Tubular K-Member
04-05-2004, 06:41 AM
#52
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Car: 92 Z28
Engine: Boosted LSX
Called vern at Pro fab at 4:30 to order mine. he said he didn't have any powder coated in stock. No biggie I said I'll coat my own. he said Oh ya. and started asking me tons of questions on Powdercoating....lol. I bet he BSed for about an Hour about coatings before he finally took my Credit card info. lol.
He just bought a Line setup to do all his own PCing.
anyways he said it would ship out in the AM. well I'm in OHIO not to far away but Damm, It showed up the same day he shipped it.
EXCELLENT SERVICE.
He just bought a Line setup to do all his own PCing.
anyways he said it would ship out in the AM. well I'm in OHIO not to far away but Damm, It showed up the same day he shipped it.
EXCELLENT SERVICE.
04-05-2004, 05:10 PM
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Car: 04 Xtreme Blazer
Engine: 4.3L V6
Transmission: 4L60E
Originally posted by TPl383
Called vern at Pro fab at 4:30 to order mine. he said he didn't have any powder coated in stock. No biggie I said I'll coat my own. he said Oh ya. and started asking me tons of questions on Powdercoating....lol. I bet he BSed for about an Hour about coatings before he finally took my Credit card info. lol.
He just bought a Line setup to do all his own PCing.
anyways he said it would ship out in the AM. well I'm in OHIO not to far away but Damm, It showed up the same day he shipped it.
EXCELLENT SERVICE.
Called vern at Pro fab at 4:30 to order mine. he said he didn't have any powder coated in stock. No biggie I said I'll coat my own. he said Oh ya. and started asking me tons of questions on Powdercoating....lol. I bet he BSed for about an Hour about coatings before he finally took my Credit card info. lol.
He just bought a Line setup to do all his own PCing.
anyways he said it would ship out in the AM. well I'm in OHIO not to far away but Damm, It showed up the same day he shipped it.
EXCELLENT SERVICE.
I think I which one I'm going with for my LT1 swap
04-06-2004, 07:46 AM
#56
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Car: 92 Z28
Engine: Boosted LSX
Originally posted by Kandied91z
looks good, scary how close to pa it is....i also recieved mine non powdercoated and did it myself.
looks good, scary how close to pa it is....i also recieved mine non powdercoated and did it myself.
Names Sound Famil. Performance Automotive/PRO FAB
(PA)
For thos eof you worried about street/auto-X driving. Ask or Tell him your looking for a Auto-X version and he will make one out of thinker materials and brace it up more.
I myself didnt want to wait to have one made. and he had mine instock uncoated.
04-06-2004, 07:29 PM
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I've read about alot of people on this site worried about running CM K-members/A-arms on the street so I asked Jason from PA and he said this:
"Chromoly for street is OK as long as it's not a thin wall chromoly product (which most are for weight) I'd never use anything thinner than . 095 for street use being that the tubing is thinner than the weld and that's where it wants to crack, I use all . 095 on our chromoly units just for this I've got many customers that have used these for there street cars with no problems (I also will replace any chromoly unit for as long as you own it if there is any problem)."
"Chromoly for street is OK as long as it's not a thin wall chromoly product (which most are for weight) I'd never use anything thinner than . 095 for street use being that the tubing is thinner than the weld and that's where it wants to crack, I use all . 095 on our chromoly units just for this I've got many customers that have used these for there street cars with no problems (I also will replace any chromoly unit for as long as you own it if there is any problem)."
04-12-2004, 09:49 AM
#59
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Car: 1985 Chevy Camaro IROC-Z
Engine: 350ci from 79camaro
Transmission: 5 speed manual on lsd
Could someone tell me exactly what bolts I'd need for putting on a PA racing k member and a arms. What I think I need are :
6 bolts for mounting the k member to the chassis
2 bolts for the rear mounts of the a arms
2 bolts for the front mounts of the a arms
4 washers for a arm bolts
4 nuts for a arm bolts
I take it that the PA racing parts come with bushings but no bolts?
Cheers,
Si. :lala:
6 bolts for mounting the k member to the chassis
2 bolts for the rear mounts of the a arms
2 bolts for the front mounts of the a arms
4 washers for a arm bolts
4 nuts for a arm bolts
I take it that the PA racing parts come with bushings but no bolts?
Cheers,
Si. :lala:
04-12-2004, 10:07 AM
#60
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Metal, i know you are not from PA, but you might ask them what gains there are from using Chromoly if they are not using thin-wall, the reason for using chromoly is for weight, the gains here come from thinner wall tubing that mild steel.
there was a very similar discusion to this on a road-racing board that i frequent, i copied and am going to paste a response from one of the members, he is an engineer who specialises in stress analisys.
there was a very similar discusion to this on a road-racing board that i frequent, i copied and am going to paste a response from one of the members, he is an engineer who specialises in stress analisys.
