Has anyone got dyno proof of the gains going to a full 3" exhaust?
#151
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Sorry for bringing back this thread, just want to share some info.....
Most of you didn't believe me when i mentioned that my car (as in the car that i have now) did no way in hell come without a CAT nor a primary muffler from the factory.
Turns out that the car went for some ac check-up and i asked the shop to take a look at the exhaust system......
I am GLAD to say that they did find the factory part numbers on the testpipe-area, and when i checked in the PET, it gave me the "unknown part number". Took the car to the dealership, checked the number in their system (it was NOT a PET system, some other weird system) and that part was superceeded in mid 1987 on ALL German Spec cars.
I didn't even bother asking for more details, since my main concern was finding out if anyone tampered with the exhaust system. Beside the aftermarket Borla muffler and tip on the rear, it is FULL STOCK.
Thanks to those that liked to call me a bull**** talker, it really shows how this forum is like. I am keeping the numbers to myself, those who were nice to me (anyone? LOL) could contact me offline if they are interested at all in the numbers........you guys were great!!
Most of you didn't believe me when i mentioned that my car (as in the car that i have now) did no way in hell come without a CAT nor a primary muffler from the factory.
Turns out that the car went for some ac check-up and i asked the shop to take a look at the exhaust system......
I am GLAD to say that they did find the factory part numbers on the testpipe-area, and when i checked in the PET, it gave me the "unknown part number". Took the car to the dealership, checked the number in their system (it was NOT a PET system, some other weird system) and that part was superceeded in mid 1987 on ALL German Spec cars.
I didn't even bother asking for more details, since my main concern was finding out if anyone tampered with the exhaust system. Beside the aftermarket Borla muffler and tip on the rear, it is FULL STOCK.
Thanks to those that liked to call me a bull**** talker, it really shows how this forum is like. I am keeping the numbers to myself, those who were nice to me (anyone? LOL) could contact me offline if they are interested at all in the numbers........you guys were great!!
#154
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NZ: Maybe that is why you have a screw loose, from banging your head so much!!! take a break!
Anders: That is for you to find out, i said what i had to say, no hard feelings, dont get me wrong and i am not bull****ting this one, but it didn't make me look so nice when you said what you said on page 9.
Over and out
Anders: That is for you to find out, i said what i had to say, no hard feelings, dont get me wrong and i am not bull****ting this one, but it didn't make me look so nice when you said what you said on page 9.
Over and out
#155
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Post here again Horseram and i'll close the thread.
You can PM Anders or start your own I am right and everyone else is wrong thread.
Sorry Anders...
You can PM Anders or start your own I am right and everyone else is wrong thread.
Sorry Anders...
#156
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Ok, so here is some initial exhaust back pressure "empirical" data... keep in mind I have a home made 3" cat back and a TRR SS muffler with a silencer plate.
WITH the silencer plate the EXHAUST back pressure was circa 6psi at 16psi of manifold pressure
WITHOUT the silencer the EXHAUST back pressure was circa 2psi at 16psi of manifold pressure
So we can assume at 20psi (where I intend to run) back pressure will be around 3psi (based on the rising rate seen). This is not much really, but I will be going ahead with the 3" downpipe and test pipe and vent the WG to atm. I expect this will easily eliminate back pressure all together in the exhaust, and the WHP gains of the exhaust will not be what I would call significant. A 4" exhaust looks like massive overkill and a waste of money at this stage.
The pressure sensor was placed where the O2 sensor was after the turbo.
I will have dyno proof ("empirical") of the changes in spool, torque, HP and exhaust back pressure in around a month.
WITH the silencer plate the EXHAUST back pressure was circa 6psi at 16psi of manifold pressure
WITHOUT the silencer the EXHAUST back pressure was circa 2psi at 16psi of manifold pressure
So we can assume at 20psi (where I intend to run) back pressure will be around 3psi (based on the rising rate seen). This is not much really, but I will be going ahead with the 3" downpipe and test pipe and vent the WG to atm. I expect this will easily eliminate back pressure all together in the exhaust, and the WHP gains of the exhaust will not be what I would call significant. A 4" exhaust looks like massive overkill and a waste of money at this stage.
The pressure sensor was placed where the O2 sensor was after the turbo.
I will have dyno proof ("empirical") of the changes in spool, torque, HP and exhaust back pressure in around a month.