Cold air intake

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Beastmo

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I have 5.3L LS and want to open it up to breath what is the best to use for that I like K&N but I hear S&B are really good too? any suggestions?
 

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How's the truck set up now? The stock truck set ups from a LS based truck are probably sufficient for what you are wanting to do. I have a KN set up on my 04 2500. The fitment never was very good. It came loose on the T-body, the filter fell off of its mount.
 

TotalyHucked

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The best setup is a box that is sealed from the engine heat but has an air inlet from outside somehow. This is how my truck is set up currently, just some 4" tubing with some silicone connectors and T-clamps, resting on the secondary battery tray from SloshTubz (ignore the blue tube, I'm going to paint it black). I plan to either build a box from sheet metal or aluminum to go around that or cut up an OBS storage box I have. It will have 3 sides and a lid, but stay open toward the front and pick up the hole in the radiator support that the original intake tube attached to.

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Unfortunately, there's not an off the shelf, bolt in cold air kit for these swapped trucks. I've also seen guys use the stock airbox from a 99-07 truck with some tubing and couplers. For the filter itself, I stay away from K&N, the oil can foul out the MAF sensor. I like dry filters. I've used many different brands, as long as it's dry.
 

Sad Sack

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I have 5.3L LS and want to open it up to breath what is the best to use for that I like K&N but I hear S&B are really good too? any suggestions?
Fram Air Hog
 

Beastmo

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It is currently setup stock air box. I know more air = more fuel but it is a hot rod truck so I don't care about that.
 

AuroraGirl

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The best setup is a box that is sealed from the engine heat but has an air inlet from outside somehow. This is how my truck is set up currently, just some 4" tubing with some silicone connectors and T-clamps, resting on the secondary battery tray from SloshTubz (ignore the blue tube, I'm going to paint it black). I plan to either build a box from sheet metal or aluminum to go around that or cut up an OBS storage box I have. It will have 3 sides and a lid, but stay open toward the front and pick up the hole in the radiator support that the original intake tube attached to.

You must be registered for see images attach


Unfortunately, there's not an off the shelf, bolt in cold air kit for these swapped trucks. I've also seen guys use the stock airbox from a 99-07 truck with some tubing and couplers. For the filter itself, I stay away from K&N, the oil can foul out the MAF sensor. I like dry filters. I've used many different brands, as long as it's dry.
the way you have done your filter is likely not helping your MAF Sensor. did you leave the screen in the mAF?

THe sensor was calibrated for a much smaller diameter tubing to the throttle body (Unless it just looks bigger?) and the filter being a cone is also a lot different than the flat one that would have delivered the air to the sensor
 

TotalyHucked

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the way you have done your filter is likely not helping your MAF Sensor. did you leave the screen in the mAF?

THe sensor was calibrated for a much smaller diameter tubing to the throttle body (Unless it just looks bigger?) and the filter being a cone is also a lot different than the flat one that would have delivered the air to the sensor
Not with this engine. The gen3 trucks did use a smaller intake tube but this is a gen4 out of an Envoy and it had a 4" tube going into the throttle body (was like 3.8 something when I measured it, close enough). It does still have the screen and it's all been tuned to work properly. It works great and IATs aren't bad when I'm moving since it's right there in the corner breathing from the core support. They do get hot sitting in traffic though, that's why I plan to build a box
 

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Not with this engine. The gen3 trucks did use a smaller intake tube but this is a gen4 out of an Envoy and it had a 4" tube going into the throttle body (was like 3.8 something when I measured it, close enough). It does still have the screen and it's all been tuned to work properly. It works great and IATs aren't bad when I'm moving since it's right there in the corner breathing from the core support. They do get hot sitting in traffic though, that's why I plan to build a box
excellent.
Didnt know the gen 4 used larger tubes
 

Ricko1966

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I have 5.3L LS and want to open it up to breath what is the best to use for that I like K&N but I hear S&B are really good too? any suggestions?
Oil impregnated filters are not good for hot wire MAF they coat the hot wire with oil and dirt create a blanket so the hot wire can no longer sense airflow accurately.I do not know if you have hot wire MAF and didn't look. I' would look for a factory airbox from a truck with a 8.1 or similiar it will flow more than enough for your 5.3 and have all the advantages of the money spent engineering it. True cold air,water intrusion etc,etc. Look at everything in the junkyard with big engines and use your brain power.
 

AuroraGirl

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Oil impregnated filters are not good for hot air MAF they coat the hot wire with oil and dirt create a blanket so the hot wire can no longer sense airflow accurately.I do not know if you have hatvwire MAF and didn't look. I' would look for a factory airbox from a truck with a 8.1 or similiar it will flow more than enough for your 5.3 and have all the advantages of the money spent engineering it. True cold air,water intrusion etc,etc. Look at everything in the junkyard with big engines and use your brain power.
yes its hot wire MAF.

The sensor is virtually unchanged most of the gen iii lifespan
 

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Oil impregnated filters are not good for hot wire MAF they coat the hot wire with oil and dirt create a blanket so the hot wire can no longer sense airflow accurately.I do not know if you have hot wire MAF and didn't look. I' would look for a factory airbox from a truck with a 8.1 or similiar it will flow more than enough for your 5.3 and have all the advantages of the money spent engineering it. True cold air,water intrusion etc,etc. Look at everything in the junkyard with big engines and use your brain power.
IIRC GM put out a TSB on this issue that's available for reading.
 

Ricko1966

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It is currently setup stock air box. I know more air = more fuel but it is a hot rod truck so I don't care about that.
I think the more air more fuel comment meant you cold burn more fuel which would make more power,that's the whole point of CAI which the factory system was anyway. Now look at your system hard is your air box and filter not capable of providing the cfm that will flow through your throttle body and MAF if it already has the CFM and it probably does changing it won't help. Change will happen when you change what is most air flow limited,whether that's is the intake box,tube,MAF,throttle body,intake,heads etc,etc.
 

AuroraGirl

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I think the more air more fuel comment meant you cold burn more fuel which would make more power,that's the whole point of CAI which the factory system was anyway. Now look at your system hard is your air box and filter not capable of providing the cfm that will flow through your throttle body and MAF if it already has the CFM and it probably does changing it won't help. Change will happen when you change what is most air flow limited,whether that's is the intake box,tube,MAF,throttle body,intake,heads etc,etc.
stock boxes on 5.3 in the gen iii are sufficient for stock engines, you have to be making engine mods to outflow it
 
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