TURBO

[youngy]

no but my cousin does..................we have GE Frame 9 machines....bit bigger than the Rolls stuff....................161000 hp

[steve speed]

off topic a bit ,,,did you know that the warehouse at donnington park the one near dunlop bridge it sell bike bits and tat when the racings on ,,used to belong to Rolls Royce,, it was for storing the stainless tube in vertical racks ,it was a fantastic place ,then they started to have problems with the tube leaking ,, it was discovered that the birds flying around inside the works were shitting ( sorry) down the tube ,,,it caused all sorts of problems which i had to sort , we made framework over the tube and put poly sheet over that , if you look up you can still see some of it to this day , i fitted it in 1980 !!!

[youngy]

lol I'll have a look next time I'm there!

[peasngravy]

has it got a 50mm front wheel ?? if it has its too big ,a 2lt BMW petrol has a 40mm wheel but the waste gate opens at about 12lb from memory,, try to get as late as poss front wheel from allied signal ,there is a world of difference in front wheels , and as you know the rears are made of inckanol (not sure if that's how you spell it ) i have done some experiments with these in jet planes and you have to use ceramic bearings they spool up a lot faster and are very tough,as you know its a floating bush that they use in most turbos but it needs loads of oil ,in the early days they tried normal ball bearings which are ok until you stop the engine then the soak back did the bearings in ,, your biggest problems are heat and bearings , but good luck

ok im thinking of using a daihatsu charade GTTI turbo which is an RHB51 without doing the math im hoping this will be ok as i only want to run 6psi its more of a "lets do that" than how fast can i do the quarter mile ...

[Killerwhale]

has it got a 50mm front wheel ?? if it has its too big ,a 2lt BMW petrol has a 40mm wheel but the waste gate opens at about 12lb from memory,, try to get as late as poss front wheel from allied signal ,there is a world of difference in front wheels , and as you know the rears are made of inckanol (not sure if that's how you spell it ) i have done some experiments with these in jet planes and you have to use ceramic bearings they spool up a lot faster and are very tough,as you know its a floating bush that they use in most turbos but it needs loads of oil ,in the early days they tried normal ball bearings which are ok until you stop the engine then the soak back did the bearings in ,, your biggest problems are heat and bearings , but good luck

ok im thinking of using a daihatsu charade GTTI turbo which is an RHB51 without doing the math im hoping this will be ok as i only want to run 6psi its more of a "lets do that" than how fast can i do the quarter mile ...

And when your done i can buy the complete kit from ya!!

[steve speed]

can you give more details on (GTTI turbo which is an RHB51 ) whats it off ? how old is it ? petrol or diesel ? to be honest 6lb is not so much but probably ok , i dont know ,,but to give you some idea we ran a 45mm wheel at 110,000 rpm and we got 19lb of thrust out the back ,but at 120,000 rpm you get a lot more thrust, we got 30lb of thrust ,, balance is CRITICAL at those revs ,and Ive just remembered at self sustain , (thats with the starter removed and its now running on its own) its now at 30,000 rpm it is developing about 6 to 8lb of thrust, you say you have done this before have you seen the variable nozzle guide vane if you can get a turbo with this on and somehow link it to your bike this will give more thrust at the bottom end as it alters the diffusion angle on to the back wheel ,, i seem to remember the Honda cx 650 had a turbo and it gave about 5lb of thrust ,,it was useless

[philk]

I was looking at the build pics on the German website.
If im right looking at the pictures,the gasses flow from turbo to plenum to carbs. shouldnt it be turbo to intercooler to plenum to carbs. If you dont have the intercooler you will get major det and melt the pistons,ie too much heat, you will also need to reduce the compression so that a larger amount of boost can be applied. ie you cannot run the standard compression. and finally a dump valve or re circ valve might be a good idea as this will prevent killing the turbo.

Just my thoughts.

[Killerwhale]

I was looking at the build pics on the German website.
If im right looking at the pictures,the gasses flow from turbo to plenum to carbs. shouldnt it be turbo to intercooler to plenum to carbs. If you dont have the intercooler you will get major det and melt the pistons,ie too much heat, you will also need to reduce the compression so that a larger amount of boost can be applied. ie you cannot run the standard compression. and finally a dump valve or re circ valve might be a good idea as this will prevent killing the turbo.

Just my thoughts.

