massive power loss when i add 3" exhaust?
10-01-2006, 10:30 AM
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massive power loss when i add 3" exhaust?
my setup is a homemade one. consist of a 14B talon turbo on a meutek manifold and 2.5" charge piping.. FMIC etc.. fuel management is FMU and adjustable press regulator.. i run the car open turbo , just a small 3" pipe off turbo that points to the ground.. the car ran a 12.8 with only 11 psi like this.. im now running like 16-18 psi max.. i try to keep it around 15 for normal driving around but i went to add just a side exhaust which came off turbo and went out side of front bumper.. i used 3" piping and when i did it and went to test drive it the car was noticably slower so i took it back off. i know less backpressure is best for fast spooling but why such a big loss just from a 3 foot pipe? there was no real hard bends in it or nothing? i know my turbo is kinda small but it shouldnt have that much loss from a side pipe.. do i have to add more fuel or what? ( its on an obdo ls motor)
10-01-2006, 10:41 AM
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Re: massive power loss when i add 3" exhaust? (97grnrs)
is this a joke? your motor is destroyed (hopefully) from the fmu.
fmu = f***s motors up
Modified by tegasaurus at 1:25 PM 10/1/2006
fmu = f***s motors up
Modified by tegasaurus at 1:25 PM 10/1/2006
10-01-2006, 11:34 AM
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Re: massive power loss when i add 3" exhaust? (tegasaurus)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 97grnrs »</TD></TR><TR><TD CLASS="quote">my setup is a homemade one. consist of a 14B talon turbo on a meutek manifold and 2.5" charge piping.. FMIC etc.. fuel management is FMU and adjustable press regulator.. i run the car open turbo , just a small 3" pipe off turbo that points to the ground.. the car ran a 12.8 with only 11 psi like this.. im now running like 16-18 psi max.. i try to keep it around 15 for normal driving around but i went to add just a side exhaust which came off turbo and went out side of front bumper.. i used 3" piping and when i did it and went to test drive it the car was noticably slower so i took it back off. i know less backpressure is best for fast spooling but why such a big loss just from a 3 foot pipe? there was no real hard bends in it or nothing? i know my turbo is kinda small but it shouldnt have that much loss from a side pipe.. do i have to add more fuel or what? ( its on an obdo ls motor) </TD></TR></TABLE>
Do you mean loss from 3 inch piping? Or loss from having just a 3 foot downpipe?
Do you mean loss from 3 inch piping? Or loss from having just a 3 foot downpipe?
10-01-2006, 01:21 PM
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Re: massive power loss when i add 3" exhaust? (Mr. HYDE)
my car is not destroyed at all.. its a daily driven low 12 sec car.. it only lost power when i added the 3" exhaust , prob due to restriction or something.. i am back to running open turbo and the car is faster than b4 with more boost now too. it has nothing to do with fmu .. im just wondering why adding a 3" side pipe takes away a good amount of power as compared to open turbo .
10-01-2006, 01:26 PM
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Re: massive power loss when i add 3" exhaust? (97grnrs)
I would say it just the added backpressure being 3Inch or not. The guys who commented on the FMU when it had nothing to do with the question just wanted to sound smart.
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10-01-2006, 01:38 PM
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Re: massive power loss when i add 3" exhaust? (tegasaurus)
peopel <TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by tegasaurus »</TD></TR><TR><TD CLASS="quote">is this a joke? your motor is destroyed (hopefully) from the fmu.
fmu = f***s motors up
Modified by tegasaurus at 1:25 PM 10/1/2006</TD></TR></TABLE>
how does that help his question??
he didnt ask if his fmu has a problem,he asked about his exhaust.he is having success with his fuel management so leave him alon,dont be a dick.....
fmu = f***s motors up
Modified by tegasaurus at 1:25 PM 10/1/2006</TD></TR></TABLE>
how does that help his question??
he didnt ask if his fmu has a problem,he asked about his exhaust.he is having success with his fuel management so leave him alon,dont be a dick.....
10-01-2006, 02:44 PM
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Re: massive power loss when i add 3" exhaust? (97grnrs)
<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 97grnrs »</TD></TR><TR><TD CLASS="quote">my car is not destroyed at all.. its a daily driven low 12 sec car.. it only lost power when i added the 3" exhaust , prob due to restriction or something.. i am back to running open turbo and the car is faster than b4 with more boost now too. it has nothing to do with fmu .. im just wondering why adding a 3" side pipe takes away a good amount of power as compared to open turbo . </TD></TR></TABLE>
You run an open exhaust on your daily? I wouldn't imagine the side pipe you described as being that restrictive. Yes, it will have some effect, but it should not be as severe as it sounds to be. Have you dynoed before and after? Or, perhaps ran it at the track? Maybe because the sound is directed away from the car (as opposed to bouncing off of the ground) it seems quieter, and smoother... creating the illusion of a slower car. I don't know, but it seems that there are potentially other problems.
