RPI plus Resonator delete-fast
09-08-2010, 04:49 PM
#1
So I gave up on my intake mod for now as I got a quote and was 400 just to fab the box and that was for one design so no way I could do trial and error. STuck with rpi scoop, bmc filter and normal box
I have had RPI exhaust fora few months now and loved everything about it but never did notice an increase in power--more the sound was great.
Then got the bms powerbox tune and felt the car pick up some power and some faster reving/better throttle response-at this point I think the three things complicated the tune-a bit more air intake, a bit more exhaust outlet and a bit richer fuel from the powerbox.
Well last weekend I decided to take out my resonatnor (i have a 530 so just have 2 small cats and a resontator. I deleted the resonator and replaced it with a single stainless steel 2.5 inch diameter pipe that exactly matches the RPI 2.5 diameter. Stock was 2.75 piping and then the huge baffled restrictive resontator. Those who dont think the resonator is not restrictive, take it off and have a look-it is huge inside for one--so major slow flow, it has all sorts of turns and baffles-basically is there to muffle sound not flow.
So immediatly the effect on the car was absolutely night and day. Hard to describe but when full thrttle at redline it revved and pullled so much faster and than when changing gears at redline it was immediate with continuing power--I suspect what that translates to is the increase in bottom end power from faster flowing exhaust through less restrictive smaller diameter piping. Some call that "losing backpressure" which you are but now the gases flow quickly.
The e60 n52 exhaust system is the best I have ever seen-it has the straightest course out the engine manifolds, down straight through the cats and really is one long pipe to the end then to the muffler which is convoluted. Once that is gone and an RPI is on-it and the resonator is replaced, it is one long straight pipe with no turns or twists hardly so the low end power is so proimnent.
The sound is also just awesome. My favorite mod so far with the RPI--makes so much more out of the RPI-they should have included it as a package, just made their exhaust longer to go all the way back to the cats which I essentially did by using my own piping. No bends needed or anything.
I am willing to bet they would have gained another 10hp on the bottom end with the 2.5 inch pipes to the cats.
I have had RPI exhaust fora few months now and loved everything about it but never did notice an increase in power--more the sound was great.
Then got the bms powerbox tune and felt the car pick up some power and some faster reving/better throttle response-at this point I think the three things complicated the tune-a bit more air intake, a bit more exhaust outlet and a bit richer fuel from the powerbox.
Well last weekend I decided to take out my resonatnor (i have a 530 so just have 2 small cats and a resontator. I deleted the resonator and replaced it with a single stainless steel 2.5 inch diameter pipe that exactly matches the RPI 2.5 diameter. Stock was 2.75 piping and then the huge baffled restrictive resontator. Those who dont think the resonator is not restrictive, take it off and have a look-it is huge inside for one--so major slow flow, it has all sorts of turns and baffles-basically is there to muffle sound not flow.
So immediatly the effect on the car was absolutely night and day. Hard to describe but when full thrttle at redline it revved and pullled so much faster and than when changing gears at redline it was immediate with continuing power--I suspect what that translates to is the increase in bottom end power from faster flowing exhaust through less restrictive smaller diameter piping. Some call that "losing backpressure" which you are but now the gases flow quickly.
The e60 n52 exhaust system is the best I have ever seen-it has the straightest course out the engine manifolds, down straight through the cats and really is one long pipe to the end then to the muffler which is convoluted. Once that is gone and an RPI is on-it and the resonator is replaced, it is one long straight pipe with no turns or twists hardly so the low end power is so proimnent.
The sound is also just awesome. My favorite mod so far with the RPI--makes so much more out of the RPI-they should have included it as a package, just made their exhaust longer to go all the way back to the cats which I essentially did by using my own piping. No bends needed or anything.
I am willing to bet they would have gained another 10hp on the bottom end with the 2.5 inch pipes to the cats.
09-08-2010, 04:59 PM
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I've done resonator delete on my 525 with supersprint backbox but I felt a loss in low end power and slower acceleration times 0-60 and had it put back on altho the sound was great...
09-08-2010, 09:25 PM
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So I gave up on my intake mod for now as I got a quote and was 400 just to fab the box and that was for one design so no way I could do trial and error. STuck with rpi scoop, bmc filter and normal box
I have had RPI exhaust fora few months now and loved everything about it but never did notice an increase in power--more the sound was great.
