Which Swap K member?
#1
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Car: 87 IROC,
Engine: 370 LSx With Boost
Transmission: 4L80E
Axle/Gears: S-60 with 3.50s
Which Swap K member?
Thinking of just finishing my fron in Susp and getting a Tubular K member. I have ground control weight jacks so I dont think i want to go coil over unless thats the way to go. Which K Member for a 95% street car? BMR, Spohn, or something else? I wasnt going to do this yet but the stock one is just so damn ugly to me.
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Car: 1991 RS
Engine: L03
Transmission: T5
Axle/Gears: 4.11
Re: Which Swap K member?
I've done a decent amount of research on this issue as the first thing I'm doing to my project is building out the suspension. My choice is going to be Spohn with Del Sphere Rod-ends. The Del Sphere should work great for a street/track setup. Spohn generally seems to use high quality materials overall.
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Car: 86 Trans Am, 92 Firebird
Engine: 408 sbc, 3.1L of raw power
Transmission: TKO600, T5
Axle/Gears: Moser 9", 3:70 trutac, 3:23 torsion
Re: Which Swap K member?
keep the weight jacks, they are the ****.
im doing this swap in my 92 one of these days, as of now im going to be using a stock k-member, cleaned up and lightened and modified, just because i really dont like any of the current k's out there. If i could take some features from all of them and roll them up into one "hybrid" k-member, then yes, but as they are currently, i'll pass.
im doing this swap in my 92 one of these days, as of now im going to be using a stock k-member, cleaned up and lightened and modified, just because i really dont like any of the current k's out there. If i could take some features from all of them and roll them up into one "hybrid" k-member, then yes, but as they are currently, i'll pass.
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#8
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Car: 1991 Z28 convertible built 3/1/1990
Engine: Cammed 6.0L LSX
Transmission: T56
Axle/Gears: custom Ford 8.8", 4.10 gears
Re: Which Swap K member?
keep the weight jacks, they are the ****.
im doing this swap in my 92 one of these days, as of now im going to be using a stock k-member, cleaned up and lightened and modified, just because i really dont like any of the current k's out there. If i could take some features from all of them and roll them up into one "hybrid" k-member, then yes, but as they are currently, i'll pass.
im doing this swap in my 92 one of these days, as of now im going to be using a stock k-member, cleaned up and lightened and modified, just because i really dont like any of the current k's out there. If i could take some features from all of them and roll them up into one "hybrid" k-member, then yes, but as they are currently, i'll pass.
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Car: 1991 Z28 convertible built 3/1/1990
Engine: Cammed 6.0L LSX
Transmission: T56
Axle/Gears: custom Ford 8.8", 4.10 gears
Re: Which Swap K member?
I don't have the a arms yet, I'm waiting till I have enough money to get the coil overs at the same time.
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Car: Formula
Engine: 6.0 LSX
Transmission: 4L60E
Axle/Gears: 9 Bolt 3:27
Re: Which Swap K member?
I have the a arms. Nothing changed. I'm still surprised on how close the tierods come to the member. Mine are not hitting but its going to come close when I turn lol. We'll find out!
Last edited by Mkos1980; 08-31-2010 at 08:52 AM.
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Car: 1989 IROC-Z, 1979 Malibu Classic
Engine: LSx 5.3
Transmission: MN12 6-speed, 4L60E
Axle/Gears: 4th gen 3.42
Re: Which Swap K member?
Good idea on the coil overs, I bought the non-coil over tubular a-arms and even the eibach sportlines were a complete bitch to install, and the tubular a-arms dropped my car about another 2" so now it's time to throw some new ball joints and bushings in the stock a-arms and sell the tubulars!
#17
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Car: 87 IROC,
Engine: 370 LSx With Boost
Transmission: 4L80E
Axle/Gears: S-60 with 3.50s
Re: Which Swap K member?
I'm surprised more people dont have the BMR unit. I guess i will end up going spohn and wait for A-Arms at a later date.
