No torque??
12-16-07, 09:11 PM
#29
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12-16-07, 10:58 PM
#30
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I know that keeping his 5th and 6th port open wont help with low end torque. But if the cylinder in the intake mainfold is blocking the runners for the 5th and 6th port, then the ports are not being used. If his air pump is off, then the runners are definetly closed because the spring holds the lever to the cylinder until enough air can open it. If I had pictures, youll see exactly what im talking about.
Im saying this because i had almost the same setup as you but my streetport was very small. Your car should be faster than mind but by the looks of your 1/4 mile mph, you are slower. If you can pull on an 06 rsx type-s on the highway, than you are very close to where you should be at.
This is all from my experience. Besides, a stock rx7 should make that kind of power with an intake and exhaust if everything is working properly. Your only making about 15 more hp from stock.
Its easy to do and it wont mess up anything. On the right side of the intake, you'll see a tiny E-clip holding a rod to the lever. Pull off the clip, release the rod and you will be able to pull the lever down. I garantee you if this lever was up the whole time, your gonna notice a difference in power and you will get more torque, but not at the bottom end.
Im saying this because i had almost the same setup as you but my streetport was very small. Your car should be faster than mind but by the looks of your 1/4 mile mph, you are slower. If you can pull on an 06 rsx type-s on the highway, than you are very close to where you should be at.
This is all from my experience. Besides, a stock rx7 should make that kind of power with an intake and exhaust if everything is working properly. Your only making about 15 more hp from stock.
Its easy to do and it wont mess up anything. On the right side of the intake, you'll see a tiny E-clip holding a rod to the lever. Pull off the clip, release the rod and you will be able to pull the lever down. I garantee you if this lever was up the whole time, your gonna notice a difference in power and you will get more torque, but not at the bottom end.
What was your 1/4 mile mph, and what were your mods? Don't forget, my car is completely stock except for the port and flywheel. I've never been up against an RSX, and it probably won't happen anytime soon. There are a lot of ricers in my area, but unfortunately I've never had a chance to race anybody. (Except for this one time I pulled up next to a C5 Z06. Needless to say, it wasn't much of a race.)
In my opinion, having the inserts is not worth the risk of them fall out and getting clipped by a rotor, so I don't think I will be installing them. Any other suggestions besides exhaust and Rtek?
On a side note, I don't think it will be possible to get SDJ headers anytime soon. Banzaitoyota said that raw materials have quadrupled in price, and he doesn't think there will be a market for them with the raised price. I suggested a group buy thread, but if that doesn't happen what are my other options? Corksport? I want to aviod Racing Beat because of the weight.
12-17-07, 01:28 AM
#31
What im saying is your ports can be open and no flow will get to them if the intake runners are closed. Just check and see if that lever on the right side of the intake is even moving because its supposed to. It has nothing to do with the actuators. My car made more power after i did this even though my actuators were eliminated and the sleeves were removed.
12-17-07, 07:24 AM
#32
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I know that keeping his 5th and 6th port open wont help with low end torque. But if the cylinder in the intake mainfold is blocking the runners for the 5th and 6th port, then the ports are not being used. If his air pump is off, then the runners are definetly closed because the spring holds the lever to the cylinder until enough air can open it. If I had pictures, youll see exactly what im talking about.
The VDI does not block the secondary runners by any means. Look in the factory service manual for VDI and you will see what it does.
Its only open somewhere above 5000 to allow the pressure wave created from the closing ports in one rotor to bounce over to the other side of the engine. The S4 manifold does this to except the timing is far greater so the compression wave is weakend by the time it travels to the other side. The Aux port sleeves only close the aux ports not the secondary runners.
12-17-07, 07:34 AM
#33
That's the thing, Pineapple never released any dyno testing proof regarding this sleeves, or at least I've never seen it. They pretty much said, "It adds power, take my word for it." Sorry, but that's not good enough for me since these days, even if intuition says it will work, a lot of times, you end up with unexpected, i.e. negative results.
12-17-07, 07:38 AM
#34
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I bet trying to measure the extra power that may be created by using the sleeves will almost be impossible to measure unless you do it back to back at the same IAT. Going home, putting the sleeves in and going back a few days later when it may be warmer or colder out, may not show the extra power created by the sleeves.
I heard 5hp is what they could give you, maybe in a perfect world, I dunno.
I can't see the sleeves making negitive effects when your smoothing out the airflow .
I heard 5hp is what they could give you, maybe in a perfect world, I dunno.
I can't see the sleeves making negitive effects when your smoothing out the airflow .