Even assuming the welding/heat treating is done properly and throwing that out....
When you have two similar designs, one mild steel and one chrome moly, with the chrome moly being lighter they are very different parts. The chrome moly is lighter because the tubing used has less wall thickness. You can do this and maintain the ultimate and yeild strengths of the original part because the material itself has a higher yeild and ultimate strength. You don't get that for free, however. You lose two things:
Stiffness: Chrome moly is no stiffer than mild steel. It is possible to design a part with extra gussets, tubes, etc, that can regain the overall stiffness and still be lighter but if the designs are the same the one using the thicker material will be stiffer.
Fatigue Cracking: Even though the part may be ultimately as strong or stronger it's because of the strength of the material. The reduced thickness (how else are you going to get it to weigh less?) means you're operating at higher stress levels. Now this can be done well with a staff of Engineers and an R&D budget that allows you to test parts to many life cycles but such isn't usually the case for the parts we're talking about.
This matters because of the higher stress levels. Fatigue life goes down with higher stress--it's a logrithmic curve too which means a small increase in stress can dramatically shorten life. That's why it's so hard to design a part that goes just far enough (weighs the least amount possible) without going too far (fails before expected) and what all that money for the Engineers and Testing gives you.
Various alloys of steel have a certain stress level which is refered to as its fatigue limit. This is the stress level at which the S/N curve flattens out. Basically, at this level of stress the material can endure infinite cycles and never crack. All one needs to do is design the part such that every nook and cranny of it never sees a stress level higher than this limit and it should basically last forever.
But, like I said, that's the hard part. Here is the beauty of mild steel for those building parts that don't have the kind of budget to pay Engineers or facilities for proper testing. It's weak. Yup, that's what's so good about it. It has a yeild strength very close to its fatigue limit. What does this mean? Build a part, go thrash on it and try to break it. If you can't even bend it, it isn't likely to develope fatigue cracks. Done. Sell part.
Various Chrome Molys do have a higher fatigue limit than mild steel. But not as much higher as their yield strengths. Their yeild and ultimate strengths are often much higher than their fatigue limits. That's what makes things tough. With a Chrome Moly part, you can build it, thrash the crap out of it and not even be able to bend it. So you declair it good, start selling it...and a year later your customers are sending them back to you with cracks all over them. Sure, you may have tested the parts in even more harsh conditions--but you didn't do it long enough. The stress levels were high enough to fatigue the thing but not bend it or break it.
Finally, with all else being equal, the thinner the material the faster cracks grow once they appear. In other words, there is less time between a crack appearing and the part failing for you to find it and fix the part.
So, for something like a K-Member, I'll take mild steel. For an all-out racecar that will be meticulously inspected often (better not have any powdercoating on it!) and for which you expect to replace parts frequently, and/or you have absolute confidence that the people building the part spent big bucks on the design & testing, yeah sure. Lose the weight.
But if the two designs you are looking at are virtually identical except for wall thickness and material, it's a safe bet that the mild steel version will have a fatigue life many times as long as the chrome moly version. But it weighs more. Your choice.
When you have two similar designs, one mild steel and one chrome moly, with the chrome moly being lighter they are very different parts. The chrome moly is lighter because the tubing used has less wall thickness. You can do this and maintain the ultimate and yeild strengths of the original part because the material itself has a higher yeild and ultimate strength. You don't get that for free, however. You lose two things:
Stiffness: Chrome moly is no stiffer than mild steel. It is possible to design a part with extra gussets, tubes, etc, that can regain the overall stiffness and still be lighter but if the designs are the same the one using the thicker material will be stiffer.
Fatigue Cracking: Even though the part may be ultimately as strong or stronger it's because of the strength of the material. The reduced thickness (how else are you going to get it to weigh less?) means you're operating at higher stress levels. Now this can be done well with a staff of Engineers and an R&D budget that allows you to test parts to many life cycles but such isn't usually the case for the parts we're talking about.
This matters because of the higher stress levels. Fatigue life goes down with higher stress--it's a logrithmic curve too which means a small increase in stress can dramatically shorten life. That's why it's so hard to design a part that goes just far enough (weighs the least amount possible) without going too far (fails before expected) and what all that money for the Engineers and Testing gives you.
Various alloys of steel have a certain stress level which is refered to as its fatigue limit. This is the stress level at which the S/N curve flattens out. Basically, at this level of stress the material can endure infinite cycles and never crack. All one needs to do is design the part such that every nook and cranny of it never sees a stress level higher than this limit and it should basically last forever.
