RAM AIR and record breaking speed

mybirdcanfly

Registered User
I have done 175mph with my modified SC.
I have custom ram air that gets me about 4 to 5 lbs extra boost that climbs starting at 90 and seems to level off boost wise at about 120mph. Other mods might equal 275hp. Total could be 300hp with ram air. I have read a long time if I remember right that each pound of boost could be about 7 to 8hp.

I remember an old SCCOA magazine, vintage 10 years or more ago that I can't find that had the supercoupe running 205mph at Bonneville, holding some class record at the time. I can't find any info on this on the web. The picture of the car showed the engine compartment with intake mods, most likely a high flow exhaust was installed, however at that time I do not believe the engine could be modified with much more than 400hp.

I have had an argument now with someone, that supplies all sorts of comparisons and calculations, that this SC must have had at least 500hp.

My point is this, and it suddenly dawned on me. It is very unique to have a car stock with only 215hp go 160mph stock. Is there any other car that you can think of with as low horsepower going so fast? Gearing is not the biggest impediment to this type of speed, it is hp and aerodynamics.

Meanwhile I did find some info on the aerodynamics of the SC. Sorry to copy all this but I cannot find the website I got this from. Note the coefficient of drag has to be multiplied by the frontal area to get the real total force that the car encounters when in the wind.

The SC may actually be better than this, that is one of my questions. If this is taken with a standard body, the SC ground effects should make it better.

The other question is, if it is true that the mods at the time would have given this car at most 400hp, was the secret ram air?

