BlueZ31 Posted July 7, 2008 Share Posted July 7, 2008 I need help measuring something i have no idea how to, and its for an ongoing experiment of mine.. Ive got a garrett t3/t4 turbo 63 trim, 50 A/R internally regulated at 8psi and i need to know the shafts consistent speed at 7-8psi, ive heard anywhere from 15,000rpms all the way up to 200,000rpms, which is too wide of a margin, i just need to narrow it down to within 5,000rpms of what it might be running at.... Thanks and hope you guys can help me, and when i complete my experiment im fabricating ill definently post pics, i just need to figure this one bit of info out or the whole idea collapses! Quote Link to comment Share on other sites More sharing options...
mtcookson Posted July 9, 2008 Share Posted July 9, 2008 I can tell you a T04E 60 trim runs from around 50,000 RPM up to around 75,000 from ~11 lb/min to ~34 lb/min respectively at 8 psi (~1.5 PR). If you can find an exact compressor map of your turbo it should tell you what RPM the wheel is spinning at for a particular pressure and flow. T04E 60 trim: http://64.225.76.178/catalog/compmaps/fig16.html Quote Link to comment Share on other sites More sharing options...
hughdogz Posted July 10, 2008 Share Posted July 10, 2008 You can buy an actual speed sensor from Garrett! http://www.turbobygarrett.com/turbobygarrett/products/Accessories_continue_speed_sensor.html Easy to Use The Garrett® Turbocharger Speed Sensor works with any turbocharger to accurately determine compressor wheel speed. The instructions include detailed drawings of the exact machining specifications for all Garrett® GT catalog turbochargers as well as general guidelines for other compressor housing types. The Garrett® Turbocharger Speed Sensor Kit includes all necessary wiring for easy installation and simple data logging. Two Options Available Garrett® Turbocharger Speed Sensor Pro Kit - PN 781328-0002 The Garrett® Turbocharger Speed Sensor Pro Kit includes speed sensor, wiring harness, and installation instructions. Garrett® Turbocharger Speed Sensor Street Kit - PN 781328-0001 The Garrett® Turbocharger Speed Sensor Street Kit includes speed sensor, wiring harness, installation instructions and Garrett®-branded turbo speed gauge. Cheers (and happy boosting), -hughdogz Quote Link to comment Share on other sites More sharing options...
BlueZ31 Posted July 10, 2008 Author Share Posted July 10, 2008 Okay, ill spill my guts on my experiment, but NO laughing! My turbo is from my buddies volvo 5cyl, the timing belt slipped and sent valve/piston pieces into the exhaust side completely destroying it, so we threw it in the shed for later experimentation, and starting firing out ideas for uses for the compressor side since a rebuild would cost as much as a reman oe unit...and i came up with this idea..DONT LAUGH...lol..or at least dont post your laughing. Ive dealt in electronics for some time, and cars also, and seen some pretty cheap attempts at electronic boost like ebay bilge pumps or expensive and unnescessary ones like thomas knights electric roots-blower, but my idea is to seperate EVERYTHING from the compressor side back, to make it as light as possible while keeping the blades stable with no in/out side/side play, and hooking up a aluminum gear drive system to it. The motor were using is from a cordless circular saw ( 18v, 4,500 max load speed with sh*t loads of torque) and we would seperate the motor/wiring from the case and use a pressure switch under the vehicle throttle to activate it at a predetermined vehicle rpm *3,000* and since it uses battery packs it be easy to recharge and compact. with a 4500 w/load speed and minimum turbo shaft speed of 50,000 the smallest gear ratio i can come up with is 11:1 and most realistic gearing is 110t:10t or a larger tooth gear of 66t:6t*the motor itself has a large tooth 6t gear attached*. or possibly a friction-wheel drive,and id use graphite for lubrication as it would only see a marginal amount of day to day use, im sure the motor is up to the job, since the tool has a load speed of 4,500 and can cut through tile im assuming the motor has enough torque and a higher rpm than the tool itself (because of internal gearing) the only problem im having now is finding gears big and strong enough without a large amount of weight, and considering the compressor blade weighs around 1.5lbs compared to the weight of a larger diameter*8in* thick steel saw blade 50,000 rpms should be achievable, to tell the truth im really just interested in if it can make over 2psi, maximum of 4psi, but i dont know how fast id have to get the shaft spinning to achieve those numbers again, this is only an experiment due to pure boredom and ive always loved using electric motors in my ideas...any help or critisism is more than welcome, and if anyone can help me find gears that arent ridicoulously huge/small heavy or weak *all i can find are rc car gears and it doubt they would hold up to the task* id appreciate it! Quote Link to comment Share on other sites More sharing options...
