idk weather not to put some money into this car its a convertible and im not the biggest fan of convertibles. with the car be able to handle 500rwhp with ur average full length subframes? and wheelhop is terrible in the vert any suggestions or tips? on this or should i sell for a coupe? its a 99 thanks in advance.
cobra help
- Thread starter 1996dohcsvt
- Start date
Sub-frame will do the most good in deflection but not a lot under torsion loads which is what you need with a high hp engine. The floor pan on a vert is pretty much all you have connecting the front half with the back half. The roof on a coup goes a long way to brace the chassis. In a bad accident I've seen Mustang verts get torn in half. I Personally I would not go wild with a vert but I'm sure some people would disagree. A coup "all-the-way" for me on a performance car.
If you decide to go forward get some beefy jacking rails like Global West or Hans Racecraft. A decent roll bar is good if you go on the flip side but they tend to eat up back seat room.
If you decide to go forward get some beefy jacking rails like Global West or Hans Racecraft. A decent roll bar is good if you go on the flip side but they tend to eat up back seat room.
:nono:
The SN95 doesn't have a frame per say. It employs a uni-body chassis (tab welded sheet metal construction). They tend to sheer off at the front clip depending on the impact angle but I would worry more about an A-piller collapse in a rollover :uh oh:
well that pretty disappointing to hear its gonna be used for street with the occasional track use. so u think i should go the coupe route?
I THINK brebar is joking. There are plenty of guys with verts making more then 500hp. Make sure you stiffen everything up with SFC's and jacking rails. I think you need some kind of roll bar for anything faster then a 13.99 in a vert.
What's it like to be that guy?
lol so should i keep it or go for a coupe help please! lol thanks.
Wouldn't want to know. Mustangs do hold up pretty well in accidents but the verts as you know don’t fair quite as well.
Here are pics of Boosted vert after it was sandwiched by a truck and got up ended in the process.
Here is the thread, very scary :uh oh:
http://www.svtperformance.com/forums/terminator-talk-229/597959-r-i-p-my-sweet-cobra.html
About 4 years ago some kid in an SN95 vert was beyond speeding down the Colorado Blvd. here in Pasadena (the route the Rose Bowl takes) and lost control and slammed into a brick building which tore the car in half. The carnage was unreal and the only thing that made it recognizable that it was a car was the seat lying in the middle of the road. The officer at the scene said it was a Mustang convertible and that the driver was whisked away in an ambulance and was still alive but barely.
Maybe it's just me but I get very nervous in a fire breathing car with no roof structure over my head. Verts are nice cars to ride around in but if I bought a Mustang vert it would have a V6 and the slushbox option. A coup is certainly no guarantee you will walk away after an accident but having an A, B and C piller with all that metal overhead increases my comfort level.
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yah i c im just worried about the structure of the car for the added extra horses.
Yep, no 'frame' has layers, pieced together to crumple upon impact at the weld points. I believe 4 dif layers. In regards to the picture, I'm sure it would have been very similar damage with exception to top portion of the car. Its no secret with no roof you are more likely to have serious bodily injury, we know this.
In regards to you ripping your car apart from sheer force using 500 hp, what thought process could bring you to that conclusion lmao?
In regards to you ripping your car apart from sheer force using 500 hp, what thought process could bring you to that conclusion lmao?
no my original intent was i want my car to have 5-600rwhp when finished and i was wondering can a vert structualy handle this without twisting it the unibody launched hard on slicks. i dont wanna put in a cage i think there ugly imo so i wanna just go as far as flsfc and the wheel hop in this convertible is almost unbearable.
Turn traction control off to assist wheel hop? Lol. You can also do an SRA swap. But to put down 500+ HP, your going to need to dump some money into suspension and braking more than just SFC's.
Thats alot of ponies, and with the increased torque, if you don't have any way to transfer it to the pavement too bad so sad. Im sure you probably already have plans on that.
No, 500 hp+ will not rip the ****in body apart. Thats just dumb. Sorry.
