Originally posted by regcheeseman
View Post
Announcement
Collapse
No announcement yet.
My second T4, operation de-chav
Collapse
X
-
To map your data against a manufacturers compressor map you need to calculate the pumping volume of the specific engine.
CFM=L x RPM x VE x PR / 5660
CFM = cubic feet / minute
L = Engine Displacement in litres
RPM = revs per minute
VE = Volumetric Efficiency (use 0.8 for 2 valves per cylinder)
PR = Pressure Ratio
This is the air volume pumped by the engine which is then mixed with fuel for the desired AFR.
Garret use lb/min for their maps (CFM÷14.27)
3K use m3/sec for their maps (lb/min ÷ 162.04)
So, using different rpm rates you can plot the air mass that's being produced at different boost pressures. Keeping the pressures within the turbos tolerances and within the efficiency clouds ensures the air being pumped is done so efficiently.
Comment
-
Thank you.
Having a think about my limp mode symptoms last night.
Tried to log it on Friday - wouldn't do it!
Anyway, it's a pressure deviation fault code, I'm a assuming the actual boost is less than the ECU expects to see?
If I'm coasting at 60mph, momentum is driving the engine and there is 0 load.
Now if I want adjust my road speed, I bring in the throttle gradually to say 10%, not enough to create any drive, enough to reduce the engine braking effect and reduce deceleration.....still 0 load
Limp mode is triggered
I take it the ECU does not care about road speed or selected gear?
Does the ECU see the revs (2100 - 2200), see the 10-15% drivers wish input, and eventually comes up with a boost figure required?
But because the engine has no load there;s no boost created and the ECU throws a wobbly?
But then.....ECU doesn't know load either, so boost should relate to IQ????
Dunno???? What I do know, is that the limp trigger only happens in a very small window of parameters and when you try to provoke it you can't.
Comment
-
Originally posted by regcheeseman View PostThank you.
Having a think about my limp mode symptoms last night.
Tried to log it on Friday - wouldn't do it!
Anyway, it's a pressure deviation fault code, I'm a assuming the actual boost is less than the ECU expects to see?
If I'm coasting at 60mph, momentum is driving the engine and there is 0 load.
Now if I want adjust my road speed, I bring in the throttle gradually to say 10%, not enough to create any drive, enough to reduce the engine braking effect and reduce deceleration.....still 0 load
Limp mode is triggered
I take it the ECU does not care about road speed or selected gear?
Does the ECU see the revs (2100 - 2200), see the 10-15% drivers wish input, and eventually comes up with a boost figure required?
But because the engine has no load there;s no boost created and the ECU throws a wobbly?
But then.....ECU doesn't know load either, so boost should relate to IQ????
Dunno???? What I do know, is that the limp trigger only happens in a very small window of parameters and when you try to provoke it you can't.
No gear or road speed inputs on this ECU.
Just a thought but have you got another 2.5bar MAP sensor? The tolerances with two identical sensors can be quite broad.
I'm back at home for a few days R&R.
I'll take a look at the -20% map if I can get away from the list of chores. I'm sure it's just a tweak that's needed around the 2000 - 2500 rpm , could be just a single plotting point.Last edited by Activ8; 16 September 2019, 02:13 PM.
Comment
-
Makeover time, bored of the old interior, my needs have changed somewhat so I've started to rip it all out.
The problem with building the van furniture in situ is that most of the screws that fix the first battens in place that everything build onto are often obscured by later additions or designed to be hidden or just buried under the final trim.
Final got the cupboard out, it wasn't giving up without a fight though, chunks of the floor came up with it
Comment
-
Not sure how I'm going to lighten the interior, previously it was a bit dark, a sea of dark grey veltrim four way stretch carpet
might bring some more wood in the design, ideally the roof lining needs to go, I'd love something like sausage has for his roof - he owes me a few hours....
It's not started well though, the plan to lighten it, what am I replacing the black leather upholstered rock and roll with? Yep even larger black leather seats,
A bit like these
wish I'd hunted down some cream versions or maybe some two tone ones, they were an impulse buy, cheap and fairly local.
Comment
-
Originally posted by regcheeseman View PostNot sure how I'm going to lighten the interior, previously it was a bit dark, a sea of dark grey veltrim four way stretch carpet
might bring some more wood in the design, ideally the roof lining needs to go, I'd love something like sausage has for his roof - he owes me a few hours....
It's not started well though, the plan to lighten it, what am I replacing the black leather upholstered rock and roll with? Yep even larger black leather seats,
A bit like these
[ATTACH=CONFIG]13740[/ATTACH]
wish I'd hunted down some cream versions or maybe some two tone ones, they were an impulse buy, cheap and fairly local.
https://rover.ebay.com/rover/0/0/0?m...2F202782418281
Comment
-
-
Originally posted by Activ8 View PostI'm intrigued , so how do they fold?
Just nicely designed and very neat.
Also the bases lift, so when I fit a base to lift them up it'll make a hidden storage area with the seat being the lid.
Plan is to put everything on rails, the seats will go in with a low height, removable storage box behind.
When I go camping, the seats and the storage box will come forward giving enough room for a separate camping pod to slot in by the back door. The camping pod should have a two ring cooker with grill, the gas bottle and maybe a couple of drawers with kitchen/camping tat in them.
At least that's the plan..... for now the van is empty
very noticeably lighter, the rear end has popped up about 20mm and I have some rake going on.
That's my new car in the background - a 3 cylinder corsa given to me by the neighbours, not sure what to do with that yet, but my boy is 16 soon and driving lessons wont be far away. He has absolutely no interest in cars so a corsa should suit him.
My youngest Josh (who a few met at Action) loves cars and seems to think he'll have a R32 skyline as his first car, he'll be decimated when he realises insurance will limit him to a very similar box of misery like his elder brother endured.
Comment
Comment