hey...i recognize that car
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does the LS Splitter unbalance the handling?
- Thread starterpufferfish
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Down force is only part of the aero question drag is the other. The vented hood lowers drag while improving down force. Getting the air from under the car to meet the air from on top at the rear of the car is where a lot of drag is created getting those separate flows to meld back together smoothly decreases drag which allows you run more down force. Getting the air under the car to travel faster creates down force, letting air escape through the hood speeds the air up under the car as does a flat bottom.
Grant 302
basic and well known psychic
pufferfish said:
I would not install the LS splitter without something more than the base spoiler. At low speeds, the differences should be negligible. But at higher speeds, you will have more downforce at the front. And if you brake at higher speeds, the splitter will generate even more downforce as your front end dives. All of this happening while your car is already light in the rear from braking weight transfer...
And that's a good recipe for a tendency to snap oversteer at high speed, if you do not have some other mod to compensate which is speed dependent.
All just my opinion...I didn't read this anywhere.
- Thread starter
- #24
pufferfish
Supporting Vendor
well, i believe i have a much better understanding now. thanks guys! i was looking and the LS/CS rear pedestal wing is pretty reasonably priced and i can get it in time for the event...buuutttt....i thought about it and realized i may be inviting an opportunity to scrape the splitter off the car at the track i am going to. for those who have been to the summit point shenandoah circuit, that high banked carrousel is a rough one to get out of. low hanging parts can take a beating. maybe i will wait until i go to summit main or VIR.
And you don't just scrape the splitter off it usually takes the whole front valance and bumper cover.
Do you really think 1" or so will make a difference on the track? ;D I suspect if you're in for a low ride into the weeds the additional risk is small. If that concerned I think the real answer us to just stay with the stock splitter. I've done two 4-offs into the turf with my LS splitter and mine is 1" lower than stock. No issues so far.
captdistraction
GrumpyRacer
PeteInCT said:
For iracing, I usually have to change car setups for that track, there's a lot of "you don't want wheel input going over this" or "be ready to add input or else you're wearing a tirewall" all over the track.
I will throw my two cents in here.
The splitter adds down-force to the whole car, not just the front, because it sends a direct airflow under the car without turbulence at high speed. This creates a low pressure which pulls the entire car to the ground. That is why lowering the splitter makes a big difference, less air has to be "split" and sent underneath creating a better low pressure.
Saying that you could point the splitter down and that would add down force only on the front of the car or the opposite pointing it up and it would take away the down-force forcing it up. Neither of these is what a splitter is designed for.
The front of the car will create a high pressure as you move forward creating drag. I'm not sure that air in front of the car has anything to do with creating or taking away down force. Then the air then passes over the hood at a faster rate, again creating a low pressure which will want to lift the car up. This combined with a pressure build up (high) under the hood makes for even more lift. The air then passes the windshield, high pressure again, adding down-force only because of it location and over the roof where again it is fast and low. This is one reason NASCAR added the roof flaps to break up that wind so it does not create lift when spinning, it has worked very well.
So going back to the original question, yes the car will not be balanced like Ford wanted it. I am sure they did wind tunnel testing. I doubt it would be to the point of dangerous and unless you drive like Joe Foster I would guess most of us would not really under understand the difference. Still it would be best to have the splitter and spoiler working together just like adding the Tiger hood would be better with a taller spoiler even if it works fine for non-professionals like myself.
The splitter adds down-force to the whole car, not just the front, because it sends a direct airflow under the car without turbulence at high speed. This creates a low pressure which pulls the entire car to the ground. That is why lowering the splitter makes a big difference, less air has to be "split" and sent underneath creating a better low pressure.
Saying that you could point the splitter down and that would add down force only on the front of the car or the opposite pointing it up and it would take away the down-force forcing it up. Neither of these is what a splitter is designed for.
The front of the car will create a high pressure as you move forward creating drag. I'm not sure that air in front of the car has anything to do with creating or taking away down force. Then the air then passes over the hood at a faster rate, again creating a low pressure which will want to lift the car up. This combined with a pressure build up (high) under the hood makes for even more lift. The air then passes the windshield, high pressure again, adding down-force only because of it location and over the roof where again it is fast and low. This is one reason NASCAR added the roof flaps to break up that wind so it does not create lift when spinning, it has worked very well.
So going back to the original question, yes the car will not be balanced like Ford wanted it. I am sure they did wind tunnel testing. I doubt it would be to the point of dangerous and unless you drive like Joe Foster I would guess most of us would not really under understand the difference. Still it would be best to have the splitter and spoiler working together just like adding the Tiger hood would be better with a taller spoiler even if it works fine for non-professionals like myself.
