The Twin Screw Thread
03-11-2010, 03:42 PM
#2161
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blau928
You meantioned compound boosting. Google Hellion project. It is a stock cobra that they compound boosted. It has been a year at least since I read it but they started to have the heads lift off the block at a high numbers, something like 34lbs. When they compound boosted the cobra they were able to acheive 44lbs or so and 1100rwhp from a stock block and the heads wouldn't lift.
Not that I would suggest anything like that for a 928. I looked into adding a turbo to my SC as the eaton M90 ran out of steam at the higher rpm. The idea was to use the blower for bottom end power and size the turbo to take over on the top.
As you stated the TS is very capable of producing power through till redline so a turbo really wouldn't be needed but would be really cool.
The TS will provide all the power that the engine and drivetrain can handle and they sound really COOL!
Stephen
You meantioned compound boosting. Google Hellion project. It is a stock cobra that they compound boosted. It has been a year at least since I read it but they started to have the heads lift off the block at a high numbers, something like 34lbs. When they compound boosted the cobra they were able to acheive 44lbs or so and 1100rwhp from a stock block and the heads wouldn't lift.
Not that I would suggest anything like that for a 928. I looked into adding a turbo to my SC as the eaton M90 ran out of steam at the higher rpm. The idea was to use the blower for bottom end power and size the turbo to take over on the top.
As you stated the TS is very capable of producing power through till redline so a turbo really wouldn't be needed but would be really cool.
The TS will provide all the power that the engine and drivetrain can handle and they sound really COOL!Stephen
Thanks for sharing the link. I took my inspiration for twin charging from the Lancia Delta Integrale Rally car from a decade or so ago, and some other research material I have purchased on forced air induction systems..
On the other hand, I think the performance of the 928 32V motor will be similar to the 32V Ford setup in general terms, and 5-6 years ago made a comparison of a 32V Cobra with 700+ RWHP using an Autorotor Twin Screw Compressor... I think a Twin Screw 928 S4 motor is capable of this kind of output when done properly.
The increase in the airfow of a twin charged system is a result of the combined pressure ratio of the multiple compressors versus working with one compressor's internal pressure ratio.
Using the Eaton et. al. for lower end, and sizing the turbos for upper end is exactly what the benefits of twin charging offer. When done in certain applications, the blower drive belt actually also transmits power into the crank as well. (It has to do with sizing the turbos and the airflow etc..)
The TS compressors can flow across the RPM range, but there needs to be attention paid to the size of the compressor, and it's flow capacity and pulley ratio based on the engine it will be used with.
Yes, they sound really cool, one of the memorable moments in inspiration was being taken for a "spin" in a Mc Laren Mercedes SLR.. Some people don't like the sound, but I do.. (It is caused by the pulsations of the air in the intake tract and plenum from the screw compressor. Kind of like a popping sound that turns into a scream at redline.)
Cheers,
03-11-2010, 04:17 PM
#2162
Captain Obvious
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A TS witha a turbo will add power to the crank? What application is that
I will reply back on the bottleneck post when I get home.
I will reply back on the bottleneck post when I get home.
03-11-2010, 07:07 PM
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OMG...You guys are seriously full of hot air !! 
I would love to buy Daves system but there is a long waiting list, and I want to drive my shark with some blown HP now. By the time you guys get done puffing up your chest and blowing out hot air, I will be driving a sweet blown black 89 928s4 with Magnacharger under the hood. It won't be as cool or high tech, but it is somewhat like Richards setup. I have figured out how to use the stock intake all the way to and past the weird big stock trottle body. The Idle valve, maf, air filter and everything stays where it is. The intake manifold is made out of welded steel for now and not intercooled (only 5psi), cuz I am a cheap s.o.b, but I want to melt some tires and turn some heads. Plus I only have $600 invested at this point.
