Just Dynoed
11-12-2002 | 01:42 AM
#14
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Again, I will remind everyone that he used a Mustang dyno, which is not the same as a Dynojet dyno and as such the numbers are not comparable.
For a Mustang dyno, the numbers that Ropeman put out are very respectable. I'd expect to see a low 130 on a dynojet roller setup.
For a Mustang dyno, the numbers that Ropeman put out are very respectable. I'd expect to see a low 130 on a dynojet roller setup.
11-12-2002 | 05:14 AM
#15
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Dont forget when your modding a lot of cars, Hyundais in general, by adding stuff to the engine it messes with its original air fuel intakes, your car is all computerized to run at a certain spec, when you put parts in the would generally INCREASE performance, you could actually be bogging your car down.
11-12-2002 | 06:51 AM
#16
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QUOTE
D4Damager:
Dont forget when your modding a lot of cars, Hyundais in general, by adding stuff to the engine it messes with its original air fuel intakes, your car is all computerized to run at a certain spec, when you put parts in the would generally INCREASE performance, you could actually be bogging your car down.
i doubt its that...Dont forget when your modding a lot of cars, Hyundais in general, by adding stuff to the engine it messes with its original air fuel intakes, your car is all computerized to run at a certain spec, when you put parts in the would generally INCREASE performance, you could actually be bogging your car down.
ECU compensates for NA mods... as long as the fuel system remains untouched, hes alright
11-12-2002 | 07:05 AM
#17
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Indeed, this is the (sometimes double-sided) beauty of a MAF-based fuel system.
Unlike you folks across the ocean, all the North American Tiburons and Elantras up to 2001 were MAF-based, instead of the more common MAP. By using a MAF, or mass air flow sensor, the computer can actually measure the exact mass of the incoming air and make fuel adjustments accordingly. When using a MAP, or manifold absolute pressure sensor, you can only look at general intake pressure instead of total airflow.
Why is this important?
Let's say you have a 100% stock Tiburon, but the computer delivers fuel based on a MAP system. When you put your foot on the floor, the MAP sensor reads zero vacuum. The computer knows that a stock engine at zero vacuum needs 200cc/min of fuel (for example). Now you bolt on an intake, a bigger throttle body, a new manifold, a set of wild cams, a header and a full exhaust system. You apply full throttle, and the MAP sensor will report zero vacuum again. Guess what? The computer cannot see anything that you changed, so it assumes that zero vacuum = 200cc/min of fuel. The engine goes lean, problems ensue...
A MAF sensor doesn't exhibit this problem. A fully stock Tiburon with your foot on the floor may register 12.8lbs/min of air coming in thru the MAF sensor, so the onboard computer sends 200cc/min of fuel (as an example again). But you bolt-on all those parts I listed above, and now pressing your foot to the floor makes the MAF sensor register 16.2lbs/min of air coming in. The computer sees the increase, and accordingly adjusts fuel delivery to 240cc/min instead.
No lean condition, no bog, car works as you would expect it to.
Tuning a MAF-based car is a significantly different exercise than a MAP-based car. This is why (I believe) Alpine is having so many problems with getting their turbocharger and supercharger kits really well tuned in the North American market -- because they are still wanting to treat it like a MAP system.
The MAF sensor on the Tiburon/Elantra BETA engines is good to at least 240 wheel horsepower; it may even be higher. The only real problem is that the stock ECU was never meant to accept such a high signal from the MAF (no stock engine would ever move that much air, so the ECU thinks it's an error) and as such you run into certain problems with the ECU limitations.
These are avoidable with external electronics such as an S-AFC or other piggyback device, so long as you know how to tune it correctly.
Unlike you folks across the ocean, all the North American Tiburons and Elantras up to 2001 were MAF-based, instead of the more common MAP. By using a MAF, or mass air flow sensor, the computer can actually measure the exact mass of the incoming air and make fuel adjustments accordingly. When using a MAP, or manifold absolute pressure sensor, you can only look at general intake pressure instead of total airflow.