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Car: 1991 RS
Engine: L03
Transmission: T5
Axle/Gears: 4.11
Re: Which Swap K member?
It seems everyone has a different experience with the Tubular K-Members. I have done about 100 searches on this board about them, because I am determined to use all of your experiences to make the best decisions on my project. I've spoken to several of the vendors too, and I was very happy with how quickly Spohn got back to me with inquiries, and also how nice they were on the phone. But everyones experiences are different, being in the service industry on the technical side I know how it is, every day is different.
I am going with the spohn full front suspension minus the manual rack system (only reason I didn't go with it is because I understand its harder to maneuver the car in parking lots and things, is this true? I'll ask in another thread when its time to buy)
I'm with Nick here, I'm going to get the Tubular A-Arms with the Touring Coil-overs when I make the move.
I am going with the spohn full front suspension minus the manual rack system (only reason I didn't go with it is because I understand its harder to maneuver the car in parking lots and things, is this true? I'll ask in another thread when its time to buy)
I'm with Nick here, I'm going to get the Tubular A-Arms with the Touring Coil-overs when I make the move.
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Car: 1983 Firebird SE
Engine: C5 LS1
Transmission: 6 speed
Axle/Gears: 3.42
Re: Which Swap K member?
Just so y'all know. I have some Spohn 4130 tubular A Arms for coil overs. I will sell for less than the mild steel price. I first got Spohn stuff, but switched to BMR to get clearance for C5 A/C. Most of the stuff is gone, but I still have those A Arms.
#20
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Car: 1991 Z28 convertible built 3/1/1990
Engine: Cammed 6.0L LSX
Transmission: T56
Axle/Gears: custom Ford 8.8", 4.10 gears
Re: Which Swap K member?
You could have used them with the Spohn k member. They're all made to factory dimensions so you don't necessarily have to keep one particular brand.
#21
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Car: Currently have 3 cars and 1 truck.
Engine: 1970&92 Cams,both BBC's
Transmission: LS1 T-56 & PG w/vendor's
Axle/Gears: Built 10 bolt& 9inch w/spool
Re: Which Swap K member?
I'm using the Spohn K-member, with their tubular lower control arms, but I use PA racing's coil-overs. Everything fit,no problems, excellent build quality for both brands.
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Car: 1983 Firebird SE
Engine: C5 LS1
Transmission: 6 speed
Axle/Gears: 3.42
Re: Which Swap K member?
If you look at a BMR A Arm you see the support piece is at an angle.
#24
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Re: Which Swap K member?
Is there any danger in using tubular k-members for daily driving use? Some say stock design is stronger, some say tubular is stronger (i've seen pics of tubular cromoly snapping because they dont bend like steel does, they just break without warning, therefore making them only good for track racing and not for street.)
#25
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Car: IROC-Z
Engine: LSx
Transmission: T56
Axle/Gears: Fabbed 9"
Re: Which Swap K member?
Same here. Racecraft wins, hands down. Just do a quick search on Spohn's fitment. He probably corrected his jig tho... I hope so.
#26
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Re: Which Swap K member?
Hey Spike Z. nice restoration job by the way... I "dream" of doing that to my car!
Anyways, how is the Racecraft k-member holding up on Quebec roads? Does it provide a provision to mount the k-member triangle braces to the front frame? Looks like a good peice to me..
Anyways, how is the Racecraft k-member holding up on Quebec roads? Does it provide a provision to mount the k-member triangle braces to the front frame? Looks like a good peice to me..
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Car: 87coupe,91RS Camaro's, 00 Suburban
Engine: LSX427HO w/D-1SC and intercooler
Transmission: RPM Tremec T-56 Magnum
Axle/Gears: DTS 12bolt, 3.42
Re: Which Swap K member?
