TB993tt

Haven't got time to reply at the mo but WTF are these two gems of BS about ?

TB993tt

So Nick, why do you bother ? why don't you just have me on ignore ?

I'm not sure you even read anything properly ?

I said that the 996GT2 racer uses VTG turbos and Bosch MS 4 ECU so it has no provision for vane actuation - quite how you misinterpret that into "your tuner can't control vanes properly" ?

Why are you talking about GT2 intake manifolds in 5 ? GT2 intake manifolds are good for 680PS on RS dyno, he is trying to use GT3 manifolds, that is the pic above - WTF is that to do with your "intake tract stress" on GT2s.

You still probably think the GT2RS has different turbos to the GT2 cos you said that is what your tuner told you ?

Your attempts to mock RS are embarrassing, they build 100 Porsche race engines every year, these are not track day cars they are real racers. Consider your big valve heads, have the valves been tested in a race Porsche turbo engine ? I'm sure they will last fine for your DE/track day activities but would they last in an endurance race in an 840PS Porsche turbo, one whose 840PS is actually still there during the race ?

Just one last one cos I can't resist
You are talking about VTG turbos, if you read what I said RS build the engine which powered the Alzen record breaking 400kph turbo Porsche, it is a 3.9 very similar to mine and it uses VTGs with the vanes fixed to produce 1050PS - how does it not occur to you to consider these facts (ie it is a verified record and this engine exists and did it) and maybe consider easing up on trying to spout your text book stuff on turbos.

Show us something tangible in terms of performance data or racing/record success or really I'm sure most reasonable people would have to say you are making a fool of yourself

pete95zhn

Few notes, questions and wondering...

VTG turbos and controlling them.
I don't completely understand this "vanes locked open" issue. It either must be a flaw in translation or a case of lack of knowledge from engine tuner. VTG actuators are electronically controlled by the ME7.8.1. Their maps are in % of opening related to rpm and boost pressure. Highest and lowest opening %s are reserved for calibration and self-testing, ie.when the engine is running vanes are never either fully closed or fully open.
So I can't avoid thinking that "vanes locked open" comes either from the fact that the tuner has expanded the opening scale to the highest %s in order to increase exhaust flow with high hp and thus keeping the engine from overboosting and exploding. His skills in english have just not been good enough to explain that... Or the tuner has ditched the ME7.8.1 and really done a quick and dirty vane control solution by mechanically locking the vanes to fully open position. Which IMO is something really strange for a couple of reasons. Firstly the engine would be really laggy, getting it boosting would require minutes, not seconds and secondly even I can build a system where an auxiliary unit controls VTG's actuators. Actually I have done that it...works quite nicely. 996's ME7.8 can't control VTGs without a little help.

GT3's intake manifold.
Not an big issue actually, just requires completely different approach to tuning the engine. It has bigger volume than GT2's so the "expansion intake manifold principle" must be forgotten (because intake air already expands after the TB -and again compresses in runners-, not in combustion chambers) and go to "normal style" tuning and for example lesser ignition advance. Some tuners seem to have already used it with impressive results. Base for the tune would be something like 997 turbo's maps.

EDIT: RS38, if you have hard data of 997's MAFs, pls PM me. I'd have use for a data sheet. Anyway you wrote earlier:

997's stock HFM can properly read air mass up to (1060 kg/h * 2,3%) *2 = 2168 kg/h where they are capped.
Stock Diagnosis will recognize short cup at 2000 kh/h or 1060kg each.

I might be willing to believe this without datasheet too, just did some search about MAFs and Hitachi HTC AFH75-01 A flows 1213 kg/h in a 73 mm housing too...

TB993tt

Pete
I imagined that the VTG had the vanes wedged open"quick and dirty" in the best position for maximum power since the Bosch MS 4 can't control vanes but like you say I may have (totally !!) misinterpreted the language on the VTG vane thing (if it was how I just stated then HTF do they control excess boost without vane control or a wastegate ?) and it may be that they are just using the VTG compressor side/wheel or something completely different.

I will try and find the answer at some stage....

Why would a VTG with fully locked open vanes be any more laggy than the equivalent conventional K24 eg (if both turbos flow correct air for 750hp at 6000rpm engine speed) ?

The only example I could find of GT3 intake used for 997tt/GT2 is by esmotor, do you have any examples online of this combo and it working properly ?

pete95zhn

I played with the settings on my car while not being limited with Motronic's limits. Vanes fully closed car had boosted idle -really!- and vanes fully open it had a normally aspirated 3.6l 24v engine...almost no boost pressure whatsoever while accelerating 0-120 kmh.
Actually factory's settings are quite nice baseline, at least lower limit provides fast spooling without unnecessary rise of EGT.

IIRC BBI has done that too on their (or built by them) racer. Esmotor's car has also proven to be really fast.

TTurbine

My previous RUF 600 997tt boosted 1.2+ bar around 19xx RPMs but the high IAT's would cause ignition and boost cut at 4th gear.. I guess it has to do something with the vanes being almost closed..

Would be interesting to have a ecu program that gradually opens the vanes & maybe fully open at top RPM..Would be interesting to know to what degree the vane opening would be considered safe for EGT and the Turbos.. but looking at the EGTs on VTG engines being north of 900 i dont think there is enough room to play with... since the limit of the EGTs are 980c..

I guess thats why most tuners who produce good acceleration numbers like to run rich so that they can open the vanes further while reducing EGTs with more fuel..






IIRC BBI has done that too on their (or built by them) racer. Esmotor's car has also proven to be really fast.[/quote]

FYI Esmotor is building engines for a very famous Euro tuner company who likes to set records

pete95zhn

Actually that's the way Motronic controls boost. Vanes are kept "closed" (Well, closed is rather incorrect term here, better would be something like "directing flow to turbine wheel" etc...) until required boost level is achived, then they're gradually opened with increasing exhaust flow so that boost pressure is maintained.

You're correct with that EGT issue, already standard engines are close to the edge. Tuners have to be very careful with programming to keep EGT in control. With increased power (=increased exhaust flow ) turbine starts to be the restricting element and when exceeding turbine's limits backpressure rises thus rising the EGT too.

TB993tt

Really ? how fascinating, is he using ES for programming or hardware/engine building as well ?

It is phenomenal how that guy ES has nailed the 100-200/60-130 measure.... his 100-200kph means best part of 1G for the duration of the ~3 second run that is massive torque.

TTurbine

From what i know he is building engines in his workshop in Turkey and sending them over to "Dortmund" for there high hp packages.... Dont know if he does the programming.. TBH i wont be suprised if he does the "baseline" programming also..

pete95zhn

Just for the giggles, here's max flows of HTA compressor wheels:

65HTA - 43 lb/min
68HTA - 47 lb/min

Nomak

In US EvoMs use it 4.0l and Proto use in 3.8 and 4.3 engines. It is look that gt3 intake manifold works good on stroker engines +4.0l

Nomak

wOw. So ES built engines for 9ff now?
I'm shocked!

GT

oh god..

pete95zhn

Rather general statement in this thread, would you please be more precise...

Nomak

lol