What gains can I expect to see?
05-14-2009, 09:42 PM
#21
Join Date: May 2009
Location: Palm Island, FL
Posts: 8
From these mods. UDP?
JLT cold air intake?
Throttle body?
o/r xpipe?
Apparently kirk thinks it's a lot less than I do, so I was wondering if anyone has done them before and after dynos and can verify how much you should gain from these?
Keep in mind it's for a 4v 2001 Cobra
JLT cold air intake?
Throttle body?
o/r xpipe?
Apparently kirk thinks it's a lot less than I do, so I was wondering if anyone has done them before and after dynos and can verify how much you should gain from these?
Keep in mind it's for a 4v 2001 Cobra
JLT CAI some claim 8-12 rwhp i'd say maybe 5-6
skip the TB
x pipes usually get 1-2 hp over h pipes but im not sure on the actual hp gains
05-15-2009, 12:30 AM
#22
2nd Gear Member
Join Date: Apr 2009
Location: Near China now...
Posts: 314
You see well its all amatter of aerodynamics. Aerodynamics is a highly refined science that vies for position with other key vehicle design considerations such as styling and ergonomics. It's importance with respect to the operating efficiencies of a vehicle is undisputed but manufacturers must steer a balanced path between the push an pull of the many other aspects of a car necessary to sell it to the consumer.
Aerodynamics started life as much as an art as a science. Early experiments used fish as the inspiration. Their sleek form was considered important to facilitate fast movement, but the precise details were not yet understood and developments were largely based on trial and error. It was as a result of this approach that the 'teardrop' form was conceived.
Ultimately a cars performance is dictated by it’s tyres. The more friction or grip they have with the road, the faster a car can corner, accelerate and brake. There are many weird and wonderful ways to get the tyres themselves to grip better, from compounds of rubber to their internal construction. One simple way to increase grip though is just to push them onto the road more. Sounds obvious eh? Of course you could do this by adding weight, but that would compromise other aspects of the car’s performance. The more mass a car has the more energy that is needed to accelerate it and keep it on the road, so really you want a way to push the car down, but without adding mass. That’s where downforce comes in, using the airflow passing over – and under – the car to push it down into the road.
An important idea to understand when thinking about downforce is the Bernouilli Principle for fluid dynamics. In short all this says is that the faster a fluid flows the lower its pressure. In our case, the fast that air is flowing over the surface of a car, the lower it’s pressure. (This is a vast simplification, but in general true.)
Aerodynamics started life as much as an art as a science. Early experiments used fish as the inspiration. Their sleek form was considered important to facilitate fast movement, but the precise details were not yet understood and developments were largely based on trial and error. It was as a result of this approach that the 'teardrop' form was conceived.
Ultimately a cars performance is dictated by it’s tyres. The more friction or grip they have with the road, the faster a car can corner, accelerate and brake. There are many weird and wonderful ways to get the tyres themselves to grip better, from compounds of rubber to their internal construction. One simple way to increase grip though is just to push them onto the road more. Sounds obvious eh? Of course you could do this by adding weight, but that would compromise other aspects of the car’s performance. The more mass a car has the more energy that is needed to accelerate it and keep it on the road, so really you want a way to push the car down, but without adding mass. That’s where downforce comes in, using the airflow passing over – and under – the car to push it down into the road.
An important idea to understand when thinking about downforce is the Bernouilli Principle for fluid dynamics. In short all this says is that the faster a fluid flows the lower its pressure. In our case, the fast that air is flowing over the surface of a car, the lower it’s pressure. (This is a vast simplification, but in general true.)
To answer: maybe 8-10 rwhp and 6-8 ft lbs. Yes I have hundreds of dyno pulls that verify such numbers. You will also lose low end torque because of the larger TB and CAI. They slow down intake air velocity which manifests as lower torque #'s at low rpm's.
EDIT: I was thinking GT, add 5 rwhp for Cobra. There are so many factors that go into this too...an O/R X-pipe on a blown cobra can be worth as much as 35 hp, likewise on a CAI when done with a tune. But on an NA Cobra, the heads just breathe so well that you're hurting lower numbers because they're so efficient up top. Put it this way if you want to see if your parts will make any power...
Place a vacuum gauge in your inlet tube and rev the engine through the power band...if there is vacuum present at WOT at any rpm that represents an inlet restriction that is costing you HP. You can systematically work your way all the way to the intake manifold dong this to find out which part in your inlet is causing the restriction.
Last edited by Smokin04; 05-15-2009 at 02:40 AM.
05-20-2009, 02:06 AM
#23
I read F1technical.net as well...you going to plagerize/copy and paste the whole site or just bits and pieces. Got any thoughts of your own on how much HP his bolt-ons will add?