Then got the bms powerbox tune and felt the car pick up some power and some faster reving/better throttle response-at this point I think the three things complicated the tune-a bit more air intake, a bit more exhaust outlet and a bit richer fuel from the powerbox.
Well last weekend I decided to take out my resonatnor (i have a 530 so just have 2 small cats and a resontator. I deleted the resonator and replaced it with a single stainless steel 2.5 inch diameter pipe that exactly matches the RPI 2.5 diameter. Stock was 2.75 piping and then the huge baffled restrictive resontator. Those who dont think the resonator is not restrictive, take it off and have a look-it is huge inside for one--so major slow flow, it has all sorts of turns and baffles-basically is there to muffle sound not flow.
So immediatly the effect on the car was absolutely night and day. Hard to describe but when full thrttle at redline it revved and pullled so much faster and than when changing gears at redline it was immediate with continuing power--I suspect what that translates to is the increase in bottom end power from faster flowing exhaust through less restrictive smaller diameter piping. Some call that "losing backpressure" which you are but now the gases flow quickly.
The e60 n52 exhaust system is the best I have ever seen-it has the straightest course out the engine manifolds, down straight through the cats and really is one long pipe to the end then to the muffler which is convoluted. Once that is gone and an RPI is on-it and the resonator is replaced, it is one long straight pipe with no turns or twists hardly so the low end power is so proimnent.
The sound is also just awesome. My favorite mod so far with the RPI--makes so much more out of the RPI-they should have included it as a package, just made their exhaust longer to go all the way back to the cats which I essentially did by using my own piping. No bends needed or anything.
I am willing to bet they would have gained another 10hp on the bottom end with the 2.5 inch pipes to the cats.
I have had RPI exhaust fora few months now and loved everything about it but never did notice an increase in power--more the sound was great.
Then got the bms powerbox tune and felt the car pick up some power and some faster reving/better throttle response-at this point I think the three things complicated the tune-a bit more air intake, a bit more exhaust outlet and a bit richer fuel from the powerbox.
Well last weekend I decided to take out my resonatnor (i have a 530 so just have 2 small cats and a resontator. I deleted the resonator and replaced it with a single stainless steel 2.5 inch diameter pipe that exactly matches the RPI 2.5 diameter. Stock was 2.75 piping and then the huge baffled restrictive resontator. Those who dont think the resonator is not restrictive, take it off and have a look-it is huge inside for one--so major slow flow, it has all sorts of turns and baffles-basically is there to muffle sound not flow.
So immediatly the effect on the car was absolutely night and day. Hard to describe but when full thrttle at redline it revved and pullled so much faster and than when changing gears at redline it was immediate with continuing power--I suspect what that translates to is the increase in bottom end power from faster flowing exhaust through less restrictive smaller diameter piping. Some call that "losing backpressure" which you are but now the gases flow quickly.
The e60 n52 exhaust system is the best I have ever seen-it has the straightest course out the engine manifolds, down straight through the cats and really is one long pipe to the end then to the muffler which is convoluted. Once that is gone and an RPI is on-it and the resonator is replaced, it is one long straight pipe with no turns or twists hardly so the low end power is so proimnent.
The sound is also just awesome. My favorite mod so far with the RPI--makes so much more out of the RPI-they should have included it as a package, just made their exhaust longer to go all the way back to the cats which I essentially did by using my own piping. No bends needed or anything.
I am willing to bet they would have gained another 10hp on the bottom end with the 2.5 inch pipes to the cats.
You don't own a BMW. You're just a forum troll.
Where's your car dude? Where's the pics? Any sound clips? Nope, nothing, nada.... ZIP.... and there never will be because you don't even own an E60.
WHEN IS SOMEONE GOING TO BAN THIS DUDE ALREADY? JESUS H CHRIST THIS IS HIS 4TH OR 5TH ACCOUNT.
BANNED MEMBER:
sleepyca31 redhwhiteblue quebecois 545oh
09-09-2010, 07:55 AM
#7
if anyone can read it is not the resonator delete-it is the piping diameter change to smaller diameter piping which RPI does with their exhaust.
