Author Topic: Boosted Applications... Turbo/Supercharger  (Read 58925 times)

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Offline HavocTurbo

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Boosted Applications... Turbo/Supercharger
« on: September 21, 2009, 10:41:35 AM »
Could be the wrong way to go about this... But here goes nothing.

I've used a lot of different turbos over the years. Ones off of cars, brand new ones, even a turbo off of a boat.

What do you use? Make and Model?

And on top of that what system do you prefer? Draw through? Pressurized Carbs? Fuel Injection?

Probably my favorite system to use is the fuel and ignition system off of a 84-85 Kawi 750 Turbo and a turbo from a comparable year Saab 9000t. Of course that's Fuel Injection.

For carburetion I prefer a single carb draw through maybe a Mikuni HSR24?

My preference as of late is an Air Research (Garret) T2 Turbo. Doesn't seem to be too big for the 900 and lower cc bikes. Plus the 4 bolt mounting flange is extremely easy to fab to different application.
« Last Edit: November 06, 2009, 03:22:59 PM by HavocTurbo »
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Offline voxonda

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Re: Turbo Applications... i.e. What Model Turbo & Draw System
« Reply #1 on: September 21, 2009, 11:19:29 AM »
In my former Turbo I used the Airtech T2 together with the Mikuni HSR42. I preferred the 'old skool' draw through despite some of the set backs. I loved the rough idling, people kept turning their heads at traffic lights.
Of course the fuel injected system are (much) better controllable, but I think it does not match our 'girl'.
Better sorry for failing then for the lack of trying.

Offline Bamboozler

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Re: Turbo Applications... i.e. What Model Turbo & Draw System
« Reply #2 on: September 21, 2009, 11:49:08 AM »
Like the topic. :)

Since later July I've been fabbing a blow through system on my 78F; the fab is for the most part done.  I'll throw up a post project review in the project forum when I have a running machine and troubles figured out.  The turbo I chose was a Ebay china direct T3 with the smallest A/R I could find .42 comp/.48 turbine... for $215 new in the box and out the door I was willing to pull the trigger.  Hoping that it will start to spool at a reasonable RPM.

The project has been a blast, I love the fabrication fun and games.  Definitely some challenges with these bikes and blow through that need to be over come (sealing up the carbs, electrical load management to name a few), hope this project takes flight with no show stoppers; its getting close to starting.

HavocTurbo, what boosted bike(s) do you have at the moment? 
'78 CB750F Turbo, 101 rwhp @ 8 PSI (Project thread)
2007 Yamaha FZ1
'78 CB750F basket case crying for a resto
'78 XL250S
'78 Suk GS750E
Digital Ignition project (Project thread)

Offline NitroHunter

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Re: Turbo Applications... i.e. What Model Turbo & Draw System
« Reply #3 on: September 21, 2009, 12:25:59 PM »
I have the Rajay FF, .25 turbine housing, and tiny 34mm carb. Don't remember the unit's trim. It was the Mr. Turbo kit sold in the 80's. I feel this combination is a real compromise. Too big a turbo for a small street bike, not enough carb for a racer. Too much CFM and WAY too much lag.
The B-25 ATP setup on my GS was much better suited to the street but could have used the smaller carb.

Good luck finding a readable Rajay compresssor map for either of these, I question whether the one I have is marked correctly...

I think digital injection is the only GOOD way to feed these things.

Can we adapt a flow/pressure compensated injection system that will reliably function with our stock charging system? Of course an integrated ignition retard should be mandatory...
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Offline HavocTurbo

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Re: Turbo Applications... i.e. What Model Turbo & Draw System
« Reply #4 on: September 21, 2009, 06:14:30 PM »
HavocTurbo, what boosted bike(s) do you have at the moment? 

I "had" a 85 Kawasaki GPZ750Turbo in stock electrical trim.

T2 - Had it sitting on the shelf.
Hardwired PC3USB into the stock system from a 00 YZF-R1.
Several maps to get it to the track and then go down it fast.
"Race Mode" Enabled on the stock ECU
Type-S BOV from TurboXS
50mm External Wastegate - Cannot remember the brand.
2mm collector tube increase for the modified turbo flange. I think stock was 1.5" tubing?
Custom aluminum intake tubes with custom pre-throttle body manifold.
GPZ1100 Throttle Bodies
Larger injectors from Saab 9000t (Bosch Style) 350cc? Can't remember.
Custom Map - Never been on a dyno.
21lbs of boost.
Rear Swingarm from a 00 Busa.
Front end off of a 08 ZX14 plus both front and rear wheels.

