The 951 UNDERbody....???
02-28-2004, 11:00 PM
#18
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Originally posted by Fishey
You guys forgot that the cabriolets are compleately panneled underbody
or atleast mine is I think I showed it to some of the local guys...
You guys forgot that the cabriolets are compleately panneled underbody
or atleast mine is I think I showed it to some of the local guys...
03-01-2004, 03:38 AM
#23
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Thanks for the input guys- Rich's shot doesn't show any of them though- except for the front spoiler...is that the "batwing"?
Where is the "fanny pan then" - that doesn't make sense...
Danno- the panels you mentioned- you were joking weren't you? I'm referring to add on panels that are there for air flow only that IF removed, would not be missed by someone who didn't know- the pics of the three together- are they the ONLY ones? How can one of them be called a "fanny pan"? Is there any benefit in trying to make something that would continue back slightly further & maybe even cover the exhaust section? The Modena would be about perfect- the C5 Vette did a great job...
Anyone got any pics of the Convertibles? Would those panels be anything one would want to use on a coupe? Would they add any weight really? I mean, if they're plastic, then it couldn't be much... IF they're reeally an EXTRA floor as someone else suggested, then, they might be a little too much weight for what they're worth- also, are they easy to remove, etc? I guess pics would be the best way to show them.... anyone?
Where is the "fanny pan then" - that doesn't make sense...
Danno- the panels you mentioned- you were joking weren't you? I'm referring to add on panels that are there for air flow only that IF removed, would not be missed by someone who didn't know- the pics of the three together- are they the ONLY ones? How can one of them be called a "fanny pan"? Is there any benefit in trying to make something that would continue back slightly further & maybe even cover the exhaust section? The Modena would be about perfect- the C5 Vette did a great job...
Anyone got any pics of the Convertibles? Would those panels be anything one would want to use on a coupe? Would they add any weight really? I mean, if they're plastic, then it couldn't be much... IF they're reeally an EXTRA floor as someone else suggested, then, they might be a little too much weight for what they're worth- also, are they easy to remove, etc? I guess pics would be the best way to show them.... anyone?
03-01-2004, 06:30 AM
#24
Race Director
"Modena? They come like that stock?"
Ferrari F355. Yup they come that way from the factory. Got that picture from the Ferrari site. The Testarossa was actually the 1st production Ferrari to shy away from obvious upper-body wings and use underbody trays to manage airflow. It actually had zero lift at 150mph and about 150lbs of downforce or something like that.
Rather than creating a net zero-lift by counteracting underbody lift with an upper-body wing to generate a counteracting downforce (you've doubled the drag), they minimize that first part so there's no need for the 2nd opposing one. But you can't do that just with a flat bottom, even though that's still better than a messy uncovered one. Part of the problem with a flat bottom is that you end up with an air-foil shape where the entire car's body is a wing that generates lift (remember the flying Mercedes and GT1?). You need to reduce pressure on the bottom by increasing its velocity underneath and reducing its pressure. That's done with the rear diffuser like this add-on one on the Ferrari F50-GT1:
Better to have one built into the bodywork itself to have the edges sealed:
"the panels you mentioned- you were joking weren't you? I'm referring to add on panels that are there for air flow only that IF removed, would not be missed by someone who didn't know- the pics of the three together- are they the ONLY ones?"
Well, all of the ones I mentioned are on the Turbo and not the NA. Except that the NA has a single aluminum pan where the Turbo has those two pieces (the ones I flipped in Eyal's picture). There's also two 1/2 width panels that run underneath the middle of the car. You can see them in the jacking-points picture above. They don't fit all the way across like on the Ferrari probably because of the heat from the exhaust.
The tranny area is really messy. I'm sure the rear valance helps clean up the air-flow leaving the car somewhat, but it'd be better not to chop it up in the first place.