I used Bmr...when you line sht tires up... do it with out the springs in first..have easier movement if need be, Had to pull my BMR over to the passenger side...and raised tires to ride height.. works out great...even the 350 k with my lsx in it
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Car: 86 Trans Am, 92 Firebird
Engine: 408 sbc, 3.1L of raw power
Transmission: TKO600, T5
Axle/Gears: Moser 9", 3:70 trutac, 3:23 torsion
Re: Which Swap K member?
I dont like the fact that they notched the main hoop to clear the steering linkage after years of problems with the linkage hitting. The jig is wrong and should have been rebuilt, but they "half-assed" the repair solution. Also from time to time problems come up with the car lowering after the install, or the wheels sitting back further in the wells and rubbing. I'll pass on it.
bmr: thhe intergrated motor mount is nice, but AFAIK, no way to use solid mounts. stuck with poly.
no triangular brace provisions, and the main hoop is not 1 pc. probably not a huge deal, but not ideal in my book. The biggest probably i have with bmr in general, is that you cant get parts in glossblack without an extra charge. seriously??? its the most popular color next to red for suspension parts, why not offer it?
racecraft: overall pretty nice, but again, no brace provisions, and it appears to lack bracing in certain places. probably not an issue in a drag setup, but for a corner carving setup, it could use some work.
umi: doesnt have one....
anybody else make one?
#32
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Re: Which Swap K member?
"racecraft: overall pretty nice, but again, no brace provisions,"
Actually Racecraft does make one that has the extra bracing. I was going to get it but one of the extra braces would have interferred with my exhaust termination box so I just bought the standard version along with the tubular a-arms. The shop has it mounted in the car with the motor. I should be able to pick it up next week and take it over to an alignment shop to get it checked out.
Actually Racecraft does make one that has the extra bracing. I was going to get it but one of the extra braces would have interferred with my exhaust termination box so I just bought the standard version along with the tubular a-arms. The shop has it mounted in the car with the motor. I should be able to pick it up next week and take it over to an alignment shop to get it checked out.
#33
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Car: 92 Firebird
Engine: Supercharged 6.0
Transmission: T56
Axle/Gears: 8.8 3.73
Re: Which Swap K member?
spohn: i like the fact that they have the option to reuse the triangular braces on the front of the k-member to the frame.
I dont like the fact that they notched the main hoop to clear the steering linkage after years of problems with the linkage hitting. The jig is wrong and should have been rebuilt, but they "half-assed" the repair solution. Also from time to time problems come up with the car lowering after the install, or the wheels sitting back further in the wells and rubbing. I'll pass on it.
I dont like the fact that they notched the main hoop to clear the steering linkage after years of problems with the linkage hitting. The jig is wrong and should have been rebuilt, but they "half-assed" the repair solution. Also from time to time problems come up with the car lowering after the install, or the wheels sitting back further in the wells and rubbing. I'll pass on it.
I think the notch is a half-assed fix for a design problem. Why not tilt the main hoop back a few degrees. A-arm box would need to be trimmed a bit, but other K-member designs dont even use the box, just simple tabs. The notch only clears the tie rods at ride height and barely that. I had to jack up the front wheels to get the tie rods back on, they hit that bad
The main hoop is also about 2" lower than the stock K-member. I sent them an email and was told no one, even slammed cars ever scrapped. Well, first speed bump I went over must be the tallest in the country because I left powder coat behind on it
Wonder why the LSx specific K still requires the conversion mounts. With a single duty part, why not incorporate the mounts in there? Guess he cant milk the extra $85 out then then. It'd free up alot more room, not that it's at all tight with the tubular piece
On the plus side, the engine is in the exact same spot as the stock K-member. Accepted the stock A-arms no fuss, wheel appears in the same location, no noticeable difference in handling, powdercoating was very pretty, all welds appear high quality and consistent. No bird crap
#34
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Car: 87 IROC,
Engine: 370 LSx With Boost
Transmission: 4L80E
Axle/Gears: S-60 with 3.50s
Re: Which Swap K member?
So what i have gathered is that since i really dont want aftermarket A-Arms yet i should go with a Spohn and that seems to be the "best" all around...
