tte turbo boost

[Anonymous]

If this holds true though, wouldn't that suggest that there's absolutely no benefit fom having the duct fitted anyway?

Just to play devil's advocate.

possibly not with the TTE set up. but on the pother hand, we are saying that opening up the air flow wont adversly affect anything as 'more air the better'

in regards to the TTE set up then possibly there may not be any added value due to the wastegate being at such a low boost, but in NA form it should be advantagious.  But likewise I cant see how having that extra flow would cause the car to run lean  (TTE set up)

[Anonymous]

now im more confused than ever   s:? :? s:?  

does it work or doesnt it ?

although i believe what SP are saying and carnt see a reason for them lying, maybe a more detailed answer on this issue is required! or is it the fact that SP are playing it safe with how the car operates with a induction kit?!

[loadswine]

SP would have to play it straight down the line with the TTE kit,as its Toyota  sanctioned and carries their warranty, I would have thought.
I wonder how much extra air or boost has to be run for the standard injectors to max out. If the gas flow is altered with a non standard exhaust, would that throw a spanner in the works in a similar way?

[markiii]

too take the last points from Bossman and Nigel.

I don't think anyone is accusing SP of lying, far from it.

However as pretty knowledgeable enthusiasts we often debate points of contention until we fully understand teh point, I think we are all very interested in further clarification of anything that expands our knowledge. We simply need a litlle mre convincing than your average bunch  s:wink: :wink: s:wink:  

Ref "The Official Line"

I agree, there is what TTE would say, however the SP240 is a huge change so SP are obviously not shy about "improving things" it's liek any mod not factory sanctioned if you choose to do it you may invalidate yoru warranty, however practice is anotehr matter entirely.

[spit]

I wonder how much extra air or boost has to be run for the standard injectors to max out.

I suppose the high end of the "permissible boost range" that the spec. sheet refers to gives some indication? .... but we don't know just how hard the injectors are being worked at that level or arguably if its the injectors/duty cycle that have determined this ceiling figure.

I think we'd expect TTE to have left a bit of latitude above the spec'd. figure for safety too.

[TommyD]

Surely all anyone is doing by changing the standard plastic piping to the markii metal pipe is allowing the air to flow slightly better through the original system. It uses the original MAF positioning afterall.

The TTE uses the original air system and original MAF position, so using a Markii pipe or the original TRD one with a better filter should only improve the TTET performance (within the tolerance range we know exists in this plug and play system - ie every car will be slightly different, some better than others - some with better air flow - some with better exhausts, different waste gates etc) we are seeing some TTET hitting 200HP.

Now SP's induction system used a new shaped system with a new MAF position to an after market air filter which threw cels (ie beyond the tolerance levels the plug n play ecu could handle), 2 completely different systems really.

Shoot me down in flames if this is totally wrong

[firepower]

( However as pretty knowledgeable enthusiasts we often debate points of contention until we fully understand the point,)  

as markiii said
that is exactly it this is a discussion forum and all we are trying to do is to understand all the relevent points raised by throwing other issues in to the discussion and questioning them and hopefully getting the answers  s:) s:)

[Anonymous]

although i believe what SP are saying and carnt see a reason for them lying

sorry guys! probably the wrong choce of word used there   s:oops: :oops: s:oops:

[Leeber]

Ok, my knowledge in this area is a little flaky, so I'm perfectly happy to admit that my logic may be totally flawed. However, I thought that all the wastegate does is modulate between open and closed to maintain the predetermined boost pressure in the inlet manifold/duct. If the pressure is above 7 psi, the wastegate opens to allow more exhaust gas to bypass the the turbine which slows down, thereby reducing the compressor speed and hence the pressure in the inlet duct. If the pressure is too low then the wastegate closes, diverting more gas through the turbine which then speeds up. If this is true, surely the nature of the intake, upstream of the point at which the boost pressure is monitored (the MAF I presume) is totally irrelevant (within reason). It should, in theory, be compensated for by the position of the wastegate, as long as it's not in the fully open or fully closed state. If the air is allowed to flow more freely by the use of a less restrictive intake, then the wastegate will be allowing slightly more of the exhaust gases to bypass the turbine, which will not be working quite so hard. The net result would be no performance gain at all, in fact I guess that taken to the extreme, it could increase turbo lag slightly.
Sorry if this sounds like an egg-sucking lesson, it's really not meant to be, I'm no engineer (as I'm reminded on a daily basis by individuals far more intelligent than me).
All meant in the spirit of healthy debate of course.   s:D s:D

