Late C3 Suspension / Handling- Biggest Bang-for-the-Buck Improvement?
01-10-2017, 08:11 PM
#21
Le Mans Master
The primary reason we wish to limit roll is to help best maintain the integrity of the contact patches on all four tires by avoiding excessive dynamic alignment changes. This can be achieved with bar or spring, or any combination of the two, however, these devices operate quite differently. Bars function to reduce roll by increasing weight transfer, while springs resist roll in accordance with their effective wheel rates without an additional weight transfer penalty. That latter part is what's so often missed by many a well meaning chassis tuner.
Thing is, tires don't gain traction in a linear relationship with an increasing load, rather on a curve of diminishing returns. Let's look at a hypothetical (but representative) scenario...
For simplicity's sake, say we have a set of tires on an axle carrying 2,000 lbs. which are each capable of 1.0 G lateral acceleration when carrying 1,000 lbs. load. If our vehicle experiences 250 lbs. of weight transfer in a corner, we now have 750 lbs. on the inner tire and 1,250 lbs. on the outer. Sure, we still have a total of 2,000 lbs. But, although the outer might be capable of 1.1 G, the inner tire may only be capable of 0.8 G, reducing the net available grip on the axle in question to 0.95 G, or a loss of 0.05 G. Problem is, we're not gaining G on the outer tire as quickly as we're loosing it on the inner, and the problem only gets worse as weight transfer increases. So, for however much total anti-roll is needed to keep our tires nice and square to the road, the higher percentage of that total is provided by bar, the less overall grip will be available.
Of course, how smooth is the surface on which we're operating ultimately limits how much spring is practical before keeping our tires on the ground becomes a problem of the first order (as well as looking after the well being of our backsides), forcing us to run less spring and more bar in order to provide sufficient anti-roll. But, IMCO that this compromise is frequently necessitated when navigating our way thru the vast grey area between billiard tables and washboards shouldn't be misinterpreted into the general notion that soft springs and big bars are always the best way to go. HTH
.
Thing is, tires don't gain traction in a linear relationship with an increasing load, rather on a curve of diminishing returns. Let's look at a hypothetical (but representative) scenario...
For simplicity's sake, say we have a set of tires on an axle carrying 2,000 lbs. which are each capable of 1.0 G lateral acceleration when carrying 1,000 lbs. load. If our vehicle experiences 250 lbs. of weight transfer in a corner, we now have 750 lbs. on the inner tire and 1,250 lbs. on the outer. Sure, we still have a total of 2,000 lbs. But, although the outer might be capable of 1.1 G, the inner tire may only be capable of 0.8 G, reducing the net available grip on the axle in question to 0.95 G, or a loss of 0.05 G. Problem is, we're not gaining G on the outer tire as quickly as we're loosing it on the inner, and the problem only gets worse as weight transfer increases. So, for however much total anti-roll is needed to keep our tires nice and square to the road, the higher percentage of that total is provided by bar, the less overall grip will be available.
Of course, how smooth is the surface on which we're operating ultimately limits how much spring is practical before keeping our tires on the ground becomes a problem of the first order (as well as looking after the well being of our backsides), forcing us to run less spring and more bar in order to provide sufficient anti-roll. But, IMCO that this compromise is frequently necessitated when navigating our way thru the vast grey area between billiard tables and washboards shouldn't be misinterpreted into the general notion that soft springs and big bars are always the best way to go. HTH
.
Last edited by TheSkunkWorks; 01-31-2017 at 07:13 PM. Reason: clarification
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01-10-2017, 11:45 PM
#22
Drifting
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Well I was a bit slow to come back to reply, but yes, you got your answer! 69427 and TheSkunkWorks have it covered.
Last edited by Metalhead140; 01-10-2017 at 11:48 PM.
01-11-2017, 12:31 AM
#23
The primary reason we wish to limit roll is to help best maintain the integrity of the contact patches on all four tires by avoiding excessive dynamic alignment changes. This can be achieved with bar or spring, or any combination of the two, however, these devices operate quite differently. Bars function to reduce roll by increasing weight transfer, while springs resist roll in accordance with their effective wheel rates without an additional weight transfer penalty. That latter part is what's so often missed by many a well meaning chassis tuner.
Thing is, tires don't gain traction in a linear relationship with an increasing load, rather on a curve of diminishing returns. Let's look at a hypothetical (but representative) scenario...