It´s kinda "standard" in Sweden running a tad lower comp and E85 (85% ethanol & 15% petrol if you don´t have it)
....runs much cooler and with a bigger bang if jetted/mapped properly!
....One thing that would be neat is a valve on the plenum wich closes at a specific pressure so the motor can act as a suction enjun until pressure is up to let´s say 0,5 bar. (but i guess that would be hard with carbs)

[peasngravy]

can you give more details on (GTTI turbo which is an RHB51 ) whats it off ? how old is it ? petrol or diesel ? to be honest 6lb is not so much but probably ok , i dont know ,,but to give you some idea we ran a 45mm wheel at 110,000 rpm and we got 19lb of thrust out the back ,but at 120,000 rpm you get a lot more thrust, we got 30lb of thrust ,, balance is CRITICAL at those revs ,and Ive just remembered at self sustain , (thats with the starter removed and its now running on its own) its now at 30,000 rpm it is developing about 6 to 8lb of thrust, you say you have done this before have you seen the variable nozzle guide vane if you can get a turbo with this on and somehow link it to your bike this will give more thrust at the bottom end as it alters the diffusion angle on to the back wheel ,, i seem to remember the Honda cx 650 had a turbo and it gave about 5lb of thrust ,,it was useless

judging by your comment i think you think im putting a turbine on the back of my bike as in jet turbine and using thrust to propel me. nope im going to turbo the bike. as i said before im only runnig low boost at about 5 -7 psi so i can run standard compression with the help of a little box of tricks my mate has knocked up which retards the ignition timing when on boost and 98ron fuel. im not hoping for big power gains its the engineering side of it and the fact it should sound outstanding.
with only running low boost i will not need an intercooler but will fit a dump valve to help with any turbo lag and the fact that the ignition timing has been retarded.

[Killerwhale]

can you give more details on (GTTI turbo which is an RHB51 ) whats it off ? how old is it ? petrol or diesel ? to be honest 6lb is not so much but probably ok , i dont know ,,but to give you some idea we ran a 45mm wheel at 110,000 rpm and we got 19lb of thrust out the back ,but at 120,000 rpm you get a lot more thrust, we got 30lb of thrust ,, balance is CRITICAL at those revs ,and Ive just remembered at self sustain , (thats with the starter removed and its now running on its own) its now at 30,000 rpm it is developing about 6 to 8lb of thrust, you say you have done this before have you seen the variable nozzle guide vane if you can get a turbo with this on and somehow link it to your bike this will give more thrust at the bottom end as it alters the diffusion angle on to the back wheel ,, i seem to remember the Honda cx 650 had a turbo and it gave about 5lb of thrust ,,it was useless

judging by your comment i think you think im putting a turbine on the back of my bike as in jet turbine and using thrust to propel me. nope im going to turbo the bike. as i said before im only runnig low boost at about 5 -7 psi so i can run standard compression with the help of a little box of tricks my mate has knocked up which retards the ignition timing when on boost and 98ron fuel. im not hoping for big power gains its the engineering side of it and the fact it should sound outstanding.
with only running low boost i will not need an intercooler but will fit a dump valve to help with any turbo lag and the fact that the ignition timing has been retarded.

And THEN i can buy it from you????

[peasngravy]

suppose everything has a price

[Quan-Time]

theres a few grades of inconel. If its "kicking around" id suspect its 625. Yes its good, but you want a min of 718 for its heat properties. And you obviously know that its incredibly tough to machine. 718 being the same stuff that jet turbine blades are made out of.

Dont know if id really use a daihatsu turbo. But if you plan on using stock TRX motor, i guess it could be the item to use.

If you, as you stated in your first post, done a few vehicles before, you should know about the tricks / requirements of what is needed to turbo a vehicle. You should also know that aspirating anything, even a V-twin motorbike, is mainly reliant on your airbox setup. Theres a huge number of ways of doing this, but your best bet is to reproduce your airbox in alloy / steel. Much like the link that KW (killerwhale) linked previously.

As a guide, ill state that you should really look into (but obviously you know these as you have turbo'd before, but for the benefit of others who might want to know)
1: fuel supply. You are possibly going to get some fairly big jets depending on boost. But the golden rule of 1/2BAR (half atmosphere, or ~7psi) should hold firm
2: oil. You are going to use ~500ml more oil, and its going to get fairly hot. So make sure you top it up accordingly and possibly have a oil cooler. Dont forget that the TRX has a wet clutch, so you are going to be passing that thru the turbo, you will need to accomodate accordingly.
3: Gaskets. Id be investing in either an o-ring block mod, or at the least a decent head gasket, and full head work (valve lap, reshim, new exhaust studs) and possibly new head bolts aswell.
4: Cooling MAY be an issue, but i honestly dont know. Id be keeping an eye on it. Doubt you will have to go to a bigger core radiator, but you never know.