I run the world challenge splitter and the Tiger hood with only the RTR blade spoiler on the rear deck set at a 35 degree angle. I have had no high speed instability that I can detect in high speed sweepers such as the Hog Pen at VIR, the Esses at VIR or the Downhill at Lime R ock which are entered at 65-80 mph and have the car g loaded at 100+ before exit. If anything I still have a touch of oversteer and sometimes (often?) breathe the throttle to get the rear to rotate. I also am still running staggered Corsas which bias the grip to the rear and don't brake away as abruptly as a DOT or race slick will. I welcome Gary's take on this topic based on his experiences.
Steve
PS Pete, Lime Rock on iRacing is very accurate for layout and feel. It's a good repetitive training tool to keep your rhythm and muscle memory sharp. They have the FR500 available, only has 325 hp but slightly more grip so lap times are pretty comparable. Since I like the feel of the real car I am actually slightly quicker in real life. The brake feel on my pedal setup while good for a sim rig just doesn't give the nuances of a real brake system. Try it out it's pretty cool. They have VIR, The Glen, Summit, Barber and Laguna with many more coming including Miller Motorsports for the Track Attack guys.
Steve
PS Pete, Lime Rock on iRacing is very accurate for layout and feel. It's a good repetitive training tool to keep your rhythm and muscle memory sharp. They have the FR500 available, only has 325 hp but slightly more grip so lap times are pretty comparable. Since I like the feel of the real car I am actually slightly quicker in real life. The brake feel on my pedal setup while good for a sim rig just doesn't give the nuances of a real brake system. Try it out it's pretty cool. They have VIR, The Glen, Summit, Barber and Laguna with many more coming including Miller Motorsports for the Track Attack guys.
Steve - Tnx for the info on iRacing. My PC's at home are fine for most work but they are not powerful enough to run that game, I've tried it multiple times. Once I upgrade i'll give it a try again.
As for the Corsa's, you may find that the Nitto NT-555R-II's, even though close to a slick, give much better rear end control (and warning) that the Corsa's. I am running 18" 285-35 up front and 305-35 in rear (as is Gary). They also have a LOT more grip. I've been getting about 24 to 26 heat cycles out of them as long as I watch my hot temps and rotate them L/R regularly (pay no attention to the tread direction, they seem to make no difference in dry conditions).
Side note: Who's battey relocation kit did you use? I'm thinking of pushing it to the rear.
As for the Corsa's, you may find that the Nitto NT-555R-II's, even though close to a slick, give much better rear end control (and warning) that the Corsa's. I am running 18" 285-35 up front and 305-35 in rear (as is Gary). They also have a LOT more grip. I've been getting about 24 to 26 heat cycles out of them as long as I watch my hot temps and rotate them L/R regularly (pay no attention to the tread direction, they seem to make no difference in dry conditions).
Side note: Who's battey relocation kit did you use? I'm thinking of pushing it to the rear.
Pete
http://www.jegs.com/i/Taylor/895/48203/10002/-1?parentProductId= Taylor Aluminum box and 1Gauge cables from Jegs;
Then I bought a set of lead battery post that thread into side post batteries and this is how I did it.
Mounted the battery box in the right rear corner of the trunk with the 3/8" rods per the instructions, easier if you pull the right muffler so you can see hoew much to trim the rods and also tighten the nuts and washers, use the lock washer and a dab of locktite. in the trunk I laid out where I wanted the ground cable to go on the frame and drilled a hole slightly smaller than the a 3/8" sheet metal hex screw and then ground a little paint and primer off where the cable will make contact and secured it. The positive cable I routed from the box into the cabin following the main body harness, I also encased the cable with the corragated plastic wire wrap that you can get at home depot of radio shack to guard aganst any chafing of the insulation, critical as this is a live cable at all times. Next I run it along the rocker and under the carpet and passenger kick panel. At the firewall there is a large body grommet that goes to the space under the battery location; this is behind the fender shield so take off right front wheel and remove the splash shield. Stop here and remove the stock battery and box etc, there should just be the 2 cables and sheet metal. Under the tray there is a hole that you will use to pass the positive cable from the firewall through to marry to the stock positive cable. Push the new cable through the body grommet by making a small x cut in the rubber, add the correct size grommet and then pass the cable up through the hole under the battery tray location into the engine bay. At the grommets I added some wraps of electrical tape to again protect the cable insulation from chafing and also used some black RTV to seal around the grommets. Measure how much cable you need to reach the cars main positive cable and cut to length. Crimp on an eye ring terminal end and wrap it with electrical tape up to the bottom of the ring. I then too another positive lead terminal and using the correct nut and lock washer bolted the post to the new cable, then take the stock positive cable and clamp it on to your new positive cable post. As you can see we have not cut 1 stock piece on the car except for drilling a few holes and widening the grommet hole at the firewall. Leaving the red boot intact I used 3M scotch wrap electrical insulating pads and wrapped the whole connection to minimize any chance of shorting and secured the cables with zip ties to various parts of the engine compartment so the don't come in contact with anything.