But, like I said, that's the hard part. Here is the beauty of mild steel for those building parts that don't have the kind of budget to pay Engineers or facilities for proper testing. It's weak. Yup, that's what's so good about it. It has a yeild strength very close to its fatigue limit. What does this mean? Build a part, go thrash on it and try to break it. If you can't even bend it, it isn't likely to develope fatigue cracks. Done. Sell part.
Various Chrome Molys do have a higher fatigue limit than mild steel. But not as much higher as their yield strengths. Their yeild and ultimate strengths are often much higher than their fatigue limits. That's what makes things tough. With a Chrome Moly part, you can build it, thrash the crap out of it and not even be able to bend it. So you declair it good, start selling it...and a year later your customers are sending them back to you with cracks all over them. Sure, you may have tested the parts in even more harsh conditions--but you didn't do it long enough. The stress levels were high enough to fatigue the thing but not bend it or break it.
Finally, with all else being equal, the thinner the material the faster cracks grow once they appear. In other words, there is less time between a crack appearing and the part failing for you to find it and fix the part.
So, for something like a K-Member, I'll take mild steel. For an all-out racecar that will be meticulously inspected often (better not have any powdercoating on it!) and for which you expect to replace parts frequently, and/or you have absolute confidence that the people building the part spent big bucks on the design & testing, yeah sure. Lose the weight.
But if the two designs you are looking at are virtually identical except for wall thickness and material, it's a safe bet that the mild steel version will have a fatigue life many times as long as the chrome moly version. But it weighs more. Your choice.
04-12-2004, 11:45 AM
#61
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What have you guys been doing for springs? With that much weight reduction there must be some serious coil spring cutting going on!
Those K-Members look as if a hard corner would cause A LOT of flex! Can anyone tell after an install if their front end seems more loose?
Those K-Members look as if a hard corner would cause A LOT of flex! Can anyone tell after an install if their front end seems more loose?
Last edited by CamaroMike; 04-12-2004 at 02:00 PM.
04-13-2004, 10:13 AM
#62
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Well guys,
Thanks to this Topic and the great information, I just ordered a Complete Front end kit from ProFab Racing. 877-782-6470
Vern is hooking me up with a K-Member, A arms, Bump steer kit,
Coil Over kit, Power Rack & Pinnion (Fox Body Cobra mustang Quick ratio), And a new steering shaft. I ordered C/M .095 tubing thickness. They are doing one of their special Road Race/ Autocross K-Members, & A Arms with extra bracing, for Extreme duty.
They say this complete kit will take off 175 Pounds Off the front of my car!!!
Since my car weighs 300 Lbs more in the front to start with, I will next be replacing my Stock Steel hood with a Fiberglass one. That should almost get me to a 50/50 ratio.
I will keep you posted on the install....
Thanks to this Topic and the great information, I just ordered a Complete Front end kit from ProFab Racing. 877-782-6470
Vern is hooking me up with a K-Member, A arms, Bump steer kit,
Coil Over kit, Power Rack & Pinnion (Fox Body Cobra mustang Quick ratio), And a new steering shaft. I ordered C/M .095 tubing thickness. They are doing one of their special Road Race/ Autocross K-Members, & A Arms with extra bracing, for Extreme duty.
They say this complete kit will take off 175 Pounds Off the front of my car!!!
Since my car weighs 300 Lbs more in the front to start with, I will next be replacing my Stock Steel hood with a Fiberglass one. That should almost get me to a 50/50 ratio.
I will keep you posted on the install....
04-13-2004, 02:22 PM
#63
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yeah the major weight reduction really has caused me problems with proper spring choices...beyond that i have no problems taking hard corners, donuts or figure 8's with mine.
still waiting on all my c/m to crack as it's all worked out very well for me....just hope it doesn't happen all at once!
still waiting on all my c/m to crack as it's all worked out very well for me....just hope it doesn't happen all at once!
04-13-2004, 06:37 PM
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Car: 89 Camaro
C/M =(Crome Molley)
My Eibach Springs I currently have up front are 714 Lbs per inch.
I was told a good rule of thumb when relocating the spring to a coil over is to devide your current spring rate by 2 to get the new rate.
I want it a bit stiffer than the eibach so I went with a 400 Lb coil over to begin with. Vern at Profab said if I need a different rate He will just swap me until I get the right one. (I need a very stiff rate for autocrossing) BTW I run Koni Yellow, Adjustable struts.
My Eibach Springs I currently have up front are 714 Lbs per inch.
I was told a good rule of thumb when relocating the spring to a coil over is to devide your current spring rate by 2 to get the new rate.
