Headers: no re-tune required?
#1
Headers: no re-tune required?
OK, so I placed my order for some Pypes Long Tube headers from Brenspeed.
I already have a tune for my C&L CAI from them, but I thought for sure that they would send me a new tune to take advantage of the headers. However, I was told that no re-tune is needed and to just bolt them on and go.
I find this kind of odd because my friend just put headers on his G8 and Livernois didn't think twice about sending him an updated tune...
Thoughts or Comments?
Thanks!
I already have a tune for my C&L CAI from them, but I thought for sure that they would send me a new tune to take advantage of the headers. However, I was told that no re-tune is needed and to just bolt them on and go.
I find this kind of odd because my friend just put headers on his G8 and Livernois didn't think twice about sending him an updated tune...
Thoughts or Comments?
Thanks!
#3
depends on the style of the headers
1. O2 sensors are in the same spot = no tune required.
1. O2 sensors are in the same spot = no tune required.
a tune will maximize the gains of course.
but a tune is not required.
2. O2 sensor are moved and the cables are longer, or jumpers are used.but a tune is not required.
moving the O2 sensors, or changing their wire lenght will change the pulse timing.
the PCM is expecting the signal from those sensors at specific intervals.
so a tune is required to correct this. not to mention you will actually see a benefit from the LT's being installed.
the PCM is expecting the signal from those sensors at specific intervals.
so a tune is required to correct this. not to mention you will actually see a benefit from the LT's being installed.
#4
what kind of headers are they? shorties, i don't believe but don't quote me, don't need a code becuase the o2 does not move, however, i would still get the tune to max the performance. LTs will need a tune since the o2's are no longer there
#5
I spoke with one of the guys from Brenspeed a while back and since the 02 sensors are already off in the tune I have loaded currently no retune would be necessary when I put on the LT/OR-X.
I actually haven't heard of power gains from a new tune after only an exhaust set up change- what's the consensus here?
I actually haven't heard of power gains from a new tune after only an exhaust set up change- what's the consensus here?
#7
Get the details correct here. You dont need a tune with longtubes unless you get a DTC. The most common DTC is P0155 I believe, which is O2 heater circuit related. As stated it is caused by a change in the distance of the FRONT O2s.
You can turn off the back O2 sensors but you cant turn off the front O2 sensors. These need to be adjusted in the tune if you get the DTC. Turning off the rear O2 sensors wont have any effect on the DTC code for the front O2 sensors. People turn off the rear O2 sensors when the install an off-road pipe with NO cats.
As far as adjusting the performance you wont see much performance difference between the headers with or without a tune.
Brenspeed dyno tuned my car so the air fuel was 11.5 when I had stock manifolds and H-pipe. After I installed the 1.75" Kooks longtubes and 3" hi-flo catted X-pipe we tested the air fuel It was still 11.5 after the header installation.
So we re-tuned for the DTC and made minor adjustments and saw 25 RWHPHP/45 RWTQ increase but there was no change to air fuel ratio from exhaust change.
You can turn off the back O2 sensors but you cant turn off the front O2 sensors. These need to be adjusted in the tune if you get the DTC. Turning off the rear O2 sensors wont have any effect on the DTC code for the front O2 sensors. People turn off the rear O2 sensors when the install an off-road pipe with NO cats.
As far as adjusting the performance you wont see much performance difference between the headers with or without a tune.
Brenspeed dyno tuned my car so the air fuel was 11.5 when I had stock manifolds and H-pipe. After I installed the 1.75" Kooks longtubes and 3" hi-flo catted X-pipe we tested the air fuel It was still 11.5 after the header installation.
So we re-tuned for the DTC and made minor adjustments and saw 25 RWHPHP/45 RWTQ increase but there was no change to air fuel ratio from exhaust change.
#8
I spoke with one of the guys from Brenspeed a while back and since the 02 sensors are already off in the tune I have loaded currently no retune would be necessary when I put on the LT/OR-X.
I actually haven't heard of power gains from a new tune after only an exhaust set up change- what's the consensus here?
I actually haven't heard of power gains from a new tune after only an exhaust set up change- what's the consensus here?
So according to zkiller- you can get more HP and TQ just by changing the exhaust without getting it tuned (I understand A/F ratio's, O2 sensors, DTC's and turning of the rear O2 sensors etc. that you stated above except the tune thing?) I know where you want the A/F ratio to be but doesn't something have to be toyed with in the tune to get the most out of the mod while keeping the same A/F ratio?
Basically if you get a code you get the tuner to correct it....if no codes your fine? nothing more needs to be done?
Last edited by mygt500; 10-22-2009 at 05:55 PM.
#9
I'm currently shopping LT headers and talked to two local tuners here in Houston and both said you can run them without updating the tune but they both highly recommended getting a new tune... the one tuner said to expect an additional 10-15hp with the tune while the other said 20hp.
I'm still trying to figure out if I should go with 1 3/4 tubing or 1 5/8 tubing?
I'm still trying to figure out if I should go with 1 3/4 tubing or 1 5/8 tubing?
#10
I'm currently shopping LT headers and talked to two local tuners here in Houston and both said you can run them without updating the tune but they both highly recommended getting a new tune... the one tuner said to expect an additional 10-15hp with the tune while the other said 20hp.
I'm still trying to figure out if I should go with 1 3/4 tubing or 1 5/8 tubing?
I'm still trying to figure out if I should go with 1 3/4 tubing or 1 5/8 tubing?
1 5/8 if your going to stay naturally aspirated
1 3/4 if you think ull put a SC or turbos on some day (or some other way of greatly inc the hp)
I'm sure someone here can give you a "number" (eg. under XXX hp, 1 5/8, above XXX hp, 1 3/4)
I'll let you know in about 2 weeks how I like my Pypes (shipped from Brenspeed today for the coating company...)