Make Model Year Cd Height (In) Width (In) Frontal Area (ft^2) CdA
Honda Insight 2000 - 2006 0.25 53.3 66.7 20.7 5.18
Honda CRX HF 1988 - 1991 0.29 50.1 65.9 19.3 5.59
Honda CRX 1988 - 1991 0.30 50.1 65.9 19.3 5.78
Toyota MR2 1991 - 1995 0.31 48.6 66.9 19.0 5.88
Toyota MR-Spyder 1999 - 2007 0.31 48.8 66.7 19.0 5.89
Nissan 200SX SE 1991 - 1994 0.30 50.8 66.5 19.7 5.91
Mitsubishi Eclipse GS-T 1995 - 1999 0.29 51.0 68.3 20.4 5.92
Toyota MR2 1985 - 1989 0.32 49.2 65.5 18.8 6.02
Toyota Prius 2004 - 0.26 58.7 67.9 23.3 6.05
Honda CRX 1984 - 1987 0.32 50.8 63.9 18.9 6.06
Honda Civic Hybrid 2005 - 0.27 56.3 69.0 22.7 6.12
Acura NSX 1995 - 2005 0.32 46.1 71.3 19.2 6.13
Toyota Paseo 1992 - 1995 0.32 50.5 65.2 19.2 6.15
Honda Civic Hybrid 2003 - 2005 0.28 56.3 67.5 22.2 6.21
Toyota Paseo 1996 - 1998 0.32 51.0 65.4 19.5 6.23
Nissan 300ZX Turbo 1990 - 1996 0.31 49.2 70.5 20.2 6.27
Toyota Yaris 2007 - 0.29 56.5 66.5 21.9 6.36
Mitsubishi Mirage Coupe 1991 - 1996 0.32 51.4 66.5 19.9 6.38
Mazda RX-7 1992 - 2002 0.33 48.4 68.9 19.5 6.42
Acura Integra 1994 - 2001 0.32 51.9 66.7 20.2 6.46
Geo Metro 4dr 1995 - 1997 0.32 55.4 62.6 20.2 6.47
Toyota Tercel 1995 - 1999 0.32 53.2 65.4 20.3 6.49
Toyota Prius 2000 - 2003 0.29 57.6 66.7 22.4 6.50
Volkswagen Jetta 1993 - 1999 0.30 56.1 66.7 21.8 6.55
Mercury Cougar 1999 - 2002 0.31 52.2 69.6 21.2 6.57
Toyota Echo 2000 - 2005 0.29 59.4 65.4 22.7 6.57
Toyota Corolla 1998 - 2002 0.31 54.5 66.7 21.2 6.57
Volkswagen Passat 1995 - 1997 0.31 56.4 67.5 21.4 6.64
Honda Prelude 1997 - 2001 0.32 51.8 69.0 20.8 6.67
Toyota Supra 1993 - 2002 0.32 50.2 71.3 20.9 6.68
Mercedes-Benz CL500 1998 - 2000 0.28 55.0 73.1 23.9 6.69
Nissan 350Z 2002 - 0.31 51.9 71.5 21.6 6.71
Honda S2000 2000 - 0.33 50.6 68.9 20.3 6.71
Honda Civic Del Sol 1992 - 1997 0.35 49.4 66.7 19.2 6.73
Toyota Corolla 2009 - 0.29 57.7 69.3 23.3 6.76
Hyundai Tiburon GT 2002 - 0.32 52.3 69.3 21.1 6.77
Volkswagen Jetta sedan 2000 - 2005 0.30 56.7 68.3 22.6 6.78
Toyota Celica GT-S 1994 - 1999 0.34 50.1 68.3 20.0 6.79
Toyota Corolla 1993 - 1997 0.33 53.5 66.3 20.7 6.83
Toyota Corolla 2003 - 2008 0.30 58.5 66.9 22.8 6.85
Ford Thunderbird 1989 - 1997 0.31 52.8 72.0 22.2 6.87
Chrysler Sebring 1995 - 2000 0.32 53.0 69.7 21.5 6.90
Saturn SC2 1997 - 2002 0.33 52.2 67.3 20.9 6.90
Acura RSX 2002 - 2004 0.32 54.5 67.9 21.6 6.91
Mazda Miata 1998 - 2005 0.38 47.3 66.1 18.2 6.93
Nissan Sentra 1995 - 1999 0.33 54.5 66.6 21.2 6.99
Volkswagen Jetta wagon 2000 - 2005 0.30 58.5 68.3 23.3 6.99
Mini Mini Cooper S 2001 - 2006 0.33 55.8 66.5 21.3 7.03
Nissan Altima coupe 2007 - 0.31 55.3 70.7 22.8 7.07
Hyundai Elantra 1996 - 2000 0.33 54.9 66.9 21.4 7.07
Nissan Altima hybrid 2007 - 0.30 58.1 69.6 23.6 7.08
Nissan Sentra 1991 - 1994 0.35 53.0 65.6 20.3 7.10
Mitsubishi Eclipse GTS 2000 - 2005 0.35 51.6 68.9 20.4 7.14
Nissan 200SX SE-R 1995 - 1999 0.34 54.2 66.6 21.1 7.16
Scion Tc 2005 - 0.32 55.7 69.1 22.5 7.18
Nissan Sentra 2000 - 2006 0.33 55.5 67.3 21.8 7.19
Honda Civic SI 1996 - 2000 0.34 54.1 67.1 21.2 7.20
Nissan Altima 1998 - 2001 0.32 55.9 69.1 22.5 7.21
Toyota Tercel 1991 - 1994 0.36 53.1 64.8 20.1 7.23
Scion Xa 2004 - 2007 0.31 60.2 66.7 23.4 7.26
Volkswagen Jetta 2006 - 0.31 57.4 70.1 23.5 7.28
Nissan Versa 2004 - 0.31 60.4 66.7 23.5 7.29
Acura CL 2000 - 2003 0.32 55.5 70.6 22.9 7.31
Volkswagen Passat Wagon 1995 - 1997 0.33 58.7 67.5 22.3 7.36
Hyundai Elantra wagon 1996 - 1997 0.33 57.4 66.9 22.4 7.39
Nissan Altima sedan 2007 - 0.31 57.9 70.7 23.9 7.40
Ford Escort 1997 - 2002 0.36 52.3 67.4 20.6 7.40
Volvo C70 Coupe 1997 - 2005 0.32 55.1 72.0 23.1 7.41
Nissan Altima 1993 - 1997 0.34 55.9 67.1 21.9 7.44
Chevrolet Camaro 1993 - 2002 0.34 51.3 74.1 22.0 7.48
Pontiac Firebird Trans Am 1993 - 2002 0.34 52.0 74.5 22.0 7.48
Hyundai Sonata 2006 - 0.32 58.0 72.1 23.5 7.53
Chevrolet Cavalier 1995 - 2005 0.36 53.2 67.4 20.9 7.53
Hyundai Elantra 2001 - 2006 0.34 56.1 67.9 22.2 7.55
Hyundai Elantra wagon 1998 - 2000 0.33 58.8 66.9 22.9 7.57
Scion Xd 2008 - 0.32 60.0 67.9 23.8 7.60
Acura CL 1997 - 1999 0.34 54.7 70.1 22.4 7.61
Hyundai Elantra 2007 - 0.32 58.3 69.9 23.8 7.61
Nissan Altima 2002 - 2006 0.32 57.9 70.4 23.8 7.61
Subaru Impreza WRX 2002 - 2007 0.34 56.7 68.1 22.5 7.66
Honda Accord Ex Coupe 1998 - 2002 0.34 55.1 70.3 22.6 7.68
Subaru Impreza 2.5RS 1993 - 2001 0.36 55.5 67.1 21.7 7.82
Hyundai Elantra touring 2007 - 0.33 59.8 69.5 24.2 8.00
Toyota Matrix 2003 - 2008 0.32 61.6 69.9 25.1 8.04
 
I think most people will concur that 145mph is stock, not 160mph. To run 160mph will require at least some mods.