Got to hear it run for 5 days and take 12 passes down a strip before a nice drunk lady tried to kill me at a stop light in broad daylight. >:(

Next turbo'd application will be my CB750 with as much as my bank account can muster.  :D
'48 HD Panhead - Exxon Valdez
'78 CB550K - Fokker CB.3
'78 Honda CB750K - Mavrik
'80 Yamaha XS850G - Kanibalistik
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Offline Bamboozler

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Re: Turbo Applications... i.e. What Model Turbo & Draw System
« Reply #5 on: September 22, 2009, 07:59:03 AM »
Sounded like a sweet ride HavocTurbo, you had to have fun planning and executing that bike!  Unfortunate that it had to come to a end so soon... :(  It would be a treat to be able to play with fuel injection on the CBs.  The control and abilities to teak the maps as you noted is half the fun.  I'd love being able to have the CB play with electronic fuel management.  I wish the CB could withstand 21psi in stock form too!

Unfortunately it seems that the achilles that limits how much you can do is the charging system.  I'm already sweating breaking the bank and running into a charging deficit while managing the two additional pump loads (fuel and oil scavenge).  I'm having to cut the power consumption/speed of the pumps via a regulator to spare excessive power draw (a tight rope walk finding and setting the max power the pumps need and not giving them a bit more). I'm finding that any additional loads are becoming a pipe dream. I'm hoping that the wide band O2 will squeeze in, but that will be railing the output of the generator if not exceeding; and won't permit idling for too long.  This is after playing the LED bulb swap game; toggling the head light gives some room to breath. Think it may be worthy investigating a method of higher output generators for these bikes.

I'd love to see these CBs able to supply 30amps/14.xV... ;D You could have all the toys and then some!
'78 CB750F Turbo, 101 rwhp @ 8 PSI (Project thread)
2007 Yamaha FZ1
'78 CB750F basket case crying for a resto
'78 XL250S
'78 Suk GS750E
Digital Ignition project (Project thread)

Online MRieck

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Re: Turbo Applications... i.e. What Model Turbo & Draw System
« Reply #6 on: September 22, 2009, 08:20:57 AM »
 To bad you can't adapt a permanent magnet system off a busa or something. Maybe a fire engine alternator?? ;)
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Offline Bamboozler

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Re: Turbo Applications... i.e. What Model Turbo & Draw System
« Reply #7 on: September 22, 2009, 02:12:30 PM »
To bad you can't adapt a permanent magnet system off a busa or something. Maybe a fire engine alternator?? ;)

I agree! :) You would think some cross application would work with a little engineering. Without diluting this thread's original topic too much I think it would be helpful to pool some ideas toward this subject in another thread.  I've seen the topic touched on here and there in scattered charging related threads, but haven't found a dedicated thread that looks to find a higher output solution (maybe I didn't search enough).  I know Cyclex has a permanent magnet alternator, but it doesn't give an additional output that would help projects like turbocharging and fuel injecting forget the limits of a charging deficit. Think of the projects that could take off if there was an ample supply of current... I want that pump, I want that fuel computer, I want those coils... no restraints would be nice. 8)
« Last Edit: September 22, 2009, 02:20:27 PM by Bamboozler »
'78 CB750F Turbo, 101 rwhp @ 8 PSI (Project thread)
2007 Yamaha FZ1
'78 CB750F basket case crying for a resto
'78 XL250S
'78 Suk GS750E
Digital Ignition project (Project thread)

Offline HavocTurbo

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Re: Turbo Applications... i.e. What Model Turbo & Draw System
« Reply #8 on: September 22, 2009, 10:36:52 PM »
I'd love being able to have the CB play with electronic fuel management. 

It can be done. I'm thinking about working with parts off a GPZ1100 or the 750Turbo itself. Might take me my whole life to do it and get it reliable.... But I'm ok with that.

