Shorty headers for lowered 4x4

Tlee94sbc350 said:

I have the one o2 sensor before the cat. Does anyone know if I can just delete this? Or is it just best to replace.

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You need an O2 sensor or your PCM will go into open loop and throw an SES light.

Tlee94sbc350 said:

Plus the headers I received have a o2 sensor on the drivers side before the collector.( my truck manifolds did not) anyone know what thread size I need to block off that side?

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I can't remember what size the threads are, maybe someone else can chime in but, if you buy something like those JBAs, they come with a bung and plug. You can plug the bung in the header and put your O2 in the Y collector. I have a NBO2 in my header and a WBO2 in the Y for tuning but I'm running all the time on the WBO2 for now, just monitoring the NBO2.

Tlee94sbc350 said:

anyone know what thread size I need to block off that side?

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I looked on Amazon and found it's M18 X 1.5
https://www.amazon.com/Ledaut-M18X1...9Y2xpY2tSZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU=

PlayingWithTBI said:

There's a good reason for buying the more expensive Y pipes - better flow. After paying for headers why would you want to defeat their performance? The "cheap" Y pipes aren't mandrel bent and don't have a smooth transition at the collector. I bit the bullet and bought the JBA setup, nice bends and smooth collector (plus they're stainless). And don't forget a good high flow cat (if you're gonna use one).

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If I don't use a cat will my o2 sensor be thrown off with no back pressure?

I see the g9014 headers have a 2.5 inch collector diameter but these off road y pipe only has a 2.25 inch inlet. Would that be a problem?

Tlee94sbc350 said:

If I don't use a cat will my o2 sensor be thrown off with no back pressure?

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No, the TBI system only uses 1 O2 sensor for fuel trims. The Vortec has downstream cat(s) sensor(s) to ensure they are working.

Tlee94sbc350 said:

I see the g9014 headers have a 2.5 inch collector diameter but these off road y pipe only has a 2.25 inch inlet. Would that be a problem?

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No, dual 2-1/4" pipes will support up to 400HP IIRC and they flow about as much as a single 3" pipe.