Yes, the Bonneville car made well over 400hp. In fact it may have at one time made as much as 700hp but it had many modifications and did not in any way represent a stock SC motor.
 
8th place in terms of RWD?

Another thing that I noticed, not that this is the most comprehensive list in the world, but for those cars that have RWD, or that you would even want to be going 200mph in, the SC is 8th down on the list if I counted right.

Also the RX-7 has done well in these over 200mph land speed categories, it is high on the list.
 
Pretty much stock Mark VIII ran 200 mph. I know they locked out OD on it and lowered it a touch, but that was about the only mods done to it. See if I can find the website. Been a few years.



Found it. http://www.markviii.org/LOD2/bonneville.htm

Guess, it was 183mph not 200.

Of course the only thing in common between the 2 is the chasis, tranny and rearend. Engines are completely different animals. DOHC 4.6 is still makeing hp at 8,000 rpm, but marks do tend to weigh a bit more.
 
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What modifications have you done to your car to achieve 175 besides a ram air?
What did you use to calculate your mph?
 
Also the RX-7 has done well in these over 200mph land speed categories, it is high on the list.

The 200 mph LS cars also have pans on the underside, large wheel discs that smooth the air over the tires/wheels, etc. that aid airflow and creation of downforce. They are a far cry from the stockers that roam the street. Apples & oranges...
 
I have done 175mph with my modified SC.
I have custom ram air that gets me about 4 to 5 lbs extra boost that climbs starting at 90 and seems to level off boost wise at about 120mph. Other mods might equal 275hp. Total could be 300hp with ram air. I have read a long time if I remember right that each pound of boost could be about 7 to 8hp.

I'm confused. What do you mean when you say your boost climbs starting about 90 and levels off at 120? How much boost are you making and are you saying that you remain in boost the whole time??

I would also like to hear more about your custom ram air setup. You say it adds up to 4-5 lbs of boost? That sounds interesting!!

Ira
 
The numbers are very loose for the aero packages. The 96 and 97 Birds are better with aero as apposed to the 89-95 birds.
 
more links

This was before Coy and others developed mods as far as I can remember. It ran 205, I remember that. I can't see how the mods back then could go over 400hp.

Other things I just found:

Bonneville Racing.com - tells of classes
http://www.bonnevilleracing.com/car-classifications.asp

World's fastest RX-7
http://www.bonnevilleracing.com/car-classifications.asp

Reference to possible land speed record for SC at 214mph
http://www.motortopia.com/garage/cars/Spinning15

A list of land speed records, but still trying to get info on the cars/hp/etc
http://www.scta-bni.org/

Slide show of possibly all cars from Bonneville?
http://purplesagetradingpost.com/sumner/bville-cars-1/bville-all numbers.html

A link to someone who has collected many links on land speed records
http://www.purplesagetradingpost.com/sumner/bvillecar/bvillelinks.htm
 
mods for 175

I can't of course swear to the 175 on the button via radar, this was a calculation as I was doing 4200 in 5th gear, I don't have the calculation right now I'll find it.

I have raced superbikes at top speed now for years. I raced and passed one that later came up to me and said, "how fast were you going#@#@!, I was doing 160".

After ram air installation this car began walking away from cars at 90mph that it never did before.

mods are for this 89 5-speed:
S-mod
shorty headers
no cats, custom exhaust
C&N MAF
fully air tight ram air that gives 4 to 5 lbs boost 90 - 120mph
K&N + ram air canal goes directly to airbox

With this setup I can pull 30 to 40mph increased speed over stock SCs I have in certain 1/2 mile runs.
This ram air design has just been put on a stock SC auto this summer, with incredible increase in performance. It is a noticeable improvement in performance starting at about 75mph. At 100 it is considerably different than stock. I get the same 5 lbs boost, no difference there.

The stock ram air car is now sufficient to take WRXs at 90 to 120 range, and a pack of others at high speed, where it was basically trying to run with them before.

MPH differences in certain 1/2 mile runs vs stock in the 80 to 120 mph range are about 10 to 15 mph better.
 