Thats alot of ponies, and with the increased torque, if you don't have any way to transfer it to the pavement too bad so sad. Im sure you probably already have plans on that.
No, 500 hp+ will not rip the ****in body apart. Thats just dumb. Sorry.
Depends what you mean by "structurally handle". Even the coup chassis with slicks and gears will twist and fatigue over time. Drag racing absolutely beats the hell out of the metal especially when you consider all the torque multiplication that takes place through the driveline.
This is not something hard to figure out. There are scores of verts making big horsepower and most of their owners know the SN95 chassis rigidity is less than ideal with some taking steps to address its shortcomings. The problem is as you pointed out is that you end up with a car interior that reminiscent of a jungle gym. Putting a roll cage in a car can actually make it more dangerous to the occupants if they do not wear a helmet. The DOT would never allow a car with hard metal tubing snaking every which way inside the passenger compartment and risk head injury to the occupants. The old fox chassis were even worse with lots of metal punched out in the structure to lighten it. The fact is this car was never design to handle the hp the engines they started to equip them with.
If you plan on drag racing the car, over time chassis will loosen up and will rattle and creak incessantly. Being a mechanical engineer having done extensive stiffening to my 04 I know every piece of sheet metal in this car and let me tell you it can get scary. But this car is no different than most all other mass produced automobiles but then again not many can make the power the Ford mod motor can with very little effort.
If chassis rigidity is important to you more than having a convertible then get a coup and vice versa. Better yet get an S197 which is about 50% stiffer then the SN95 but there is a weight penalty to be paid. Almost everything in this hobby is a compromise and there is no way getting around it. Pick your poison.
BTW: Use the "search" function. Much knowledge to be gained doing so.
:burnout:
cobraracer46
Banned
A SN95 mustang convertible can handle high HP and multiple launches if it is properly stiffened.
Here I am installing the Griggs frame kit on my Vortech T trim powered 01 Cobra. The car already had a set global west lower subframes. The Griggs frame set up was welded to the Global West lowers in the mid point of the car. Also installed were bulk head stiffeners below the B- pillar area area under the rear seats. Griggs claims that chassis rigidity increases 1500% with their frame kit. This set up is an absolute must for high power hard driven SN-95 vert mustangs.
My 01 Cobra feels tighter than a hard top with this set up and there no squeaks and rattles.
Another critical area to strengthen on SN-95 verts is the upper B-piller area and The Griggs racing SN-95 convertible roll bar WELDS in to the critical B-piller and rear bulk heads. Worthless SN-95 convertible roll bars such as the Autopower has a main hoop that BOLTS in to the paper thin floor pan and this does not strengthen the car and worse yet, it can and has punched right through the floor pan on one open track mustang that I know of.
Here is the griggs racing roll bar that I welded in my 01 vert and it noticeably tightened the car up and to me, it looks good.
With a stout set of subframes such as the Griggs frame kit that includes upper, lower subframes, plus bulk head stiffeners and a proper roll bar, the SN95 convertible chassis can take the abuse! Go with the vert and don't look back!
Here I am installing the Griggs frame kit on my Vortech T trim powered 01 Cobra. The car already had a set global west lower subframes. The Griggs frame set up was welded to the Global West lowers in the mid point of the car. Also installed were bulk head stiffeners below the B- pillar area area under the rear seats. Griggs claims that chassis rigidity increases 1500% with their frame kit. This set up is an absolute must for high power hard driven SN-95 vert mustangs.
My 01 Cobra feels tighter than a hard top with this set up and there no squeaks and rattles.
Another critical area to strengthen on SN-95 verts is the upper B-piller area and The Griggs racing SN-95 convertible roll bar WELDS in to the critical B-piller and rear bulk heads. Worthless SN-95 convertible roll bars such as the Autopower has a main hoop that BOLTS in to the paper thin floor pan and this does not strengthen the car and worse yet, it can and has punched right through the floor pan on one open track mustang that I know of.
Here is the griggs racing roll bar that I welded in my 01 vert and it noticeably tightened the car up and to me, it looks good.