For simplicity's sake, say we have a set of tires on an axle carrying 2,000 lbs. which are each capable of 1.0 G lateral acceleration when carrying 1,000 lbs. load. If our vehicle experiences 250 lbs. of weight transfer in a corner, we now have 750 lbs. on the inner tire and 1,250 lbs. on the outer. Sure, we still have a total of 2,000 lbs. But, while the inner tire may still be capable of 0.8 G our outer might only be capable of 1.1 G, reducing the available grip on the axle in question to only 0.95 G, or a net loss of 0.05 G. Problem is, we're not gaining G on the outer tire as quickly as we're loosing it on the inner, and the problem only gets worse as weight transfer increases. So, for however much total anti-roll is needed to keep our tires nice and square to the road, the higher percentage of that total is provided by bar, the less overall grip will be available.
Of course, how smooth is the surface on which we're operating ultimately limits how much spring is practical before keeping our tires on the ground becomes a problem of the first order (as well as looking after the well being of our backsides), forcing us to run less spring and more bar in order to provide sufficient anti-roll. But, IMCO that this compromise is frequently necessitated when navigating our way thru the vast grey area between billiard tables and washboards shouldn't be misinterpreted into the general notion that soft springs and big bars are always the best way to go. HTH
.
Thing is, tires don't gain traction in a linear relationship with an increasing load, rather on a curve of diminishing returns. Let's look at a hypothetical (but representative) scenario...
For simplicity's sake, say we have a set of tires on an axle carrying 2,000 lbs. which are each capable of 1.0 G lateral acceleration when carrying 1,000 lbs. load. If our vehicle experiences 250 lbs. of weight transfer in a corner, we now have 750 lbs. on the inner tire and 1,250 lbs. on the outer. Sure, we still have a total of 2,000 lbs. But, while the inner tire may still be capable of 0.8 G our outer might only be capable of 1.1 G, reducing the available grip on the axle in question to only 0.95 G, or a net loss of 0.05 G. Problem is, we're not gaining G on the outer tire as quickly as we're loosing it on the inner, and the problem only gets worse as weight transfer increases. So, for however much total anti-roll is needed to keep our tires nice and square to the road, the higher percentage of that total is provided by bar, the less overall grip will be available.
Of course, how smooth is the surface on which we're operating ultimately limits how much spring is practical before keeping our tires on the ground becomes a problem of the first order (as well as looking after the well being of our backsides), forcing us to run less spring and more bar in order to provide sufficient anti-roll. But, IMCO that this compromise is frequently necessitated when navigating our way thru the vast grey area between billiard tables and washboards shouldn't be misinterpreted into the general notion that soft springs and big bars are always the best way to go. HTH
.
01-11-2017, 01:58 AM
#24
Drifting
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It's also why drag cars are setup to transfer weight to the rear tyres - increased grip. In that instance the load is constant with the weight of the car vs acceleration, but as the rear wheels do all the work, increasing the weight on the rear tyres increases their traction. With the transfer of weight from front to rear, at the same time you obviously have drastically reduced front end grip.
A sway bar limits roll by transferring additional weight to the outside wheel. This decreases traction at the end of the car that the sway bar is acting on, but increases it at the opposite end, which is maintaining a more equal load across inside and outside tyres due to reduced bodyroll. Stiffer springs can achieve the same benefit without as substantial a reduction in grip as it's not trying to lift the inside wheel and transfer that weight to the outside wheel, it's just reducing wheel travel at the outside wheel. But they have an obvious downside over rougher surfaces...
Last edited by Metalhead140; 01-11-2017 at 01:58 AM.
01-11-2017, 12:32 PM
#26
Le Mans Master
Bottom Line: There is nothing to be gained, other than to intentionally compromise one end of the car when the other cannot be improved, by running more total anti-roll (provided by whatever combination of spring and/or bar) on any given axle than is absolutely necessary. Hope that helps.
.
Last edited by TheSkunkWorks; 01-11-2017 at 12:34 PM.
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Metalhead140 (01-11-2017)
01-11-2017, 05:10 PM
#27
Racer
Hi Adam, you got all the best C3 suspension info all in one thread! Took me weeks to find all this out.