For the stock negative cable I drilled a hole smaller than the thread on another negative lead post and screwed the post to the sheet metal in the battery tray area up front. Finally I bought a 16" flat braided ground strap and bolted one end to the closest bellhousing bolt and the other end to a sheet metal ground in the tray area with a 3/8" hex sheet metal screw.
Back in the trunk I then ran the vent hose from the box to an existing grommet plug that vents in the frame rail and hooked up the positive and then the negative cables to the battery. I am running an Optima Red Top AGM battery so venting is not really required but its good to do anyway, with a stock wet acid battery its required so fumes don't build up in the car. Before starting check all areas for any evidence of smoke from melting insulation or shorting. It's not likely but you never know. Button up the the splash shield and tire and all trims you took off to route the cables. In over a year and a half I have run this setup with zero issues, it can be put back to stock in an hour and no one would ever know what was done. Start her up and enjoy the transfer of 35 pounds from the front to the rear!
Steve
http://www.jegs.com/i/Taylor/895/48203/10002/-1?parentProductId= Taylor Aluminum box and 1Gauge cables from Jegs;
Then I bought a set of lead battery post that thread into side post batteries and this is how I did it.
Mounted the battery box in the right rear corner of the trunk with the 3/8" rods per the instructions, easier if you pull the right muffler so you can see hoew much to trim the rods and also tighten the nuts and washers, use the lock washer and a dab of locktite. in the trunk I laid out where I wanted the ground cable to go on the frame and drilled a hole slightly smaller than the a 3/8" sheet metal hex screw and then ground a little paint and primer off where the cable will make contact and secured it. The positive cable I routed from the box into the cabin following the main body harness, I also encased the cable with the corragated plastic wire wrap that you can get at home depot of radio shack to guard aganst any chafing of the insulation, critical as this is a live cable at all times. Next I run it along the rocker and under the carpet and passenger kick panel. At the firewall there is a large body grommet that goes to the space under the battery location; this is behind the fender shield so take off right front wheel and remove the splash shield. Stop here and remove the stock battery and box etc, there should just be the 2 cables and sheet metal. Under the tray there is a hole that you will use to pass the positive cable from the firewall through to marry to the stock positive cable. Push the new cable through the body grommet by making a small x cut in the rubber, add the correct size grommet and then pass the cable up through the hole under the battery tray location into the engine bay. At the grommets I added some wraps of electrical tape to again protect the cable insulation from chafing and also used some black RTV to seal around the grommets. Measure how much cable you need to reach the cars main positive cable and cut to length. Crimp on an eye ring terminal end and wrap it with electrical tape up to the bottom of the ring. I then too another positive lead terminal and using the correct nut and lock washer bolted the post to the new cable, then take the stock positive cable and clamp it on to your new positive cable post. As you can see we have not cut 1 stock piece on the car except for drilling a few holes and widening the grommet hole at the firewall. Leaving the red boot intact I used 3M scotch wrap electrical insulating pads and wrapped the whole connection to minimize any chance of shorting and secured the cables with zip ties to various parts of the engine compartment so the don't come in contact with anything.
For the stock negative cable I drilled a hole smaller than the thread on another negative lead post and screwed the post to the sheet metal in the battery tray area up front. Finally I bought a 16" flat braided ground strap and bolted one end to the closest bellhousing bolt and the other end to a sheet metal ground in the tray area with a 3/8" hex sheet metal screw.
Back in the trunk I then ran the vent hose from the box to an existing grommet plug that vents in the frame rail and hooked up the positive and then the negative cables to the battery. I am running an Optima Red Top AGM battery so venting is not really required but its good to do anyway, with a stock wet acid battery its required so fumes don't build up in the car. Before starting check all areas for any evidence of smoke from melting insulation or shorting. It's not likely but you never know. Button up the the splash shield and tire and all trims you took off to route the cables. In over a year and a half I have run this setup with zero issues, it can be put back to stock in an hour and no one would ever know what was done. Start her up and enjoy the transfer of 35 pounds from the front to the rear!