I wish the CB could withstand 21psi in stock form too!

Don't misunderstand. I went over everything. Big bore Kit, machined cases and head tops and bottoms (to make sure they were flat), o-ringed block, 2 piece copper gasket, the works. I wanted a very streetable bike that could be a monster at the lights on a strip. Took me years to do. Well one and a half. Lots of trial and error. Never got past the initial tests and tunings though. Still makes me sad.

To bad you can't adapt a permanent magnet system off a busa or something. Maybe a fire engine alternator?? ;)

Why not just machine a cover to expose the shaft end, press on a pulley and run an alternator? Not very stock looking but.... eh. We're talking high performance here right? I say go balls out.  :D ;) ;D
'48 HD Panhead - Exxon Valdez
'78 CB550K - Fokker CB.3
'78 Honda CB750K - Mavrik
'80 Yamaha XS850G - Kanibalistik
09 XL883L - No Name

Offline NitroHunter

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Re: Turbo Applications... i.e. What Model Turbo & Draw System
« Reply #9 on: September 23, 2009, 07:43:23 AM »
Hav, do you know exactally how much power it took to run the complete GPZ system?
Has anyone calculated what we need to run an injection system of any type?
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Offline Bamboozler

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Re: Turbo Applications... i.e. What Model Turbo & Draw System
« Reply #10 on: September 23, 2009, 11:36:51 AM »
Don't misunderstand. I went over everything. Big bore Kit, machined cases and head tops and bottoms (to make sure they were flat), o-ringed block, 2 piece copper gasket, the works. I wanted a very streetable bike that could be a monster at the lights on a strip. Took me years to do. Well one and a half. Lots of trial and error. Never got past the initial tests and tunings though. Still makes me sad.

Ahh, makes more sense now.  I had read that the GPZ750 Turbo came from the factory with stronger internals and thought you might have been stretching the limits. :)


With regards to graphing a pulley and alternator setup, I think something like that will have to be done.  I seen a picture of a member that had mounted a belt driven alternator externally in front of the motor, gets the job done. If its possible that the solution fits into the stock location and behind the cover I think it would be preferable.  But if not, I'd be OK with a external or modified case solution if I got my power.

I have been pondering this and have a few thoughts.  Four ways to get a higher output generator, 1). Alternating the stock system to achieve a higher output. 2). Graphing in a permanent magnet rotor and stator from a newer bike. 3). Graphing in a mini automotive belt style alternator that was mentioned.  4). Develop nuclear fusion and have all the power we want in the size of pack of smokes... ;D

I contacted Rick's Motorsports Electrics yesterday and asked if there was ever thoughts or work put into developing a higher output generator for the CBs currently or in the past.  There wasn't any engineers present to speak to, but the person that I talked to said they would look into it and call me back.  Kinda don't think they have anything or it would be making them money right now. It would be a long shot that they would be actively developing something right now. But who knows, maybe we can get lucky.

Regarding modifying the current system.  I'm wondering what the weak link in our system is right now in comparison to the 350-450 watt permanent magnet systems.  Is it a smaller/weaker magnetic field strength that the field coil generates, or is is the stator dropping the ball because it has too few turns of copper wire and trashing the turns ratio?  If the field coil magnetic generation is the problem, could you remove that hunk of metal from the cover, replace it with a similar dimension circular container that has many neodymium magnets oriented to deliver the same magnetic lines of flux as the stock field coil delivers into the rotor, and replace the regulator with a shunting type that the newer permanent magnet generators use? The magnetic field would be much stronger and should generate more current.  But how much more? What's the goal?  I think 300-400 watts total output would be considered a win.  Kinda think the stator would have to be improved as well to get anywhere close to 100 more watts of output... Would the lamination on the stock stator even be able to take on that much more current? thoughts?
'78 CB750F Turbo, 101 rwhp @ 8 PSI (Project thread)
2007 Yamaha FZ1
'78 CB750F basket case crying for a resto
'78 XL250S
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Offline HavocTurbo

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Re: Turbo Applications... i.e. What Model Turbo & Draw System
« Reply #11 on: September 23, 2009, 12:47:17 PM »
Not exactly no. I do know that it was a larger stator physically than the original 750 N/A.

