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Re: Megasquirt - a story of injection

Posted: Sat Sep 16, 2017 4:54 am
by hybrid
Normally you would wire them up the same as wasted spark, so you'd follow the firing order.
Even adjusting per bank, you still don't know what's causing the difference.
If one injector is faulty and injecting too much fuel, you'll end up leaning off all the others.

I'm not sure if MS2 can do separate fuel tables for each output, or whether you just trim fuel out of an output. I've never looked into how that works because IMO the benefit is minimal.

Re: Megasquirt - a story of injection

Posted: Sat Sep 16, 2017 9:43 am
by Husky65
I've actually been looking at the haltech elite ecus(please don't stone me). They can do long term learning on both banks separately using dual widebands, which is why I was just wondering if you wiring up the injectors together one one bank would allow easier fuel trimming.

Re: Megasquirt - a story of injection

Posted: Sat Sep 16, 2017 9:46 am
by Husky65
Dwayne wrote:My edelbrock pro-flo uses 4 injector channels to fire with the 351 firing order: 8/4 2/7 1/3 5/6
Dual or single o2's?

Re: Megasquirt - a story of injection

Posted: Sat Sep 16, 2017 7:06 pm
by hybrid
You must be feeling rich.
The same principles apply with any ECU.
If you're looking at an O2 per bank, a bad cylinder will drag all the other cylinders in the wrong direction.

Re: Megasquirt - a story of injection

Posted: Sat Sep 16, 2017 7:16 pm
by Dwayne
Single narrow band o2 sensor, but internet's says it's easy for me to fit wide band guage instead.

The wiring diagrams for old and new firing orders are both around pg 32 of the downloadable instructions. Part #3521 is old firing order, and #3541 is the new firing order so injector wiring slightly different between them but the rest is the same.

Re: Megasquirt - a story of injection

Posted: Sat Sep 16, 2017 7:34 pm
by boofhead
duel o2 allows ego1 and ego2 but wiring for each bank

Re: Megasquirt - a story of injection

Posted: Sat Sep 16, 2017 7:39 pm
by Husky65
hybrid wrote:You must be feeling rich.
The same principles apply with any ECU.
If you're looking at an O2 per bank, a bad cylinder will drag all the other cylinders in the wrong direction.
Yup, understand that, but the same applies to a single wideband also i guess. I mean, you'll never know of a rich/lean cylinder unless you get a wideband on each runner. So in terms of just a tuning tool, i guess I'm asking if there is any benefit by going to dual widebands and independant bank adjustment?

Re: Megasquirt - a story of injection

Posted: Sat Sep 16, 2017 7:41 pm
by Husky65
boofhead wrote:duel o2 allows ego1 and ego2 but wiring for each bank
The haltech is a nice system where you wire in the controller, then both widebands feed to the controller, and the signal is then sent from the controller to the ecu via one CAN cable. Good for problem solving with the o2's also as the CAN will let you know what's going on.

Re: Megasquirt - a story of injection

Posted: Sat Sep 16, 2017 7:51 pm
by boofhead
I see no advantage but MS can do it that way if required IO extender

Re: Megasquirt - a story of injection

Posted: Sat Sep 16, 2017 11:01 pm
by hybrid
Yeah the IO extender I put in mine has a dedicated O2 input where you can chain up to 16 O2 sensors together.

Re: Megasquirt - a story of injection

Posted: Sat Sep 16, 2017 11:53 pm
by Husky65
Why do modern v8's run dual o2's then? Do they just average the reading between the two and use this to adjust off? Or do they adjust seperate banks?

Re: Megasquirt - a story of injection

Posted: Sun Sep 17, 2017 12:38 am
by boofhead
some do either - all depends. MS can do it all.

Re: Megasquirt - a story of injection

Posted: Sun Sep 17, 2017 12:48 am
by Shaunp
Husky65 wrote:Why do modern v8's run dual o2's then? Do they just average the reading between the two and use this to adjust off? Or do they adjust seperate banks?
I thinks its because they are running them on the edge in an effort to make power and meet emissions and the are altering the fueling in a more dynamic manner then we need to, they all run knock sensors as well etc. In our engines the only benefit I see is know which bank is not running correctly.

Re: Megasquirt - a story of injection

Posted: Sun Sep 17, 2017 1:39 am
by Husky65
Yeah, so more useful as a diagnostic tool I guess instead of an afr adjustment tool. I would like to add a knock sensor also.

Re: Megasquirt - a story of injection

Posted: Sun Sep 17, 2017 1:51 am
by Shaunp
Husky65 wrote:Yeah, so more useful as a diagnostic tool I guess instead of an afr adjustment tool. I would like to add a knock sensor also.
I think with a blower it may be a good idea, perhaps, as long as they dont false trigger, I dont have one in mine. I think its part of the expansion board which also gives sequential injection.