12-17-07, 09:29 AM
#35
Are you really smoothing out the airflow though? I'm not sure exactly what my friend said, but he's a mech eng student and he thought that the sleeves would create turbulence in a certain spot in the runners....I'll have to ask him to repeat what he said specifically.
12-17-07, 09:44 AM
#36
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Your smoothing out the airflow at the port opening. I Don't know how much of an effect it will have through the entire runner. I don't know much in this area. But the theory is right.
12-19-07, 01:54 AM
#38
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The inserts just help to more smoothly transition from the end of the sleeve to the combustion chamber. Without them the air slams into the end of the runner and then is forced out at a 90* angle to the face of the port. Its effect is like smoothing the port transition in the primary or secondary ports.
The 'cylinder thing' rotor keeps refering to is the VDI. If that wasn't working your HP would drop off significantly after about 6000 rpms. When your engine sweeps past 5200 that is the kick in power that you feel. the cylinder spins in the manifold and opens a shorter runner for the secondaries. It also sets up the runners to face each other and feed off the positive pressure that occurs when a rotor closes the port and the air in the intake runner backs up. the pressure wave from that event feeds back up the intake runner and then down the other runner and compresses the air in that runner just as its port is opening. This helps to force more air into the combustion chamber and helps increase port velocity. I have read somewhere that the positive pressure can reach as much as 2 psi in the intake runner as the port opens. Its essentailly free supercharging and Mazda even refers to it as a 'supercharging effect.'
BC
The 'cylinder thing' rotor keeps refering to is the VDI. If that wasn't working your HP would drop off significantly after about 6000 rpms. When your engine sweeps past 5200 that is the kick in power that you feel. the cylinder spins in the manifold and opens a shorter runner for the secondaries. It also sets up the runners to face each other and feed off the positive pressure that occurs when a rotor closes the port and the air in the intake runner backs up. the pressure wave from that event feeds back up the intake runner and then down the other runner and compresses the air in that runner just as its port is opening. This helps to force more air into the combustion chamber and helps increase port velocity. I have read somewhere that the positive pressure can reach as much as 2 psi in the intake runner as the port opens. Its essentailly free supercharging and Mazda even refers to it as a 'supercharging effect.'
BC
12-19-07, 08:28 AM
#39
My only point is that even if the theory holds out, once empirical proof sets in, then you have a valid basis. Right now, all we're doing is guessing.
Case in point:
What's the most important aspect of power in any engine? Airflow, since fuel and spark can both be easily added. Now, divide airflow up into intake and exhaust, and we all know, for rotaries, exhaust tuning is more critical than intake tuning.
Focusing on exhaust, who makes the headers that have made the most power on stock engines? Speedsource. They've made both a long primary and a short primary exhaust. From what I've heard, the long primary is supposed to make more power than the short primary, due to the greater (albeit diminishing) returns from exhaust scavenging. On the dyno, however, both systems dyno withing 1-2 hp of each other. Theory says that the long primary should make more power, especially since they're both designed for stock motors. (Both exhausts were developed mainly for IT racing, which requires stock engine)
The only thing that concerns me is that Pineapple never released dyno data, unlike other companies, such as Racing Beat. (Although their turboback data........) Without it, who can say for sure? Butt dyno? Intuition? I'd rather not waste my money on guesstimates.
For race cars anyway (ones that see no street duty, not cars that people think are "race cars"), the best way to make power is to remove those sleeves completely.
Case in point:
What's the most important aspect of power in any engine? Airflow, since fuel and spark can both be easily added. Now, divide airflow up into intake and exhaust, and we all know, for rotaries, exhaust tuning is more critical than intake tuning.
Focusing on exhaust, who makes the headers that have made the most power on stock engines? Speedsource. They've made both a long primary and a short primary exhaust. From what I've heard, the long primary is supposed to make more power than the short primary, due to the greater (albeit diminishing) returns from exhaust scavenging. On the dyno, however, both systems dyno withing 1-2 hp of each other. Theory says that the long primary should make more power, especially since they're both designed for stock motors. (Both exhausts were developed mainly for IT racing, which requires stock engine)
The only thing that concerns me is that Pineapple never released dyno data, unlike other companies, such as Racing Beat. (Although their turboback data........) Without it, who can say for sure? Butt dyno? Intuition? I'd rather not waste my money on guesstimates.
For race cars anyway (ones that see no street duty, not cars that people think are "race cars"), the best way to make power is to remove those sleeves completely.