I have nothing to add except regarding your front springs, some will probably say its OK to cut the 550 even further. I didn't do that though. I've taken one full coil off of my VB&P 460 springs which mathematically makes them roughly 525ish? My fender lip is 3/4" above the 245/45/18 tire....perfect.
I doubt I'll ever want a rear sway bar either. Have yet to find my limit on those traffic circles just south of Woodinville on 202.
Steve
I have nothing to add except regarding your front springs, some will probably say its OK to cut the 550 even further. I didn't do that though. I've taken one full coil off of my VB&P 460 springs which mathematically makes them roughly 525ish? My fender lip is 3/4" above the 245/45/18 tire....perfect.
I doubt I'll ever want a rear sway bar either. Have yet to find my limit on those traffic circles just south of Woodinville on 202.
Steve
01-11-2017, 05:26 PM
#28
Melting Slicks
Thread Starter
Hi Adam, you got all the best C3 suspension info all in one thread! Took me weeks to find all this out.
I have nothing to add except regarding your front springs, some will probably say its OK to cut the 550 even further. I didn't do that though. I've taken one full coil off of my VB&P 460 springs which mathematically makes them roughly 525ish? My fender lip is 3/4" above the 245/45/18 tire....perfect.
I doubt I'll ever want a rear sway bar either. Have yet to find my limit on those traffic circles just south of Woodinville on 202.
Steve
I have nothing to add except regarding your front springs, some will probably say its OK to cut the 550 even further. I didn't do that though. I've taken one full coil off of my VB&P 460 springs which mathematically makes them roughly 525ish? My fender lip is 3/4" above the 245/45/18 tire....perfect.
I doubt I'll ever want a rear sway bar either. Have yet to find my limit on those traffic circles just south of Woodinville on 202.
Steve
I'm not going to remove my stock gymkhana sway bars, but after this thread, I won't be quick to upgrade them, either.
Adam
01-11-2017, 08:15 PM
#29
01-12-2017, 01:24 AM
#30
Le Mans Master
I wouldn't hold my breath waiting to crack that particular nut (no flames intended, but good luck with that one) before testing alternative setups. Despite having had the privilege of working with some fairly sophisticated data acquisition, and spent time along side a number of astute tire and race engineers over the years, more often than not interpreting tire temps, evaluating driver feedback, and checking with the stopwatch have proven among the best tools from which to get a decent read on whether the tires happen to like or dislike any particular change. One thing is for sure; getting stuck on any one setup (or preconceived notion) is a good recipe for leaving performance on the table. YMMV
02-13-2018, 12:44 PM
#31
Strut spacer
I started at the same spot as you, '79 with factory gymkhana suspension. I wanted to dramatically improve the handling without spending too many $. I rebuilt everything last year and I'm very happy with how it turned out. I intend to do some hillclimbs and track days (have done lots in the past, but not yet in the Vette). My background is mostly with modified light, good handling, unassisted rack and pinion British sports cars, so perhaps my tolerance for ride is higher than most? Regardless, I think my Vette, though fairly stiff, rides very well.
- Energy Suspension poly bushes throughout
- Moog ball joints, idler arm, tie rods etc
- Bilstein Sport shocks front and rear
- Global West tubular upper arms (for improved caster, and camber curve)
- 1 coil removed from front factory gymkhana springs
- Borgeson steering
- Shortened factory gymkhana rear leaf (for clearance for my 17"x9.5" wheels) with 8" bolts to lower ride height
- Relocated handbrake cable on top of trailing arms (for clearance for my 17"x9.5" wheels)
- Rebent rear sway bar arms (for clearance for my 17"x9.5" wheels)
- 1/2" Spacer (and longer bolts) fitted between diff centre and strut to bracket to improve rear camber curve.
- SpeedDirect spreader bar
- Ridetech steering box brace
- Solid engine mounts
- Aggressive suspension and steering alignment
- 17x9.5 wheels, 255/50r17 Nitto Invos
I think the car drives great. I wouldn't suggest going to a larger bar on the rear straight away, especially given your planned hp increases, you may find it unnecessary. I haven't had it on the track yet to see if I want a bit more stiffness in the rear on a fast sweeping corner, but it certainly doesn't feel understeery on the street. My next upgrades would be a glass rear spring (as much for weight as anything) and I will fit heim jointed strut rods when the bushes wear out (budget was getting thin at that point and I had the complete car Energy Suspension bush kit), and I also want to do the solid diff mount and relocation. But I really don't see any need to upgrade at this point, I'm very happy with it. I may fit a lower pressure valve to the steering pump to reduce assistance as I'm used to driving vehicles with unassisted steering, but it's certainly not necessary.
