Gt2 Small Boost Leak
#31
11-10-2012, 11:44 AM
ahh, prego. plus. you've got better food/cars and ( maybe..) women. off the shelf, i mean 
#32
11-10-2012, 11:50 AM
[quote=cosworth;3687994]
Right ..BUT without electronic sensor ECU control...if you have a Turbine that pump air at the same speed in summer and in winter then YES you will see higher BOOST in winter when the air is cold because cold air is more dense that hot air..this is a physical science rule.
BUT starting from intake air temperature ,the MOTRONIC ECU calculate the amount of air the engine need to produce a certain power and torque.
This Power/torque "goal" of we say 462 BHP on stock GT2 , remain the same in SUMMER and WINTER , so the ECU works for the ENGINE produce much the same 462 BHP at 0 (zero) celsius degree in January and at 40 celsius degree in AUGUST.
IS ALL around the air density that is much dense when cold and less dense when hot , so to produce the same engine combustion , more air is needed when hot and less air is needed when cold.
So if at 20 celsius degree to produce 462 BHP the engine need we say 100 parts of AIR and the turbine must pump at 0.8 BAR to reach this 100 parts of AIR , when 40 degree it needs 120 parts of AIR and turbine must pump at 0.9 BAR to reach this 120 parts ......otherwise at 0 degree it needs 80 parts of AIR and the turbine must pump only 0.7 BAR.
The calculation of how much air is needed in the different weathers is do from the ECU by the MAF readings (MAF reads temperature and density of the intake air) , so having this reading , the ECU from N75 valve regulate the wastegate actuators work to open and close the wastegate valve.
So when hot the ECU by N75 and actuators order to wastegate stay CLOSE much time because the turbine must run fast to produce 0.9 Bar of boost , otherwise when is cold the ECU order to wastegate stay OPEN much time because the turbine must run less fast since it must to produce only 0.7 Bar of boost.
SURE ...This is only what there is in my knowledge
Sorry to say ,I know that practical and theory are two different things..
I know if you put your car under full load in 4th gear on a hot day compared to a cold day you will gain a bit of boost..It a proven real world fact..Have YOU ever done that?
Look up all the things on Boost Creep..And thats why 1 bar wastegates can not control cold weather that well also..
Cold air is more dense then hot air..Sensors can only do so much.
But to each his own in theories..Its all good..
Right ..BUT without electronic sensor ECU control...if you have a Turbine that pump air at the same speed in summer and in winter then YES you will see higher BOOST in winter when the air is cold because cold air is more dense that hot air..this is a physical science rule.
BUT starting from intake air temperature ,the MOTRONIC ECU calculate the amount of air the engine need to produce a certain power and torque.
This Power/torque "goal" of we say 462 BHP on stock GT2 , remain the same in SUMMER and WINTER , so the ECU works for the ENGINE produce much the same 462 BHP at 0 (zero) celsius degree in January and at 40 celsius degree in AUGUST.
IS ALL around the air density that is much dense when cold and less dense when hot , so to produce the same engine combustion , more air is needed when hot and less air is needed when cold.
So if at 20 celsius degree to produce 462 BHP the engine need we say 100 parts of AIR and the turbine must pump at 0.8 BAR to reach this 100 parts of AIR , when 40 degree it needs 120 parts of AIR and turbine must pump at 0.9 BAR to reach this 120 parts ......otherwise at 0 degree it needs 80 parts of AIR and the turbine must pump only 0.7 BAR.
The calculation of how much air is needed in the different weathers is do from the ECU by the MAF readings (MAF reads temperature and density of the intake air) , so having this reading , the ECU from N75 valve regulate the wastegate actuators work to open and close the wastegate valve.
So when hot the ECU by N75 and actuators order to wastegate stay CLOSE much time because the turbine must run fast to produce 0.9 Bar of boost , otherwise when is cold the ECU order to wastegate stay OPEN much time because the turbine must run less fast since it must to produce only 0.7 Bar of boost.
SURE ...This is only what there is in my knowledge
I know if you put your car under full load in 4th gear on a hot day compared to a cold day you will gain a bit of boost..It a proven real world fact..Have YOU ever done that?
Look up all the things on Boost Creep..And thats why 1 bar wastegates can not control cold weather that well also..
Cold air is more dense then hot air..Sensors can only do so much.
But to each his own in theories..Its all good..
#33
11-10-2012, 12:07 PM
[quote=johnspeed;3688021]
Sorry to say ,I know that practical and theory are two different things..
I know if you put your car under full load in 4th gear on a hot day compared to a cold day you will gain a bit of boost..It a proven real world fact..Have YOU ever done that?
Look up all the things on Boost Creep..And thats why 1 bar wastegates can not control cold weather that well also..
Cold air is more dense then hot air..Sensors can only do so much.
But to each his own in theories..Its all good..
John I have do that and i assure to you that when my car was stock , boost read was a bit higher in hot day..
Only now Tuned and with wastegate actuator tightened as you say boost is higher in cold days also in my car.
But as you say , to each his own in theories..Its all good..
Sorry to say ,I know that practical and theory are two different things..
I know if you put your car under full load in 4th gear on a hot day compared to a cold day you will gain a bit of boost..It a proven real world fact..Have YOU ever done that?
Look up all the things on Boost Creep..And thats why 1 bar wastegates can not control cold weather that well also..
