Compound boost: EFR 7670 into Coldside FFS W/ H20/Meth into 10.5:1 VVT Built Engine
#21
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sounds like it will also create a metric fuckton of heat in the process...
I am impressed that you were able to get the EFR to fit in the engine bay with that log manifold. This just doesn't seem like a very efficient way of creating an awesome power curve though. I have a feeling that the supercharger will end up restricting flow at the top end and just turn it into excess charge air temp. If you wanted to twincharge this thing, wouldn't a compound turbo setup be cheaper and more efficient? Or possibly split the intake charges so that the supercharger feeds the engine until a certain turbine speed is met and let the turbo have it's flow routed past the S/C? After all, that is why we love turbos more than superchargers. The are able to create pressurized air at high flow rates in an efficient manner.
I am impressed that you were able to get the EFR to fit in the engine bay with that log manifold. This just doesn't seem like a very efficient way of creating an awesome power curve though. I have a feeling that the supercharger will end up restricting flow at the top end and just turn it into excess charge air temp. If you wanted to twincharge this thing, wouldn't a compound turbo setup be cheaper and more efficient? Or possibly split the intake charges so that the supercharger feeds the engine until a certain turbine speed is met and let the turbo have it's flow routed past the S/C? After all, that is why we love turbos more than superchargers. The are able to create pressurized air at high flow rates in an efficient manner.
#22
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Yeah I get that, I guess I was just looking at it as what happens when one is out performing the other? will the less performing charger not create a drag reducing the performance of each system if it was running independently? Or is that negligible due to the performance gain? So even a supercharger running at half of its normal efficiency due to the turbo creating drag at low rpms would still be better than no supercharger at all I guess. Or will the supercharger suction just cause the turbo to spool up faster and not really allow much drag from the turbo?
Just thinking out loud here
Either way im excited to see what happens.
Just thinking out loud here
Either way im excited to see what happens.
That's just my take on it. There are much much more in depth explanations to this should you wish to pursue the science of it, but the end result should be pretty promising.
sounds like it will also create a metric fuckton of heat in the process...
I am impressed that you were able to get the EFR to fit in the engine bay with that log manifold. This just doesn't seem like a very efficient way of creating an awesome power curve though. I have a feeling that the supercharger will end up restricting flow at the top end and just turn it into excess charge air temp. If you wanted to twincharge this thing, wouldn't a compound turbo setup be cheaper and more efficient? Or possibly split the intake charges so that the supercharger feeds the engine until a certain turbine speed is met and let the turbo have it's flow routed past the S/C? After all, that is why we love turbos more than superchargers. The are able to create pressurized air at high flow rates in an efficient manner.
I am impressed that you were able to get the EFR to fit in the engine bay with that log manifold. This just doesn't seem like a very efficient way of creating an awesome power curve though. I have a feeling that the supercharger will end up restricting flow at the top end and just turn it into excess charge air temp. If you wanted to twincharge this thing, wouldn't a compound turbo setup be cheaper and more efficient? Or possibly split the intake charges so that the supercharger feeds the engine until a certain turbine speed is met and let the turbo have it's flow routed past the S/C? After all, that is why we love turbos more than superchargers. The are able to create pressurized air at high flow rates in an efficient manner.
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I mean he's already going through with it. Its not like you dissing the setup is going to make him part everything out and start over.
The only thing that would do that is if the setup ends up not working like he's hoping.
And that we shall see.
IF it works though, its going to be crazy.
#23
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what is your goal for this? Are you trying to just create a cool proof of concept? Or are you shooting for a specific performance gain (700hp for example).
Most people who have tried for high power builds focus a lot more of their energy on overall flow capability of the entire system rather than just building more boost. I am not saying that you should not do this or anything. (it is pretty freaking cool after all) This is just not the way big power is made and you will be subject to mass amounts of trolling.
Most people who have tried for high power builds focus a lot more of their energy on overall flow capability of the entire system rather than just building more boost. I am not saying that you should not do this or anything. (it is pretty freaking cool after all) This is just not the way big power is made and you will be subject to mass amounts of trolling.
#27
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Lol at complaining to be laggy with a log manifold. You better not say you have a small exhaust as well.
