how to build a blowthrough carb for your turbo bike

[Adelphos]

Hey could you help me to install a turbo to a 1941 indian scout engine?

[cggorman]

I got that, and a wide band O2 meter. once I had it tuned up, I took the wideband off the bike.

What setup were you using for your wideband? I'm looking at putting together a portable wideband to help tune a couple carbed NA bikes in the stable.

[Blakeslee]

Turbonate. I'm in the process of putting a turbo on an sr250 but I need help understanding what to do with carb set up. Everything is hooked up and conected turbo wise. Just didn't know if you had any extra advise to what you've already said being is the motor is so small.

[FLASH1970]

Am I on the right track?

[FLASH1970]

What setup were you using for your wideband? I'm looking at putting together a portable wideband to help tune a couple carbed NA bikes in the stable.

I've installed and used a couple Innovate LC-1's when tuning cars with a DB gauge (just has a number readout) and the XD16 gauge (number readout and various color LED's along the outer edge lit up based on what the AFR is). But for datalogging and tuning I was able to have it hooked up to a laptop on the passenger seat... Can't really do that on a bike. lol. I believe the LM-2 can log multiple channels (RPM,AFR...) and store the data. And the LM-1 can as well but you need add on harnesses. I have also been looking into the Zeitronix ZT-2 that can log 4 channels of data at once. But, you have to buy a thumb drive add on to save the datalogs for analyzing on a laptop. Hope this helps.

[81HondaBobber]

When boosting the bikes did you have to change engine internals like how you do in cars? Also do you need all the gauges/regulates like in cars as well(boost pressure, fuel pressure, motor oil pressure, turbo oil pressure?

[quadrazer]

Could you possibly PM me some photos of your carb modifications? For some reason, they won't open for me on here.

[OlDirtyDoug]

I can’t view the photos for this walk thru, can you send them to me by chance?

[Tattooo]

I can’t view the photos for this walk thru, can you send them to me by chance?

You do know this thread is basically 8 years old right???

[Tmoney88]

now here is the key to the kingdom that makes this whole mess work right. i installed a pitot tube into the charge pipe with a flared end directly in front of the compressor outlet. now tie the hose from this into a y that feeds into the pressure port you put into the side of the carb, and the fitting on your boost referenced fuel pressure regulator. what this does is the flared tube creates a restriction in the intake path and the higher pressure generated is carried to the float bowl and fuel pressure regulator creating about a 1.3 to 1 float bowl to carb throat pressure differential causing a self enrichening condition under boost that will keep your pistons from having a thermonuclear malfunction. on my bike i'm making right at 10psi so i limited my total timing at 8 degrees shy of the stock max, it's been a couple of years since i set it all up, so i don't remember the exact numbers.

I’m interested in this setup, but can’t open the attached pics, can you send the pics another way?

[KrisCarr]

I’m interested in this setup, but can’t open the attached pics, can you send the pics another way?

I found a wealth of information on blow through turbo setups on google. I'm thinking about doing my Gl1100

[Guest]

i'll try to list everything in the right order as the pictures

the first thing you need is an electric fuel pump, i use a frame mount pump from an 89 f-150, they are available at any parts chain for about a bill. you can also see the fuel feed port i added to my tank in this picture.

you'll also need a filezilla uc browser rufus good quailty return style boost referenced fuel pressure regulator, i use an aeromotive since i've had great success with them on my race cars

, i guess it goes without saying that you'll need a return port in your tank as well, i used the stock pickup location as a return port.

next you need to seal all the atmospheric vents on the carb and drill and tap it somewhere above the fuel level, i built a 4 into one manifold and used an old zenith i had.

i've put almost 12000 miles on it and ridden it all over hell and creation with no issues other than getting some trash in the needle and seat outside of slidell la once.