I want it a bit stiffer than the eibach so I went with a 400 Lb coil over to begin with. Vern at Profab said if I need a different rate He will just swap me until I get the right one. (I need a very stiff rate for autocrossing) BTW I run Koni Yellow, Adjustable struts.
04-13-2004, 07:07 PM
#66
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Car: 02 WS6 White/Ebony
Engine: LS1
Transmission: T56
Axle/Gears: Stock 3.42
Do the koni yellows work with the coil over kit? You may want to check with Kandied about what will work, I think he had some issues with different struts being different diameters.
04-14-2004, 01:04 AM
#68
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Car: 86 IROC
Engine: 305 TPI
Transmission: Auto
I am still a litlle confused about the usage for the tubular k-members and steering racks. The tubular k-members are good for street, strip, autocross. Not good for roadrace? Are the steering racks you all are getting for strip cars, or are these street cars? Is there a rack that would be good for roadrace and street, or would the stock steering be better? I want to eventually get in to roadracing and trying to get an idea what components i need to get.
04-14-2004, 08:22 AM
#69
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Car: 89 Camaro
I am new to this discussion, But here is what I have learned.
My car is not Just for drag racing. It is used for "All of the above", Drag, Road race, Autocross, Street and whatever else. I had heard of problems with CM cracking, But like most everyone else I have never actually seen it happen. As was stated earlier in the thread, I was told that It is "possible" to have cracking if too thin of tubing was used. Profab uses only .095 wall thickness tubing on the CM units. I was also told by Vern that he would build me a unit that had extra bracing to ensure it would hold up to the extreme abuse of Road racing, and autocrossing.
As for the Rack & Pinnion. most dragracers do not want a Power steering rack, so they use a Manual rack Made for a Pinto.
I on the other hand I need power steering. The options as I understand them are to either use a 4th gen F Body rack, Or use a Fox body mustang rack. I was told the problem with the 4th gen F Body rack is that it is a couple of inches too long on either side to be a direct bolt in on the Third gen. That can cause a major problem with bumpsteer so I was told.
The easier way to go is to use a rack & pinnion from a 93 Fox body Cobra mustang. It has a quick ratio comparable to the one on my IROC and is much easier to retrofit.
This is all new to me so I will have to let you know how it works out.
My car is not Just for drag racing. It is used for "All of the above", Drag, Road race, Autocross, Street and whatever else. I had heard of problems with CM cracking, But like most everyone else I have never actually seen it happen. As was stated earlier in the thread, I was told that It is "possible" to have cracking if too thin of tubing was used. Profab uses only .095 wall thickness tubing on the CM units. I was also told by Vern that he would build me a unit that had extra bracing to ensure it would hold up to the extreme abuse of Road racing, and autocrossing.
As for the Rack & Pinnion. most dragracers do not want a Power steering rack, so they use a Manual rack Made for a Pinto.
I on the other hand I need power steering. The options as I understand them are to either use a 4th gen F Body rack, Or use a Fox body mustang rack. I was told the problem with the 4th gen F Body rack is that it is a couple of inches too long on either side to be a direct bolt in on the Third gen. That can cause a major problem with bumpsteer so I was told.
The easier way to go is to use a rack & pinnion from a 93 Fox body Cobra mustang. It has a quick ratio comparable to the one on my IROC and is much easier to retrofit.
This is all new to me so I will have to let you know how it works out.
04-14-2004, 08:48 AM
#70
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Car: 02 WS6 White/Ebony
Engine: LS1
Transmission: T56
Axle/Gears: Stock 3.42
The problem with the fox mustang rack is it cuts the turning radius. By how much.....I don't know. What is the exact ratio of it, and how many turns lock to lock is it? Hawks has a power rack kit that I believe uses a different brand of rack.
What's the bumpsteer limited to with the cobra rack? And is it low enought that it can be eliminated with a bumpsteer kit?
Also, will the cobra rack allow larger/wider size rims to be used without rubbing? I assume it will, but definate answers would be nice to have.
As for chromoly, I see no advantage in it if using the same thickness as mild steel. For one, you're not saving any weight. If mild steel is strong enough they use the same wall thickness cm as mild steel, then I'd be paying extra money for something don't need. With the potential for it to develop stress cracks. I want powdercoating and I don't have a magnafluxing machine to check for stress risers (you wouldn't be able to safely catch them with the naked eye) and even if I did, I wouldn't want to do it anyways. I'm gonna go with a mild steel version, and at least for now I'm gonna keep the quick ratio steering box. I may switch to a power rack later.
What's the bumpsteer limited to with the cobra rack? And is it low enought that it can be eliminated with a bumpsteer kit?
