Hello, im Evangelion and new to the forums, for the next few months you will be seeing alot of post from me with questions after i have used the search functions of this board and //www.google.com extensivly.  :mrgreen:




Im just formulating my game plan at this stage, but im taking specific classes right now that will help me along the way.

I plan on doing this to a 2004, id like to keep the full fairing look so im willing to make sacrafices.

Basic componets...

Exaust to turbo piping (the part i fear)
turbo (Preferably a GST from an eclipse?)
Straight pipes exaust from turbo (dont plan on making it street legal)
Intake piping from turbo into carbs (the part i fear 2)
Intercooler (thinking about skipping it, im just trying to make a working model not a race model. Later when i have a base to work from ill introduce a side mounted intclr)
BOV high flow (Directly into atmosphere?)
Wastegate (Im under the assumption its already on the turbo)



The goal:
To create a 2004 GS500 that is capable of creating and sustaining 6 pounds of boost all the way to the red line while making the system compact enough to keep the full fairing.

The problems im worried about:

Id have to have the piping made coustom, im expecting that to be the hardest part because of the stress they will have to be able to withstand aswell as having it fit under the fairings.

The honest need to have an intercooler when only running 6 pounds of boost with pump gas?

How does a carbed engine force the fuel into the cyclinder when its fighting 6 pounds of air, in the injected cars i work on the injectors have to be replaced with more forceful injectors that are rated above the amount of boost you plan on using.

Keep in mind ill be taking many college classes, so realisticaly ill be answering my own questions in about a month but id like input from you people who have/are atemping this.




What problems are you running into?

Someone on here did this already, use the search function and I'm sure you'll find the info. IMO your biggest problems are going to be fighting heat (the GS is air cooled which is one strike already), and working out the correct fuel jetting. Remember the GS is jetted lean stock, which makes the bike run a bit hot. Lean jetting + air cooled motor + non-intercooled turbo = boom. Especially if you're planning on keeping those fairings. Where are you going to mount the turbo without melting your plastic?

AS far as forcing air into the carbs, I would think feeding the airbox would be the most logical way of doing this. WIth a filter on the turbo intake, I'd plumb the forced air into the airbox inlet and lose the airbox filter.

Then again, I've never put a turbo on a bike. SO what the hell do I know?

pm werase643 I know he had some experience in this area,   I am pretty shure that the turbo off a eclipse is going to be way too big to make it work,  Yamaha SECA's had a turbo option if i remember right, and your going to have to go with fuel injection, as carbs work on manifold vaccum and turbos work on a pressure system.

I think werase643 actually has a seca turbo and manifold for sale too.

Yeah... sooo... the money that you'll be dropping into the turbo plus the money you spent on the bike would have equalled a real sportbike.  

If you're doing this for performance... see above.
If you're doing this just because you can.. then cool! and good luck.  

Just remember- the last guy that pulled it off was a mechanical engineer-

he was not a mechanical engineer....He was a ME student( grad student i think)....who worked his but off

better money spent on an older bike and a smaller turbo
another option is to get one big carb and install it in front of the turbo and pipe everything into the intake boots....keeps you from having to pressurize the carbs
6 # is not very much pressure
also need a wastegate....variable is good
to help with cooling....BIG oil cooler

and yes i have a TINY!!!!! turbo from a seca 550 turbo and some of the piping
spins freely
$150 +
this is what i paid....this is what i want.
else it can sit in the basement and rot a few more years
til I get off my butt and turbo a DR650 THUMPER!!!!! :mrgreen:  :mrgreen:

So youre saying theres no problem in having the carb before the turbo? that the mixture can run all through the turbine and to the two intakes and still be fine? seems like youd have to put on like 190 pilots and like 70 mains to get a half way decent mixture.

Quote from: gregvhen on January 14, 2010, 10:47:12 PM
So youre saying theres no problem in having the carb before the turbo? that the mixture can run all through the turbine and to the two intakes and still be fine? seems like youd have to put on like 190 pilots and like 70 mains to get a half way decent mixture.

what you just described is called a pull-through set up and it works on superchargers very well. in fact most carbureted roots or screw type superchargers are pull through. even some centripital (similar to turbo in boost function) setups are pull through. the problem with a pull through on a turbo is heat, turbos are HOT and it can catch the pre mix on fire in the piping (bad).
the preffered set up on a turbo is blow through. with blow through you mount the entire carb in a air tight box and feed boost to the entire box.

carbs work on pressure differential, they reference outside pressure through a port on the carb body and the lower pressure going through the carb pulles the fuel out through the jets. Sooo... if you put the entire carb in a boosted box it refferences the boost and the slightly lower pressure air moving through the carbs will pull fuel through the jets. but yes its less efficient because with boost the air moving through the carbs is almost the same pressure as the pressurized box and thus the refference signal, so you have to use huge jets.

I seriously doubt a blow through set up will fit under the fairings. also an intercooler is almost a necessity unless you pull tons of timing and run super rich, both of which would kill power. basically without an intercooler the power gains would be very minimal.

this post has risen from the dead!

I almost forgot, the gas tank would also need to be boost referenced and sealed or else you will blow fuel out of the gas cap.

My, the grave dirt and maggots on this thing. Must be looking for brains to eat.

In one case of commercial production, blow through, sealed carbs (not carbs in a box, but carbs sealed up and the atmospheric parts connected to the intake air) and a fuel pump (gas tank vented to air as usual, pump provides the pressure for the fuel.)

And if you really want to play, grab a truck or trailer, come to where MA, VT and NY intersect, and make me an offer. While I'd love to get it all restored and stuff, the fact is I have too many projects and could use the space it takes up. Clean title. All there, complete. Fairing is off at the moment and has quite a few bits that need work, seat cover is shot, the sort of old age issues any 28 year old bike is subject to.

http://gstwins.com/gsboard/index.php?topic=42199.msg485636#msg485636

I'd like to know if you can use megasquirt and convert it to single injector fuel injection 

Im all for modifications just look at my sig. but I also believe there becomes a point when its just easyer cheaper and more efficient to get a bigger bike. a gsxr600 will make as much or more power as a turboed intercooled big bore camed fuel injected gs500 can possibly make on race gas.

having said that I think a turbo gs500 would be a cool project, costly and hard, but cool. and I would love to see progress via pics and vids posted here for us dreamers.

Quote from: Evangelion on July 19, 2004, 10:35:30 AM
Hello, im Evangelion and new to the forums, for the next few months you will be seeing alot of post from me

.......so what happened? Did reality suddenly kick in 

I have found that Turbocharging motorcycles from scratch can be compared to Shagging women...Those who like to talk about it a lot very very rarely get round to actually doing it  Its the ones who DONT talk about it that are the experts.

i like to learn about the process but will never have the funds to do it. so does that mean i enjoy sex-ed class but can afford condoms?   

im stupid and cant find out how to delete a post, why am i commenting on a 6 year old thread