I will post some pics for you windbags soon. Now if I could just come up with, or someone would sell me crank pulley I would be golden ... hint hint Tim
I would love to buy Daves system but there is a long waiting list, and I want to drive my shark with some blown HP now. By the time you guys get done puffing up your chest and blowing out hot air, I will be driving a sweet blown black 89 928s4 with Magnacharger under the hood. It won't be as cool or high tech, but it is somewhat like Richards setup. I have figured out how to use the stock intake all the way to and past the weird big stock trottle body. The Idle valve, maf, air filter and everything stays where it is. The intake manifold is made out of welded steel for now and not intercooled (only 5psi), cuz I am a cheap s.o.b, but I want to melt some tires and turn some heads. Plus I only have $600 invested at this point.
I will post some pics for you windbags soon. Now if I could just come up with, or someone would sell me crank pulley I would be golden ... hint hint Tim
03-12-2010, 10:13 AM
#2164
Captain Obvious
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OMG...You guys are seriously full of hot air !!
I would love to buy Daves system but there is a long waiting list, and I want to drive my shark with some blown HP now. By the time you guys get done puffing up your chest and blowing out hot air, I will be driving a sweet blown black 89 928s4 with Magnacharger under the hood. It won't be as cool or high tech, but it is somewhat like Richards setup. I have figured out how to use the stock intake all the way to and past the weird big stock trottle body. The Idle valve, maf, air filter and everything stays where it is. The intake manifold is made out of welded steel for now and not intercooled (only 5psi), cuz I am a cheap s.o.b, but I want to melt some tires and turn some heads. Plus I only have $600 invested at this point.
I will post some pics for you windbags soon. Now if I could just come up with, or someone would sell me crank pulley I would be golden ... hint hint Tim
I would love to buy Daves system but there is a long waiting list, and I want to drive my shark with some blown HP now. By the time you guys get done puffing up your chest and blowing out hot air, I will be driving a sweet blown black 89 928s4 with Magnacharger under the hood. It won't be as cool or high tech, but it is somewhat like Richards setup. I have figured out how to use the stock intake all the way to and past the weird big stock trottle body. The Idle valve, maf, air filter and everything stays where it is. The intake manifold is made out of welded steel for now and not intercooled (only 5psi), cuz I am a cheap s.o.b, but I want to melt some tires and turn some heads. Plus I only have $600 invested at this point.
I will post some pics for you windbags soon. Now if I could just come up with, or someone would sell me crank pulley I would be golden ... hint hint Tim
03-12-2010, 05:03 PM
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Nice $1000 ... now we are talking.... how does she run? Are you using stock injector or did you go up to 25's with a reg. I have read through this whole thread and there is a tons of good information in here, but the last page few pages of fluid dynamics, and multiple compressor ratios, and other hot air were boring me to tears. Just my worthless opinion HaHa. If you have any pictures of your setup, or tips I would welcome the info with a
03-12-2010, 05:30 PM
#2166
Captain Obvious
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clink on the link (in grey) in mt signature. Did a build thread back then too, feel free to have a look at it but since it's not a TS but a CS, might not be apropriate to discuss it here. Send me a PM. The injectors are stock 24lb units.
03-23-2010, 09:58 PM
#2168
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I worked out a solution for my air filter to the Maf over the weekend.
Everyone has a problem running under the crossbar, especially running 4 inch diameter up to a reducer in front of the Maf.
So what I did was use a rubber sections and then cut two small interior aluminum bands about 2 inches in width to use as the connectors.
Instead of cobbling this up with clamps I roughed up the aluminum with coarse sand paper and then bonded the piece with a mutlipe use 60 minute set Epoxy.
This allows the rubber to deform slightly under the crossbar but maintains the cross section better than what I had before which was an irregular "crushed" piece of aluminum between the 4 inch elbow and the reducer.
I think this cleans up the install.
Regards,
Ken
Everyone has a problem running under the crossbar, especially running 4 inch diameter up to a reducer in front of the Maf.
So what I did was use a rubber sections and then cut two small interior aluminum bands about 2 inches in width to use as the connectors.
Instead of cobbling this up with clamps I roughed up the aluminum with coarse sand paper and then bonded the piece with a mutlipe use 60 minute set Epoxy.
This allows the rubber to deform slightly under the crossbar but maintains the cross section better than what I had before which was an irregular "crushed" piece of aluminum between the 4 inch elbow and the reducer.