Also, will the cobra rack allow larger/wider size rims to be used without rubbing? I assume it will, but definate answers would be nice to have.
As for chromoly, I see no advantage in it if using the same thickness as mild steel. For one, you're not saving any weight. If mild steel is strong enough they use the same wall thickness cm as mild steel, then I'd be paying extra money for something don't need. With the potential for it to develop stress cracks. I want powdercoating and I don't have a magnafluxing machine to check for stress risers (you wouldn't be able to safely catch them with the naked eye) and even if I did, I wouldn't want to do it anyways. I'm gonna go with a mild steel version, and at least for now I'm gonna keep the quick ratio steering box. I may switch to a power rack later.
04-14-2004, 09:43 AM
#71
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Car: 90 irocz
Engine: 350tip
Transmission: 700r4
the stock power steering and rack wont work?
Also can you please post pics of the autox/road race k member/arms when you get them. Im very curious as to the differences, as it will be the make or brake for me buying it.
Also can you please post pics of the autox/road race k member/arms when you get them. Im very curious as to the differences, as it will be the make or brake for me buying it.
04-14-2004, 03:04 PM
#72
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i've put mine through some pretty stressful things and haven't had any problems but i guess i'm just lucky.
as for the springs they never told me to devide it in half like that. i was given a standard spring rate in the 2.5x10" id that was 250lbs and i had no adjustment but up and the car rode like hell.
switched to 150lb eibach ers and the car had excellent adjustment but it was rather soft in the front so now i'm on 200's.
however i'm running bilstein hd struts with custom coilover sleeves so my id is in fact 3" instead of the more common 2.5" check the diameter of your koni strut to know what size you need to go with. 2.5 and 2" has alot more available with even more room for tires but the support wasn't there that i like so that's why i modified the bilsteins.
as for the springs they never told me to devide it in half like that. i was given a standard spring rate in the 2.5x10" id that was 250lbs and i had no adjustment but up and the car rode like hell.
switched to 150lb eibach ers and the car had excellent adjustment but it was rather soft in the front so now i'm on 200's.
however i'm running bilstein hd struts with custom coilover sleeves so my id is in fact 3" instead of the more common 2.5" check the diameter of your koni strut to know what size you need to go with. 2.5 and 2" has alot more available with even more room for tires but the support wasn't there that i like so that's why i modified the bilsteins.
04-14-2004, 04:22 PM
#73
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KANDID91z,
Thank you for your help. I went and measured my Koni Struts. They are aprox. 2.25 O.D. I suppose the 2.5 I.D. Springs are what I need.
I need a very stiff spring rate, A little bit stiffer than My current Eibach rate. If I am using the 2.5" by 10" spring what rate would you recommend?
BTW I don't think I could go with a 3" spring because I am using 17 By 9 Inch wheel With 275/40/17 tire. There isn't but maybe 1.25 inches between the strut and the tire now...
Thanks again.
Thank you for your help. I went and measured my Koni Struts. They are aprox. 2.25 O.D. I suppose the 2.5 I.D. Springs are what I need.
I need a very stiff spring rate, A little bit stiffer than My current Eibach rate. If I am using the 2.5" by 10" spring what rate would you recommend?
BTW I don't think I could go with a 3" spring because I am using 17 By 9 Inch wheel With 275/40/17 tire. There isn't but maybe 1.25 inches between the strut and the tire now...
Thanks again.
04-15-2004, 01:55 AM
#74
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tire size does make a difference. however i was running the 3" setup with my 9.5 275/40/18 z06 wheels with no problems.
as for spring rate i can't help you with that as i'm still struggling with the setup and have decided to change it for something different.
all i can say is they are not related. you go too stiff and you'll not only have problems but lack of adjustment. if the shop your dealing with is willing to do spring swaps like mentioned above go that route. as for me i never discussed that aspect with pa since i changed over to art morrison style setup and i now have 3 sets of springs i'm not using through trial and error.
do some searches on the internet and try to find someone who can help you better with spring selection. when you find the answer let me know too! i'm happy with my 200lb setup but it's slightly different and i have alot of weight reduction...
as for spring rate i can't help you with that as i'm still struggling with the setup and have decided to change it for something different.
all i can say is they are not related. you go too stiff and you'll not only have problems but lack of adjustment. if the shop your dealing with is willing to do spring swaps like mentioned above go that route. as for me i never discussed that aspect with pa since i changed over to art morrison style setup and i now have 3 sets of springs i'm not using through trial and error.
do some searches on the internet and try to find someone who can help you better with spring selection. when you find the answer let me know too! i'm happy with my 200lb setup but it's slightly different and i have alot of weight reduction...
