ITB mode....

[andy198712]

So,

Hello!

My setup is as follows,

MS1 2.2 extra
EDIS
GSXR 750 ITBs
2110cc

Currently on MAP for the VE table but looking to switch to ITB mode as I'm getting atmospheric pressure readings at small openings
EG 3rd gear up a light hill at 30mph probably under 10% TPS.... Just makes feeling a bit difficult, not impossible and runs well but just keen to try it out

Haven't really seen much of an idiots guide for it, any people tried it? How was it and how do you choose the switch points ect?

Cheers

Andy

[thedrew]

read over the MS manual section on it about 10x so you understand how the algorithm works.

then start looking into your log files and start playing around with your switch point curve. Set your switch point curve where you see your MAP signal start to not be a reliable predictor of load.

once your switch point is set, THEN you start your VE table tuning. Every time you touch your switch point your VE table will need to be updated.

[andy198712]

more reading required then

so do you use ups more for light throttle was my interpretation of it... as ITB have very little vacuum on tip in and light load i'm finding.... my VE table is nice i feel, but do need to create one for TPS controlled VE too?

cheers for the help

[thedrew]

how big are your TB's?

[andy198712]

Gsxr 750. There 40mm at the base and bigger at the top

[andy198712]

i did a dummy project today and made it in Alpha N, and then turned hybrid ON but couldn't find anything new? like switch points ect? need to find that bit i the manual think!

[andy198712]

well MS1 does not support ITB mode... so looks like i need to start looking for an MS2, be nice to upgrade to V3 for better res too which will be nice

[raul arrese]

I tried ITb mode and didnt like it , whats exactly is the problem ?? is your map sensor reading erattic at idle and small throttle opening ??

[andy198712]

why not?

i found with MS1 2.2 you don't get as bigger tables, and i was getting a very fine line between WOT and light cruise at times ect, i tried some one way valves(in 4 ports of the 4) and a restrictor valve at the end too... the valves didn't work as planned but the restrictor valve was good,

basically the main issue was small throttle opens(10% or less) say up a hill at 30mph in 3rd would put me at WOT kpa so it would be very rich

i think that, a chamber would make it nice and stable, and then i would need to have my map with gaps of about 1-2 KPA from WOT down really.... its something i could work on.

but at the minute i'm building up a ALPHA N tune to try so will see how that goes

[raul arrese]

I tried a few diffrent things but what worked for me the best was 4 lines going into a small chamber and a little restrictor to map .. i uses a mega 2 , solved all my issues ...

[andy198712]

i T'd 4 into 1, but will try a chamber too.

at the min alpha N is running good, but i reckon speed density may net better mpg....

the resolution of ms2 v3 would be a nice upgrade for me also!

[Steve Arndt]

The great thing about SD vs AN is drivability on the bottom. For instance if you ease out the clutch from a stop light the SD mode senses the load because of the vacuum change. With AN load sensing you have to actually give it appreciable throttle to hit higher load sells, actually move the gas pedal to get the fueling needed to match the rpm drop and load from easing the clutch out. With SD the load is sensed by vacuum change. It makes smooth takes off and lugging around much better. My experience.

I use four equal length/volume vacuum lines one to each runner. Those tie in to a 100cc reservoir. From there I run to an inline restrictor drilled 0.040. Then to the map sensor and fuel pressure reg.

I still want to go to a plenum and single throttle though.

[raul arrese]

The great thing about SD vs AN is drivability on the bottom. For instance if you ease out the clutch from a stop light the SD mode senses the load because of the vacuum change. With AN load sensing you have to actually give it appreciable throttle to hit higher load sells, actually move the gas pedal to get the fueling needed to match the rpm drop and load from easing the clutch out. With SD the load is sensed by vacuum change. It makes smooth takes off and lugging around much better. My experience.

I use four equal length/volume vacuum lines one to each runner. Those tie in to a 100cc reservoir. From there I run to an inline restrictor drilled 0.040. Then to the map sensor and fuel pressure reg.

I still want to go to a plenum and single throttle though.

I think you told me to try that set up cause its exactly what i have ... i cant complain about how my engine runs .. idle and transition is great ..

[andy198712]

I too still want single throttle body for turbo lol

But yeah I have found it stalled a little easier, as in I stalled it for the first time lol

Need to make my idle a bit stronger but it does respond well in alpha n..... Will play with it till I sort the vacuum chamber ect and try that again

[emerald]

can some one let me know what the hell ITB mode is .I have tuned lots of make"s of cars and i am yet to see this ITB mode ??? I am one of the Jenvey dealers here and have not come across this before