Ferrari F355. Yup they come that way from the factory. Got that picture from the Ferrari site. The Testarossa was actually the 1st production Ferrari to shy away from obvious upper-body wings and use underbody trays to manage airflow. It actually had zero lift at 150mph and about 150lbs of downforce or something like that.
Rather than creating a net zero-lift by counteracting underbody lift with an upper-body wing to generate a counteracting downforce (you've doubled the drag), they minimize that first part so there's no need for the 2nd opposing one. But you can't do that just with a flat bottom, even though that's still better than a messy uncovered one. Part of the problem with a flat bottom is that you end up with an air-foil shape where the entire car's body is a wing that generates lift (remember the flying Mercedes and GT1?). You need to reduce pressure on the bottom by increasing its velocity underneath and reducing its pressure. That's done with the rear diffuser like this add-on one on the Ferrari F50-GT1:
Better to have one built into the bodywork itself to have the edges sealed:
"the panels you mentioned- you were joking weren't you? I'm referring to add on panels that are there for air flow only that IF removed, would not be missed by someone who didn't know- the pics of the three together- are they the ONLY ones?"
Well, all of the ones I mentioned are on the Turbo and not the NA. Except that the NA has a single aluminum pan where the Turbo has those two pieces (the ones I flipped in Eyal's picture). There's also two 1/2 width panels that run underneath the middle of the car. You can see them in the jacking-points picture above. They don't fit all the way across like on the Ferrari probably because of the heat from the exhaust.
The tranny area is really messy. I'm sure the rear valance helps clean up the air-flow leaving the car somewhat, but it'd be better not to chop it up in the first place.
03-01-2004, 07:54 AM
#25
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I had often thought about the lift thing- if you had a perfectly flat underbody, the air can underneath & lift the whole car up like a Nascar tumble or something...
Danno- do you remember the original VW 16v's? The GTi in the late 80's? The Scirocco first came out w/VW's 16v in 86- in 87 that's the only engine it got & in 88, as well, but that was it's last year- italso happened to be the only year the VW 16v Scirocco was made in white- really cool IMO- car had a .38Cx- the GTi got the 16v in 87 & kept it through 89- actually, for much longer, but, the 16v was toyed w/a bunch of times- those engines put out 123HP & 120TQ- they were really cool in a lot of ways- the GTi had a .36Cx- they went to a 2.0L (FROM the 1.8) eventually, but, most enthusiats liked the 2.0 bottom end w/the 1.8 head- they said it became a 1.9L, but, this never made sense- kind of like the 192HP VR6 Corrado- the 2.9L- people say the best thing to increase HP/TQ for a 178HP/177TQ VR6 2.8L Corrado (bang for the buck) is to get the pistons from the 2.9L & bring the 2.8L up to that disp- they say the cost of the pistons is it- ~$900 & you've got the instant HP/TQ- well, trell me this- how in the FU** can one put larger pistons w/out making larger bores? Is it me? ANYWAY- back in the day, there was a place that made a mod for the 16vGTi- it was some sort of underbody deal that SUPPOSEDLY added ~30HP & added all kinds of downforce- it also said that this downforce added traction, as well, & allowed the car to gain somewhere ~.05G worth of lateral acceleration. It was only a few hundred, & was probably a complete POS, but, I always remembered it- would have bought one had I not owned an Integra instead...