Cold air is more dense then hot air..Sensors can only do so much.
But to each his own in theories..Its all good..
Only now Tuned and with wastegate actuator tightened as you say boost is higher in cold days also in my car.
But as you say , to each his own in theories..Its all good..
#34
11-10-2012, 12:16 PM
In any case now that here is cold and foggy , i' d like to run with my DUCATI on LA Mulholland drive
...maybe we've got better bikes but you have the better roads
#36
11-10-2012, 12:23 PM
by that, you mean an x50 car is somehow "in between" a stock k16? and a stock gt2 w 24's? not to split hairs, i just figured for the purpose of a power level conversaton, a stock 996 gt2 and an x50 ( stock ) were similarly equipped and should see similar boost. that's all my question was about. not to further obfuscate the ( non ) issue.
#37
11-10-2012, 12:26 PM
[quote=cosworth;3688024]
John I have do that and i assure to you that when my car was stock , boost read was a bit higher in hot day..
Only now Tuned and with wastegate actuator tightened as you say boost is higher in cold days also in my car.
But as you say , to each his own in theories..Its all good..
for my understanding most tuned tt are in blind calibration and maf is at 5volt... (around 4000rpm)at this situation ecu cant make a load calculated boost and ignore load...result higher boost at cold conditions....only my theorie....
John I have do that and i assure to you that when my car was stock , boost read was a bit higher in hot day..
Only now Tuned and with wastegate actuator tightened as you say boost is higher in cold days also in my car.
But as you say , to each his own in theories..Its all good..
#38
11-10-2012, 12:27 PM
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Join Date: Oct 2012
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If I would do it from scratch I'd leave the stock air box but put a good filter in there, diverter valves to prevent boost leak, 3" exhaust with 100C cats, 20G upgrade(18G for those of you with the K16s, 20G wheel won't work on the Turbos unless they have the X50 package or GT2s which I have), injectors, water\meth injection, and a tune. The water\meth should be a good substitute for an intercooler upgrade at a fraction of the cost of the intercoolers but if you can do both, even better 
I have been reading the 997.2 GT2RS intercoolers are a good option for intercoolers at a reasonable price; around $1k
I think that would be right at 600 at the wheels on pump quite a bit more on higher boost with race gas.
Next step will be the 4.0 motor build. Muahahahaha
I have been reading the 997.2 GT2RS intercoolers are a good option for intercoolers at a reasonable price; around $1kI think that would be right at 600 at the wheels on pump quite a bit more on higher boost with race gas.
Next step will be the 4.0 motor build. Muahahahaha
#39
11-10-2012, 12:29 PM
Winni i also thought that X50 and Gt2 mk1 have the same ECU map , turbos and boost level and that 12 Hp difference 462 Vs 450 it was only by an rear exhaust a little more opened in the Gt2.
The Gt2 mk2 has a different Ecu map for 480 hp
The Gt2 mk2 has a different Ecu map for 480 hp
#40
11-10-2012, 12:29 PM
by that, you mean an x50 car is somehow "in between" a stock k16? and a stock gt2 w 24's? not to split hairs, i just figured for the purpose of a power level conversaton, a stock 996 gt2 and an x50 ( stock ) were similarly equipped and should see similar boost. that's all my question was about. not to further obfuscate the ( non ) issue.
#41
11-10-2012, 12:37 PM
x50 has same engine, same intercooler, same turbos, same muffler....boost line is a little different....
mk2 gt2 has different pistons...and a different ecu map....with a rpm and speed calculated rev limit 50rpm higher only in 6.gear....i dont understand that most tuners dont do that way and tune the map only in 6.gear for a high top speed..
#42
11-10-2012, 12:37 PM
Sure about food , ..women.. is an individual choice... about car i don't like FERRARI , GERMAN are the best
In any case now that here is cold and foggy , i' d like to run with my DUCATI on LA Mulholland drive...maybe we've got better bikes but you have the better roads
In any case now that here is cold and foggy , i' d like to run with my DUCATI on LA Mulholland drive
...maybe we've got better bikes but you have the better roads
i have an old flattrack dirt tracker 650 triumph. no moto guzzi's here lol but i would do many things to have a ducati 848! just saw one here last weekend. sweet
yes, to german cars. what's that saying? marry a german ( car ), but ( if one must
) cheat with an italian. ha.you have excellent taste in cars and streets. sorry to the OP for the thread derailment
#43
11-10-2012, 12:39 PM
x50 has same engine, same intercooler, same turbos, same muffler....boost line is a little different....
mk2 gt2 has different pistons...and a different ecu map....with a rpm and speed calculated rev limit 50rpm higher only in 6.gear....i dont understand that most tuners dont do that way and tune the map only in 6.gear for a high top speed..
mk2 gt2 has different pistons...and a different ecu map....with a rpm and speed calculated rev limit 50rpm higher only in 6.gear....i dont understand that most tuners dont do that way and tune the map only in 6.gear for a high top speed..
#44
11-10-2012, 12:44 PM
as i remember it: it's something? (lol) like 414hp k16 car and 444hp x50. can't recall porsche's stated hp estimates for the gt2 as i've never been fortunate enough to have one. not so, the x50 and tuned hybrid turbo tt.
#45
11-10-2012, 12:48 PM
How would Stock ECU map vs Flashed effect this? It must be that a flashed ecu has a set boost, and little variance? Stock on the other hand must have some variance to it.