For anything you'd like to see added to Speeduino
By zomesi
#9316
hi to all my friends
i wanted to ask is there any progress for making ITB mode for speeduino?
and if not is it possible or its hard to add this option? :D
User avatar
By cx500tc
#9317
I've recently started a topic about hardware that could accommodate this. Feel free to drop in and post your questions and suggestions.

ITB / multi-map interface board

Otherwise, Speeduino does not support independent throttle bodies other than pulling readings from a single MAP sensor regardless how it's connected to the system.
By noisymime
#9319
There will at some point be a mixed Alpha-N / Speed-Density mode with blended maps, but it's likely at least 4-6 months away. Until then, either using pure Alpha-N or one of the options with MAP sensor configurations will work, but maybe fiddly to tune.
By zomesi
#9333
noisymime wrote:There will at some point be a mixed Alpha-N / Speed-Density mode with blended maps, but it's likely at least 4-6 months away. Until then, either using pure Alpha-N or one of the options with MAP sensor configurations will work, but maybe fiddly to tune.
you mean this method?
http://77e21.info/images/ITB%20Tuning/ITB_SD.gif
is this in the to do list or not? :mrgreen:
im so crazy about ITBs
:D
i think Alpha-N has problems with close loop idle..as i heard
By alessandromeyer
#14919
Does anyone have a copy of the 77e21.info site? unfortunately the site was taken down and its linked on so many topics concerning ITBs. There must be something worthwhile on it...

@noisymime

What is missing in the code to support ITB-Mode? Is it "just" a simple switching to TPS at higher RPM?

Thanks a lot!
User avatar
By PSIG
#14922
alessandromeyer wrote:Does anyone have a copy of the 77e21.info site? unfortunately the site was taken down and its linked on so many topics concerning ITBs. There must be something worthwhile on it...
You can use web.archive.org to find some of the pages. However, the same info is out there on other sites in different forms if you go searching. One simple description of Alpha-N versus SD is here: SD vs AN
alessandromeyer wrote: Is it "just" a simple switching to TPS at higher RPM?
After reading the differences, you can see there are several ways to combine or blend Alpha-N and SD, including a "blended version, where the MAP is permitted to influence the A-N fueling. Note a switching scheme would usually be from A-N (TPS) at lower rpm, to SD (MAP) at higher speeds. A-N is a relatively "blind" system, and simply gives the engine what it thinks it should have at that particular rpm and TPS—right or wrong—and why it can give smoother (though less accurate) results.

Another interesting note is that, along with the generally over-rich fueling needed to avoid lean spots raising MAP, idle speed control using the ITBs (throttle stop) appears to cause much of the high MAP at idle. When separate idle air bleeds were used with a single IAC, the idle MAP vacuum increased substantially, giving much better tuning control. I can't find the site right now, but simply adding a small plenum behind the ITBs also worked to provide much better MAP and wider range for tuning, much like a standard MPFI car engine. There are ways to handle ITBs without special "load" coding just for them, though it can make tuning simpler for some.

David
By berthfield
#14923
alessandromeyer wrote:Does anyone have a copy of the 77e21.info site? unfortunately the site was taken down and its linked on so many topics concerning ITBs. There must be something worthwhile on it...
I am not sure of the exact page that you need, or if it can be found here, but have a look at the wayback machine. I found an archived page from ~29 June 2016 that might be of interest to you.
Last edited by berthfield on Mon Dec 05, 2016 1:02 am, edited 1 time in total.
By evo_lucian
#14924
I would be very interested in trying out my novice tuning skills on an itb or any Alpha N configuration some day. Are you referring tons vacuum block ? Small canister that connects to all the itb right after the butterflies.
By noisymime
#14927
So I've done a bit of reading, but like PSIG mentioned, there's a few different strategies that all get variously lumped under the term 'ITB mode'. Different ECUs use different methods and to date I don't feel I've known enough of the real world implications to be able to make a call on the 'best' way to implement this. There are also other considerations such as how auto-tune will function with blended tables etc.

If anyone has genuine hands on experience tuning ITBs on other aftermarket ECUs, I'd love to chat about it though! Whilst theory is great, I've read more of it than I care to at this point and would really prefer to hear from people who have used different methods and what they thought of them.
User avatar
By PSIG
#14933
Cool. I can't help much there as I've only played with a couple hobby-level ITB setups. Other than OEM and true racing setups, most of those are for looks with a compromise in performance, so I haven't seen them much. I'd love to do some experiments with some though! Volunteers welcome.
8-)
David
hints & kinks

I have been working on things over a year or so or[…]

I thought that spare ULN pins were configurable fo[…]

Problems loosing sync

Note that some VR conditioner circuits and chips d[…]

connection on board?

me again. I'll probably be on here frequently f[…]

Still can't find what you're looking for?