Header Question -Tune?
04-01-2013, 01:13 PM
#1
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Year: 1999
Engine: 4.0
Header Question -Tune?
I have an exhaust leak on the Manifold/Header
If I put an aftermarket Header on, do I need a Tune or will it
bolt right on, no tune needed - Will it code?
Also curious if I do a High Flow Cat and Muffler at the same time
will I need a Tune?
Will it code the 02 sensors
Tks
Will
If I put an aftermarket Header on, do I need a Tune or will it
bolt right on, no tune needed - Will it code?
Also curious if I do a High Flow Cat and Muffler at the same time
will I need a Tune?
Will it code the 02 sensors
Tks
Will
04-01-2013, 02:07 PM
#3
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I thought these were sd motors?
changing anything regarding intake or exhaust will alter the afr. I'd think ESP something like a manifold to header swap. I know it leaned my ls1 car WAY out doing such. and that was with a maf...
sd motors are like carbs in a big way. I'm pretty sure the o2s can only change fueling like +\- 3% or whatever.
changing anything regarding intake or exhaust will alter the afr. I'd think ESP something like a manifold to header swap. I know it leaned my ls1 car WAY out doing such. and that was with a maf...
sd motors are like carbs in a big way. I'm pretty sure the o2s can only change fueling like +\- 3% or whatever.
Last edited by s346k; 04-01-2013 at 02:34 PM.
04-01-2013, 02:49 PM
#5
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I thought these were sd motors?
changing anything regarding intake or exhaust will alter the afr. I'd think ESP something like a manifold to header swap. I know it leaned my ls1 car WAY out doing such. and that was with a maf...
sd motors are like carbs in a big way. I'm pretty sure the o2s can only change fueling like +\- 3% or whatever.
changing anything regarding intake or exhaust will alter the afr. I'd think ESP something like a manifold to header swap. I know it leaned my ls1 car WAY out doing such. and that was with a maf...
sd motors are like carbs in a big way. I'm pretty sure the o2s can only change fueling like +\- 3% or whatever.
tune after headers...
Will
04-01-2013, 02:52 PM
#6
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looking into swapping my jeep. I just sold my 99 ws6 2 weeks ago.
04-01-2013, 02:54 PM
#7
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then you already know the answer. these are sd motors. best you could do is verify with a wideband. are you a vendor on tech? I don't do lsex parts for a living but I've owned multiple lsx powered cars and dealt with them about 10 years now. love em.
looking into swapping my jeep. I just sold my 99 ws6 2 weeks ago.
looking into swapping my jeep. I just sold my 99 ws6 2 weeks ago.
I can do a Corvette half asleep, but I don't know squat about these Jeep straight 6's
Will
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04-01-2013, 04:08 PM
#9
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04-01-2013, 05:15 PM
#10
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Just put it on.................
04-01-2013, 10:55 PM
#13
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Engine: 4.0L OBD-II
You only need to tune the 4.0 if you do a stroker or super/turbocharge it... Intakes and exhausts are called "bolt on" for a reason
04-02-2013, 04:15 AM
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they are called "bolt ons" because they literally bolt on. not because of how they affect the engine. I'd like to see someone verify with a wideband what actually happens when doing mods like this, just to see. as stated earlier, putting bolt ons on my ls1 car took it from a solid 12.8 afr @ wot to 14.7 at only 2800 rpm. bolt ons or not that is not safe or right. the lean condition also caused 8* spark knock. also all below 3k rpm.
04-02-2013, 06:31 AM
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they are called "bolt ons" because they literally bolt on. not because of how they affect the engine. I'd like to see someone verify with a wideband what actually happens when doing mods like this, just to see. as stated earlier, putting bolt ons on my ls1 car took it from a solid 12.8 afr @ wot to 14.7 at only 2800 rpm. bolt ons or not that is not safe or right. the lean condition also caused 8* spark knock. also all below 3k rpm.
As stated by Salad, the only time you need to increase injector size is when using forced induction or stroking it to 4.6 + liters.