Power Adders (FI) For Dummies (Turbo, Supercharger, Nitrous)
11-11-2007, 06:11 AM
#51
Agreed - but also Know Thyself.
If you tend to be more aggressive than most when it comes to modding; find a shop who is more conservative and vice versa. It never hurts to have a devils advocate. The downside being the point made by Rumboo; lack of exp. But hopefully a happy medium can be found.
If you tend to be more aggressive than most when it comes to modding; find a shop who is more conservative and vice versa. It never hurts to have a devils advocate. The downside being the point made by Rumboo; lack of exp. But hopefully a happy medium can be found.
01-04-2008, 09:33 PM
#55
82 RX-7 GSL
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Rotary Fragility with Detonation
Understanding the "fragility" of a rotary motor as compared to a piston motor is not a simple exercise. Though the inertial loading on the rods of a piston motor are extreme, the dynamics are known and very simple. Piston design is at a state where there are very few variables left to consider.
A rotary motor is under considerably more stress and that stress is highly dynamic, principally because of the engine's simplicity. Think about what an apex seal is being asked to do: it must support two phases of combustion simultaneously on opposite sides while constantly accelerating (and decelerating) along two axes of motion!
Though there are no rods to stress, detonation affects the dynamics of the rotary motor with forces that are exponentially more damaging than they are in a piston motor. (BTW - detonation is not pre-ignition and understanding the difference is pretty important.) The Renesis is FAR more fragile than any other motor in existence. It cannot take ANY overheating. It cannot survive any pre-ignition. It will not survive any oiling malfunctions. Though it might keep running, any failings in the fuel/water/oil will yield a damaged motor. A piston motor's typical failure mode will lower its operational efficiency by some fraction of its total output. A rotary motor - even with a minor failure - typically becomes completely unusable. Similarly, a Renesis is not really rebuildable after a failure. Under optimal conditions however, the Renesis may be the most robust motor in existence because of its simplicity.
Understanding the "fragility" of a rotary motor as compared to a piston motor is not a simple exercise. Though the inertial loading on the rods of a piston motor are extreme, the dynamics are known and very simple. Piston design is at a state where there are very few variables left to consider.
A rotary motor is under considerably more stress and that stress is highly dynamic, principally because of the engine's simplicity. Think about what an apex seal is being asked to do: it must support two phases of combustion simultaneously on opposite sides while constantly accelerating (and decelerating) along two axes of motion!
Though there are no rods to stress, detonation affects the dynamics of the rotary motor with forces that are exponentially more damaging than they are in a piston motor. (BTW - detonation is not pre-ignition and understanding the difference is pretty important.) The Renesis is FAR more fragile than any other motor in existence. It cannot take ANY overheating. It cannot survive any pre-ignition. It will not survive any oiling malfunctions. Though it might keep running, any failings in the fuel/water/oil will yield a damaged motor. A piston motor's typical failure mode will lower its operational efficiency by some fraction of its total output. A rotary motor - even with a minor failure - typically becomes completely unusable. Similarly, a Renesis is not really rebuildable after a failure. Under optimal conditions however, the Renesis may be the most robust motor in existence because of its simplicity.
The engine is also certainly rebuildable. Guys have been doing it at home with kits for years on the 12A and various 13B's. The 13B MSP is just the latest variant.
Piston engines that aren't reinforced tend to have problems with boost as well. They also have to have parts replaced when they blow, same as rotaries.
Don't sell these engines so short.
01-06-2008, 04:30 PM
#56
The engine is also certainly rebuildable. Guys have been doing it at home with kits for years on the 12A and various 13B's. The 13B MSP is just the latest variant.
Piston engines that aren't reinforced tend to have problems with boost as well. They also have to have parts replaced when they blow, same as rotaries.
Don't sell these engines so short.
Piston engines that aren't reinforced tend to have problems with boost as well. They also have to have parts replaced when they blow, same as rotaries.
Don't sell these engines so short.
03-06-2008, 02:15 PM
#57
the bukkake master!
didnt really know where to post this question so here looked like a good spot. ok well in regards to a turbo how is it that by different tuning, the turbo is able to change how much boost it is providing? like how do you get the turbo to change how much air it is pushing into the engine by tuning. are you somehow increasing exhaust output so that the turbine is spinning more? i know i'm wording it wrong and it probably sounds like a retarded question but i'm just trying to learn so please be gentle 
03-06-2008, 02:43 PM
#58
didnt really know where to post this question so here looked like a good spot. ok well in regards to a turbo how is it that by different tuning, the turbo is able to change how much boost it is providing? like how do you get the turbo to change how much air it is pushing into the engine by tuning. are you somehow increasing exhaust output so that the turbine is spinning more? i know i'm wording it wrong and it probably sounds like a retarded question but i'm just trying to learn so please be gentle
The wastegate has a spring that is connected to a pressurized vacuum hose. the pressure opens up the wastegate. So if the spring is rated for 7 psi, it'll start to open up at 4 psi a bit, and by 7 psi it'll be all the way open.
A boost controller can be used too, which sits between the wastegate and the boost signal. All it does is tell the wastegate that there is less psi than there actually is, which keeps the wastegate shut longer, causing boost to build more rapidly. If you wanted more psi, you just tell the boost controller, and it will hold off on telling the wastegate about the pressure till the desired pressure is reached.
