Disapointing Dyno Test
02-11-2008, 07:56 PM
#46
Race Car
Yours is there. Follow hose from the air pump to the front of the car. The valve is hidden in your picture behind hoses. If you did not have the valve or it was not connected, you would get a CEL.
02-11-2008, 08:49 PM
#48
Race Car
Cory. Put your beer down and zoom in on the picture. Your hose does in fact go to the valve which you cannot see because of the other hoses on top of it. Yours is coming in more from the side. My picture is taken from beneath. Yours is not.
Trust me. If the SAI was not connected properly, the computer woud tell you. As to the tuner flap, if your resonnance system is not connected properly, the computer will not tell you about it.
02-11-2008, 09:27 PM
#50
Drifting
Join Date: Jul 2005
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There were no issue during my dyno, have the experts you speak of ever dyno'd their 996 before?
Thanks folks for all the feed backs. My car is not a tip, it's a 6 speed. Also, the allignment of the wheels on the dyno rolls were good, so there is probably not a big loss due to miss allignment slippage. The motor lid was closed, so it might gotten hot under the lid, causing loss of HP. With the car running and the spoiler up, the motor compartment temperature is very low, and virtually not affected by exhaust and motor heat. This might be one explanation, but not all. The peak and the dip on 5500rpm and 5800rpm are caused by the VarioRam opening, but the drop of 30HP is too much. Also the drop of in HP above 6375rpm is strange. Could it be some kind of fuel starvation or air leak in the intake manifold?
The plenum mod is home made, but if the plenum modifications advertised for $8-900 are working, then my $5 mod is working too, the modification to air flow pattern is the same (Y-shaped plenum rather than T-shaped, with less turbulense and more laminar (and increased) air flow).
During the last week end's DE, the car perfomed just as well as other Carrera's, I can still kee up with 997S's on the main straight on TWS.
Some "experts" say it's the PSM that kicks in, because the front wheels are not turning, but I don't have PSM or any traction control (thank God...). But the ABS warning light came on during the dyno run, could that affect the ECU and upset the power output? Some "experts" I talked to last week end at the DE, said that the 996 is impossible to dyno correctly, due to ECU issues with only rear wheels turning. Any idea folks???
The plenum mod is home made, but if the plenum modifications advertised for $8-900 are working, then my $5 mod is working too, the modification to air flow pattern is the same (Y-shaped plenum rather than T-shaped, with less turbulense and more laminar (and increased) air flow).
During the last week end's DE, the car perfomed just as well as other Carrera's, I can still kee up with 997S's on the main straight on TWS.
Some "experts" say it's the PSM that kicks in, because the front wheels are not turning, but I don't have PSM or any traction control (thank God...). But the ABS warning light came on during the dyno run, could that affect the ECU and upset the power output? Some "experts" I talked to last week end at the DE, said that the 996 is impossible to dyno correctly, due to ECU issues with only rear wheels turning. Any idea folks???
02-11-2008, 10:56 PM
#51
Race Car
Yes, I see the pod you are referring to. No, I did not connect the butterfly to that particular pod.
Second, clearly in your pic I see a hose with a vacuum operated valve using a spring clamp going over the top of a gold part (dont know the name) on the right side of the vacuum pod.
In my second pic, I do not have any hoses, especially that large traveling over the top of the part next to the vacuum pod as your pic shows.
That is my point. If there is a different configuration between the two, that would explain why my resonance valve was attached to a different vacuum source.
Second, clearly in your pic I see a hose with a vacuum operated valve using a spring clamp going over the top of a gold part (dont know the name) on the right side of the vacuum pod.
In my second pic, I do not have any hoses, especially that large traveling over the top of the part next to the vacuum pod as your pic shows.
That is my point. If there is a different configuration between the two, that would explain why my resonance valve was attached to a different vacuum source.
02-11-2008, 11:08 PM
#52
Race Car
Yes, I see the pod you are referring to. No, I did not connect the butterfly to that particular pod.
Second, clearly in your pic I see a hose with a vacuum operated valve using a spring clamp going over the top of a gold part (dont know the name) on the right side of the vacuum pod.
