ideas on triples, boost at low rpm

kawi600

kawi600

got Coal for Christmas
Ive seen some real trick looking triple setups recently and its got me thinking...
Could a triple setup be made to provide a small amount of boost from idle and up? Doesnt need to provide an insane amount of top end air.. maybe enough for 500-600hp.
Ive been eyeballing Carl's supercharger setup but Im still looking at all the options before I spend the coin.
Downside of turbos is the lag - the lack of boost in the low revs. Which leaves me either smoking people out or turning the AFC up to clean the haze. Not a whole lot of power off the line with it tuned like that. Unless you build boost on the brakes. Which attracts a lot of the wrong kind of attention on public roads.

So what do you all think? Could a triple set be sized to cover more of the low RPM and still make a fair amount of power up top?
 
I would think 3 He351's would support 600hp and build boost like crazy, although I have no personal experience. I plan to build a set next year possibly.
 
curious what folks see at idle with a set of towing twins. Even a couple PSI may be enough to clean up the low RPM.
 
Ever try running a turbine diverter valve on say...... a super b? That might build boost really fast? Or that might be a bad idea lol.
 
That seems like a lot of fab work for 500 horsepower. I'd get a quick spooling single and be done with it. If its not fast enough, see above...
 
Thinking on this more, the problem you would have is running to much boost while cruising down the highway to have good mpgs. You could could get an electronic rod actuator to control a diverter vavle and have it closed from say 800-1500 rpms then it opens you would spool quick but be able to keep low drive pressure and boost while cruising from 1600-2000 rpms. If you run the diverter valve conventionally off of boost pressure on a small enough charger that would create boost off idle it would probably stay closed while light load cruising or would constantly be trying to open and close probably causing surge. Or I could just be full or you know what. Just thoughts.
 
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Ghostman said:
Thinking on this more, the problem you would have is running to much boost while cruising down the highway to have good mpgs. You could could get an electronic rod actuator to control a diverter vavle and have it closed from say 800-1500 rpms then it opens you would spool quick but be able to keep low drive pressure and boost while cruising from 1600-2000 rpms. If you run the diverter valve conventionally off of boost pressure on a small enough charger that would create boost off idle it would probably stay closed while light load cruising or would constantly be trying to open and close probably causing surge. Or I could just be full or you know what. Just thoughts.
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you know.... there's this brand new thing out there called variable geometry.
 
adeso said:
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hmmmm. Now if you wanted to be really cool post the last turbo you could make up a exhaust turbine to power an alternator for cruising, or set it up to take this one off line. Or I have even thought about routing this one into the exhaust pre first turbine stage so it spins the turbos up faster than take if off line once the boost is up
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do you understand the words 'efficiency' and 'energy transfer'?
 
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If you need boost at idle to keep your smoke level down, have you considered the possibility that you need afc tuning instead?
 
yeah Ive also been watching the fleece controllers. that might be the way to go honestly.. but Im not sure what happens when you throw one into a twins setup. Youd need a means to create and store your own map of sensor data versus actuator position, and a lot of trial and error to make a map that performed well.
I might give them a call and get some more options for this build.

RonA, absolutely.. but the problem is when I dial out the smoke I get such crappy take off power its like driving a cement truck. engine makes a ton of noise and I go nowhere fast. People tailgating me and then cutting me off is getting old. Same deal if I open up the afc, except they get a dose of black lung for their troubles.
supercharger over turbo is the solution to this, but I need to hear from a neutral party thats had good results before I spend the coin on it.
my wallet took a beating on the last experiment I tried.
 
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This might be more along the lines of what you're looking for.

I don't think many people actually see boost at idle with twins.

Maybe a set of twins like the BD R700 or ATS 3000/5000 would get you close, but I doubt you would see 1psi.
 
Kaiserbailey said:
This might be more along the lines of what you're looking for.

I don't think many people actually see boost at idle with twins.

Maybe a set of twins like the BD R700 or ATS 3000/5000 would get you close, but I doubt you would see 1psi.
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I'm pretty sure nobody here sees 'measurable' boost at idle with a compound turbo setup.

RonA wins with the logical response-
 
kawi600 said:
Ive seen some real trick looking triple setups recently and its got me thinking...
Could a triple setup be made to provide a small amount of boost from idle and up? Doesnt need to provide an insane amount of top end air.. maybe enough for 500-600hp.
Ive been eyeballing Carl's supercharger setup but Im still looking at all the options before I spend the coin.
Downside of turbos is the lag - the lack of boost in the low revs. Which leaves me either smoking people out or turning the AFC up to clean the haze. Not a whole lot of power off the line with it tuned like that. Unless you build boost on the brakes. Which attracts a lot of the wrong kind of attention on public roads.

So what do you all think? Could a triple set be sized to cover more of the low RPM and still make a fair amount of power up top?
Click to expand...

A supercharger is pretty much the only way to do what you're looking for, if you need off idle response. The problem is that turbos need energy to drive, so enough fuel to create boost at idle is going to create smoke also.

I know Banks was able to make 808lb-ft at 1,200rpm a while back with their supercharged/turbocharged Dmax, and Carl told me that a big whipple with small pulleys (like in a drag setup) could make 10-15psi at a fast idle. No way any turbo is going to touch that.
 
It sure sounds like a super / turbo setup is the way to go. Only worry I have is inlet restriction on the turbo when you put the SC in front.. even with a bypass theres a vacuum.
I know routing the turbo into the SC was tried before, but I wonder if a bypass would work under pressure instead of vacuum in this case.
 
kawi600 said:
... but the problem is when I dial out the smoke I get such crappy take off power its like driving a cement truck. engine makes a ton of noise and I go nowhere fast. People tailgating me and then cutting me off is getting old. Same deal if I open up the afc, except they get a dose of black lung for their troubles...
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Sounds like your converter is too tight.
 
Seems like a supercharger would be bad for mileage. I'm interested to hear opinions on a small set of triples. Kawi, do you still have that Hamiltion head, or did you take it back to stock?
 
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