You run an open exhaust on your daily? I wouldn't imagine the side pipe you described as being that restrictive. Yes, it will have some effect, but it should not be as severe as it sounds to be. Have you dynoed before and after? Or, perhaps ran it at the track? Maybe because the sound is directed away from the car (as opposed to bouncing off of the ground) it seems quieter, and smoother... creating the illusion of a slower car. I don't know, but it seems that there are potentially other problems.
10-01-2006, 03:19 PM
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You say it's down on power, but you have no way to prove that the exhaust did it. Throw what you had back on there and see how it's doing instead of looking to a bunch of people on the internet for answers.
The FMU is terrible for what you're doing. A 3" exhaust should never hurt your performance. Something else is wrong (hint-hint).
The FMU is terrible for what you're doing. A 3" exhaust should never hurt your performance. Something else is wrong (hint-hint).
10-01-2006, 05:24 PM
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Re: (Snafubmx234)
nothing else is wrong with the car or setup.. im going from a open turbo to a turbo with an exhaust.. i guess im just too used to the super fast spooling and power from an open turbo.. so ill just keep it that way. i dont care what anyone says about the fmu. i spent maybe 600 on my whole setup which i made and ran a 12.8 @ 110 on only 11 psi.. thats def not bad at all. and right now i run close to 20 psi and the car is daily driven and runs strong as ever . most def will do a high 11 or very low 12 as it sits..
10-01-2006, 05:26 PM
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Re: (97grnrs)
I don't see anything wrong with your setup. Especially for the money. I know that you were running an open turbo, now you run a pipe that extends from the turbo to where exactly. Is this pipe 3 feet long, or does it tie in to a full exhaust system?
10-01-2006, 05:32 PM
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Re: (Tornadom)
well i still run open turbo ( only kept the side pipe on for about an hour and then took it off ) due to less power.. it wasnt a huge drop but it was noticable.. i guess my turbo isnt really that big so the added backpressure from the side pipe was takin a lil more away from it than if i had a bigger turbo. i dunno.. the pipe was comin off the turbo and had a 90* bend and then ran straight out side of front bumper.. not much restriction but was enough to notice compared to open turbo i guess.
10-01-2006, 05:40 PM
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Re: (97grnrs)
let me restate this
FMU
even open downpipe or full exhaust an fmu is ****.
sell it and get a chipped ecu
you could afford a full 3" exhaust but not an ecu... go figure.
FMU
even open downpipe or full exhaust an fmu is ****.
sell it and get a chipped ecu
you could afford a full 3" exhaust but not an ecu... go figure.
10-01-2006, 05:46 PM
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Re: (97grnrs)
yes you have a reason.
do you know how rich you are running with an fmu?
get it tuned, make more power and save money on gas. and you wont look like a friggin diesel truck from billowing black smoke
do you know how rich you are running with an fmu?
get it tuned, make more power and save money on gas. and you wont look like a friggin diesel truck from billowing black smoke
10-01-2006, 05:57 PM
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Re: (97grnrs)
well, youre running 20 psi on an fmu. if its a 12:1 thats 240psi on top of base fuel pressure (lets assume 42 psi) thats 282psi at the rail.
theres your problem, trust me, youre running too rich.
get an ecu and get it tuned
theres your problem, trust me, youre running too rich.
get an ecu and get it tuned
10-01-2006, 06:06 PM
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While a real tune would help, running an FMU on a D16 isn't that big of a deal. If it blows up, swap in a new one for $300. So what. Big deal. Your setup was more than that.
Your spool shouldn't be any faster with an open turbo.. I think it just sounds slower. Like everyone said run it at the track with the exhaust then take it off. Do it between runs if you have to.
Your spool shouldn't be any faster with an open turbo.. I think it just sounds slower. Like everyone said run it at the track with the exhaust then take it off. Do it between runs if you have to.
10-02-2006, 06:06 PM
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yea but the FMU has something to do with his power droping as well. the more boost the more fuel which equals ****. use the same boost with open and full exhaust and there won't really be that big of a diff if you do your exhaust right. and as said if your going to complain just get it tuned. you'll be way happier after that.
10-02-2006, 06:11 PM
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Re: (bigbadboy)
well i decided to make another side pipe. i did and it seems to be just as fast as open turbo.. maybe it was the old pipe causing too much restriction or something.. its working great now and i dont have to smell as many fumes. 3" pipe ran right out side of front bumper.