It must be a pretty big ram air. My car had fully sealed ram air system on it when I purchased it. If I had to guess, the air scoop is 3"x12". I disconnected it and couldn't tell if it made a difference or not and testing included speeds over 130 on a late model 145 mph speedometer.
 
how to do the mod

1. remove air silencer
2. get 4 inch black flexible corrugated drain pipe from home depot
3. route from front of car in hole in front cowl and up to air box, the pipe fits perfectly into the oval hole, but you have to simply form the end to that shape
4. using exacto knife cut off excess to make fit near perfect. Seal with any gasket cement, I use dow corning 3140 RTV which ensures lasting air tight seal
5. Leave plenty of excess in front of car to play with placement, I found the slightly angled to the front looks good and gives the maxmum boost.

tell me how to load a picture and I'll put a picture up I have a JPG but it says put a http: address

this is my summary of theory on the whole thing:
- The science of RAM Air is not very popular and not tested, they usually only blow cold air into the front of a vehicle using shop fans to get any advertised results
- Home projects have found gains, but there is no consensus on the whole thing
- The gains require excessive speeds, therefore most of the public wouldn't be interested.

All I can tell you is if you do it, and you run evenly with anyone till 80 or 90, this will mean you beat them thereafter.
 
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I can't of course swear to the 175 on the button via radar, this was a calculation as I was doing 4200 in 5th gear, I don't have the calculation right now I'll find it.

Stock 225/60R16 tires, stock 2.73 rear end, 5th gear, 4200 rpms is 163 mph.

Also please note that most SC tach's show rpms higher than what the engine is actually doing. 3900 = 151 mph.
 
Here is my scoop.
DSC01474.jpg
 
How do you not suck up water with that? Dont think that will allow my MP air dam to work properly.

Well when I first got the car the air filter was horribly dirty and I was thinking it hadn't been cleaned in years. This thing is light a street sweeper. I'm always cleaning rocks and crap from below the filter.
 
So what do you want to know about the Bonneville SC? Yes, it set the Stock Bodied Class record in 90 at around 195 MPH and again in 92 at 205 and change. It presently resides in Jack Rousch's private museum in Livonia MI. I have seen it there twice and have taken pictures of it as well as know the Project Manager for the car.
 
I must be missing something here:confused:I read this thread and see no statement as to what kind of boost you are running. What does your boost gauge read before 90MPH. What does it read when you have gained your extra 4 or 5 lbs of boost. Is this a stock boost gauge (not exactly know for their accuracy) Not disagreeing with the ram air effect adding to top end speed but your statements are not including enough facts. 90blkbrd,s car has shown high top end speeds in the 1/4 mile so ram air is a nice mod. It would be nice to be able to pop out a headlight like the Pontiac boys and run down the 1/4 mile and get the ram effect. Other than that I dont think to many SC owners are running down the road at 150+:rolleyes:

Ken
 
torque could be the key

Yes I would like to know more about that car, the whole question was did it have RAM AIR and was it around 400hp.

I'll accept the 163mph or whatever, I ran out of road and had much more left. I actually have spent a lot of time planning for and making these runs. It is very risky and if caught of course you're dead meat. I don't have the tires now to do it but it was fun. I planned the run by getting juiced right before the bottom of a hill and getting to very near readline in 4th. By the time I shifted to 5th I would have another 2 miles of road. In that 2 miles is the 1st half somewhat of a hill and then after I go over that I am really flying at high speed. So this is not a true level all the way but I have raced superbikes through this procedure and past or kept with them depending on the jump they got.

The boost is normally around 7 to 8, it dropped after the installation of exhaust and headers. It will rise to about 12 at top speed under RAM AIR.

I do believe these 5 speeds could do 160 stock. Another thought is the TORQUE is a factor in why a car with such low horse power can go so fast (but of course good aero does help). There are many arguments about torque/horsepower but there is no question at/near redline these cars have higher torque than unsupercharged. A car pulling around 300lb-ft of torque at 4000 rpm is going to have the ummph to arm wrestle the wind force.

I have found that the effect of high speed wind is roughly a cube law effect.

If you could agree the 215 hp gets 160mph

then: Power necessary for 200 mph = 215 (200/160) 3 = about 420hp but this also then assumes that there are gobs of torque that go with it.

My basic conclusion is if this car can do 200mph or so with 400 to 500hp that is indeed quite a feat.

My references for power gains came from here.
http://www.musclemustangfastfords.com/tech/mmfp_0707_1990_thunderbird_super_coupe/photo_05.html

I believe the RAM AIR is producing similar effects to these two pulley mods. But in the end I am down on total boost compared to these mods, but I wonder?... mine is not at the expense of stressing the supercharger more.

I agree with this statement and why I love the SC
source:

http://store.speedindustry.biz/Store/OurShop/?id=20270

"If peak horsepower is not the most important thing, then what is? In my opinion it is more important to look at the shape of the torque curve and the area under the curve than the peaks. Cars that have a nice flat torque curve that is carried all the way across the rpm range are the cars that we truly enjoy driving and which perform the best on the track."
 
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