I think this cleans up the install.
Regards,
Ken
Last edited by Vlocity; 03-23-2010 at 10:37 PM.
07-31-2010, 02:12 AM
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Let me start by saying......
A smart man learns from his mistakes, and a wise man learns from others mistakes. Then there's the Fool,,,,, Well he is cheap and impatient and develops his own twin screw kit for his 89 928s4. Don't be this guy!!! spend some cash, be patient, and get your name in on the waiting list, and buy Daves kit at 928GT.com. Or go with murfs kit, or whatever good kit floats your boat. That way you can drive your car, have a life, eat home cooked meals, ect ect, maybe even save a little hair, LOL.... Cuz this is/was a poop load of work and time... what was I thinking
Ok that said.... I am finally seeing light at the end of the tunnel... After many months of not driving my car, many late nights figuring things out, and a lot of Arbys, I'm quite close.
My goal was to keep the car as stock as possible while installing a twin screw. To am literally only replacing the stock intake with a twin screw and new manifold. It looks like it is accomplished. Obviously there is some fine tuning with the air/fuel, but the injectors, rails, air filter, weird split throttle body assembly, and much much more stay exactly where they are. The hard stuff is done.. cutting, measuring, bending, welding. I just can't imagine what the cost would be if I didn't have the ability and everything at my disposal.
Anyway here is a couple pics of things on the process and trials. I am leaving town for a couple weeks for a work confrence and will probably not drive the car before I leave, but I am determined to drive it before summer ends here in Michigan.
A smart man learns from his mistakes, and a wise man learns from others mistakes. Then there's the Fool,,,,, Well he is cheap and impatient and develops his own twin screw kit for his 89 928s4. Don't be this guy!!! spend some cash, be patient, and get your name in on the waiting list, and buy Daves kit at 928GT.com. Or go with murfs kit, or whatever good kit floats your boat. That way you can drive your car, have a life, eat home cooked meals, ect ect, maybe even save a little hair, LOL.... Cuz this is/was a poop load of work and time... what was I thinking
Ok that said.... I am finally seeing light at the end of the tunnel... After many months of not driving my car, many late nights figuring things out, and a lot of Arbys, I'm quite close.
My goal was to keep the car as stock as possible while installing a twin screw. To am literally only replacing the stock intake with a twin screw and new manifold. It looks like it is accomplished. Obviously there is some fine tuning with the air/fuel, but the injectors, rails, air filter, weird split throttle body assembly, and much much more stay exactly where they are. The hard stuff is done.. cutting, measuring, bending, welding. I just can't imagine what the cost would be if I didn't have the ability and everything at my disposal.
Anyway here is a couple pics of things on the process and trials. I am leaving town for a couple weeks for a work confrence and will probably not drive the car before I leave, but I am determined to drive it before summer ends here in Michigan.
Last edited by victor25; 04-23-2013 at 04:15 PM.
08-04-2010, 12:13 AM
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Sweet... thanks for the invite I realy dought I will have my 928 together by then though, and if I showed up in my other S4 you guys would probobly stone me....LOL. Cuz its and Audi. It wears the s4 badge well though, its an AWD 4000hp twin turbo v6 ..
I will give it a shot. It's not like I want to stay in town for my x-wifes wedding this weekend....EEEEKKK!!!
I realy dought I will have my 928 together by then though, and if I showed up in my other S4 you guys would probobly stone me....LOL. Cuz its and Audi. It wears the s4 badge well though, its an AWD 4000hp twin turbo v6 .. I will give it a shot. It's not like I want to stay in town for my x-wifes wedding this weekend....EEEEKKK!!!
08-04-2010, 12:50 AM
#2174
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what are you guys using for your belt-wrap rollers? i recall seeing a 928 blower setup something like this detailed engineering drawing. would just any idler work or something specific, a tensioner perhaps?
found a pic earlier in the thread.
found a pic earlier in the thread.
08-04-2010, 01:18 AM
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THAT is very cool. Well done. I always wanted to see one mounted like that. If you can smooth the airflow coming out of the top and into the runners it will be worth while.
