Turbo TRX

[Artsi_L]

Supercharged MotoGuzzi in Finland. Click away... http://hogsden.dyndns.org/~jsavola/ahdin/44.html

I saw this one few years back at Hot-Rod auto show, the lot had two off Guzzis done this way. I'll browse my home PC hard drive for pics at that show. I'll post 'em up if I find any.

Cheers.

[Quan-Time]

Turbo VS supercharger... the age old story. Turbo "lag" is a made up thing.. its basically what happens when you short shift and you have no power. You are not in the gear / rpm you should really be. many people bitch about this being a "flaw" in the way turbos are designed.
Superchargers require a BUCKET load of power to work. they are in the region of 30% absorbing. So for every 100hp you want, you have to produce 133hp to get it. Thats just the inherent nature. Saying that, you get power whenever you want. Which is a nice thing.

14psi on a bike isnt all that hard. Id like to see what other engine mods he has done to get it. Say the bike is 90hp stock (being generous here) with a nice exhaust and a rejet of the stock carbs. 14psi would yield him to about 140hp as claimed fairly easily. 14.7psi is 1bar (which is what we are standing in). so if he was to cram 14.7psi into the engine, he is effectively (on paper) getting 2x the air and fuel in, which gives double power. take into account heat, pumping losses, etc.. 140hp is right on the money id guess.

Id be interested to know what RPM the boost comes on. Im guessing its in the ~5200rpm+, probably closer to 5600rpm. You are not really going to notice any more power from city riding unless you really start twisting that throttle. After a full boost and release, if the revs drop under ~3800rpm(ish) you will notice a bit of negative torque as you will get a touch of vacuum thru your lines, depending on what he has done to compensate for that. You can easily overcome this if you use your wits.

My personal choice would be to use ~4 / 5psi of boost. Say phuk, honky, kwhale, bobtrx, anyone with more than 95hp at the wheel, if they used a smallish turbo, but only boosted to 4 or 5 psi, they would get delivery about 2200rpm, and see about 20hp. This is totally usable without being insane. its also not stressing the internals hard, and shouldnt stress the turbo out running boost all day. Only thing i would advise is possibly extra oil, or possibly a small cooler of sorts.. Doesnt have to be big, just has to be exposed to air, that should be enough.

How many people ride the trx under 2500rpm ? not many. so at idle, or slow moving traffic, the turbo isnt doing anything, but once you actually start moving properly, your set. its a much more reasonable usage of power, your economy would be almost identical surprisingly, and its still quite cheap (compared to a charger / nos setup).

And for the record, i strongly believe that with correct setup and work, 160hp could be made on 12psi on a TRX. Altho dont quote me on that, but im very confident on those numbers.

[Killerwhale]

And for the record, i strongly believe that with correct setup and work, 160hp could be made on 12psi on a TRX. Altho dont quote me on that, but im very confident on those numbers.

Agreee fully!

[Artsi_L]

A side note.

In automotive world there are myriads of motorsports and classifications. This one particular "auto-cross" -class I am referring to, had 2WD and 4WD rally spec cars competing on a twisty 3 to 4 km long tarmac course. Some classes demanded for naturally aspirated engines, and some allowed use of a turbocharger.

I remember some of the competitors wondering how can they post better lap times in a highly tuned 2-liter naturally aspirated car, when comparing over to previous years experiences in a 2-liter turbocharged cars. Many drivers noticed the very same phenomenon.

Could it be, that driving/riding on the very edge of tyre adherence, the naturally aspirated engine is more predictable, more tracktable, in power delivery?

Yes, turbocharged applications are winners in a straight line, and are also good for cruising through the twisties - but how about in a hard core racing circuit?

[Corners R Us]

http://www.youtube.com/watch?v=3rr-kkJ5UAg

How to make your R1 into a poggo stick !! Can't see the point myself or riding it like this individual chooses too ! He must have an account at his local dealers for fork seals too!!!!

Supercharger seems a better, more controlled power to me...if you really need that on a road bike that is! Personally I find my humble 79bhp or whatever a stock TRX puts out more than ample. Equally its a humbler when you get the better of a litre bike on the track .