cygnusx1 Posted July 10, 2008 Share Posted July 10, 2008 It takes a lot of horsepower to compress air to 8psi at the flow rates of a 2.8 liter engine at 6000rpms. Your limit is the HP of the electric motor. My engineering sense tells me that you won't net more HP gain at the wheels than the motor can produce. Energy is never free. My engineering sense is also often wrong, which is why I still need to use text books full of equations. Sounds like a fun project though. I once got my Z better engine response by duct taping a leaf blower to the intake. Quote Link to comment Share on other sites More sharing options...
JSM Posted July 10, 2008 Share Posted July 10, 2008 I once got my Z better engine response by duct taping a leaf blower to the intake. Good, now that someone has admitted this I never have to! LOL Quote Link to comment Share on other sites More sharing options...
BlueZ31 Posted July 10, 2008 Author Share Posted July 10, 2008 Air resistance was a concern of mine, and ive no doubt i couldnt make the 8psi max of the turbo, 4psi would be extremely lucky but id be very pleased (and shocked) with 2psi, i figure its worth a shot and if it fails ill just move on, I considered fabbing a bracked out of my old a/c pump and using a belt drive system (replacing the a/c pump itself with the turbo) im sure this could be done but that adds all sorts of stresses to the turbo and crank not to mention id have to still find the right gears, but i know for a fact the engine makes more than enough power to make it work, its just for how long! i also considered keeping the center shaft with the belt drive idea and filling the oiling system with GM supercharger oil/lucas oil stabilizer and capping it off and changing it every 3k miles or so. Come to think of it ill probably ditch the electric idea due to complications and just try n fab a bracket for it....we'll be testing it on my friends 3.0l windstar van prior to Z application, just to make sure of everything . I thought about using the camshaft gear drive system from a SBC considering the cover has provisions for a pulley to be mounted and their usually pretty strong gears, just have to get the right ratio id assume. Quote Link to comment Share on other sites More sharing options...
BlueZ31 Posted July 30, 2008 Author Share Posted July 30, 2008 Okay, now ive found a promising venture, its a shop-vac (no laughing!)thats been sitting in a storage shed at my work, and when i lifted the top off the canister, the motor and its housing looked unusually similar to the '50's paxtons used on studebakers and the '55 t-bird as an option, you know, the Godawfully huge thing that looked like it'd suck up a small bird or cat if it got in the way. Welllll...out of curiosity i went online and was suprised that the little 6.5hp *peak* 11 amp motor was able to make a supposed 65 inches of sealed pressure ( which - minus atmospheric 14.7- would be like, what, 3.5psi?) and 185cfm of air........i doubt thats enough to feed a 3.0L but still, if i could build a DC~AC inverter and run it off a good battery this might be able to do something, maybe? the inlet blades are shockingly similar to the compressor vanes on a centrifugal supercharger or a small turbo, anyways im taking it when i get a chance and will start F***ing around with it in my spare time out of boredom and what not, maybe find some unsuspecting 4-banger to experiment on, like my buddies 1.6l toyota *beast* as he calls it the only problem would be feeding the motor when the compressors not operating, im sure the setup would create a restriction so maybe some sort of bypass that closes when the motor kicks on? i dont know, its almost 3:30 in teh morning and im wired on Redbull with a mind that wont rest.... Quote Link to comment Share on other sites More sharing options...
HowlerMonkey Posted August 1, 2008 Share Posted August 1, 2008 I'm sure somebody can come close to how much actual shaft horsepower is sent to the turbo by exhaust gases at boost by crunching numbers but I'm not up to that task. Quote Link to comment Share on other sites More sharing options...
Xander Posted August 2, 2008 Share Posted August 2, 2008 check this out. Electric supercharger!!!. Not the ebay ripoff type. http://www.turbomagazine.com/tech/0406tur_knight_turbo_electric_supercharger/index.html Quote Link to comment Share on other sites More sharing options...
