R1 Carb conversion for a 205GTi
- Thread starter Pugmania
- Start date
Not myself, but once upon a time it was a pretty popular thing to do, especially in the UK. I did put R1 carbs on my 504, however...nice smooth power.
Talk to Bogg Brothers https://www.boggbros.com/
They fabricated my inlet manifold and airbox, and did a really top job, too.
You'll probably want to pull the carbs apart, replace all the o-rings, which is easy and inexpensive. SKF will help you size them up. Needle and seat kits may set you back a bit from Yamaha, but it's something you'll want to look in to... and gaskets for the bowls etc. I've seen on ebay.
The carbs only want to see about 4 psi max fuel pressure, so get a low pressure fuel pump.
Make sure you have a good Wideband AFR for tuning, and upsize the main jet from, I think it's around 130 or smaller on an R1, to about 155 or 160 on your car. If you can, source the carbs locally so you get adjustable (hopefully) needles. Ones from the USA don't have adjustable needles, as I found out
Idle jets would need to be enlarged too, but most people don't bother...but only so much adjustment can you get from the screw before it bottoms all the way in, or falls out on the floor.
I think you're going to have to trick the 205 GTi computer in to running ignition but not injection somehow...or use an aftermarket computer. I've got no experience with 205's, so I'll let someone else chime in...
Talk to Bogg Brothers https://www.boggbros.com/
They fabricated my inlet manifold and airbox, and did a really top job, too.
You'll probably want to pull the carbs apart, replace all the o-rings, which is easy and inexpensive. SKF will help you size them up. Needle and seat kits may set you back a bit from Yamaha, but it's something you'll want to look in to... and gaskets for the bowls etc. I've seen on ebay.
The carbs only want to see about 4 psi max fuel pressure, so get a low pressure fuel pump.
Make sure you have a good Wideband AFR for tuning, and upsize the main jet from, I think it's around 130 or smaller on an R1, to about 155 or 160 on your car. If you can, source the carbs locally so you get adjustable (hopefully) needles. Ones from the USA don't have adjustable needles, as I found out
Idle jets would need to be enlarged too, but most people don't bother...but only so much adjustment can you get from the screw before it bottoms all the way in, or falls out on the floor. I think you're going to have to trick the 205 GTi computer in to running ignition but not injection somehow...or use an aftermarket computer. I've got no experience with 205's, so I'll let someone else chime in...