04-23-2004, 11:37 PM
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Vern and Jason used to be PA racing partners, they had a falling out and went theyre separate ways. Jason kept the PA RAcing name and vern went to Pro-Fab performance automotive. The difference is vern makes and designs all the parts himself whereas jason takes the same design and has someone else build them so usually you will get better pricing through vern(ProFabRacing). So now everyone knows why the parts look the same, vern designed them. Great products by the way
04-24-2004, 02:32 AM
#76
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Car: 1999 Z28
Engine: LS1
Transmission: 6 Speed
Axle/Gears: 9" 4.11 Truetrac
Originally posted by Z RATED IROC
I am new to this discussion, But here is what I have learned.
My car is not Just for drag racing. It is used for "All of the above", Drag, Road race, Autocross, Street and whatever else. I had heard of problems with CM cracking, But like most everyone else I have never actually seen it happen. As was stated earlier in the thread, I was told that It is "possible" to have cracking if too thin of tubing was used. Profab uses only .095 wall thickness tubing on the CM units. I was also told by Vern that he would build me a unit that had extra bracing to ensure it would hold up to the extreme abuse of Road racing, and autocrossing.
As for the Rack & Pinnion. most dragracers do not want a Power steering rack, so they use a Manual rack Made for a Pinto.
I on the other hand I need power steering. The options as I understand them are to either use a 4th gen F Body rack, Or use a Fox body mustang rack. I was told the problem with the 4th gen F Body rack is that it is a couple of inches too long on either side to be a direct bolt in on the Third gen. That can cause a major problem with bumpsteer so I was told.
The easier way to go is to use a rack & pinnion from a 93 Fox body Cobra mustang. It has a quick ratio comparable to the one on my IROC and is much easier to retrofit.
This is all new to me so I will have to let you know how it works out.
I am new to this discussion, But here is what I have learned.
My car is not Just for drag racing. It is used for "All of the above", Drag, Road race, Autocross, Street and whatever else. I had heard of problems with CM cracking, But like most everyone else I have never actually seen it happen. As was stated earlier in the thread, I was told that It is "possible" to have cracking if too thin of tubing was used. Profab uses only .095 wall thickness tubing on the CM units. I was also told by Vern that he would build me a unit that had extra bracing to ensure it would hold up to the extreme abuse of Road racing, and autocrossing.
As for the Rack & Pinnion. most dragracers do not want a Power steering rack, so they use a Manual rack Made for a Pinto.
I on the other hand I need power steering. The options as I understand them are to either use a 4th gen F Body rack, Or use a Fox body mustang rack. I was told the problem with the 4th gen F Body rack is that it is a couple of inches too long on either side to be a direct bolt in on the Third gen. That can cause a major problem with bumpsteer so I was told.
The easier way to go is to use a rack & pinnion from a 93 Fox body Cobra mustang. It has a quick ratio comparable to the one on my IROC and is much easier to retrofit.
This is all new to me so I will have to let you know how it works out.
how much did the power rack & pinion setup cost you? and was it more expensive to get the beefd up road racing K member made?
04-25-2004, 08:53 PM
#77
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Car: Kitt
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Are the Pro-Fab K-Member and others a drop in deal? I wanted to drop in a tubular K-Member before the LT1 swap for clearence issues. i.e. header, and accessory clearence. I don't want to get one if I have to modify a lot of other things first to make it work.
What about the front springs. I don't think I remember seeing spring perches??
What about the front springs. I don't think I remember seeing spring perches??
04-25-2004, 09:54 PM
#78
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Car: 92RS
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Got my stuff a week or so ago, It bolted right in, no tweaking needed. I got a pic while it was temp installed.
04-25-2004, 10:36 PM
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Car: '82 Z28
Engine: 350
Transmission: TH400 4,000 stall
Axle/Gears: Currie 9", 4.56 gears
Are you able to still use the K-member as a jacking point? Or are you limited to using ramps to get the front in the air from now on.
04-25-2004, 10:44 PM
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I dont think you are supposed to jack on the tubular k-member, i sure as heck won't. I'll just have to do one side at a time. Oh well, mine is getting used to being up in the air!
04-26-2004, 02:16 PM
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Originally posted by EvilCartman
Are you able to still use the K-member as a jacking point? Or are you limited to using ramps to get the front in the air from now on.
Are you able to still use the K-member as a jacking point? Or are you limited to using ramps to get the front in the air from now on.
Steve
04-26-2004, 07:51 PM
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Car: '82 Z28
Engine: 350
Transmission: TH400 4,000 stall
Axle/Gears: Currie 9", 4.56 gears
Was thinking, if I ever get one I'd make a saddle with a rubber lining. Make it about a foot in length and that would drop in place of the jack pad. That way it would spred out the load a bit and not mar the powder coating.