Edit: I strongly suggest reading the Vette Improvement Program articles. You can find them here: http://corvette.wikia.com/wiki/Suspension
- Energy Suspension poly bushes throughout
- Moog ball joints, idler arm, tie rods etc
- Bilstein Sport shocks front and rear
- Global West tubular upper arms (for improved caster, and camber curve)
- 1 coil removed from front factory gymkhana springs
- Borgeson steering
- Shortened factory gymkhana rear leaf (for clearance for my 17"x9.5" wheels) with 8" bolts to lower ride height
- Relocated handbrake cable on top of trailing arms (for clearance for my 17"x9.5" wheels)
- Rebent rear sway bar arms (for clearance for my 17"x9.5" wheels)
- 1/2" Spacer (and longer bolts) fitted between diff centre and strut to bracket to improve rear camber curve.
- SpeedDirect spreader bar
- Ridetech steering box brace
- Solid engine mounts
- Aggressive suspension and steering alignment
- 17x9.5 wheels, 255/50r17 Nitto Invos
I think the car drives great. I wouldn't suggest going to a larger bar on the rear straight away, especially given your planned hp increases, you may find it unnecessary. I haven't had it on the track yet to see if I want a bit more stiffness in the rear on a fast sweeping corner, but it certainly doesn't feel understeery on the street. My next upgrades would be a glass rear spring (as much for weight as anything) and I will fit heim jointed strut rods when the bushes wear out (budget was getting thin at that point and I had the complete car Energy Suspension bush kit), and I also want to do the solid diff mount and relocation. But I really don't see any need to upgrade at this point, I'm very happy with it. I may fit a lower pressure valve to the steering pump to reduce assistance as I'm used to driving vehicles with unassisted steering, but it's certainly not necessary.
Edit: I strongly suggest reading the Vette Improvement Program articles. You can find them here: http://corvette.wikia.com/wiki/Suspension
For strut bracket to differential mounting?
02-13-2018, 01:12 PM
#32
Safety Car
Member Since: May 2004
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02-13-2018, 01:21 PM
#33
Advanced
I have been working on my front suspension lately. I have done a full energy suspension poly conversion, with new ball joints as well. My car is also a factory gymkhana car so i left my factory sway bar an am replacing my frame mount and end link bushings with energy suspension polys. I put a new 550 lowering spring in with bilstein sport shocks. I could not be happier with the ride height, I have not tested it out yet because i am still working on it.
If you want to see how i did it i have a series of videos on you tube, here is a link to my playlist:
As far as rear suspension goes i will be installing a 360 spring and poly conversion as well. I agree with Shark Racer that the factory gymkhana rear sway bar is enough, The way i see it is that the mono leaf kind of acts as a stabilizer as well so you dont need a massive sway bar in the rear because then you will have no give and you wont know when to let off until its too late and you slide out.
If you want to see how i did it i have a series of videos on you tube, here is a link to my playlist:
As far as rear suspension goes i will be installing a 360 spring and poly conversion as well. I agree with Shark Racer that the factory gymkhana rear sway bar is enough, The way i see it is that the mono leaf kind of acts as a stabilizer as well so you dont need a massive sway bar in the rear because then you will have no give and you wont know when to let off until its too late and you slide out.
Last edited by samuel082799; 02-13-2018 at 01:21 PM.
02-13-2018, 08:10 PM
#34
Le Mans Master
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Posted on here back in '14 and I was told not to use poly bushings in my strut rods.
Quote:
Originally Posted by F4Gary View Post
I need to replace the bushings in my strut rods and was thinking of using poly bushings. I'm now rethinking this.
Reply:
"this is one of the worst places to use poly. use rubber or go with heim joints."
Is this still true?
Quote:
Originally Posted by F4Gary View Post
I need to replace the bushings in my strut rods and was thinking of using poly bushings. I'm now rethinking this.
Reply:
"this is one of the worst places to use poly. use rubber or go with heim joints."
Is this still true?
Last edited by F4Gary; 02-13-2018 at 08:10 PM.