In my second pic, I do not have any hoses, especially that large traveling over the top of the part next to the vacuum pod as your pic shows.
That is my point. If there is a different configuration between the two, that would explain why my resonance valve was attached to a different vacuum source.
Second, clearly in your pic I see a hose with a vacuum operated valve using a spring clamp going over the top of a gold part (dont know the name) on the right side of the vacuum pod.
In my second pic, I do not have any hoses, especially that large traveling over the top of the part next to the vacuum pod as your pic shows.
That is my point. If there is a different configuration between the two, that would explain why my resonance valve was attached to a different vacuum source.
The tuning flap MUST be connected to the electric changeover valve (lower circle) There are 2 ports on the valve. The one that is closed when deactivated is connected to the vacuum source which MUST be the resevior, directly or indirectly. The other port, which is open when deactivated is connected to the tuning flap. Thee is no other possible way of connecting the tuning flap if you want it to work as designed. The flap needs vacuum at times when the engine is not supplying any.
You can test to see if things are hooked up properly by doing this:
Have someone sit in the driver's seat. Go to the engine compartment and look at the tuning flap pivot point on the back crossover tube. Have the person turn the key to the ON position. You should observe the flap moving to the closed position and then back again.
02-12-2008, 10:54 AM
#53
Racer
Tippy, you need to listen to 99. The secondary plenum flap is connected to the solenoid valve mounted on the intake manifold near the alternator. This solenoid is actuated between 3120 and 5120 rpm if the throttle is open more than 30%. The vacuum supply for the solenoid needs to be connected to the black vacuum reservoir as indicated by '99 since under the conditions when the flap is actuated, intake vacuum is low, thus if you connect it directly to the vacuum port on the intake manifold the flap will not close properly thus reducing performance. The only two vacuum sources to be directly connected to the intake manifold are the vacuum source for the fuel pres. reg. and the one way black/white check valve that supplies vacuum to the black reservoir allowing maintence of vacuum under all engine ranges for all other vacuum operated systems on the engine, such as the solenoid for the secondary plenum flap and the air injection system.
There are no differences in this in the different years, I have a '99 3.4, a 2004 3.6 and a 2005 3.6 X51 in the garage right now and all are identical. If your intake has dual plenums then it must be plumbed this way in order to operate correctly.
Todd
There are no differences in this in the different years, I have a '99 3.4, a 2004 3.6 and a 2005 3.6 X51 in the garage right now and all are identical. If your intake has dual plenums then it must be plumbed this way in order to operate correctly.
Todd
02-12-2008, 11:23 AM
#54
Race Car
HOW MANY TIMES DID I SAY THAT IN MY POST!!!!!IT DOES NOT TIE DIRECTLY INTO THE VACUUM POD IN THE BACK OF THE MOTOR LIKE '99 SIAD BUT ABOVE THE ALTERNATOR LIKE YOU SAID. I REMEMBER THIS VIVIDLY AND STATED THIS NUMEROUS TIMES.OMG
02-12-2008, 11:38 AM
#55
Race Car
It was you who started with the wrong information by stating "The resonance valve is vacuum operated, it should be fully open the second you drop the throttle". You also stated that the vacuum line was connected to the brake booster port which I told you was wrong.
Rather than trying to dispprove what I said, READ what I said and learn from it
02-12-2008, 11:41 AM
#56
Race Car
02-12-2008, 11:47 AM
#57
Race Car
02-12-2008, 11:49 AM
#58
Drifting
I'm not sure if the tuning valve is connected to the electric changeover valve.
Hell, I'm not even sure if the shin bone's connected to the knee bone.
I can, however, say with a high degree of certainty that your engine bay needs a thorough cleaning 1999Porsche911. I have seen Ford Pintos circa 1970 which have had shinier engines.
Hell, I'm not even sure if the shin bone's connected to the knee bone.
I can, however, say with a high degree of certainty that your engine bay needs a thorough cleaning 1999Porsche911. I have seen Ford Pintos circa 1970 which have had shinier engines.
Last edited by DreamCarrera; 02-13-2008 at 02:24 AM.
02-12-2008, 11:50 AM
#59
Race Car