With a stout set of subframes such as the Griggs frame kit that includes upper, lower subframes, plus bulk head stiffeners and a proper roll bar, the SN95 convertible chassis can take the abuse! Go with the vert and don't look back!
Now this guy took prudent steps to address the shortcoming of a convertible (wouldn't hurt on a coup either sans the rollbar). A set of beefy jacking rails would result in the same amount of stiffness and it eliminates the hump of the rectangular tubing from running along the floor keeping it flat but it's all good.
One thing to consider is there is still no reinforcement on the upper firewall without an upper brace leading to the A-piller or upper firewall and all the stress is still will be transfered to the floorboards. The roof structure boxes then mid-section of the chassis. Reinforcing the floorboard certainly will do much to stiffen the chassis but will be limited to a flat horizontal plane and won't cope with tortional loads like an upper brace or a roof. A convertible will never match the stiffness of a coup without a full rollcage running along the upper portion of the top down to the firewall but that kinda defeats the purpose of having a converible in the first place.
Also keep in mind running sub-frame connectors and a rollbar does not address the shortcomings if the front clip or backhalf of the chassis. Make the mid-section of the chassis super stiff will only make the structure at either end bare the brunt of the engine torque and it will flex more then if the bending forces were distributed along the entire length of the chassis. Run coilovers and the situation gets even worse as they are not designed to carry the weight of the car. But to address this properly is not practical and is something we all have to live with.
What your trying to do is limit movement of the chassis. When metal flexes it stretches/compresses which will fatigue the metal everytime there is a load applied to it. All the stress tranferred carried from one panel to the next will be focussed on the spotwelds where the stresses will be highest then will propagate along the next panel until it reaches the next spotweld and so on. Think of the chassis as one big spring. Slam the clutch at 5000 rpm and 3000 ft lbs of torque (after multiplied thru the driveline) and it will resist twisting but then energy will be required to maintain the torsion stored in the spring (chassis) until you let off on the pedal when the energy stored in the chassis is suddenly released. When you stiffen the chassis more of that energy will be tranferred directly to the rear wheels which would actually show up on a dyno. With an engine making 500 ft lbs of torque 30 - 40 ft lbs may be absorbed (stored) by the chassis. Think of it as taking a 3" dia rubber rod and twisting it between both hands and holding it while your arms strain to fight the energy stored in the rubber then let go suddenly.........BOING!
Not trying to scare anyone but thses are inescapable facts that every car made has to deal with. The shock loads of hard launches with slicks and gears will impose the worst stresses on the chassis. A chassis with a full rollcage extending from the front shock tower all the rear shock towers and sub-frame connection points is the only real way to minimize chassis flex. But that makes it a race car and is not realistic for the street.
Always keep this in mind when considering which type of car you want and how you want to use it. If your going to drag race it then accept the fact the chassis will degrade quicker. Stiffening it will slow that process. Road racing type loads and soft starts will be kinder to the chassis and the car will remain solid for a longer period.
Just something to keep in mind.
Russ :beer:
jeeez im so confused my goal is 500 whp and a mainly street with the occasional strip probably on drag radials is all that griggs frame kit neccesary for what i have intended sorry to bug you guys.
I'm right at 500rwhp in my vert. HIGHLY recommend subframe connectors at least. It still flexes a little on launch but significantly better than it was. I run Eagle GS-D3's on the road and swap to MT Drag Radials for the strip.
Still love the car and nothing beats some top-down cruising AND solid power...
Good luck in whatever direction you end up going!
Still love the car and nothing beats some top-down cruising AND solid power...
Good luck in whatever direction you end up going!
No need to "Jones" over this.
Buy the car you "want", not something somebody else tells you. What I seem to be hearing is that car is a vert. You have concerns about the chassis rigidity and already have plans to address it. Your on the right path.
:rockon:
Buy the car you "want", not something somebody else tells you. What I seem to be hearing is that car is a vert. You have concerns about the chassis rigidity and already have plans to address it. Your on the right path.
:rockon:
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