Theoretical top speed on a stock tranny?
#16
12-31-2012, 11:40 AM
Join Date: Jul 2008
Location: Houston
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Oh Lord. Not again. Keep it civil please you two.
#18
12-31-2012, 12:03 PM
yes that is definetly part of it and as you say there are many factors at play but the wind does in fact wreak havoc on the short wheelbase Porsches.Ive seen it happen to Bello and even at the under 180 mph trap speeds at TI my car felt spooky under hard acceleration on Saturday when there was a 20mph crosswind
#20
12-31-2012, 12:10 PM
yes that is definetly part of it and as you say there are many factors at play but the wind does in fact wreak havoc on the short wheelbase Porsches.Ive seen it happen to Bello and even at the under 180 mph trap speeds at TI my car felt spooky under hard acceleration on Saturday when there was a 20mph crosswind
#21
12-31-2012, 03:29 PM
Drop it till it almost scrapes pavement, Vent the fenders, add a rear diffuser, build a removeable dam for the front openings then tape off all seams and gaps prior to running; then get a bit of drag back by adding a very low incidence splitter and a set of low incidence dive planes up front. When that was all done I would do a string test on the aerodynamics of the car then I would add a few small aerofins where needed to clean up the airflow even more.
Do it right and you will not add any drag, plus you then have a way more stable car.
Last edited by Engine Guy; 12-31-2012 at 03:35 PM.
#22
12-31-2012, 04:21 PM
Exactly. Plenty of ways to make them more stable without pushing down. As built, they have a fairly good drag coefficient number but still scoop a lot of air. I'm making a solid underpan of CF sheet for the car now.... 
Quite simple actually but do you want to go there.
Drop it till it almost scrapes pavement, Vent the fenders, add a rear diffuser, build a removeable dam for the front openings then tape off all seams and gaps prior to running; then get a bit of drag back by adding a very low incidence splitter and a set of low incidence dive planes up front. When that was all done I would do a string test on the aerodynamics of the car then I would add a few small aerofins where needed to clean up the airflow even more.
Do it right and you will not add any drag, plus you then have a way more stable car.
Drop it till it almost scrapes pavement, Vent the fenders, add a rear diffuser, build a removeable dam for the front openings then tape off all seams and gaps prior to running; then get a bit of drag back by adding a very low incidence splitter and a set of low incidence dive planes up front. When that was all done I would do a string test on the aerodynamics of the car then I would add a few small aerofins where needed to clean up the airflow even more.
Do it right and you will not add any drag, plus you then have a way more stable car.
#25
01-01-2013, 07:46 AM
#26
01-01-2013, 08:11 AM
Todd has already gone in excess of 209MPH, and I believe he'll have more HP this time around.
At this point it's a matter of how fast he can get over a 1 Mile distance from a standing start.
His biggest challenge will be conditions and aero.
ok so the trans will go to 209 what amount of rwhp is needed to push the car to 209?
At this point it's a matter of how fast he can get over a 1 Mile distance from a standing start.
His biggest challenge will be conditions and aero.
#27
01-01-2013, 08:34 AM
With my car making alot more whp than it was when it ran 231 i think its easily capable of going over 240 i just dont think the aero is there to do it.At this point i think it would be stupid to take the car back without doing some sort of aerodynamics testing.Getting the car in a wind tunnel with an aero engineer would be the ticket.Making any kind of aero changes without one would just be shooting arrows in the sky and actually is dangerous.I would advise anyone going back to be careful when making aero changes especially with things like flat panel bottoms.the car could just take flight if you get too much air under it or happen to spin sideways.I think one of the easiest and safest aero mods is to rake the car and get the front lower than the rear to keep front end lift to a minimum.I dont want to see anyone get hurt.
#29
01-01-2013, 09:15 AM
With my car making alot more whp than it was when it ran 231 i think its easily capable of going over 240 i just dont think the aero is there to do it.At this point i think it would be stupid to take the car back without doing some sort of aerodynamics testing.Getting the car in a wind tunnel with an aero engineer would be the ticket.Making any kind of aero changes without one would just be shooting arrows in the sky and actually is dangerous.I would advise anyone going back to be careful when making aero changes especially with things like flat panel bottoms.the car could just take flight if you get too much air under it or happen to spin sideways.I think one of the easiest and safest aero mods is to rake the car and get the front lower than the rear to keep front end lift to a minimum.I dont want to see anyone get hurt.
There are numerous simple books out there on car aero that would coach you through many simple mods that would make a world of difference and if you ever want to try again you can to call me I would be glad to help. I do know a thing or two about the aerodynamics of going fast even if it is meant to take flight or not take flight. The big thing with wanting to not take flight is knowing what to do with multiple air paths coming together, a little knowledge there and a few simple strakes could really help out.
Here is a list of the 7 auto speed articles on the subject, they are actually not all that bad.
Aero testing part one http://www.autospeed.com/A_108656/cms/article.html
Pt 2 http://www.autospeed.com/A_108674/cms/article.html
Pt 3 http://www.autospeed.com/A_108675/cms/article.html
Vortex generators for auto
Pt 1 http://www.autospeed.com/A_3058/cms/article.html
Pt 2 http://www.autospeed.com/A_3059/cms/article.html
Pt 3 http://autospeed.com/A_3060/cms/article.html
Pt 4 http://autospeed.com/cms/A_3061/arti...popularArticle
Last edited by Engine Guy; 01-01-2013 at 09:45 AM.
#30
01-01-2013, 09:34 AM
Joe there are simple proven changes that even a 1/2 wit idiot could make without worry. The list I made in my prior post has many of them. Especially venting the front fender and closing off the front openings. OK yes they would require some basic though; but a very simple string test would tell you all that you need to know. Even NASA uses string tests to check flow. Here I found this picture and article to show you what I mean if you do not know. I did not read it yet but the picture serves to explain what I mean. And for your viewing pleasure it is even a Porsche. http://www.racingonthecheap.com/aerodynamics/
There are numerous simple books out there on car aero that would coach you through many simple mods that would make a world of difference and if you ever want to try again you can to call me I would be glad to help. I do know a thing or two about the aerodynamics of going fast even if it is meant to take flight or not take flight. The big thing with wanting to not take flight is knowing what to do with multiple air paths coming together, a little knowledge there and a few simple strakes could really help out.
There are numerous simple books out there on car aero that would coach you through many simple mods that would make a world of difference and if you ever want to try again you can to call me I would be glad to help. I do know a thing or two about the aerodynamics of going fast even if it is meant to take flight or not take flight. The big thing with wanting to not take flight is knowing what to do with multiple air paths coming together, a little knowledge there and a few simple strakes could really help out.