Hav, do you know exactally how much power it took to run the complete GPZ system?
Has anyone calculated what we need to run an injection system of any type?


Stock GPZ internals are N/A 750 rods and crank (with a different stator end cut for larger output) stock Kz650 head and internals. Only thing specific to the turbo was pistons, camshafts, and trans gear ratios.

Ahh, makes more sense now.  I had read that the GPZ750 Turbo came from the factory with stronger internals and thought you might have been stretching the limits. :)
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'78 CB550K - Fokker CB.3
'78 Honda CB750K - Mavrik
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09 XL883L - No Name

Offline NitroHunter

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Re: Turbo Applications... i.e. What Model Turbo & Draw System
« Reply #12 on: September 23, 2009, 01:39:36 PM »
Just trying to narrow this down, has anyone EVER successfully run ANY electronic fuel injection on a CB750?
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Offline HavocTurbo

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Re: Turbo Applications... i.e. What Model Turbo & Draw System
« Reply #13 on: September 23, 2009, 03:42:56 PM »
Just trying to narrow this down, has anyone EVER successfully run ANY electronic fuel injection on a CB750?

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Offline j squared

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Re: Turbo Applications... i.e. What Model Turbo & Draw System
« Reply #14 on: September 24, 2009, 09:00:14 AM »
I am a noob to motorcycles as a whole but have a lot of forced induction experience on cars.  having said that, I cant believe yall are running such big turbos!! A T3 .48 exhaust housing on a sub-liter motor?  Wow, thats intense.  I was seriously expecting like a GT2535 to be the biggest frame possible for a motorcycle.

Offline Bamboozler

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Re: Turbo Applications... i.e. What Model Turbo & Draw System
« Reply #15 on: September 24, 2009, 10:09:59 AM »
My turbo experience comes from the auto world too, turbocharging the Mitsubishi 4G63.  If you do a direct ratio of what they throw on those guys with a 2.0L/1999cc motor the T3 isn't too far out of the ball park.  Check out www.turbo-bike.com and check out what the different builds there are using, a lot of straight T3s, T3/T4s with 750-1200cc bikes. Granted the CBs are 2 valve and air cooled vs the 4 valve liquid like a lot of those bike are; but a T3 on a CB doesn't seem too ridiculous in comparison.

My driver for taking a spin with the T3 .48 was pushed largely from the price of the turbo. I figure if I can get the guy to spool at a reasonable RPM I have good head room to work with with the boost is turned up with a bullet proof motor.  I agree that a smaller T2 or GT12, GT15 would better match our displacement for street use.  Just wanted to see if a $600+ cheaper turbo can get the job done. ;D
'78 CB750F Turbo, 101 rwhp @ 8 PSI (Project thread)
2007 Yamaha FZ1
'78 CB750F basket case crying for a resto
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Offline j squared

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Re: Turbo Applications... i.e. What Model Turbo & Draw System
« Reply #16 on: September 24, 2009, 10:55:39 AM »
yeah that makes sense when you look at 4G's, SR's, B-series, etc motors using large frame turbos like a T67 or a 60-1.  They work, so a small T3 on a bike would be about the same. 

So I guess youre looking for overall power with that turbo?  What kind of spool are you looking at, say on a CB750 with the turbo youre using?  Also can you use compressor maps the same way you can for a car motor when choosing a turbo?  i apologize for the newb questions but this is pretty awesome to me.

Offline Bamboozler

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Re: Turbo Applications... i.e. What Model Turbo & Draw System
« Reply #17 on: September 24, 2009, 12:25:26 PM »
Sounds like you're a turbo 4 guy, what camp to you call from?, DSMs, honda, subies..?

To tell you the truth I didn't consult any compressor maps being that the price was more of driver than what RPM I was going to see full boost.  I'm guessing that I will see full boost in the 6-7k range and hoping that its sooner than later.  In any case I think it will be a blast once its dialed in, and when I have enough scratch to throw at a motor the fun will really start. :)  As said before I found a turbo that was easy on the pocket book and fit the general size I was looking for; not the most ideal way to go about but I don't think I'm going to be too disappointed with what I pulled the trigger on.