Why is this important?
Let's say you have a 100% stock Tiburon, but the computer delivers fuel based on a MAP system. When you put your foot on the floor, the MAP sensor reads zero vacuum. The computer knows that a stock engine at zero vacuum needs 200cc/min of fuel (for example). Now you bolt on an intake, a bigger throttle body, a new manifold, a set of wild cams, a header and a full exhaust system. You apply full throttle, and the MAP sensor will report zero vacuum again. Guess what? The computer cannot see anything that you changed, so it assumes that zero vacuum = 200cc/min of fuel. The engine goes lean, problems ensue...
A MAF sensor doesn't exhibit this problem. A fully stock Tiburon with your foot on the floor may register 12.8lbs/min of air coming in thru the MAF sensor, so the onboard computer sends 200cc/min of fuel (as an example again). But you bolt-on all those parts I listed above, and now pressing your foot to the floor makes the MAF sensor register 16.2lbs/min of air coming in. The computer sees the increase, and accordingly adjusts fuel delivery to 240cc/min instead.
No lean condition, no bog, car works as you would expect it to.
Tuning a MAF-based car is a significantly different exercise than a MAP-based car. This is why (I believe) Alpine is having so many problems with getting their turbocharger and supercharger kits really well tuned in the North American market -- because they are still wanting to treat it like a MAP system.
The MAF sensor on the Tiburon/Elantra BETA engines is good to at least 240 wheel horsepower; it may even be higher. The only real problem is that the stock ECU was never meant to accept such a high signal from the MAF (no stock engine would ever move that much air, so the ECU thinks it's an error) and as such you run into certain problems with the ECU limitations.
These are avoidable with external electronics such as an S-AFC or other piggyback device, so long as you know how to tune it correctly.
11-13-2002 | 03:02 AM
#18
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Joined: Mar 2002
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All depends on how you break you car in... smile.gif
http://www.mototuneusa.com/break_in_secrets.htm
Least according to him.
-Steve
http://www.mototuneusa.com/break_in_secrets.htm
Least according to him.
-Steve
11-13-2002 | 03:22 AM
#19
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He's probably not far off, but I still wouldn't recommend running a brand new engine to it's full RPM band within 20 miles of it being new. I DO recommend planting your foot on the floor more than a few times, but stopping at the normal break-in RPM limits.
What he is saying holds partial truth in how the rings will react, depending on the materials used. What he is missing or downplaying is that you can cause damage to a motor by spinning it too fast right when it's new. Things do loosen up over time, mostly bearing clearances and piston-to-wall interaction.
FLooring the car allows you to build the full amount of combustion pressure when the plug fires, which does indeed force the rings into the cylinder walls and will make them seal tighter. But RPM's aren't what do it, and RPM's shouldn't be promoted as such.
My new motor was broken in at normal RPM incrememnts over 1000 miles, but was given full throttle on MANY occasions, even within the first few miles it was driven. And I did indeed change my oil within about 30 miles of first starting it, because it did have quite a few little metal pieces in it.
He's got the right idea, just ignore anything to do with using all RPM's that early on a brand new motor.
What he is saying holds partial truth in how the rings will react, depending on the materials used. What he is missing or downplaying is that you can cause damage to a motor by spinning it too fast right when it's new. Things do loosen up over time, mostly bearing clearances and piston-to-wall interaction.
FLooring the car allows you to build the full amount of combustion pressure when the plug fires, which does indeed force the rings into the cylinder walls and will make them seal tighter. But RPM's aren't what do it, and RPM's shouldn't be promoted as such.
My new motor was broken in at normal RPM incrememnts over 1000 miles, but was given full throttle on MANY occasions, even within the first few miles it was driven. And I did indeed change my oil within about 30 miles of first starting it, because it did have quite a few little metal pieces in it.
He's got the right idea, just ignore anything to do with using all RPM's that early on a brand new motor.
