If SOHC VTEC is made for eonomy, then why...
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The exhaust on the EX is different than that of an LX/DX.
The compression is also higher on an EX, than it is on the LX/DX.
So if you have converted your car to EX specs, than how much power are you putting down to the wheels? Got a dyno? Probably not.
The compression is also higher on an EX, than it is on the LX/DX.
So if you have converted your car to EX specs, than how much power are you putting down to the wheels? Got a dyno? Probably not.
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From: so cal djmota=oscar
Rep Power: 324 Originally posted by thecheat
anybody got a valve lift spec for the vtec and normal cams in a D17A2? how about the ones from a non-VTEC D series. I bet you will find a differance there
anybody got a valve lift spec for the vtec and normal cams in a D17A2? how about the ones from a non-VTEC D series. I bet you will find a differance there
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Originally posted by redvtec04
Nope. compression and exhaust are the same. I have one of each.
Nope. compression and exhaust are the same. I have one of each.
EX 9.9:1
LX/DX 9.5:1
The cam lift is different, obvioiusly the extra lift and the timing advance adds to it as well
The D17A1 close coupled cat is like a cork, its more restrictive on the engine and it keeps all the heat in the engine bay. This helps the catalyst, but it doesn't help the power.
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Rep Power: 0 It seems that Dx/Lx's have are a little more responsive in the lower ranges. My g/f has the Lx and it feels totally different than my Ex. I'd be willing to wager that it's because of the exhaust tho cuz after 4k the Ex puts down a noticeable difference
yeah I have an LX and my wife had an EX..I defenietly had more pull in the lower end,and she had more once she reached the VTEC point.But my guess would be that the EX's HP numbers are higher mainly because of the higher compression.
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Rep Power: 0 I'd guess the reason the LX feels a tad more responsive is the lack of VTEC, and the subsequent higher low-end torque/horsepower.
Our engines are cheepo VTEC instead of full-blown VTEC. Our VTEC dosen't manipulate the exhaust valve distances.
It's my thoughts that they are made for performance, but they are not make to be the epitomy of performance, e.g. K series.
90% of all racing comes down to the driver. I say 90% because, IMO, most drivers won't get into a race they know are gonna lose (Mustang Cobra vs. Vic DX type stuff). If you're good in a DX, you'll wipe the floor with a bad EX driver. Even moreso if he's got an automatic and you've got a manual.
Our engines are cheepo VTEC instead of full-blown VTEC. Our VTEC dosen't manipulate the exhaust valve distances.
It's my thoughts that they are made for performance, but they are not make to be the epitomy of performance, e.g. K series.
90% of all racing comes down to the driver. I say 90% because, IMO, most drivers won't get into a race they know are gonna lose (Mustang Cobra vs. Vic DX type stuff). If you're good in a DX, you'll wipe the floor with a bad EX driver. Even moreso if he's got an automatic and you've got a manual.
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Rep Power: 0 All of you missed a huge reason...THE TRANSMISSIONS ARE DIFFERENT...The EX transmissions are geared different than the others. And believe me, this makes a HUGE difference.
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From: chantilly, Virginia, US
Rep Power: 338 Originally posted by bobbyd
All of you missed a huge reason...THE TRANSMISSIONS ARE DIFFERENT...The EX transmissions are geared different than the others. And believe me, this makes a HUGE difference.
All of you missed a huge reason...THE TRANSMISSIONS ARE DIFFERENT...The EX transmissions are geared different than the others. And believe me, this makes a HUGE difference.
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Rep Power: 0 Originally posted by cambo
If you want to be technical, and i do want to be technical, the transmission has nothing to do with horsepower. It does affect accelertion and top speed though.
If you want to be technical, and i do want to be technical, the transmission has nothing to do with horsepower. It does affect accelertion and top speed though.
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Rep Power: 0 uh.....
The S2000 is a VTEC engine.
It makes 109 horsepower per litre, naturally aspirated.
On top of that, look at it this way.
A proper valvetrain allows for complete stratification of the intake charge before ignition. Larger valve openings at lower RPM's don't maintain high enough intake air speed across the valve opening. High speed across the valve is essential for stratification. A stratified charge burns more througly, using more of it's energy to drive your butt down the road. At higher RPM, the valve opening can be larger due to higher air need. Therefore using VTEC, the fuel charge can be burned more efficiently at any RPM. Efficient combustion makes for more power gained per unit of fuel burned. The S2000 burns a nice bit of fuel.
Name another factory engine that makes 100+ horsepower/litre without forced induction whlile being below 50 large to park in the driveway.
The S2000 is a VTEC engine.
It makes 109 horsepower per litre, naturally aspirated.
On top of that, look at it this way.
A proper valvetrain allows for complete stratification of the intake charge before ignition. Larger valve openings at lower RPM's don't maintain high enough intake air speed across the valve opening. High speed across the valve is essential for stratification. A stratified charge burns more througly, using more of it's energy to drive your butt down the road. At higher RPM, the valve opening can be larger due to higher air need. Therefore using VTEC, the fuel charge can be burned more efficiently at any RPM. Efficient combustion makes for more power gained per unit of fuel burned. The S2000 burns a nice bit of fuel.
Name another factory engine that makes 100+ horsepower/litre without forced induction whlile being below 50 large to park in the driveway.
Originally posted by ati9700pro
ex is obviously faster, they wouldnt charge more if it wasnt faster.
ex is obviously faster, they wouldnt charge more if it wasnt faster.
Anyway, VTEC is all about getting the right lift and timing at the right RPM and intake charge speed. The Ex is faster because they spend a little more on the motor and put a better cat and pipe in it. But remember that we are talking about fractional differances and the other models weigh less. So yes, SOHC vetec is for more power but thats not all they do to make it faster, thats just the part they advertise. Honda pushes VTEC in the D series cars to add to their image and sell the technological advantage of their products. Just look at what all the other makers have started doing, they all have cool names for their engines now, just like honda. Its all about selling cars, and the benifit is that we get some cool stuff along the way. Not even thirty years ago, anything like VTEC was purely race car stuff or so expensive to make that it didnt see production. Now this kind of technology is available on all sorts of things.
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Rep Power: 382 All Vtec is for economy. Thats the point, to have an economic engine when just putting around and then having a "High" performance engine when you push it.
Look at the Pro Drag cars, they dont run Vtec!! they just run the High cam.
Look at the Pro Drag cars, they dont run Vtec!! they just run the High cam.
Originally posted by ati9700pro
ex is obviously faster, they wouldnt charge more if it wasnt faster.
ex is obviously faster, they wouldnt charge more if it wasnt faster.
the ex is faster but not faster to the point to determine the result of a race to a lx/dx. and yes they would charge more because of the alloys it comes with (i think) and the sun roof and the painted side mirrors and matching doorhandles. it also comes with an extra cat underneith the car. a race between a lx/dx and a ex is driver. period
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From: chantilly, Virginia, US
Rep Power: 338 Originally posted by Chompondis
it also comes with an extra cat underneith the car. a race between a lx/dx and a ex is driver. period
it also comes with an extra cat underneith the car. a race between a lx/dx and a ex is driver. period
moved the car further down as well as making a better flowing header = yes.