That is why supersprint which I had lost power because they use 3 inch piping on their muffler to attach to the stock 2.75-so if you did a resonator delete you probably attached 3 inch piping to it which lose huge low end torque.
It is all about pipe diameter but most people on here cant think beyond simple terms-a resonator delete is not a resonator delete-it is all about what you replace it with.
You cannot do an x pipe as you only go into a single side exhaust. You need a dual exhaust or dual pipes running to one side to have an x pipe and you would need to design a completely fabbed system.
That is why I had proven loss with supersprint and remus-they use 3 inch piping. The large piping doesnt flow-that is why RPI designs their exhaust with 2.5 inch piping-its smaller than stock-ever wonder why theirs is the only exhaust to show power gain-its teh size of pipe-all mufflers are straight through design-it is the size of teh piping going through.
The 10 hp I was saying would have gained TOTAL with a rpi muffler and resonator delete with replacing all piping with 2.5 inch-basically a cat back system including a y pipe and one long 2.5 inch pipe connecting to an RPI exhaust-which wuld make it a pure catback.
Resonator probably has a 4 or 5 inch diameter inside so you can imagine gases running from the engine through cats, through 2 small 2 inch pipes at fast velocity, hit the resonator of a big 5 inch space with baffles-the amount of velocity lost is not easily picked up again when it leaves the resonator. By removing this you get rid of the loss of mommentum and velocity and even add to it with smaller piping--
Again bmw especially in the 5 and 7 series does things for quietnesss-the 330i is way louder than the 5 series. Doesnt mean the exhaust is always designed for best power-it is hella quiet but has room to perform and this opens up that performance and sounds amazing!
That is why supersprint which I had lost power because they use 3 inch piping on their muffler to attach to the stock 2.75-so if you did a resonator delete you probably attached 3 inch piping to it which lose huge low end torque.
It is all about pipe diameter but most people on here cant think beyond simple terms-a resonator delete is not a resonator delete-it is all about what you replace it with.
You cannot do an x pipe as you only go into a single side exhaust. You need a dual exhaust or dual pipes running to one side to have an x pipe and you would need to design a completely fabbed system.
That is why I had proven loss with supersprint and remus-they use 3 inch piping. The large piping doesnt flow-that is why RPI designs their exhaust with 2.5 inch piping-its smaller than stock-ever wonder why theirs is the only exhaust to show power gain-its teh size of pipe-all mufflers are straight through design-it is the size of teh piping going through.
The 10 hp I was saying would have gained TOTAL with a rpi muffler and resonator delete with replacing all piping with 2.5 inch-basically a cat back system including a y pipe and one long 2.5 inch pipe connecting to an RPI exhaust-which wuld make it a pure catback.
Resonator probably has a 4 or 5 inch diameter inside so you can imagine gases running from the engine through cats, through 2 small 2 inch pipes at fast velocity, hit the resonator of a big 5 inch space with baffles-the amount of velocity lost is not easily picked up again when it leaves the resonator. By removing this you get rid of the loss of mommentum and velocity and even add to it with smaller piping--
Again bmw especially in the 5 and 7 series does things for quietnesss-the 330i is way louder than the 5 series. Doesnt mean the exhaust is always designed for best power-it is hella quiet but has room to perform and this opens up that performance and sounds amazing!
09-09-2010, 08:10 AM
#9
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My Ride: 2006 530i
You don't own a BMW. You're just a forum troll.
Where's your car dude? Where's the pics? Any sound clips? Nope, nothing, nada.... ZIP.... and there never will be because you don't even own an E60.
WHEN IS SOMEONE GOING TO BAN THIS DUDE ALREADY? JESUS H CHRIST THIS IS HIS 4TH OR 5TH ACCOUNT.
BANNED MEMBER:
sleepyca31 redhwhiteblue quebecois 545oh
Where's your car dude? Where's the pics? Any sound clips? Nope, nothing, nada.... ZIP.... and there never will be because you don't even own an E60.
WHEN IS SOMEONE GOING TO BAN THIS DUDE ALREADY? JESUS H CHRIST THIS IS HIS 4TH OR 5TH ACCOUNT.
BANNED MEMBER:
sleepyca31 redhwhiteblue quebecois 545oh
this for reals? to funny!