[firepower]

If the pressure is above 7 psi, the wastegate opens to allow more exhaust gas to bypass the the turbine which slows down, thereby reducing the compressor speed and hence the pressure in the inlet duct. If the pressure is too low then the wastegate closes,

that would be my understanding of it as well so if my turbo is running at 5psi does that me that the spring in the wastegate is weak or that it is just set up wrong  s:? :? s:?

[Leeber]

I'm guessing the latter, but that's only assuming that my understanding of the system is correct which is by no means a given. I'm hoping that someone with more knowledge than me is kind enough to set me straight.

[spit]

I'm guessing too .... but if the actuator on the turbo is pressure-checked before despatch from the factory and its working well (most probable IMO), then its possible that your actuator arm length is allowing for a bit of leak at the wastegate, and this is preventing a full snort to 7psi+.

What only came to light late on in the proceedings was that the actuator arm length is adjustable on the TTET .... its just not something that features as a required mod during the install procedure.

So, I reckon with the appropriate monitoring you can get this problem resolved if you so wish Phil - and still be within the tolerances set by TTET to keep your warranty nicely intact.

[markiii]

I'm guessing too .... but if the actuator on the turbo is pressure-checked before despatch from the factory and its working well (most probable IMO), then its possible that your actuator arm length is allowing for a bit of leak at the wastegate, and this is preventing a full snort to 7psi+.

What only came to light late on in the proceedings was that the actuator arm length is adjustable on the TTET .... its just not something that features as a required mod during the install procedure.

So, I reckon with the appropriate monitoring you can get this problem resolved if you so wish Phil - and still be within the tolerances set by TTET to keep your warranty nicely intact.

hmm me thinks I should dig out my contacts at TTE and see what they think about teh actuator arm discussion

[Silverstone Performance]

We're all guessing to an extent.  The TTE electronics are completely unknown in terms of what their parameters and limits are.  Based on our findings, we suspect that the electronics have a limited amount of fuel, for given conditions, that will be allowed (either limited by programming or limited by the physical limits of the fuelling hardware - we encountered the latter early in the development of the 240 upgrade).  Therefore, we suspect that if you put more air in, the electronics are not necessarily capable of adding sufficient fuel to get a good AFR.

We don't know for sure and the official line from TTE is that as long as your car is standard (i.e. the basis of the TTET) then there are no problems.  Furthermore, we are satisfied that the SP exhaust system does not adversely affect the TTET hence its introduction.  Conversely we were not satisfied that the induction kit so we have not introduced it.  If someone else is offering an upgrade for a TTET car then it is their responsibility to prove that it is suitable or to accept the consequences if it is not - this is the commercial reality of the system (although I think it's fair to say that Markiii's pipe is not strictly a commercial product so he should be exempt   s:D s:D  ).

Regarding "actuator rod adjustment", we don't really want TTE to get involved in this debate cause this is a sure fire way of invalidating someone's warranty!

Enjoying the debate...   s:lol: :lol: s:lol:

[markiii]

Matt,

thanks for that but you still haven't clarified why you feel the markii pipe can cause things to run lean?

as a number of us seem to be struggling with teh physics of how a turbo with a boost limit can flow more air with or without one I'd love to hear your thoughts?

as a reminder guys, I have always stated that no evidence of performance exists in "any" circumstances

[Silverstone Performance]

Enjoying the debate...   s:lol: :lol: s:lol:

So much so that I've duplicated my post...  s:? :? s:?