Also what is up with your AIT being so high especially when the BW turbos are so much win? On my unhappy over spun m62 heatgun I see AIT of 100 after the IC. On my old volvo with an inefficient ebay turdblow and IC behind the ac condenser AIT below 120. Compound charging will just increase your AIT even more.
Also what is up with your AIT being so high especially when the BW turbos are so much win? On my unhappy over spun m62 heatgun I see AIT of 100 after the IC. On my old volvo with an inefficient ebay turdblow and IC behind the ac condenser AIT below 120. Compound charging will just increase your AIT even more.
#30
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Yeah I get that, I guess I was just looking at it as what happens when one is out performing the other? will the less performing charger not create a drag reducing the performance of each system if it was running independently? Or is that negligible due to the performance gain? So even a supercharger running at half of its normal efficiency due to the turbo creating drag at low rpms would still be better than no supercharger at all I guess. Or will the supercharger suction just cause the turbo to spool up faster and not really allow much drag from the turbo?
Just thinking out loud here
Either way im excited to see what happens.
Just thinking out loud here
Either way im excited to see what happens.
Where it really helps is the SC basically doubling the amount of air going through the engine. This will get more exhaust flowing through the turbine of the turbo, and spool it quicker. So I'll have the boost down low from the SC to get more torque down low, AND the turbo will spool quicker so I get more turbo power sooner.
I'm also excited to see what happens. I've never done this setup before, so don't know what to expect power wise and tuning wise. I more or less know how I'm hooking everything up, just don't know how well it's going to work. Stay tuned!
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sounds like it will also create a metric fuckton of heat in the process...
I am impressed that you were able to get the EFR to fit in the engine bay with that log manifold. This just doesn't seem like a very efficient way of creating an awesome power curve though. I have a feeling that the supercharger will end up restricting flow at the top end and just turn it into excess charge air temp. If you wanted to twincharge this thing, wouldn't a compound turbo setup be cheaper and more efficient? Or possibly split the intake charges so that the supercharger feeds the engine until a certain turbine speed is met and let the turbo have it's flow routed past the S/C? After all, that is why we love turbos more than superchargers. The are able to create pressurized air at high flow rates in an efficient manner.
I am impressed that you were able to get the EFR to fit in the engine bay with that log manifold. This just doesn't seem like a very efficient way of creating an awesome power curve though. I have a feeling that the supercharger will end up restricting flow at the top end and just turn it into excess charge air temp. If you wanted to twincharge this thing, wouldn't a compound turbo setup be cheaper and more efficient? Or possibly split the intake charges so that the supercharger feeds the engine until a certain turbine speed is met and let the turbo have it's flow routed past the S/C? After all, that is why we love turbos more than superchargers. The are able to create pressurized air at high flow rates in an efficient manner.
Compound turbo would require me completely redesigning my turbo setup, and forget A/C. SC bolts right up, now I don't need a new intake manifold, and will give me more torque down low and better throttle response than if I had a turbo instead. I'd still like to try a compound turbo setup on something, one day. Probably a diesel though.
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#32
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what is your goal for this? Are you trying to just create a cool proof of concept? Or are you shooting for a specific performance gain (700hp for example).
Most people who have tried for high power builds focus a lot more of their energy on overall flow capability of the entire system rather than just building more boost. I am not saying that you should not do this or anything. (it is pretty freaking cool after all) This is just not the way big power is made and you will be subject to mass amounts of trolling.
Most people who have tried for high power builds focus a lot more of their energy on overall flow capability of the entire system rather than just building more boost. I am not saying that you should not do this or anything. (it is pretty freaking cool after all) This is just not the way big power is made and you will be subject to mass amounts of trolling.
I dunno how this will work, I think it's gonna have a ton of low end torque and hit full boost by 5K with MUCH improved time to torque numbers. I think I might find the limit of stock 10:1 pistons. I might break the trans or diff or axles. I don't expect every person on an internet forum to approve of what I'm doing. I'll just keep doing it anyways.
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#33
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Lol at complaining to be laggy with a log manifold. You better not say you have a small exhaust as well.
Also what is up with your AIT being so high especially when the BW turbos are so much win? On my unhappy over spun m62 heatgun I see AIT of 100 after the IC. On my old volvo with an inefficient ebay turdblow and IC behind the ac condenser AIT below 120. Compound charging will just increase your AIT even more.
