e.g. drill R1 carb main jets out to 1.8mm should be pretty close for a 2ltr.
http://www.affordablegokarts.com/Drilling%20Main%20Jets.php
[Edited on 26/9/09 by cd.thomson]
I understand that bike carbs are better for performance due to there design, do you need to get them re-jetted or anything or is it a case of fit and fiddle around/balance till it runs right?
Bike carbs will need rejeting most of the time
what engine / carbs are you using
Jacko
Not using any yet, weighing up pros and cons, suppose manifold will be a pain.
You could be lucky and find that it's okay but it's unlikely. If you don't re-jet them (unless you are just plain lucky) you'll find that the engine won't rev properly and you'll be down on power and MPG... I certainly think with a bike carb conversion it's worth assuming you'll end up paying out for some new needles.
be careful if you buy one of the ready to go setups..
a friend recently bought a set of carbs with manifold and filter all jetted for a 2.0 pinto.....
had it on the rollers friday and they aborted the run..
said it was running dangerously lean and would damage the valves/piston on no.4 due to the heat....
he now has it rebooked in with a quote of £220 to rejet it...
[Edited on 26/9/09 by gavin174]
£220 to drill out the main jets? there are guides to doing it in your own garage on the net!
e.g. drill R1 carb main jets out to 1.8mm should be pretty close for a 2ltr.
http://www.affordablegokarts.com/Drilling%20Main%20Jets.php
[Edited on 26/9/09 by cd.thomson]
quote:
Originally posted by gavin174
be careful if you buy one of the ready to go setups..
a friend recently bought a set of carbs with manifold and filter all jetted for a 2.0 pinto.....
had it on the rollers friday and they aborted the run..
said it was running dangerously lean and would damage the valves/piston on no.4 due to the heat....
he now has it rebooked in with a quote of £220 to rejet it...
[Edited on 26/9/09 by gavin174]
Bike carbs are very similar as SU's, they are more modern and are easy to set up.
I banged a set of ZX9R carbs on my zetec and went for SVA.. the passed OK then I went to Blogg Brothers to get them set up correctly and managed 40mpg
out of them.
I can get my zetec to tick over smoothly at 600rpm as well.
Steve
they are zx6 i believe....
i have looked on another website and looked like there may be four vacuum pipes that need blanking....
will check tomorrow..
anyone any experience of zx6 carbs..
Frankly, if you put ANY new carbs on an engine - whether they're bike ones, Weber DCOEs, or SUs - you will have to get them tuned to get the best out of them.
quote:
Originally posted by gavin174
be careful if you buy one of the ready to go setups..
a friend recently bought a set of carbs with manifold and filter all jetted for a 2.0 pinto.....
had it on the rollers friday and they aborted the run..
said it was running dangerously lean and would damage the valves/piston on no.4 due to the heat....
he now has it rebooked in with a quote of £220 to rejet it...
[Edited on 26/9/09 by gavin174]
ZX6 carbs are easy to set up. I have them on my Zetec 2.0. I drilled the mains out to 1.6mm and moved the needles a notch to get the mid range mixture
right.
Mine hasn't been on a rolling road, but I used a wideband O2 sensor to check the mixture whilst driving.
I get about 40mpg.
Stu
it is the gbs set up he has...
had it on the rollers where there do bikes and cars..
charged £40 for a "power run" to see what it was like....
they stopped run half way through and said they would go any further.
and refunded £20
running "dangerously" lean.
have seen a post on rhocar that says about 4 vacuum tubes need blocking. need to check tomorrow.
does anyone know if the same applies for zx9r carbs? it would appear not from coozers post..
Just my perspective, here, but.
I hate bike carbs.
I had the standard 40mm on my gsxr1100. I struggled to get it through SVA (even though its pre-94) and struggled to tune it nicely. You end up
spending money on dynojet kits (loads of money for nothing of any real use in the case of the GSXR1100), and generally buggering around adjusting fuel
levels and such.
Its a pain in the bum, and you car will smell of fuel, as the carbs will either leak (the problem with 15 year old seals), of just vent off all the
fuel in the summer.
Fuel injection is the future (okay it was the future 20 years ago). If you megasquirt with an O2 sensor, then you can set it up dead easily. Total
cost isn't bad either.
Just my perspective,
Matt
quote:
Originally posted by matt_gsxr
If you megasquirt with an O2 sensor, then you can set it up dead easily. Total cost isn't bad either.
Dangerously lean from GBS, i would imagine might be an air leak somewhere round the rubbers/manifold. Might need a spray around the suspect areas with
wd40 or gas whilst running the engine to see if the engine speed is affected.
Having said that, I think bike carbs maybe female in gender. They need a lot of attention, can be very expensive to find out what makes them tick, and
reserve the right to have the final say
You dont need to block the vacuum jets. Its the air bleed holes you need to do. If you search the site theres piccies of the hole u need to bung up.
If you get a dyno jet kit they come with the proper brass bungs but arnt cheap.
My 1.8 zetec with zx9 carbs iv got 155 mains and standard non adjustable needles. goes well but not been on a rolling road yet. I really wanna
take it to boggs but theyr too far away.