pcmhacking.net

202t would be a big help is my guess. Also look in the forsale section. You’ll need a Ecm nvram and a comms board

FBUTE wrote:I also have some questions around the whole siamese port thing as well.
I would be keen to read any comments any one has.Cheers

My personal opinion as a long time carb tuner, is that the siamese ported head will be the "spanner in the works" so to speak.
I've not delved too far into the finer points of the delco tuning yet, so not sure if this is an option, but my opinion would be that if the injection timing or
crank angle at which the injector fires could be changed (whatever the right reference / terminology used is), you'd have a chance of getting the tune pretty good.
I'd even think injector postion (distance from the head) would play a part in it's end result.
Again, just my opinion on years of playing and studying what the general themselves did to make things work, the experience of others here will differ from mine.

yeah i think the end result from at least people trying to do the same thing on mini's was that it never works properly unless you go to full sequential injection..... which is not possible with the VN ECM.

Thanks for the replys.Any interest is appreciated.I'll have a look on the for sale section.

Holden202T wrote:yeah i think the end result from at least people trying to do the same thing on mini's was that it never works properly unless you go to full sequential injection..... which is not possible with the VN ECM.

I can't imagine that even that would help much, it's a 6 of one, half a dozen of the other scenario.
The biggest hurdle with all holden 6 heads prior to blue motor is the siamese / shared inlet ports.
The end 4 cylinders pull exhaust gas from the cylinder in it's shared runner.
eg: when cyl 1 is firing, cyl 6 is on overlap, number 5 is drawing fuel in it's cylinder whilst 6's intake & exhaust are both open, some of which ends up in number 5, the reason why most broken pistons end up being number 5 when flogged, being it's the hottest end of the motor.
The late red heads at least had the inlet divider to the manifold bolt on area, though the gasses still shared within the runner entry.
Most likely why the genuine twin carb manifolds had the 2 carbs moved closer to the middle 2 cylinders on the manifold, something that aftermarket manifold manufacturers seemed to overlook.

Something fixed with the blue / black heads and manifold.
I've put these manifolds on late red heads after re-cutting the new stud cutaways in the manifolds and made 4 inches of vacuum at idle from changing nothing but manifold, had more bottom end and ended up needing to retune it from scratch..
The port mismatch is atrocious, yet it still performed better than the std manifold

Ken wrote:

Holden202T wrote:yeah i think the end result from at least people trying to do the same thing on mini's was that it never works properly unless you go to full sequential injection..... which is not possible with the VN ECM.

I can't imagine that even that would help much, it's a 6 of one, half a dozen of the other scenario.
The biggest hurdle with all holden 6 heads prior to blue motor is the siamese / shared inlet ports.
The end 4 cylinders pull exhaust gas from the cylinder in it's shared runner.
eg: when cyl 1 is firing, cyl 6 is on overlap, number 5 is drawing fuel in it's cylinder whilst 6's intake & exhaust are both open, some of which ends up in number 5, the reason why most broken pistons end up being number 5 when flogged, being it's the hottest end of the motor.
The late red heads at least had the inlet divider to the manifold bolt on area, though the gasses still shared within the runner entry.
Most likely why the genuine twin carb manifolds had the 2 carbs moved closer to the middle 2 cylinders on the manifold, something that aftermarket manifold manufacturers seemed to overlook.

Something fixed with the blue / black heads and manifold.

STD_Blue_Mani.JPG

I've put these manifolds on late red heads after re-cutting the new stud cutaways in the manifolds and made 4 inches of vacuum at idle from changing nothing but manifold, had more bottom end and ended up needing to retune it from scratch..
The port mismatch is atrocious, yet it still performed better than the std manifold

What are your thoughts on running the injector closer to the throttle body or before the throttle plate on a multi throttle body application?

Hmmm, I was hoping this wouldn't be too much of an issue.

Tell me if I'm wrong but my understanding is that the Mini engine firing order is a big problem because you have two cylinders which share the same intake port firing immediately after each other? This isn't the case with the grey with the extra cylinders and firing order (1-5-3-6-2-4). They are not always completely separated into different engine revolutions depending on where you slice it but the intake event moves to a different port at least once before back to the same one. Also thinking that double fire injection should help a lot, its not perfect but from what I can see as long as the injectors are not aligned with fuel intake for cylinders 5/2 then there will be a fresh injection event each revolution that is not shared? (If that makes sense)

yeah i think its really going to be a case of trial and error, just keep it in mind if you can never get fuelling to be right its probably because of that issue.

v6bucket wrote:What are your thoughts on running the injector closer to the throttle body or before the throttle plate on a multi throttle body application?

My own belief is that there's too many variables to consider that any one injector location would be of greater benefit over any host of scenarios.
In a perfect world where design faults are minimal, (design faults being head work, cam lobe sep, where cam's dialed in, baseline cranking cyl pressures, mani volume, extractor volume, etc etc,) I would say as close to the head as possible for bottom end / mid range, & another closer to the throttle body starting at mid range / top end.
That's just my opinion though based on my understanding of the functions of camshaft and manifold (mixing chamber) relationships.
Also in part based on partial involvement with other colleges who play around with haltech and the likes on rebuilds they've got me involved in.

Though i'm thinking that the main purpose of this original thread may have gone off course too much for me to dribble too much more though, wondering if maybe it should be parted off into a new thread in another section of the forum, or are the rules not that strict here.

Read my mind, very interested in this topic though