ALSO- DANNO- another question- a long time ago, we were talking about stiffer front springs, etc & the effect on braking- YOU had told me that the same amount of weight would be transferred to the front wheels whether I had soft OR stiff springs- this never made sense to me, but, I'll take your word for it- let's compare front engine to rear engine- say, a 50/50 vs a 40/60- wouldn't the 40/60 transfer LESS weight forward? OR, what I mean, even if it did transfer the same amount of weight (or percentage) wouldn't it STILL have less weight on the front wheels in the END, thereby having it's rear wheels contribute more to the overall decceleration attempt? ALSO- would stiffer front springs in our cars help braking distances at ALL? I mean, regardless of whether or not the SAME amount of weight is being transferred w/my 225lb springs vs when I had stock Turbo S (~175lb springs), the front end is diving LESS, w/out question- not TONS, but, I'd bet it's a full inch less under threshold braking- that's a GOOD bit- so, would my braking distances be slightly shorter b/c of this? Just curious- I REALLY want to get the braking distance of this car down a little bit- I need to test my new pads (Axxis MM's) but they really suck when they're cold- I've never been very impressed w/the braking ability of this car- my distances just aren't that good & I've done a few things over & above stock- I'll HAVE to check the Axxis MM's before I can be 100% sure, as of nw, but, I've also got stiffer springs at the same time, so, if I'm better off, I' not sure how much will be pads & how much springs, etc
Now, if only I could get my 951 to outhang my Integra... yes, I'm a little BITTER about that....
Danno- do you remember the original VW 16v's? The GTi in the late 80's? The Scirocco first came out w/VW's 16v in 86- in 87 that's the only engine it got & in 88, as well, but that was it's last year- italso happened to be the only year the VW 16v Scirocco was made in white- really cool IMO- car had a .38Cx- the GTi got the 16v in 87 & kept it through 89- actually, for much longer, but, the 16v was toyed w/a bunch of times- those engines put out 123HP & 120TQ- they were really cool in a lot of ways- the GTi had a .36Cx- they went to a 2.0L (FROM the 1.8) eventually, but, most enthusiats liked the 2.0 bottom end w/the 1.8 head- they said it became a 1.9L, but, this never made sense- kind of like the 192HP VR6 Corrado- the 2.9L- people say the best thing to increase HP/TQ for a 178HP/177TQ VR6 2.8L Corrado (bang for the buck) is to get the pistons from the 2.9L & bring the 2.8L up to that disp- they say the cost of the pistons is it- ~$900 & you've got the instant HP/TQ- well, trell me this- how in the FU** can one put larger pistons w/out making larger bores? Is it me? ANYWAY- back in the day, there was a place that made a mod for the 16vGTi- it was some sort of underbody deal that SUPPOSEDLY added ~30HP & added all kinds of downforce- it also said that this downforce added traction, as well, & allowed the car to gain somewhere ~.05G worth of lateral acceleration. It was only a few hundred, & was probably a complete POS, but, I always remembered it- would have bought one had I not owned an Integra instead...
ALSO- DANNO- another question- a long time ago, we were talking about stiffer front springs, etc & the effect on braking- YOU had told me that the same amount of weight would be transferred to the front wheels whether I had soft OR stiff springs- this never made sense to me, but, I'll take your word for it- let's compare front engine to rear engine- say, a 50/50 vs a 40/60- wouldn't the 40/60 transfer LESS weight forward? OR, what I mean, even if it did transfer the same amount of weight (or percentage) wouldn't it STILL have less weight on the front wheels in the END, thereby having it's rear wheels contribute more to the overall decceleration attempt? ALSO- would stiffer front springs in our cars help braking distances at ALL? I mean, regardless of whether or not the SAME amount of weight is being transferred w/my 225lb springs vs when I had stock Turbo S (~175lb springs), the front end is diving LESS, w/out question- not TONS, but, I'd bet it's a full inch less under threshold braking- that's a GOOD bit- so, would my braking distances be slightly shorter b/c of this? Just curious- I REALLY want to get the braking distance of this car down a little bit- I need to test my new pads (Axxis MM's) but they really suck when they're cold- I've never been very impressed w/the braking ability of this car- my distances just aren't that good & I've done a few things over & above stock- I'll HAVE to check the Axxis MM's before I can be 100% sure, as of nw, but, I've also got stiffer springs at the same time, so, if I'm better off, I' not sure how much will be pads & how much springs, etc
Now, if only I could get my 951 to outhang my Integra... yes, I'm a little BITTER about that....