Bike Carbs and a turbo? Greasy!

pretty exciting build, have been thinking of something similar. How do bike carbs hold up against boost?

Not very well, the seals and diaphragms just disintegrate.

Is that a problem you've had Max?

looks smart :)

Nah only kidding lol. Its not a differential pressure on any of the seals as the each side of the components are pressurised,

So in theory, they don't see any stress other than a small amount of compressive.

Been reaaaaal lazy the past few weeks. made a start on the bay sort of yesterday, wish i hadn't lol. Got the plenum now, just sent it off to have a pipe welded on for the boost hose to attach too. inlet should be coming back with it, just having some vacuum tapins welded on for the amethyst kit.

Quality project - looking forward to seeing how it performs.

Is that plenum tapered?

Nope.

I'm liking the looks of this! Bike carbs and a turbo should be sweet!

Need some motivation to carry on! having no garage sucks ass lol.

Had planned to borrow a mates compressor and paint gun and do the bay properly but i really cba anymore so gonna finish off tidying it up, etch primer and rattle can it and throw some lacquer down. So lazy lol.

gotta weld in a turbo drain pipe which i also cba to do, might fit a windage tray if i can be bothered as well.

Gotta find some CBR600-f4 carbs as the ones i have aint gonna work, and make a manifold then i think the engines fully done, gonna replace both crank end seals too actually they look ugly.

why am i so lazy. someone motivate me!

ha... I know how you feel.. been there... but the motivation does come back. :)

Dude i did all my work on mine without a garage 😂 Man up its worth it

You also have a benchmark to beat of 176hp let beating Buxton be the motivation

Different engine to mine jim, so abit different, aav with a k03 should make similar power, sceen a g40 injection aav make 173bhp at a bar of boost. But then carbs might flow the air better then g40 injection.

Would the bike carbs not be better than the r5 turbo carb, some bike carbs apparently take boost very well

Also why is everyone always calling me Jim haha, I really need to change my username. I have John on both by build threads haha. There isn't even an I in my user that's my initials [emoji23]

Haha oh yeah! Sorry john 😂

gets abit complicated but 4 venturis is gonna flow more air then 1 venturi, bike carbs need abit more work to seal the float bowls ect were the r5 carb is allready sealed and made for the job, each to thier own, i cant balance carbs ect so i stuck to a single carb 😂

Balancing them is a piece of piss chris! literally bike carbs are easier than life it self lol. tried to update the first page of this thread for engine specs etc but can't remember how to edit the first post? theres nothing obvious that says EDIT ME lol.

I'm using a G40 cylinder head with some head work, carbs obviously and mappable ignition too. Keeping CR at 9.5:1. No idea how its gonna fare but its an old 8v so it'll be fine! When i blow the head into outer space I've got plenty spare !

Got a shitty mk2 golf to sort out before the polo, and moving out to deal with! main thing is painting the bay and once thats done its just re assembly lol

9:5:1 will be fine👍, click on the post then under it push edit? if you still cant do it i can edit it pm me if you want me to change anything.

Yeah so long as i don't get greedy with boost lol. don't think it'll see the road this year so gonna throw more money at it i think. Got a k04 lying around waiting to be used haha i think ill throw that on!

What are you doing for a pitot tube? Only asking as you'd need to keep the fuel pressure to all carbs above boost pressure to avoid fuel not getting to the engine.

Same with diaphragms and fuel vents. I can't see the plastic fittings being too good as the O-rings are tiny in them - i'd wanna make ally replacements with beefier O-rings.