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Discussion Starter #1
This has obviously been beat to death but I am not finding an answer to my specific inquiry. Stock t.b. Is 2.75" in diameter. SRT intake is 3.5"-4" depending on when it was made and requires the piggy back. Joez and PLP intakes are 3" in diameter. I am going to fabricate my own intake here, I have plenty of 3.25" aluminum piping. My question is, will the 3.25" be too big to run without a standalone/tune? I also don't want to shift my power to the top end and lose the low end pep. Any thoughts on 3.25" or should I play it safe and stick with 3"?
 

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Unless you can tune for the MAF to be in a larger diameter, you might as well stick with stock size tube. The ECU is programmed with the MAF to be in a certain size, so it knows the exact amount of air it can flow at a given time. If you change the diameter without tuning for it, your MAF readings will be outta wack and it'll cause a number of issues.
 

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Discussion Starter #3
I should have specified I am keeping the factory airbox and maf on the airbox. This is a post maf intake like the joez.
 

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I'm that case, I don't think it'll matter. The diameter at the MAF is going to be your bottleneck, whatever after won't matter too much. Within reason of course, if you go too big, you'll get an area of low pressure when you open the throttle and it'll give you hesitation until all the air can get moving. Personally, I'd stay at stock size or pretty damn close as possible. I would also stick to some sort of plastic or resin for the tube instead of metal. The intake tube sits right over the exhaust, so logic states (in my head at least), that the metal would heat soak and raise intake temps.
 

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Discussion Starter #5
Thank you. I will probably stick with the 3" Joez size. My intake temp stays pretty cool except when idling. I am going to fab a heat shield here soon. I need to finish the cardboard template.
 

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I saw a pretty trick heat shield on Figs website...

 

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Discussion Starter #7
🤙 I had come across that as well but the price! Ha. I have some scrap metal that will work. Maybe a little thicker than that. Definitly following the mounting points for that though. Pays to never throw anything away.
 
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