Steve
Thanks Steve. Check this one out:
http://www.summitracing.com/parts/LAK-30301/?rtype=10
It has a nifty way to connect the stock battery cables. It's the only one I've seen that has that....
http://www.summitracing.com/parts/LAK-30301/?rtype=10
It has a nifty way to connect the stock battery cables. It's the only one I've seen that has that....
Don't let Gary see that.PeteInCT said:
Oh you mean he doesn't have one of these yet? Geez, how does he even take that sled out in public? ;D LOL
Pete
Cool setup, but I'm a little worried that the positve and negative terminals are on that bracket with only a nylon washer isolating the two. It probably is better than it looks in that picture. Basically what I did without the fancy kit. Once again if you want to DIY I would come up and lend a hand don't be shy asking.
Rick
I am surprised Gary hasn't done it yet, even with my numb butt I could feel the difference with the weigh moved to the back and lowered.
Steve
Cool setup, but I'm a little worried that the positve and negative terminals are on that bracket with only a nylon washer isolating the two. It probably is better than it looks in that picture. Basically what I did without the fancy kit. Once again if you want to DIY I would come up and lend a hand don't be shy asking.
Rick
I am surprised Gary hasn't done it yet, even with my numb butt I could feel the difference with the weigh moved to the back and lowered.
Steve
Grant 302
basic and well known psychic
2012YellowBoss said:
It's hard to argue specific part effects, when they generally work together to produce particular lift characteristics. But, in general, the splitter effects are primarily for the front of the car. The effect you are describing above sound largely from air dam and undertray effects. The splitter (base) in conjunction with the two does move the stagnation zone lower, but its primary effect is high pressure on its top side, resulting in front downforce. The LS splitter also replaces some of the undertray in front of the air dam and will further reduce turbulence, but again, primarily up front. Without the use of side skirting (or other aero mod) to extend the low pressure zone to the rear, the rear will not really be affected.
And maybe of interest, a splitter does not literally 'split' the air, as in creating a stagnation zone right on the tip of its lip. Airflow on part of the top of the splitter will actually flow from back to front...
2012YellowBoss said:
I don't think there's any other post in this thread referring to pointing the splitter up or down. But if you are talking about the effects I mention from brake dive, these are real world dynamic effects. And we've seen how close the splitters get to the ground under braking.
2012YellowBoss said:
The roof flaps kill lift when sideways or backwards and do nothing when the car is moving forward.
2012YellowBoss said:
I'm not sure about this point, but physics applies the same to the OP and Joe Foster. ;D
- Thread starter
- #37
pufferfish
Supporting Vendor
well, i picked up the LS rear spoiler and got it on with little trouble. then moved to the front to install the LS splitter and bolt holes arent anywhere near where they should be. there's also a set of contoured pieces bolted to the top of the splitter that don't line up with any of my bodywork. so, i went to the track without the splitter on
i am wondering if i got a 2013 LS splitter. i can't find any pics or install instructions for it to determine if that is what i have. does anyone have one here that they can add pics of (not installed) so i can confirm? i belive i may be stuck with it as i bought it on ebay and they say "no returns", but it is clearly not the part number they sold me. i contacted them, so we will see.
i am wondering if i got a 2013 LS splitter. i can't find any pics or install instructions for it to determine if that is what i have. does anyone have one here that they can add pics of (not installed) so i can confirm? i belive i may be stuck with it as i bought it on ebay and they say "no returns", but it is clearly not the part number they sold me. i contacted them, so we will see.
pufferfish said:well, i picked up the LS rear spoiler and got it on with little trouble. then moved to the front to install the LS splitter and bolt holes arent anywhere near where they should be. there's also a set of contoured pieces bolted to the top of the splitter that don't line up with any of my bodywork. so, i went to the track without the splitter on
i am wondering if i got a 2013 LS splitter. i can't find any pics or install instructions for it to determine if that is what i have. does anyone have one here that they can add pics of (not installed) so i can confirm? i belive i may be stuck with it as i bought it on ebay and they say "no returns", but it is clearly not the part number they sold me. i contacted them, so we will see.
PM me your email address, I'll send you the original 2012 splitter install instructions.
-Pete
My LS spoiler is one piece ???
Sorry sir but you're not correct, at least as compared to my stock LS splitter. It's all one piece, Ford PN # M-16601P-MB. It's also shown as 1 piece in the PDF instructions I have. Maybe Ford offered more than 1 design, I don't know. I'll send you the install instructions via email.
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