hi im fitting my mj today,
i have a set of zx9r carbs,
now can i use the vac off of them?
or should i go off the manifold?

i have asked on the mj furom but it takes a little bit for somone to get back,i was hoping somone here might know.

thanks

jamie

it comes off the manifold. theres a guide on the megajolt site to show the best way. recommends taking a feed off each runner, joining together in a junction box then on to MJ.

don't your zx9r carbs have TPS? i thought they all did. would have been better to go with TPS i'd have thought?


http://www.autosportlabs.net/MJLJ_V4_vehicle_installation_guide

half way down

[Edited on 19/6/09 by blakep82]

Have the carbs not got a TPS? That would've been the preferred option.

My understanding (I do stand to be corrected) is that you'd need to take an outlet from each of the carbs or inlet manifold tubes, and connect them back into a single pipe to attach. This is based upon the OE manifold for the car having all sections of the inlet manifold connected together through a single throttle body with a single offtake for vacuum.

Hope that makes sense!

Here's how I did my ZXR750 carbs, works fine too.
Rescued attachment DSCN0858.JPG

My GSXR 750 carbs have a take off on each top cap and they work fine.

ok i have made a vac res but thats going to be used on a dellorto manifold for my turbo,i have drilled and taped the other 3 runers on that manifold,
but the manifold with my bike carbs on only have 1 outlet,as the lumanition broke down i want to get this up and running asap,
this is just for the mean time,
can you use the vac that comes off the carbs and the one off the inlet together into my res then to the mj????

Just join the carb vac outlets together using some tee pieces or into a common reservoir, use the small bore vacuum pipe that motor factors sell.Put a .6mm mig nozzle or similiar between the junction of them and the megajolt to act as a damper.
I ran a set up like this for a while and it worked quite well.
If you just want to get it working on the car quickly then you could leave the vacuum disconnected from the megajolt and set the load bins to the same figure and just use the RPM to adjust advance giving you a 2d map the same as a dizzy with no vacuum advance.
Paul.

quote:

---

Originally posted by jpindy3
ok i have made a vac res but thats going to be used on a dellorto manifold for my turbo,i have drilled and taped the other 3 runers on that manifold,
but the manifold with my bike carbs on only have 1 outlet,as the lumanition broke down i want to get this up and running asap,
this is just for the mean time,
can you use the vac that comes off the carbs and the one off the inlet together into my res then to the mj????

---