his own. Just my $0.02

That's just flatout wrong. Altering the wheel base shifts weight distrobution favorably. Moving the engine back, and the wheels forward is a good thing. UPR makes a drag product, it's not designed to take the rigors of ACTUAL road course racing (not just a few lap days here and there). Maximum Motorsports makes a quality product, so does PA racing, both of which work well in street cars.

 

[san~man]

I recall reading more than one post in the past about aftermarket K's bending when used on the streets. Most of the units out are designed for straight line track use, and don't do well when faced with potholes, driveways, and the other hazards our cars see on the streets.

MM wasn't one of them though....

 

[stangman]

i have a d&d k-member in mine & have had 0 issues with it. the only draw back was there is a little more road noise, due to there being less mass underneath to block the noise

 

[TonyG]

Thanks Stangman.

 

[Yellow2002GT]

I have the PA racing tubular K, tubular arms and strange 10 way adj coilovers......the fitment is great but really suggest getting some different coil overs.......they are quite noisey........

"ED"

 

[jeffnoel]

What about longevity? Aren't these k-members made for racing either straight line or twisties? Has anyone put some real miles on them 20-30K miles or more? I put 16K on mine last year and just wonder if they would stand up to daily driver punishment?

 

[01BlkGT]

Well I've had mine for almost 30k now and haven't noticed any problems with it. I try and check for cracks when I can, but haven't noticed anything. That doesn't mean I'm not worried about it though, but it seems to be holding up pretty well to the rigors of DD, drag, and a bit of auto-x.

 

[stangman]

Well I've had mine for almost 30k now and haven't noticed any problems with it. I try and check for cracks when I can, but haven't noticed anything. That doesn't mean I'm not worried about it though, but it seems to be holding up pretty well to the rigors of DD, drag, and a bit of auto-x.

x2

i've had mine for 30k & do the same in checking for cracks & what not & it's been all good

 

[forum155pl]

I have had my UPR for about 9 months now with 0 problems.. it seems to feel a little better in the twisties.. and there is nothing worse then spokane streets .. so i give the UPR kit a

 

[cooper58d2002]

If I were going to go with a k-member for the street I would look for a mild steel one do to the constant and excesive vibration and stress put on a street car. The mild steel will flex rather than crack as with crome-moly.

 

[Rickey_Bobby]

That's just flatout wrong. Altering the wheel base shifts weight distrobution favorably. Moving the engine back, and the wheels forward is a good thing. UPR makes a drag product, it's not designed to take the rigors of ACTUAL road course racing (not just a few lap days here and there). Maximum Motorsports makes a quality product, so does PA racing, both of which work well in street cars.

Have YOU actually measured the affects from moving the wheels foward? Or just read up on it.

-There are NO actual added cornering abilities, faster 60' times, or shorter braking times due to moving the front wheels foward such a small amount. IF what your saying is true, a car with an altered wheel base should completely walk all over mine in the handling department. UPR has taken me over 1.0G @ 95mph on street tires.... thats saying something there....
-Also, My car has seen over 5,000 miles of road course racing thus far. It has been through several transmissions, engines, wheels, brakes ect... Still using the UPR k member. It has not bent even after leaving the track @ 100mph and bending wheels, dropping the front hard on a missed shift during a drag launch, and 2 years of hard daily driving.

 

[BennyBlown2v]

Have YOU actually measured the affects from moving the wheels foward? Or just read up on it.

-There are NO actual added cornering abilities, faster 60' times, or shorter braking times due to moving the front wheels foward such a small amount. IF what your saying is true, a car with an altered wheel base should completely walk all over mine in the handling department. UPR has taken me over 1.0G @ 95mph on street tires.... thats saying something there....
-Also, My car has seen over 5,000 miles of road course racing thus far. It has been through several transmissions, engines, wheels, brakes ect... Still using the UPR k member. It has not bent even after leaving the track @ 100mph and bending wheels, dropping the front hard on a missed shift during a drag launch, and 2 years of hard daily driving.

...loooooool yeah I've been in many, and driven a few, aftermarket K-member mustangs.... It's not about skid pad numbers, it's about balance, reactivity, and drivability - not to mention ability to greatly alter static alignment while retaining in-spec dynamic alignment (correctly designed K-members reduce bumpsteer, ackerman angle, brake dive, etc.). Have you actually measured to make sure your K-member hasn't bent, or had it magnafluxed to inspect for hairline cracks, imperfections, and general faults? Honestly, no offense, but a race car is alot different than a street car...and there is no reason to support a product that simply is not designed for the rigors of open track racing. I'm sure UPR would be the first to admit that they did not intend for their product to be used on a daily-driver basis, and that it is not optimized for road course racing.

 

[Rickey_Bobby]

...loooooool yeah I've been in many, and driven a few, aftermarket K-member mustangs.... It's not about skid pad numbers, it's about balance, reactivity, and drivability - not to mention ability to greatly alter static alignment while retaining in-spec dynamic alignment (correctly designed K-members reduce bumpsteer, ackerman angle, brake dive, etc.). Have you actually measured to make sure your K-member hasn't bent, or had it magnafluxed to inspect for hairline cracks, imperfections, and general faults? Honestly, no offense, but a race car is alot different than a street car...and there is no reason to support a product that simply is not designed for the rigors of open track racing. I'm sure UPR would be the first to admit that they did not intend for their product to be used on a daily-driver basis, and that it is not optimized for road course racing.

So your are comparing completely different cars with different K members that are most likely NOT sharing IDENTICAL suspension setups, or even tires and wheels. You can NOT compare like that. Hell, one guy could have had a low tire in front and made the worlds best K member understeer like a stock V6 mustang.

Car is measured and re-aligned before every race OBVIOUSLY.

Magnafluxed your getting a bit rediculous for the sake of an arguement.

My point is, you can spend $100's more for a name brand and you will see negligible improvement. That is all.

 

[BennyBlown2v]

So your are comparing completely different cars with different K members that are most likely NOT sharing IDENTICAL suspension setups, or even tires and wheels. You can NOT compare like that. Hell, one guy could have had a low tire in front and made the worlds best K member understeer like a stock V6 mustang.

Car is measured and re-aligned before every race OBVIOUSLY.

Magnafluxed your getting a bit rediculous for the sake of an arguement.

My point is, you can spend $100's more for a name brand and you will see negligible improvement. That is all.

I have it available to me... My dad does all the medical work for Panther Racing, and I'm connected to Chip Ganassi through my work...

UPR is a name brand - it does great for what it's designed to do; and that is, be light, and help you go fast...in a straight line.