Just had an epiphany on the way to work the A.M. regarding my charging dilema, one of those "why didn't I think of that soon stupid".  I'm sitting at around 160 watts of draw with both fuel and oil scavange pumps on, HID head light on and other parasitic loads... everything on without the motor (coils and alternator field coil) on.  I realized that I have both pumps (that must be running when the bike is running) wired to the battery individually; or in parallel. Seeing that they need to be on why am I not setting the regulator power limit to the higher loading pump and wiring the pumps together in series... I get two loads for the price of one..  Seeing that they will be running at half speed anyway the lighter loading motor will be fine getting a bit more current than it needs to do its job.  This will save me another 3 or so amps! ;D  Leaving for ATVing in the north woods in a bit, won't be able to try this out till next week, but that may give some needed breathing room.

i apologize for the newb questions but this is pretty awesome to me.

Nothing newb about it, couldn't agree with ya more, loving the project so far, its been a blast. Pic of the ride so far...

'78 CB750F Turbo, 101 rwhp @ 8 PSI (Project thread)
2007 Yamaha FZ1
'78 CB750F basket case crying for a resto
'78 XL250S
'78 Suk GS750E
Digital Ignition project (Project thread)

Offline j squared

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Re: Turbo Applications... i.e. What Model Turbo & Draw System
« Reply #18 on: September 24, 2009, 12:32:27 PM »
Whoa thats pretty freakin sweet!  Tial BOV? Ill bet that turns some heads ahahaha, nice looking fab work too on the plenum and manifold.

So, you have to run scavenging pumps for the turbo, and I can understand the oil scavenging, by why fuel?  I dont know crap about carbs so bear with me :)  But yeah, I do a lot of work on Nissans, mostly SR20 and RB20/25.  Ive been around some Mitsu shops in the pat, and know a little about Toyota I6's. Here is my current project, just came together a few months back (hence the recent CB550 purchase :) ):



Offline Bamboozler

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Re: Turbo Applications... i.e. What Model Turbo & Draw System
« Reply #19 on: September 24, 2009, 01:09:53 PM »
Thanks for the comments.  Nice looking ride you get to play with as well!  Love how much room you have in the bay. Seems like you could replace in timing belt in no time. ;D  Car looks quite clean!

Regarding the pump, I'm running two pumps, one for fuel feed and only one for scavenging purposes, oil in this case.  The fuel pump has to feed the carb bowls, but it feeds a typical turbo app 1:1 rising rate bypass regulator (psi fuel per lb of boost), which in turn feeds the carb rack; very similar to what you are running with your car.  I welded a fuel return fitting to the top of the tank for the bypass. 

The oil scavenge pump is not entirely needed if I would have mounted the turbo higher than the sump.  I wanted to have the turbo in the front and there was no real other choice other than to pump the turbo drain oil back into the motor or tap into the pump system inside the motor (opted not to mess with that one).  Another option is to mount the turbo in the vicinity of the airbox/battery which elevates the drain enough to gravity feed it back into the motor and spares you having to add a oil scavenge pump.

The only thing needed to do with these carbs is seal up the choke and throttle shafts with o-rings to prevent a boost leak as well as making sure your fuel feed tubes have good sealing o-rings and gaskets on the float bowls for the added fuel pressure.  Currently waiting on float bowl gaskets to arrive and I think I should have a sealed rack-o-carbs and can then proceed to attempt a start up.
'78 CB750F Turbo, 101 rwhp @ 8 PSI (Project thread)
2007 Yamaha FZ1
'78 CB750F basket case crying for a resto
'78 XL250S
'78 Suk GS750E
Digital Ignition project (Project thread)

Offline NitroHunter

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Re: Turbo Applications... i.e. What Model Turbo & Draw System
« Reply #20 on: September 24, 2009, 01:19:31 PM »
Bam, that's a great looking system you've got there!
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Offline j squared

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Re: Turbo Applications... i.e. What Model Turbo & Draw System
« Reply #21 on: September 24, 2009, 01:27:26 PM »
Thanks for the comments.  Nice looking ride you get to play with as well!  Love how much room you have in the bay. Seems like you could replace in timing belt in no time. ;D  Car looks quite clean!