Also what is up with your AIT being so high especially when the BW turbos are so much win? On my unhappy over spun m62 heatgun I see AIT of 100 after the IC. On my old volvo with an inefficient ebay turdblow and IC behind the ac condenser AIT below 120. Compound charging will just increase your AIT even more.
#35
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The Blower wont restrict flow. It will make heat which will be what limits you. You see, this setup will be somewhat hard to control boost on. For simple sake lets just assume that the blower is working on a fixed 2:1 pressure ratio. That means if the turbo isnt spooled (0psig at blower inlet) you will be making 15psig in the intake manifold, now if the turbo is outputting 15psi at the blower inlet you'll have 45psig in the intake manifold, and a lot of heat. If the bpv on the blower has its vac hoses routed like stock it'll stay closed when there's more pressure in the manifold than the blower inlet. The blower moves a fixed volume of air and not at fixed pressure ratio so it is a bit more complicated than the above. Also, proper intercooling of the air charge between the turbo and the blower is going to be crucial.
I think this is really cool, but it makes me pause for a why. This turbo should be spooled by 4.5k on a 1.8 miata with a decent setup, shifting (especially @8500rpm) shouldnt drop you out of the power band. You mainly drag race this car so I don't see why you care about the lower 4krpm of the rev range when you shouldn't ever see that during a race assuming you don't mess up the launch. And you have a jesus EFR turbo, even that massive thing should have better throttle response than some crappy journal bearing jobby made in china.
I still want to see you do this.
I think this is really cool, but it makes me pause for a why. This turbo should be spooled by 4.5k on a 1.8 miata with a decent setup, shifting (especially @8500rpm) shouldnt drop you out of the power band. You mainly drag race this car so I don't see why you care about the lower 4krpm of the rev range when you shouldn't ever see that during a race assuming you don't mess up the launch. And you have a jesus EFR turbo, even that massive thing should have better throttle response than some crappy journal bearing jobby made in china.
I still want to see you do this.
#36
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spray the house down with e85 to battle the heat (run it EVERYWHERE lol: main injectors, aux injectors, spray nozzles, whatever) and go for glory ![Party Kitty](https://www.miataturbo.net/images/smilies/birthday[1].gif)
I now know from personal experience that you absolutely have to use the aux injectors that are in the manifold, otherwise you're gonna have a bad time
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I now know from personal experience that you absolutely have to use the aux injectors that are in the manifold, otherwise you're gonna have a bad time
#37
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The Blower wont restrict flow. It will make heat which will be what limits you. You see, this setup will be somewhat hard to control boost on. For simple sake lets just assume that the blower is working on a fixed 2:1 pressure ratio. That means if the turbo isnt spooled (0psig at blower inlet) you will be making 15psig in the intake manifold, now if the turbo is outputting 15psi at the blower inlet you'll have 45psig in the intake manifold, and a lot of heat. If the bpv on the blower has its vac hoses routed like stock it'll stay closed when there's more pressure in the manifold than the blower inlet. The blower moves a fixed volume of air and not at fixed pressure ratio so it is a bit more complicated than the above. Also, proper intercooling of the air charge between the turbo and the blower is going to be crucial.
I think this is really cool, but it makes me pause for a why. This turbo should be spooled by 4.5k on a 1.8 miata with a decent setup, shifting (especially @8500rpm) shouldnt drop you out of the power band. You mainly drag race this car so I don't see why you care about the lower 4krpm of the rev range when you shouldn't ever see that during a race assuming you don't mess up the launch. And you have a jesus EFR turbo, even that massive thing should have better throttle response than some crappy journal bearing jobby made in china.
I still want to see you do this.
I think this is really cool, but it makes me pause for a why. This turbo should be spooled by 4.5k on a 1.8 miata with a decent setup, shifting (especially @8500rpm) shouldnt drop you out of the power band. You mainly drag race this car so I don't see why you care about the lower 4krpm of the rev range when you shouldn't ever see that during a race assuming you don't mess up the launch. And you have a jesus EFR turbo, even that massive thing should have better throttle response than some crappy journal bearing jobby made in china.
I still want to see you do this.
I also agree about proper intercooling. This is something I'm going to be redoing. I have to take some measurements to get a better idea of what I can do. I'm going to put the biggest one I can with a pair of badass fans on it.