12-19-07, 10:28 AM
#40
When people say its gained 1/2hp or things like that ... usually speaking peak HP, which would probably true, but when you at the line also being shifted up from say 3500rpm on, the area under the graph would be more increased. Its all about where you want your power. You can't just look at peak power figures. And also about the long/short primaries, it would effect more the torque curve than anything. You can't just look at one variable and call it a day. Laying both graphs ontop of each other is the best thing to do.
Also the other things that you have to look at is throttle response. ITB compared to single butterfly for single engine. Being able to shave off say 1 second off your 0-60mph (not using any actual figures just stating), on the track mean being able to reach your max Redline faster being able to use up all your HP faster, and in simple terms, over taking another guy faster and maybe winning the race.
I had always wished they had a Time (in milliseconds or so) to show you how long the duration from 1.5k rpm - 9k rpm takes.
Also the other things that you have to look at is throttle response. ITB compared to single butterfly for single engine. Being able to shave off say 1 second off your 0-60mph (not using any actual figures just stating), on the track mean being able to reach your max Redline faster being able to use up all your HP faster, and in simple terms, over taking another guy faster and maybe winning the race.
I had always wished they had a Time (in milliseconds or so) to show you how long the duration from 1.5k rpm - 9k rpm takes.
12-19-07, 12:27 PM
#42
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You can increase torque output by swapping your final drive ratio to something more aggressive.
Shameless self promotion of me selling my 4.44 ring and pinion:
https://www.rx7club.com/showthread.php?t=714046
Shameless self promotion of me selling my 4.44 ring and pinion:
https://www.rx7club.com/showthread.php?t=714046
12-19-07, 01:32 PM
#44
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Dynos measure power output of the engine. reguardless of what gears you put between the dyno and the engine the power is going to be the same. Frankly it doesn't matter what gear you dyno in if you are doing a power pull. All that stuff about 1:1 pulls is just superstition started by people who don't understand the science behind the dyno.
The only difference that you would see on a dyno in regaurds to gears is on a power vs. road speed graph, where you could see gearing advantages/disadvantages.
12-19-07, 01:34 PM
#45
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Think of it this way, when you press the pedal in 1st gear, doesn't it accelerate faster than if you pushed the pedal down in 5th gear?
Yes there is a difference, but it doesn't change the fact that at 2K rpms your car is making the same amount of power reguardless of what gear its in or what wheels are on it.
Yes there is a difference, but it doesn't change the fact that at 2K rpms your car is making the same amount of power reguardless of what gear its in or what wheels are on it.
12-19-07, 02:38 PM
#46
However, dynos measure torque and then calculate power. So while my engine makes x hp at y rpm no matter what gear it's in, since the dyno sees ft-lbs, and gears act as torque multipliers, a Dyno would need some sort of gear reference to properly scale power, otherwise, you'd see multiples.
Unless of course, I have it wrong, and dynos measure power and calculate torque......
Unless of course, I have it wrong, and dynos measure power and calculate torque......
12-19-07, 04:15 PM
#47
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If this helps at all, in my dyno thread the first dyno video read something like 1700 hp. Not sure what they did, but they screwed up somehow. They guy asked me if I had an upgraded clutch because that can sometimes mess with it. This is coming from the same guy who insisted that I only dyno to7.5k because he didn't want it to blow it up (even though it clearly shows an 8k redline), so I don't know how well he knows this stuff, but maybe that information can be of some use.
On a different topic (not really, but whatever) I gained some torque back. I had a leak between my downipe/precat flanges and another on the first flange of the main cat. I got the whole pipe replaced (he took off the precat) and the car definitely has noticeably more torque between 1000-3500 rpm. The rest still feels the same, which doesn't really help my 115 ft/lb situation, but I guess it's a start.
On a different topic (not really, but whatever) I gained some torque back. I had a leak between my downipe/precat flanges and another on the first flange of the main cat. I got the whole pipe replaced (he took off the precat) and the car definitely has noticeably more torque between 1000-3500 rpm. The rest still feels the same, which doesn't really help my 115 ft/lb situation, but I guess it's a start.
12-19-07, 04:53 PM
#49
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The dyno reads the RPM from the spark plug wire and the RPMs at the rollers and compare them. It then can tell what the gearing between the engine and the rollers is, and compensate for it when finding torque and hp. Thats why it technically doesnt matter what gear you dyno in.
The reason it read 1700 hp is likely because the dyno wasn't getting a good engine RPM signal so it didn't know how to compensate the torque numbers it was getting. So it was a ridiculous tq number being added into the equation.
BC
The reason it read 1700 hp is likely because the dyno wasn't getting a good engine RPM signal so it didn't know how to compensate the torque numbers it was getting. So it was a ridiculous tq number being added into the equation.
BC