[Anonymous]

There must be something in it Mark or TRD would not have brought out there expensive replacement.   s:wink: :wink: s:wink:  

Rob.

[Silverstone Performance]

thanks for that but you still haven't clarified why you feel the markii pipe can cause things to run lean?

Based on our findings...we suspect that if you put more air in, the electronics are not necessarily capable of adding sufficient fuel to get a good AFR.

If you put more air in and the electronics/ hardware can't keep up then it will run lean.  It's only a suspicion though!

[Silverstone Performance]

There must be something in it Mark or TRD would not have brought out there expensive replacement.   s:wink: :wink: s:wink:  

Rob.

For a normally aspirated car that has injectors working at a capacity well below that of a turbo'd car.

Has anyone done a back-to-back before and after (all other things remaining equal) dyno for the Markiii pipe?  This would help understand the NA condition.

[Anonymous]

Matt

Are you talking purely turbo'd cars or are you saying this applies to N/A as well?

you beat me to it mate  s:oops: :oops: s:oops:    s:wink: :wink: s:wink:

[northernalex]

you would think the electronics would have a fair amount of "give" though.  Driving at different speeds and at different air temperatures will give rise to more/less air flow (obviously)

With a markiii pipe you're surely just tricking the system into thinking you're travelling at 70mph when you're doing 65 for example.  Surely running lean wont happen till you reach the electronic limits, which i guess will be set towards 100mph+..??

[markiii]

thanks for that but you still haven't clarified why you feel the markii pipe can cause things to run lean?

Based on our findings...we suspect that if you put more air in, the electronics are not necessarily capable of adding sufficient fuel to get a good AFR.

If you put more air in and the electronics/ hardware can't keep up then it will run lean.  It's only a suspicion though!

now see I agree with your statement generally

however how can a turboed car flow more air under boost than teh wastegate spring is set for?

If you placed a big enough restriction on teh inlet I can see psi being reduced (it would have to be big mind you)

but you could run with no air filter and it still shouldn't be able to make more psi than the wastegate is set for,

or are we missing something?

[Silverstone Performance]

Driving at different speeds and at different air temperatures will give rise to more/less air flow...With a markiii pipe you're surely just tricking the system into thinking you're travelling at 70mph when you're doing 65 for example.  Surely running lean wont happen till you reach the electronic limits, which i guess will be set towards 100mph+..??

The ram air effect is negligible, the main influence of air induction is the throttle position and RPM, hence you might run into this condition only when you're at full load (e.g. when you're on a dyno).

[northernalex]

Driving at different speeds and at different air temperatures will give rise to more/less air flow...With a markiii pipe you're surely just tricking the system into thinking you're travelling at 70mph when you're doing 65 for example.  Surely running lean wont happen till you reach the electronic limits, which i guess will be set towards 100mph+..??

The ram air effect is negligible, the main influence of air induction is the throttle position and RPM, hence you might run into this condition only when you're at full load (e.g. when you're on a dyno).

So you're saying the air flow into the engine is constant (to the first approximation) no matter what the air temperature/car speed?

[Silverstone Performance]

however how can a turboed car flow more air under boost than the wastegate spring is set for?

My thinking is this:  If you operate a vacuum cleaner (the motor creating a vacuum to a given level determined by the limit of the motor - this is the same effect as the induction vacuum created by the turbo).  Which size of nozzle you put on the end will determine the amount of air that actually flows... if you block it ,the vacuum (i.e. pressure, albeit negative) will not change, but the air flow will.  Same principle in reverse.

So you're saying the air flow into the engine is constant (to the first approximation) no matter what the air temperature/car speed?

I'm saying that at full throttle (the point at which AFR becomes critical, we think) the air flow can be significantly increased (beyond what the electronics might be able to accomodate) by a change to the induction pipe.