02-13-2018, 08:16 PM
#35
Team Owner
Late to the thread....oh well, I think it depends on the type of driving to be done......full out competition...leave me outta the discussion....spirited street driving...FUN without going nutz.....IMO the first thing is wheels/tires....and then PRICES....so to do a C4 wheels 17" conversion with VBP 2.5" thick adapters....keep same wheel center line but with 1.5" increased rim width and 2" diameter.....better rubber is the foundation...
then for more RIDE I noticed not so much with handling....a VBP rear plastic spring.... 360# is what I have....over the years I spent the BUX and went Billy Stein sports on all 4 corners....nice ride improvement....
my rear sway bar is a bit less than 1/2 diameter....my front is less than an inch.....urethane bushings on bottom....rubber up top, due to ease of parts when needed over the last 22 years.....
now here is the trick.....RACK STEERING I installed myself winter 01-02......2.7 turns lock/lock not 3.7........also Hydroboost brakes....
but of course you have to know, the entire car is totally updated and modified to my specs/needs/seating/ steering column is a small diameter from a late shark..TT.......dropped the seat a couple inches in rear....cut firewall and moved forward about 3" and reglassed it pushing pedals forward the same amount....keeps my knees off the wheel.....the smaller wheel is what's important, don't feel like you driving a bus....
pix at bottom of post....
then for more RIDE I noticed not so much with handling....a VBP rear plastic spring.... 360# is what I have....over the years I spent the BUX and went Billy Stein sports on all 4 corners....nice ride improvement....
my rear sway bar is a bit less than 1/2 diameter....my front is less than an inch.....urethane bushings on bottom....rubber up top, due to ease of parts when needed over the last 22 years.....
now here is the trick.....RACK STEERING I installed myself winter 01-02......2.7 turns lock/lock not 3.7........also Hydroboost brakes....
but of course you have to know, the entire car is totally updated and modified to my specs/needs/seating/ steering column is a small diameter from a late shark..TT.......dropped the seat a couple inches in rear....cut firewall and moved forward about 3" and reglassed it pushing pedals forward the same amount....keeps my knees off the wheel.....the smaller wheel is what's important, don't feel like you driving a bus....
pix at bottom of post....
02-13-2018, 08:20 PM
#36
Advanced
Posted on here back in '14 and I was told not to use poly bushings in my strut rods.
Quote:
Originally Posted by F4Gary View Post
I need to replace the bushings in my strut rods and was thinking of using poly bushings. I'm now rethinking this.
Reply:
"this is one of the worst places to use poly. use rubber or go with heim joints."
Is this still true?
Quote:
Originally Posted by F4Gary View Post
I need to replace the bushings in my strut rods and was thinking of using poly bushings. I'm now rethinking this.
Reply:
"this is one of the worst places to use poly. use rubber or go with heim joints."
Is this still true?
02-14-2018, 06:05 AM
#37
Drifting
Member Since: Aug 2015
Location: NSW, Australia
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Missed this thread somehow when it first came around. With regard to this spacer for camber gain: is this just a seat-of-the-pants SWAG, or did you actually calculate or somehow measure the camber change, Metalhead? If so, we probably all would be interested in seeing the results. Thanks
I had been considering removing it, as trackside photos show my outside rear going a little positive under heavy cornering, but after discussions with some race suspension experts, they believe that it is best for me to keep the reduced camber curve and increase my static neg camber - I run -1.5 on the front, but only around -0.5 on the rear at present.
Edit: Just re-read the quoted post, I have done a lot of competitive events since then and the car is doing very well. I regularly beat up on much newer machinery, including the turbo awd brigade, even on tracks you would think would be much too tight for a big old Vette. Some in-car video from the weekend here if you want to see how it works:
Last edited by Metalhead140; 02-14-2018 at 06:45 AM.
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ignatz (02-14-2018)
02-14-2018, 12:23 PM
#38
Racer
Posted on here back in '14 and I was told not to use poly bushings in my strut rods.
Quote:
Originally Posted by F4Gary View Post
I need to replace the bushings in my strut rods and was thinking of using poly bushings. I'm now rethinking this.
Reply:
"this is one of the worst places to use poly. use rubber or go with heim joints."
Is this still true?
Quote:
Originally Posted by F4Gary View Post
I need to replace the bushings in my strut rods and was thinking of using poly bushings. I'm now rethinking this.
Reply:
"this is one of the worst places to use poly. use rubber or go with heim joints."