Regarding the pump, I'm running two pumps, one for fuel feed and only one for scavenging purposes, oil in this case.  The fuel pump has to feed the carb bowls, but it feeds a typical turbo app 1:1 rising rate bypass regulator (psi fuel per lb of boost), which in turn feeds the carb rack; very similar to what you are running with your car.  I welded a fuel return fitting to the top of the tank for the bypass. 

The oil scavenge pump is not entirely needed if I would have mounted the turbo higher than the sump.  I wanted to have the turbo in the front and there was no real other choice other than to pump the turbo drain oil back into the motor or tap into the pump system inside the motor (opted not to mess with that one).  Another option is to mount the turbo in the vicinity of the airbox/battery which elevates the drain enough to gravity feed it back into the motor and spares you having to add a oil scavenge pump.

The only thing needed to do with these carbs is seal up the choke and throttle shafts with o-rings to prevent a boost leak as well as making sure your fuel feed tubes have good sealing o-rings and gaskets on the float bowls for the added fuel pressure.  Currently waiting on float bowl gaskets to arrive and I think I should have a sealed rack-o-carbs and can then proceed to attempt a start up.

nice, i didnt put two and two together but yeah a fuel pump would be a must Im sure.  Thats cool youre using a rising rate FPR, what are you using for the vacuum source?  This is really interesting, Ive never thought about what would be needed to turbo a carb'd bike, things like the boost leaks in the carbs and the extra fuel pressure probably make it so everything has to be 100% bombproof for it to run well.

Offline mgbgt89

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Re: Turbo Applications... i.e. What Model Turbo & Draw System
« Reply #22 on: September 24, 2009, 01:30:55 PM »
Whoa thats pretty freakin sweet!  Tial BOV? Ill bet that turns some heads ahahaha, nice looking fab work too on the plenum and manifold.

So, you have to run scavenging pumps for the turbo, and I can understand the oil scavenging, by why fuel?  I dont know crap about carbs so bear with me :)  But yeah, I do a lot of work on Nissans, mostly SR20 and RB20/25.  Ive been around some Mitsu shops in the pat, and know a little about Toyota I6's. Here is my current project, just came together a few months back (hence the recent CB550 purchase :) ):




That thing is kinda neat! Nice break from all the LSx powered FC's around. Why did you go with an SR?

Offline j squared

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Re: Turbo Applications... i.e. What Model Turbo & Draw System
« Reply #23 on: September 24, 2009, 01:49:25 PM »
Pretty much what you just mentioned, so many V8 RX7's out there and Ive only seen one other SR swap done. The wiring was a headache for sure, but its running with all the stock gauges, stock speedo/tach, fuel pump cutout like OEM, most of the warning lights operational, etc.  Really glad I took the time to do it "right."


Offline Bamboozler

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Re: Turbo Applications... i.e. What Model Turbo & Draw System
« Reply #24 on: September 24, 2009, 01:56:34 PM »
Thanks Nitro, appreciate the props!

Regarding the blow off valve. Just a Chinese Greddy Type S knock off that I picked up on Ebay for under $40 shipped.  Not that bad of a deal, machining doesn't seem too bad.

Vac source is tapped from the intake; see pic; props to my friend Mark who did all the tig work on the bike.  I'm choosing not to implement pitot tubes in the intercooler pipe with this setup. My buddy's turbo RX1 snowmobile (1000cc carbed yami R1 cycle motor) doesn't use them and all he had to do is fatten the mids a clip position, same main and idle jets.  I have a wide band O2 so tuning should be much less painful.  I'll see if there are any throttle response problems, but I don't see why there would be from the evidence I've seen. 

****  Edited to add that after reading/researching further I would be fighting myself for not adding boost comp to the system.  Way too much positive evidence that a pitot system helps verse the few sled kits that make it work without.  I haven't gotten to the point of spooling the turbo yet, but I ordered parts and will be adding the boost comp. :) ****


To note, I attached vac lines to the atmospheric pressure ports and plumbed them into the intake.  This will pressurized the float bowls with the same boost pressure that is flowing through the carbs; add a 3psi base fuel pressure and you always have a net of +3 psi in the bowls to ensure fuel flows out of the main/needle jets and into the boosted air charge.

Off to the forested ATV land, good weekend yall.

« Last Edit: October 20, 2009, 11:35:44 AM by Bamboozler »
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