#36
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Car: 87 IROC,
Engine: 370 LSx With Boost
Transmission: 4L80E
Axle/Gears: S-60 with 3.50s
Re: Which Swap K member?
DAMNIT... I want it to be strong as my car is no drag queen and will see mostly street action. Its just so damn big... Ugh.
#37
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Car: Formula
Engine: 6.0 LSX
Transmission: 4L60E
Axle/Gears: 9 Bolt 3:27
Re: Which Swap K member?
After my car settled, Mine was at the same stock height , but I will go back to the other poster and say that the wheels do sit back a tad farther in the wheel well. I dont know if thats and A arm problem or K-Member problem.
#38
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Car: 1991 RS
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Transmission: T5
Axle/Gears: 4.11
Re: Which Swap K member?
I have not heard that Tubular K-Members are no good for Auto-x or Road Racing, where are you getting your information? Could you direct me to some hard data that would indicate that they are only good for drag racing?
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Re: Which Swap K member?
Don't believe that b.s., tubular k-members(atleast Spohns)are ok to do anything a stock member can do, except maybe rock crawling.
#42
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Car: IROC-Z
Engine: LSx
Transmission: T56
Axle/Gears: Fabbed 9"
Re: Which Swap K member?
Just a quick update on my Racecraft K. After driving the car a lot this summer, I cant be more pleased with the piece. I pushed the car hard in corners, and launched the thing @ 5K+. I never felt the piece was "loose" or unsecured. The front end is stiffer then it ever was. My car is heavily modified with air bags on 4 wheels. This is one of the best part I ever purchased. Hell, you can even order them custom.
#43
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Car: 1991 RS
Engine: L03
Transmission: T5
Axle/Gears: 4.11
Re: Which Swap K member?
I am very open to argument here though as I don't OWN a tubular cross-member yet, but I've done a lot of reading and I'd love to see what others think.
#44
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Car: 92 Firebird
Engine: Supercharged 6.0
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Axle/Gears: 8.8 3.73
Re: Which Swap K member?
Don't believe that b.s., tubular k-members(atleast Spohns)are ok to do anything a stock member can do, except maybe rock crawling.
#45
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Re: Which Swap K member?
just buy a tubular k member for the cool factor lol I have the Spohn in my car, the only gripe I have is that the wheels do sit further back and im still trying to figure out the steering linkage binding. I have been told it is in Spohns tubular A-arm design and not in the k-member itself.
#46
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Car: 87 IROC,
Engine: 370 LSx With Boost
Transmission: 4L80E
Axle/Gears: S-60 with 3.50s
Re: Which Swap K member?
I ende up getting a Spohn K-Member from a guy locally. I'll let you know how it goes when the car is back together again. Thanks guys.
#47
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Re: Which Swap K member?
moving the wheel further back is not good for handling because it makes the weight on the nose even more far out than before.. See, these are the issues that prevent me from buying one. Steering binding, wheel not in stock position, bottoming out if too low, etc.. I plan on dropping the car 2" from stock so getting a tubular k-member seems to be a bad idea just from the bottoming out factor. I wish someone from Spohn would get on here and explain some of these things...
#48
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Re: Which Swap K member?
I'm kind of liking the racecraft unit, especially considering that it says it's designed to work with their 2" drop spindles, which will give you the lower height without all the suspension geometry issues.
The one thing I find odd is that I don't see the road-race LS k-member offered in chromoly. Maybe I just missed it.
The one thing I find odd is that I don't see the road-race LS k-member offered in chromoly. Maybe I just missed it.
#49
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Re: Which Swap K member?
moving the wheel further back is not good for handling because it makes the weight on the nose even more far out than before.. See, these are the issues that prevent me from buying one. Steering binding, wheel not in stock position, bottoming out if too low, etc.. I plan on dropping the car 2" from stock so getting a tubular k-member seems to be a bad idea just from the bottoming out factor. I wish someone from Spohn would get on here and explain some of these things...