03-06-2008, 03:00 PM
#59
the bukkake master!
The turbo has a wastegate. It's basically a turbo bypass. When open, exhaust can flow around the turbo blades, causing the turbo to no longer spool up any higher. This is important or your engine will blow up.
The wastegate has a spring that is connected to a pressurized vacuum hose. the pressure opens up the wastegate. So if the spring is rated for 7 psi, it'll start to open up at 4 psi a bit, and by 7 psi it'll be all the way open.
A boost controller can be used too, which sits between the wastegate and the boost signal. All it does is tell the wastegate that there is less psi than there actually is, which keeps the wastegate shut longer, causing boost to build more rapidly. If you wanted more psi, you just tell the boost controller, and it will hold off on telling the wastegate about the pressure till the desired pressure is reached.
The wastegate has a spring that is connected to a pressurized vacuum hose. the pressure opens up the wastegate. So if the spring is rated for 7 psi, it'll start to open up at 4 psi a bit, and by 7 psi it'll be all the way open.
A boost controller can be used too, which sits between the wastegate and the boost signal. All it does is tell the wastegate that there is less psi than there actually is, which keeps the wastegate shut longer, causing boost to build more rapidly. If you wanted more psi, you just tell the boost controller, and it will hold off on telling the wastegate about the pressure till the desired pressure is reached.
03-06-2008, 03:02 PM
#60
The Professor
To not make boost the gate opens slightly to let the gas exit out the exhaust. This causes the turbo to slow down because nothing is pushing it.
03-06-2008, 03:04 PM
#61
The Professor
check my thread, the first post has pictures of the turbo, the big purple thing is the wastegate. https://www.rx8club.com/series-i-major-horsepower-upgrades-93/esmeril-turbo-kit-review-pics-138414/
03-06-2008, 03:12 PM
#62
Like I said, it's the wastegate actuator (spring) that determines how much boost the turbo will reach. A boost controller gives you even more control.
Not all turbos are alike, there are many variations, and configurations.
Also boost is not just boost. You have to consider flow rates too. For example, 9 psi on the greddy turbo is a lot less powerful than 9 psi on the mazdamaniac turbo.
i miss read your post mysql. thanks to both of you for helping me out!
03-15-2008, 07:59 PM
#67
Registered
You are looking for an Oxygen candle.
Oxygen Candle
Wikipedia entry
The candle is Iron and Sodium Chlorate, burns very hot though, 600 degrees C.
There is a Russian version that burns at a lower temp.
03-16-2008, 09:55 PM
#69
Registered
fuel efficiency?
I have a question, I've been reading from different sources for fuel efficiency.
I have seen reports that adding a charger, turbo or super would increase fuel effiency. But i've also heard that adding such devices to increase engine power decreases fuel effiency. I'm guessing there's two type of Fuel Effiency being talked about, but I haven't read 1 source that has both types (if both exist) listed.
I'm interested in getting the highest MPG out of an RX8 as possible and if there's any aftermarket items that would increase the MPG to a more tollerable number - like a low 30s. I don't care about engine power, Im not racing and I don't have any interest in showing off. I'd rather leave a couple minutes eariler and ride without a care, then stress and zoom for that hot flash that'll come over me when I see a parked police car. Thankfully the car must've not noticed me >.>
I have seen reports that adding a charger, turbo or super would increase fuel effiency. But i've also heard that adding such devices to increase engine power decreases fuel effiency. I'm guessing there's two type of Fuel Effiency being talked about, but I haven't read 1 source that has both types (if both exist) listed.
I'm interested in getting the highest MPG out of an RX8 as possible and if there's any aftermarket items that would increase the MPG to a more tollerable number - like a low 30s. I don't care about engine power, Im not racing and I don't have any interest in showing off. I'd rather leave a couple minutes eariler and ride without a care, then stress and zoom for that hot flash that'll come over me when I see a parked police car. Thankfully the car must've not noticed me >.>
Mazmart has a 3.9 and a 4.1 ratio gear set for sale to replace the stock 4.44.
04-06-2008, 11:05 PM
#72
Registered
electric Supercharger
Thought I would share this. Hadn't seen anything like this since the RX-8 hydrogen protoype.
http://www.autocar.co.uk/News/NewsAr...-Elise/232017/
Would be interesting to see this applied to an 8 when it hits production.
http://www.autocar.co.uk/News/NewsAr...-Elise/232017/
Would be interesting to see this applied to an 8 when it hits production.
04-07-2008, 01:16 AM
#73
Thought I would share this. Hadn't seen anything like this since the RX-8 hydrogen protoype.
http://www.autocar.co.uk/News/NewsAr...-Elise/232017/
Would be interesting to see this applied to an 8 when it hits production.
http://www.autocar.co.uk/News/NewsAr...-Elise/232017/
Would be interesting to see this applied to an 8 when it hits production.
04-08-2008, 12:04 AM
#75
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Thought I would share this. Hadn't seen anything like this since the RX-8 hydrogen protoype.
http://www.autocar.co.uk/News/NewsAr...-Elise/232017/
Would be interesting to see this applied to an 8 when it hits production.
http://www.autocar.co.uk/News/NewsAr...-Elise/232017/
Would be interesting to see this applied to an 8 when it hits production.
Last edited by MPG > HP; 04-08-2008 at 12:07 AM.