things like tailoring the accel enrichment curves (ems only allows you to inject a %age) to suit the response of the ITB's as well as using a second table to multiply the main fuel table based on MAP - ie to remove fuel from the main Alpha-N table when there is vacuum, to give better A/F ratios under light / cruising etc. (you cant tune ITB's based soley on MAP as you can with a plenum.)

The newer extra firmware has 'ITB' mode which is a mix of MAP and Alpha-N specifically for ITB's, but i have found it better using the two tables as described above as it gives greater control.

Also MAP sampling, which will give you a more stable MAP reading with ITB's, where you can sample the map signal from x degrees crankshaft rotation, for a y degree window.

Do you know if they have released the MS-II Sequencer yet, so it can do sequential? I had a quick look but can only find "to be released late 2009".

I do like the idea of this feature, a few articles have said MAP can be a bit confusing for some ECU's at idle with ITB's and a bigger cam. Is there an Australian distributor for the kits and accessories? or is it all mail order from OS.

MS-III is currently under developement, which will support sequential etc, however sequential is only good for low rpm anyway, as at high rpm they all switch back to batch fire anyway.

MS-II's you can order directly, or alternatively I get qty's of them in every 8-10 weeks, with harnesses.

Not sure what ticky uses but I had this written down, I think I got it somewhere from the net so unfortunately it is in imperial measurements.

L = ((EVCD x 0.25 x V x 2) / (rpm x RV)) - 0.5D

EVCD is Effective Valve Closed Duration
RV is Reflective Value (ie what order you are tuning to; 1,2,3,4,5...I wouldn't go past 4 though)
V is Pressure wave speed (approx 1300ft/s at temperature)
D is Runner Diameter (in inches)

To calculate EVCD you take the duration of your cam away from a whole cycle rotation of the engine (720 degrees). On top of this you want the pressure waves to arrive before the valve closes and after it opens, so you need to subtract some duration from your cam. I have it written advising of subtracting 20 degrees from smaller cams or 30 degrees from bigger cams (ie, if you have a cam with 300 degrees duration your EVCD would be 720 - (300-30) = 450.

Here's an example I did in excel for a cam with 300 degrees duration and a runner diameter of 1.5in. Reflective value on vertical axis and rpm on horizontal, with runner length in inches in the middle.

Last edited by skidder on Mon Feb 15, 2010 10:23 pm, edited 1 time in total.

the 6860 can use two load sensors any combination (or multiples of) on MAP, TPS, AFM. on top of that it also has barometric compensation. which will greatly help any one tuning using Alhpa-N
and closed loop lambda with two sensors, when using wide band sensors lets you choose target AFRs.
Not to mention the duel maps again (both ignition and fuel), that are changeable on the fly using any one of the spare inputs. wouldn't be hard to set up the second maps to suit cruise/economy (as we all know the igntion plays just as big a role in economy as fuel does.)
set it using wide band and target AFR tuned for lean cruise and the second ignition map to suit.


I really don't want to start an other MS vs the word thing. i just think MS people can be a little to passionate about them some times. And tend to gloss over and play down commercial offerings. when at the end of the day if set up right you i doubt the driver would notice the difference.

i agree with you about the starting a vs war - it wont achieve anything, and its not my intent.

With ITB's you cannot tune for lean cruise using TPS based tuning, nor can you tune for power using map based tuning as you can reach max load (ie 100kpa) at as little as 10% throttle. Then you need to account for the extra fuel required for the other 90% throttle.
This is due to the lack of vacuum and hugely different air requirements of the engine at different throttle positions and RPM.

Using alpha-n you need to tune for mid 12 afr's at all rpm and all throttle positions, because there is no way to determine engine load. you could be under power at 3% throttle or you could be cruising at 3% throttle, the ecu will still inject the same amount of fuel.
This is where your closed loop targets will also fail, unless you can set your target afr table to use map readings for load, when your primary algorithm is alpha-n. Most ecu's use same load sensor for all maps.

The problem with this is that you will cruise at rich a/f ratios unless you can set up a multiplier table to pull fuel based on vacuum.
For example, one of my setups pulls upto 30% fuel from the primary alpha-n table based on vacuum, from 30-70kpa - this results in cruise afr's in the 14's and acceleration afr's in the mid 12's and decel in the 15's. Unfortunately you wont get this fexibility in some of the mainstream ecu's.

Closed loop will help with the cruise stuff, but then you need to have your closed loop corrections take out a lot of fuel.

With the MSII's you can do all this without needing to switch maps etc(although you can switch between 2x fuel maps, as well as the 3rd multiplier map still operating) Your primary fuel map can be alpha-n, multiplier map based on MAP and spark tables based on MAP.

It hugely depends on what the intended purpose of the vehicle is, ie track only or daily driver, i've used both ecu's but found one to be a lot better in running itb's than the other.

Some good info and food for thought in the above posts, cheers guys.

You will need a balance tube to link all 6 TB's, and hook your brake booster and if using a MAP sensor, to this.

This is what i currently have in the car atm.
I have just sold my old set of Individual throttle bodies .
Best of luck

...

Last edited by Brockyb8 on Tue Feb 16, 2010 11:07 pm, edited 1 time in total.

Brockyb8

How much more power did you get with this setup which is awesome

That's a nice looking manifold brockyb8.

dsyfer, what's the duration of your cam?

To be honest you dont really get heaps of power for doing this.
For the amount of money to the bits u put in tis setup there are better things u can do
That setup there with cam head and computer got me 178.6.
The previous owner had 170 - OPLEASE

Hey Brockyb8, this picture is not showing up? the old two are though, I'd like to see what the new setup looks like.