I am underway with my locost DIY EFi conversion. Construction of the inlet with the original port injectors is going well.

TB's are off a CBR1000RR4/5 and have both TPS and a MAP sensor on them.

Q: Can MS-II use the elkectrical signal from the MAP or does it only use the actual vacuum from the inlet?

Steve

not 100% but im pretty sure its vacuum

Megasquirt normally uses it's own inbuilt vacuum sensor, but there no reason it couldn't be wired to an external one. The main issue would be ensuring the scaling is correct in the firmware.

Yes, uses vacuum pipes to built in MAP but can also use TPS or there's a setting called hybrid that can use both the Vacuum pipe/MAP and TPS - because of instability when Idling I think.

see here link

[Edited on 30/9/09 by big-vee-twin]

So, from my understanding I'm better of wiring the TPS in for load and let the vacuum go to the pressure regulator?

I'm new to all this, haven't got an MS yet but currently have a lot of hardware to make a system so I'll be asking some configuration questions atm.

Thanks,
Steve

Throttle bodies can be tricky to get a really useful MAP signal from, so many people use Alpha-N fuelling which just uses throttle position to determine engine load.

However if you have the option it would be worth plumbing the MS into the existing MAP pipe to see how well it works. Alpha-N isn't able to compensate for changes in barometric pressure, and is heavily dependant on an accurate and repeatable throttle position sensor. Speed-density is nearly always the best choice if it works for you.

MS2 allows you to combine both Speed-density and Alpha-N fuelling, though this is more for engines with really poor idle quality due to cams, not sure how useful it would be for ITBs.