Quote:
|
Originally Posted by GRock
4.89's are perfect for your set up, no need to go with larger. And with the dual runner you will add a higher ceiling to your potential HP, so no worries in that department. Smoother idle and sharper low end and accel with the 4.89's as opposed to the 6.1's. As with a lot of things on strong street bikes, larger is usually not better.
Now for all of you injection junkies, please hear this......
General rule for injector flow rate is to go with lowest flow that will handle your top end and still give you good low speed and idle characteristics. The problem with injectors is that just a small problem with uneven flow or a slight restriction will cost you big time power and raise havoc with tuning. Especially with a lot of bikes that are just driven occcasionally or are seasonal. It doesn't take much for these things to gum up as most fuels now have ethanol in them and this evaporates rather quickly and leaves the heavier compounds behind which can cause problems in engines that are not used every day or are stored. There are many companies that speciallize in blueprinting and flowing injectors and the service is fairly inexpensive. We use a company here in CT for all our racing engines (marine and cycle) that does real inexpensive work on every day injection also. You'd be surprised at the difference you can get from having balanced and equal flow injectors on a bike that had tuning troubles.
A certain cycle company was having troubles with the "stock" injectors and they were blaming poor perfromance on the spray pattern of the injectors. Bullshit!! The injectors were not flowing equally in many cases and were not matched. So the mantra was to trade them out for a different spray pattern. It wasn't the pattern it was a combo between balanced fuel delivery and a higher flow rate that that matched up better with the fuel mapping and the result was better idle, smoother performance and cooler running.
OK, now my hands are tired!!!
All the best.
G
|
So if a guy was to send off a new set of injectors to these folks what kind of cost would be associated with it?
I also listened on your injector/TB lesson when I asked a while back. It is why I went to the BC. More horse power supported with stock injectors, and clean air charges into your cylinders, no air robbing with the fast (ski slope) cams. I think the best move if you are going in for a new TB, but I am a little biased.
Have to say I never thought of injector tunning, or flowing each but if it is not too cost prohibitive I would like to check it out. Since we are talking about only having two yes I see how it could be a issue in tunning.
Oh and while you are here have this low idle thing going on, does not matter punching it or just moving along, come to a stop idle drops, if I can stay stopped long enough it will pick up and then all is well, if not a restart does it.
Also on the bike warm option screen would you not want that at the temp you set IAC at? Default is 95C IAC set at 110C with live view.
And do you have any experience with the auto IAC update?
I been unchecked it and using 30 as nominal IAC in the set up screen.
auto barometric pressure update?
Both of these I wonder how they affect performance of the bike if they are always sampling, seems like something else is gonna suffer.
Still not reliable in the 0-2.5% BLM corrections, correct?
Anything specific on the BC T/B I should use/try/watch out for?
Thanks for the help as always............