Thats the VERY basics covered. See how you go. And as always, post pics when your on your way

I have my reservations on power, i dont think its possible to get much over 120hp on a stock motor, 145 - 150hp if you really know what your doing / do some heavy mods to things. Your going to be very deep into "broken-stuff valley" over the 130hp mark id suspect. But hey, could be fun finding out everythings limit !

[tigkid]

Have you read any of the books which are available on the theory behind turbocharging?
They normally give you the basics about how to size a turbo based on the size of the engine, its expected rpm etc.
From that, you come up with some basic flow figures which you then plot onto the compressor map of a potentially suitable turbo. Its then just a question of trying different maps until you find the one which is most suitable for what you are lloking for. If you have the figures, a friendly turbo supplier may well point you in the right direction of a suitable turbo.
If you have a reasonable handle on maths, the hardest part is getting access to the compressor maps.
I think your right about the T2 being too big for an 850 though. I'm told they will hit about 150 bhp tops, even though they make 115 to 120 on a Renault 5 turbo as standard (you'd never guess I've got one in the garage would you!).
Good luck, it sounds like it could be an interesting build.

[Bennybloke]

Evening all, first post since joining but seeing as I'm also 'blowing a TRX I figured this would be a good one to start with . I don't claim to know everything about forced induction and am of the opinion that anyone who says they do is quite frankly lying, but on the other hand I'm no stranger to it. I run a 300hp supercharged 'busa as a daily bike and have a hand in the build of my boss's 450hp turbo busa (which for the info of the guy whose name I can't remember at the mo, is perfectly smooth and useable, as with anything it's just down to good design and setup wether it'll work nicely ) and we're currently rebuilding a turbo'd R1 for a mate of ours after another shop ripped him thousands for something that looked like it had been converted with only a bread knife and a sledge hammer...
Anyway getting back to the original topic, there are a few things that I've already stumbled across that you'll have to deal with. Firstly the standard fuel pump is only fit for the bin if you're going this route, lack of any kind of fuel pressure not withstanding, dont be tempted to try and get away with it because the first time it boosts up the pressure'll go straight down the vaccum line and just shut it off completely. On the subjects of oil feed and return, there's a pressurised external gallery behind the block on the left hand side which is looking like the best bet to me at the moment, and for a return I'm wanting to use the bike's own return pump to draw oil away from the turbo but I'll have to have a proper look into this later as I'm still in the process of getting the turbo actually mounted. But even if that doesn't work, there are companys that make electric scavenge pumps that will do the job just as well.
The guys are right about compression, drop it or you WILL blow your engine to pieces, even as little as 2 psi of boost is an engine killer. (As an example the guy who originaly built our mates r1 did a piston, a bore, and a headgasket on seperate rebuilds and dyno runs) Personally I'm going to drop to about 9.5:1 and run at 7 psi of boost. This will be done by way of a copper headgasket that I'll be making myself, the thickness of which I can't remember off the top of my head (there's a folder full of all my mathematical scribblings in the big box of bits in the workshop lol). Providing you drop the compression though you should be able to run the rest of the motor stock (my Busa's running at 16 psi with nothing more than a barrell spacer to drop the compression and a set of APE cylinder studs, and they were only used because we had them lying around.)

As for my bike if anyone's still reading I'm using a turbo from a 1.7 litre vauxhall diesel, twice the cylinders, twice the capacity but a third of the revs. I's a physically tiny unit, looks like a model next to the GT on my boss's busa, but after a looong time with a pencil and calculator, it should start boosting from 1500rpm, have a fat bottom end and posistively bulging midrange and produce around 115hp at 6800, not a massive amount of power but the quick spooling and 90ish lbsft should make for a brilliantly grunty, smoothly delivered power band that isnt going to over rev those wide flat pistons and heavy rods, should be just as reliable as stock and ride brilliantly in the real world.
The best laid plans of mice and men eh? I'll start getting some pics together once I've got the turbo completely hung in place, and will be interested to see how your project comes along too .

Ben

[slow codger]

Welcome to the world of the TRX! whereabouts in it are you?

I have no idea about mounting a turbo on a TRX, or anything else for that matter! So I shall watch this thread and learn. Plenty of pics needed.

Dave E