Corners

[Quan-Time]

remember that the boost isnt comming on til what appears to be 7500rpm. Thats obviously a fairly high amount of boost, and with compression already over 11:1, its fairly peaky. Its why it wants to wheelie. Turbos help engine revs peak faster when they are on. Also, the heat that thing must produce would be scary. Its why many people tend to want 8:1 on turbo engines.. Better response, less wear, easier spooling, less heat, less work on the intercooler (if you have one, most bikes have water injection) etc..

As ive said before, it all comes down to what you want.

I quickly ran some numbers, on a 850cc engine, if you could intercool below the point of saturation, and on 10.5:1 comp, and 98ron fuel, if you fiddled with the engine and set it up correctly (cam, fueling system, change valves, yadda yadda), its possible to get close to 200hp on around 16psi. Obviously i dont have a bench mark to compare to, But with what ive seen of the engine, piston speeds and what not, its possible. Id suspect most of the internals could handle it.
Id actually fear the gbox having huge problems before anything else. It would most likely blow 2nd gear id think, or pop out of gear under heavy load and revs would skyrocket, leaving you with a game of hide and seek with your valves which would be shot out of the engine at warp speed. That or melt into the pistons.

[JW-TRX]

I recon that guy will have to rebuild his engine very often. Don't think the motor was mode for something like that. It's like putting a turbo on n 1300 car...Who does that!? Just get yourself a 2.8L V6 or something...

I like the engineering that went into this project.

[Killerwhale]

I recon that guy will have to rebuild his engine very often. Don't think the motor was mode for something like that. It's like putting a turbo on n 1300 car...Who does that!? Just get yourself a 2.8L V6 or something...

I like the engineering that went into this project.

MOST...that is most engine are fine with x2 on the HP....over that and it´s getting critical.
But as said and shown in the thread there are a swedish TRX wich i can report from soon.

[zod]

It's like putting a turbo on n 1300 car...Who does that!?

VW? TSI 1.4

[idl1975]

It's like putting a turbo on n 1300 car...Who does that!?

VW? TSI 1.4

And a supercharger... they put a g-lader on the polo in one of their many mad moments, if I recall correctly. A 1300 cc Mk2 polo, to be precise.

VW are weird. It's like their engineers were on an incentive scheme to develop the widest possible variety of powerplants. VW has more engine codes than Dog. I think there are whole databases just so you can figure out what's under the mess of wiring in your rust-eaten Wolfsburg tin can.

Personally I have nothing (other than complexity) against FI engines. I just don't really want, myself, a 160hp road bike. The 80hp TRX already outruns the rest of the traffic around my neck of the woods, and they don't pin medals on you for being fastest down the straights on track days.

[Kayla]

... and they don't pin medals on you for being fastest down the straights on track days.

[cough]Run what you brung[/cough]

[JW-TRX]

It's like putting a turbo on n 1300 car...Who does that!?

VW? TSI 1.4

A yes...well that is something else...

What i'm talking about is the guys over here with their 1300 opel corsa's that put a free flow pipe on and thinks they added 15Kw and the GT stripes down the center another 30Kw...LOL

The point I'm trying to make is instead of trying to add all that power to a bike, just go out and buy yourself a bigger faster one...

[Killerwhale]

It's like putting a turbo on n 1300 car...Who does that!?

VW? TSI 1.4

A yes...well that is something else...

What i'm talking about is the guys over here with their 1300 opel corsa's that put a free flow pipe on and thinks they added 15Kw and the GT stripes down the center another 30Kw...LOL

The point I'm trying to make is instead of trying to add all that power to a bike, just go out and buy yourself a bigger faster one...

They don´t do a bigger faster TRX mate! (i wich though)

[TonyDevil]

some people just like modifying things, gotta respect the engineering skills of those doing it themselves

but i agree, if its just a bigger faster bike you want go buy an R1 (or an SP2 if u want a twin)

[Kayla]

They don´t do a bigger faster TRX mate! (i wich though)

What about sticking an MZ 1000S engine in a TRX. It could probably be persuaded to run on FCRs using early TDM electrics (180 degree crank). Just a thought...