BlueZ31 Posted August 5, 2008 Author Share Posted August 5, 2008 Ive seen that before alot, but it looks a bit clumsy and i think the 6 car batteries it takes plus the weight of the system itself negates any power gains, roots blowers take alot more power to turn and i think he woulda been better of using a large turbo. Anyways, im in a split decision, should i use the 6.5 shop motor(a/c) that has a load speed of about 10,000rpms (its a compressor motor well suited to moving high volumes of air) OR a d.c. outboard trolling motor? its built to push against a much more dense material (water) and has several gearings and a battery monitor and speed selector built in it i could use, but ive heard its only good for about 2hp with a 2hr run time on a fully charged battery. Which should i give a shot? and would a larger diesel turbo be best to use for a low rpm motor to achieve some boost or a smaller lighter turbo and spin it faster? just throwing more ideas out there... Quote Link to comment Share on other sites More sharing options...
BlueZ31 Posted August 6, 2008 Author Share Posted August 6, 2008 wow, cygnusx1 just gave me an idea.. Every electric "turbo" or "supercharger" ive seen on youtube or ebay has attempted to directly drive the compressor Via electric motors or just sold bilge pumps and large ducted fans, but what if i were to use the turbo the way it was meant, such as driving the exhaust side? Ive researched it, and found a electric blower that uses less power than the vacuum motor (and is more compact) and is able to flow 410cfm at 230mph through a 2 3/4 inch tube, what if i were to build a attachment system that connected the blower to the exhaust side much like the exhaust manifolds and used air to drive it rather than directly with motor(s)? could the 410cfm and 230mph volume put enough force on it to spool it to some or any amount of psi? I know that exhaust gas is much denser and much more hot than normal air giving it a high velocity, i just thought maybe this might work, what do you guys think? Quote Link to comment Share on other sites More sharing options...
BlueZ31 Posted August 8, 2008 Author Share Posted August 8, 2008 And if MPH doesnt make the difference there are industrial blowers rated the same electrical power use that flow 1,400cfm and upwards.... Quote Link to comment Share on other sites More sharing options...
Z2000 Posted August 9, 2008 Share Posted August 9, 2008 There is no average shaft speed for 7-8psi. The shaft speed has everything to do with the turbo size and how much the engine takes on its own before you can even make posative pressure. The bigger the engine that needs to be fed = more shaft rpm's needed to make boost. To make a long story short, the engine eat lots of the turbos work before it can even produce + pressure. Hope this made sense... I just woke up... Its all just a ratio relative to engine size/rpm vs turbo size and disired boost. Quote Link to comment Share on other sites More sharing options...
BlueZ31 Posted August 9, 2008 Author Share Posted August 9, 2008 It does make sense, im going to hook this idea up to my 3.0l zx if it works and possibly a 3.8l camaro, and since im shooting for no more than 300hp i assumed that a 16g or similar turbo would work but would need to be spooled very quickly to fill the cylinders compared to maybe a diesel turbo from a 7.3l/6.0l...what do you guys think would require less effort to produce around 4-6psi of boost? Quote Link to comment Share on other sites More sharing options...
BlueZ31 Posted August 14, 2008 Author Share Posted August 14, 2008 Hmmm. started messing around again with the ac condenser, figured out i could run a 1 1/2 alternator pulley on the ac mount, and ( this is a rough guess) the diameter of the crank pulley for the ac condenser is about 6" which would mean if i used a 6-1 ratio of gears on the turbo compressor (maybe a 10 tooth and 60 tooth set from a transmission? or perhaps something from a old belt drive motorcycle?) meaning at 3,000 rpms (my target for boost to kick in) it would have a speed of about 72,000 and climb from there, so a relatively large compressor side might work in this manner... or even perhaps just make a bracket out of the ac condenser mount to fit a eaton m90 pilfered from my old buick ( which has been eating dust on a shelf in my room) which would eliminate the hassle of finding gears and a turbo and all that mess...plus im guessing the positive displacement blower would have to work less to produce boost compared to a 100,000rpm turbo compressor being gear driven and then crank driven... Quote Link to comment Share on other sites More sharing options...
HowlerMonkey Posted August 18, 2008 Share Posted August 18, 2008 A piezo pickup from radio shack should be able to give you a good scope trace from which you can determine shaft speed. Quote Link to comment Share on other sites More sharing options...
BlueZ31 Posted August 19, 2008 Author Share Posted August 19, 2008 yeah, too bad ive gotten rid of my old oscilloscope though..good thought thought, thanks! Quote Link to comment Share on other sites More sharing options...
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