Is this still true?
Poly bushings work well for loads that have just a push/pull or just a rotational force on them. They don't work well when you add twisting
or have movement in multiple planes like the strut rods or rear control arms do. For these, it's best to use a more compliant rubber bushing or step up to a solid joint such as heims for the strut rods and johnny joints for the trailing arms.
02-14-2018, 03:59 PM
#39
Team Owner
Naturally neutral balance and the level of Mods is dependent on usage and speeds! The levels being talked about here, will not make it a winning car on suspension alone!
The Herb Adams bracket is just cut square tubing and the size doesn't need the spacer as that is basically accounted for in his crude design! Basically you need to figure out yourself as to where you set your rear suspension as related to control arm angles in relation to halfshafts and setting spring end adjustments or coilovers! I would never have poly in the camber control rods!
So far the thread seems to be chasing a good medium formula for decent handling! Something that compliments max performance street tires!
You can go crazy with this, as an example I have about 6 separate sets of rear sway bar bushing mounting holes drilled to move them to lessen or increase leverage of the bar itself! Thought that one up on my own! And I also have adjustable sway bar struts to tune as I adjust up or down the coilovers!
The Herb Adams bracket is just cut square tubing and the size doesn't need the spacer as that is basically accounted for in his crude design! Basically you need to figure out yourself as to where you set your rear suspension as related to control arm angles in relation to halfshafts and setting spring end adjustments or coilovers! I would never have poly in the camber control rods!
So far the thread seems to be chasing a good medium formula for decent handling! Something that compliments max performance street tires!
You can go crazy with this, as an example I have about 6 separate sets of rear sway bar bushing mounting holes drilled to move them to lessen or increase leverage of the bar itself! Thought that one up on my own! And I also have adjustable sway bar struts to tune as I adjust up or down the coilovers!
Last edited by TCracingCA; 02-14-2018 at 04:30 PM.
02-14-2018, 10:13 PM
#40
Team Owner
Made it myself. All you need is an appropriate thickness piece of steel or aluminium plate, cut it to size and drill some holes in it.
I haven't measured it... ...yet. It's pretty high on my to-do list though as I'm making plans to slip the half shaft and add an upper link to control camber to take the load off the half shaft. I plan to change the geometry at the same time to allow a lower ride height with the best toe curve available from the trailing arm at that lower ride height. The spacer is suggested in the Vette Improvement Program docs (Greenwood) and I think also by Herb. I believe it results in about the same geometry as the VB&P Smart Strut bracket.
I had been considering removing it, as trackside photos show my outside rear going a little positive under heavy cornering, but after discussions with some race suspension experts, they believe that it is best for me to keep the reduced camber curve and increase my static neg camber - I run -1.5 on the front, but only around -0.5 on the rear at present.
Edit: Just re-read the quoted post, I have done a lot of competitive events since then and the car is doing very well. I regularly beat up on much newer machinery, including the turbo awd brigade, even on tracks you would think would be much too tight for a big old Vette. Some in-car video from the weekend here if you want to see how it works:
I haven't measured it... ...yet. It's pretty high on my to-do list though as I'm making plans to slip the half shaft and add an upper link to control camber to take the load off the half shaft. I plan to change the geometry at the same time to allow a lower ride height with the best toe curve available from the trailing arm at that lower ride height. The spacer is suggested in the Vette Improvement Program docs (Greenwood) and I think also by Herb. I believe it results in about the same geometry as the VB&P Smart Strut bracket.
I had been considering removing it, as trackside photos show my outside rear going a little positive under heavy cornering, but after discussions with some race suspension experts, they believe that it is best for me to keep the reduced camber curve and increase my static neg camber - I run -1.5 on the front, but only around -0.5 on the rear at present.
Edit: Just re-read the quoted post, I have done a lot of competitive events since then and the car is doing very well. I regularly beat up on much newer machinery, including the turbo awd brigade, even on tracks you would think would be much too tight for a big old Vette. Some in-car video from the weekend here if you want to see how it works:
About 1.5 negative would be about all I would ever run on the street! And that won't suffice to make you one of the top runners for autocross or track. 1.5 camber, I would be pushing out the castor on the front end, or it will be darty as hell!
So someone tell me, what is the movement range on those fancy dancy so called Smart Struts?????
Last edited by TCracingCA; 02-14-2018 at 10:14 PM.