04-26-2004, 09:59 PM
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Originally posted by Slush92RS
Got my stuff a week or so ago, It bolted right in, no tweaking needed. I got a pic while it was temp installed.
Got my stuff a week or so ago, It bolted right in, no tweaking needed. I got a pic while it was temp installed.
04-26-2004, 10:28 PM
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Car: '99 Trans Am, '86 Camaro
Engine: LS1, Scrap
Transmission: T56, T5
Axle/Gears: 3.42 Stock ZT, 3.42 Open
I noticed alot of discussion earlier in the thread about the ability of these tubular K-members to handle stress and arguments over whether they should be street driven... are any of the commonly available tubular K-members able to stand up to serious autocross? I'd like to move to coilovers, but I need something that's going to be bulletproof too
04-26-2004, 11:06 PM
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there isn't anything bullet proof but obviously i can understand where your coming from. for serious use i would just consult the builder.....that or add the needed triangles when you recieve it which is what most do.
i've seen plenty of them run at the track with no problems but they were weekend toys not full out auto-x cars.
i've seen plenty of them run at the track with no problems but they were weekend toys not full out auto-x cars.
04-26-2004, 11:35 PM
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Car: 02 WS6 White/Ebony
Engine: LS1
Transmission: T56
Axle/Gears: Stock 3.42
AJE uses bigger pipe then the PA or Pro-Fab one. I'd trust it more for a dedicated road race car. NO....I haven't used either, I'm just saying what I would do. Comparing both by pictures and after speaking to both Vern at Pro Fab and Anthony Jones. I'd feel much more confident with a mild steel road race version of AJE's for that application. If I was building a drag car...yeah I'd go with the Pro-Fab moly one with coil overs, and rack, and liteweight brakes. If you're not going to extremes and have to loose all that weight...it would be pointless to get the moly k-member. Vern uses the same wall thickness 4130 as the mild steel, so it's gonna weigh the same as the mild steel.
Also, since the strut towers were never designed to support the pressure of a coil-over setup, especially with the added stress of autoX, I'd recommend a weld-in style weight jack kit from Ground Control and whatever caster/camber plates you like (spohn/alloy, ground control, or J&M). Lets you set corner weigt or adjust height for whatever stance you like. If you went the coilover route and roadraced it....I'd definately add structural support in the towers, and I don't mean just a strut tower brace. Food for thought anyways!
Also, since the strut towers were never designed to support the pressure of a coil-over setup, especially with the added stress of autoX, I'd recommend a weld-in style weight jack kit from Ground Control and whatever caster/camber plates you like (spohn/alloy, ground control, or J&M). Lets you set corner weigt or adjust height for whatever stance you like. If you went the coilover route and roadraced it....I'd definately add structural support in the towers, and I don't mean just a strut tower brace. Food for thought anyways!
04-26-2004, 11:59 PM
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good point....i'm still waiting for my struts to come shooting through the towers. never seen it done, never heard of it either but that doesn't mean it can't happen right?
04-27-2004, 12:23 AM
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Car: 02 WS6 White/Ebony
Engine: LS1
Transmission: T56
Axle/Gears: Stock 3.42
Yeah it'll happen, and the springs will launch into orbit around the earth! I bet you didn't know that?
I have enough courtesy to not turn this thread into a flame war with you, but I will make one rebuttal based on fact.
Now, from a common-sense stand point:
The strut towers are nowhere nearly as much of a load bearing part as the frame-rails are, of which the crossmember is attached to, which in stock form (read: as designed by the engineers) the coil springs sit inside and the majority of the load of the front suspension is applied to that point. Now the strut towers do handle some load of course, after all the strut serves the same purpose as the upper A-arm would, but not nearly as much as the spring. So of course it will hold together, but it will develop flex over time that won't give you optimum handling (remember, the thing that is the main goal in road racing).
I guess Karl Hunter, and Sam Strano, And Lou Gigliotti (all of which have much experience in successfully road racing 3rd gen f-bodies) are all as foolish as I because they didn't convert to front coil-overs? Sam and Lou won national SCCA titles because they didn't have the brilliant idea to run front coil-overs?
The defense rests their case your honor!
I have enough courtesy to not turn this thread into a flame war with you, but I will make one rebuttal based on fact.
Now, from a common-sense stand point:
The strut towers are nowhere nearly as much of a load bearing part as the frame-rails are, of which the crossmember is attached to, which in stock form (read: as designed by the engineers) the coil springs sit inside and the majority of the load of the front suspension is applied to that point. Now the strut towers do handle some load of course, after all the strut serves the same purpose as the upper A-arm would, but not nearly as much as the spring. So of course it will hold together, but it will develop flex over time that won't give you optimum handling (remember, the thing that is the main goal in road racing).
