|
Waggin |
|
|||
|
sickd wrote: the bbm works on vacuum as long as there is vaccum the butterflies will open they just wont be able to be controlled to a fine degree by the eecv but i dont think it make that much difference
wat exactly does the ecu control on the bbm Exactly as stockstandard says.. the ECU swiches a vacuum solenoid which actuates the BBM butterflies using vacuum.
_________________ WAG363: AUII LTD Supercharged 363 Dart Stroker [Supercharged 363 LTD Build] |
|||
Top | |
Andrew J |
|
|||
|
Theres been quite a bit of thought about when it is optimum for the runners to open on the i6's. We know they were designed to open at a certain rpm but this is for a stock motor! Has anyone played with the setting to remove he little bit of a flat spot? Ive seen on some dnos that theres been a fair bit of a jump at some stages. Would be interesting to get a dyno map of all short runners, from idle to say 5k, and one with the long runners, then overlap the two graphs, and decide where to switch it. Or am i just saying the blatantly obvious that everyone has been doing for the last few years.... Anyone had a play with it?
_________________ The problem with America is stupidity. I'm not saying there should be a capital punishment for stupidity, but why don't we just take the safety labels off of everything and let the problem solve itself?
|
|||
Top | |
stockstandard |
|
|||
|
Problem is that the ECU expects that the runnes will swtich at 3600-3800 rpm and changes its tune at that point. If you move the swiching rpm say with a frequency switch, the tune will still be out. You would really need aftermarket engine management and a lot of tuning time to find the optimal place. Even then your only talking about a few kw gain over a couple of hundred rpm at most.
_________________ Stoke me a clipper, I'll be back for Christmas |
|||
Top | |
Dellboy999 |
|
|||
|
OK guys, I knoe exactlwy how the runenrs work, and what they do, here is the BIG problem with the BBM at 4,000rpm it has no legs, no guts and does nothing, so either lower the switch point from 3,8000rpm or do nothing, you cannot raise it, as the manifold has nothing to give, I belive the 'flat spot' is due to a lag in the switch, if it could be a snap open and close of the switch might fix the problem.
Andrew J in a few weeks or so, I will carry out the test you want to see the results on MY motor at least, to try settle some arguements perhaps. I am in contact with XR9Ute via email, so sooner or later I will be having some fun tuning.
_________________ Full working BA Shifter now upgraded to BF Shifter. |
|||
Top | |
sickd |
|
|||
|
awsome sounds good
i read somewhere on here a while ago the turbo ba does not have the butterflies inside whats that about
_________________ BA XR8 BOSS 260
|
|||
Top | |
stockstandard |
|
|||
|
Forced induction intakes work very differently to NA. Simply, for turbo engines BBM has no advantage.
oh, and this might interest some. Ill let you work out which line is long and short. The torque lines are the interesting ones...
_________________ Stoke me a clipper, I'll be back for Christmas |
|||
Top | |
Dellboy999 |
|
|||
|
Red = Short
Blue = Long I cant tell exactely what I am seeing here though ?
_________________ Full working BA Shifter now upgraded to BF Shifter. |
|||
Top | |
Waggin |
|
|||
|
Dellboy999 wrote: Red = Short
Blue = Long I cant tell exactely what I am seeing here though ? Red is Power, Blue is Torque. The higher power reading is with short runners. The torque curve which dies off at 4000rpm is the long runners. You should also plot a run with the BBM switching to see what happens when its switched at 3800rpm. In theory it should take the best points of each curve
_________________ WAG363: AUII LTD Supercharged 363 Dart Stroker [Supercharged 363 LTD Build] |
|||
Top | |
Dellboy999 |
|
|||
|
ah i see, both lines cross at 4,000 rpm, fancy that
_________________ Full working BA Shifter now upgraded to BF Shifter. |
|||
Top | |
4.9 EF Futura |
|
|||
|
Dellboy999 wrote: Red = Short
Blue = Long I cant tell exactely what I am seeing here though ? The two blue lines would represent torque i assume. My guess is that the torque curve which peaks first is the long runner. The torque curve which peaks second is the short runner (and corresponds to the higher peak HP). The 'dip' in the power curve when the runners switch could be seen as a bad thing... but look at the two curves - at all times, except where the two lines meet, you are better off!
_________________ I promise..... I will never die. |
|||
Top | |
Dellboy999 |
|
|||
|
4.9 EF Futura wrote: Dellboy999 wrote: Red = Short Blue = Long I cant tell exactely what I am seeing here though ? The two blue lines would represent torque i assume. My guess is that the torque curve which peaks first is the long runner. The torque curve which peaks second is the short runner (and corresponds to the higher peak HP). The 'dip' in the power curve when the runners switch could be seen as a bad thing... but look at the two curves - at all times, except where the two lines meet, you are better off! Actually looking at it, it doesnt appear to be runner switching being too slow causing a dip as such, but the runners themselves by default when you look at the grpahs.
_________________ Full working BA Shifter now upgraded to BF Shifter. |
|||
Top | |
stockstandard |
|
|||
|
I think that dips or flatspots in the power curve at the runner switch may have something to do with turbulance in the manifold as the air changes path.
_________________ Stoke me a clipper, I'll be back for Christmas |
|||
Top | |
Dellboy999 |
|
|||
|
We are heading a little off topic, but this is all good info.
Is the BA BBM pretty much the same, or had a MAJOR overhaul seeing as they make more power.
_________________ Full working BA Shifter now upgraded to BF Shifter. |
|||
Top | |
Andrew J |
|
|||
|
I was initially thinking of the fact that it was a single tune, and not two. Sort of like if you put an el manifold into an ea, and kept the standard computer and injector setup. But yeah, any research would be good As far as i know, the switch is controlled by electric over air, so that the vacuum opens it, but the electronics determine when. Vacuum can be slow to open i, so would changing the actuator be viable? It could be some sort of coil arrangement, as its not normal for a motor to be wide open for long, unless doing a burnout or something.
_________________ The problem with America is stupidity. I'm not saying there should be a capital punishment for stupidity, but why don't we just take the safety labels off of everything and let the problem solve itself?
|
|||
Top | |
Dellboy999 |
|
|||
|
The actuator actually drops vaccuum.
actuator is closed for long runners, and open for short (no vaccuum). takes a bit to get used to the concept.
_________________ Full working BA Shifter now upgraded to BF Shifter. |
|||
Top | |
Who is online |
---|
Users browsing this forum: No registered users and 51 guests |