To answer: maybe 8-10 rwhp and 6-8 ft lbs. Yes I have hundreds of dyno pulls that verify such numbers. You will also lose low end torque because of the larger TB and CAI. They slow down intake air velocity which manifests as lower torque #'s at low rpm's.
EDIT: I was thinking GT, add 5 rwhp for Cobra. There are so many factors that go into this too...an O/R X-pipe on a blown cobra can be worth as much as 35 hp, likewise on a CAI when done with a tune. But on an NA Cobra, the heads just breathe so well that you're hurting lower numbers because they're so efficient up top. Put it this way if you want to see if your parts will make any power...
Place a vacuum gauge in your inlet tube and rev the engine through the power band...if there is vacuum present at WOT at any rpm that represents an inlet restriction that is costing you HP. You can systematically work your way all the way to the intake manifold dong this to find out which part in your inlet is causing the restriction.
To answer: maybe 8-10 rwhp and 6-8 ft lbs. Yes I have hundreds of dyno pulls that verify such numbers. You will also lose low end torque because of the larger TB and CAI. They slow down intake air velocity which manifests as lower torque #'s at low rpm's.
EDIT: I was thinking GT, add 5 rwhp for Cobra. There are so many factors that go into this too...an O/R X-pipe on a blown cobra can be worth as much as 35 hp, likewise on a CAI when done with a tune. But on an NA Cobra, the heads just breathe so well that you're hurting lower numbers because they're so efficient up top. Put it this way if you want to see if your parts will make any power...
Place a vacuum gauge in your inlet tube and rev the engine through the power band...if there is vacuum present at WOT at any rpm that represents an inlet restriction that is costing you HP. You can systematically work your way all the way to the intake manifold dong this to find out which part in your inlet is causing the restriction.
awww, did u copy and paste sum of that into ur browser to discover that joke inspector clouseau??
05-20-2009, 04:52 PM
#27
2nd Gear Member
Join Date: Oct 2006
Posts: 263
X pipe $80-$100 bucks used
K&N $50
TB- $150
Pullys- $125
Total of about $400- $425 should give you 20 HP on a good day and maybe 2 or 3 tenths in the quarter.
Or you can bolt in some 4.30s for $425 installed and not gain horsepower, but pick up a good 1/2 second or more in the quarter.
Trust me for the money you're looking to spend, 4.30s are better. Research the gears, you will thank me later.
K&N $50
TB- $150
Pullys- $125
Total of about $400- $425 should give you 20 HP on a good day and maybe 2 or 3 tenths in the quarter.
Or you can bolt in some 4.30s for $425 installed and not gain horsepower, but pick up a good 1/2 second or more in the quarter.
Trust me for the money you're looking to spend, 4.30s are better. Research the gears, you will thank me later.
05-20-2009, 05:01 PM
#28
6th Gear Member
Join Date: Mar 2007
Location: Yadkin, Nc
Posts: 5,183
From these mods. UDP?
JLT cold air intake?
Throttle body?
o/r xpipe?
Apparently kirk thinks it's a lot less than I do, so I was wondering if anyone has done them before and after dynos and can verify how much you should gain from these?
Keep in mind it's for a 4v 2001 Cobra
JLT cold air intake?
Throttle body?
o/r xpipe?
Apparently kirk thinks it's a lot less than I do, so I was wondering if anyone has done them before and after dynos and can verify how much you should gain from these?
Keep in mind it's for a 4v 2001 Cobra
im gonna say 8 rwhp for the intake
6 rwhp for the TB
and 8rwhp for the x pipe
05-21-2009, 12:03 AM
#29
I always jizz first
Thread Starter
Join Date: Jun 2008
Location: TX
Posts: 967
X pipe $80-$100 bucks used
K&N $50
TB- $150
Pullys- $125
Total of about $400- $425 should give you 20 HP on a good day and maybe 2 or 3 tenths in the quarter.
Or you can bolt in some 4.30s for $425 installed and not gain horsepower, but pick up a good 1/2 second or more in the quarter.
Trust me for the money you're looking to spend, 4.30s are better. Research the gears, you will thank me later.
K&N $50
TB- $150
Pullys- $125
Total of about $400- $425 should give you 20 HP on a good day and maybe 2 or 3 tenths in the quarter.
Or you can bolt in some 4.30s for $425 installed and not gain horsepower, but pick up a good 1/2 second or more in the quarter.
Trust me for the money you're looking to spend, 4.30s are better. Research the gears, you will thank me later.
05-21-2009, 02:39 AM
#30
6th Gear Member
Join Date: Mar 2007
Location: Chicago, IL
Posts: 6,169