I guess Karl Hunter, and Sam Strano, And Lou Gigliotti (all of which have much experience in successfully road racing 3rd gen f-bodies) are all as foolish as I because they didn't convert to front coil-overs? Sam and Lou won national SCCA titles because they didn't have the brilliant idea to run front coil-overs?
The defense rests their case your honor!
04-27-2004, 01:09 AM
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Car: 02 WS6 White/Ebony
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My bad Jeff, I thought you we're being sarcastic. I guess I have had a hair trigger lately. Too many smartasses got ahold of me and turned me into a defensive bastard! LOL!
I smacked myself on the back of the head for ya!
I smacked myself on the back of the head for ya!
04-27-2004, 01:28 AM
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no problem....i wouldn't run a coilover for real autox without major modifications with our cars, forget about how it holds; the whole car just feels different.
however for weekend occasional stuff it works good.
however for weekend occasional stuff it works good.
04-27-2004, 02:41 AM
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Car: '99 Trans Am, '86 Camaro
Engine: LS1, Scrap
Transmission: T56, T5
Axle/Gears: 3.42 Stock ZT, 3.42 Open
Yeah, I fully intend to add some structure to the strut towers.. no way I'd try to support the entire front end with that sheet metal 
But yeah.. uncoated mild steel version of the AJE with some extra support welded in.. could work out rather well.. hadn't been thinking along any simple lines. whoops.
I'd think the coilovers would have much greater potential than the stock strut setup, but *shrug* ... if it's possible to get better cornering from the stock suspension geometry, sure as hell be cheaper.. I'm not against the thought
But yeah.. uncoated mild steel version of the AJE with some extra support welded in.. could work out rather well.. hadn't been thinking along any simple lines. whoops.
I'd think the coilovers would have much greater potential than the stock strut setup, but *shrug* ... if it's possible to get better cornering from the stock suspension geometry, sure as hell be cheaper.. I'm not against the thought
04-27-2004, 06:12 AM
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Originally posted by TechSmurf
I'd think the coilovers would have much greater potential than the stock strut setup
I'd think the coilovers would have much greater potential than the stock strut setup
04-27-2004, 07:24 AM
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Well, if there was actually a CM tubular K-member with stock style spring pertches that was designed for roadracing, then I might consider getting one. Anyone have any experience with this? I would also go for CM tubular A-arms but stick with the stock spring / strut setup. Combined with aluminum heads thats an easy 100 pounds off the front end.
04-28-2004, 07:39 AM
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Car: 92 Z28
Engine: Boosted LSX
when I ordered mine and talked to Vern at Pro Fab he said he can make one for auto -x out of thicker material and better braceing for auto-x. I didn't want to wait so I just ordered the regular one for standard spring perches.
I took it to a Local fabricator who has worked for nascar and Indy to check it out. See if it was worth the $$ of If I should send it back and have him Fab me one up. (he wanted to see one in hand also) Well he asked what i paid for it and I said Guess. he said Welll it looks great and will do fine for what i wanted. a Weekend cruiser with occasional Bad Ohio roads. and Guessed I paid around 480 for it.
I bought a Uncoated one so all the welds could be checked out. and I powder coat myself anyways.
ANYWAYS 2 thumbs up for the PRO FAB one.
I took it to a Local fabricator who has worked for nascar and Indy to check it out. See if it was worth the $$ of If I should send it back and have him Fab me one up. (he wanted to see one in hand also) Well he asked what i paid for it and I said Guess. he said Welll it looks great and will do fine for what i wanted. a Weekend cruiser with occasional Bad Ohio roads. and Guessed I paid around 480 for it.
I bought a Uncoated one so all the welds could be checked out. and I powder coat myself anyways.
ANYWAYS 2 thumbs up for the PRO FAB one.
04-28-2004, 10:49 AM
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Car: 92RS
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Axle/Gears: 10 bolt,3:73's
Originally posted by tamatt27
So it's a direct bolt in deal? Did it come with all the bolts and all hardware?
So it's a direct bolt in deal? Did it come with all the bolts and all hardware?
04-28-2004, 08:59 PM
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Car: 91 Mustang SS/O 10 tire car
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Reply to JIMS406RS
Just to set the record straight last I check Pa Racing made 100% of there parts in house as well. And no matter what you might of heard anytime there is split there will be words. I myself can tell you that no one person designed any of PA's units @ one time it was a group effort and it's sad that it went down the way it did. And both guys did work for AJE back in the day.