408 stroker .. stock tpi air box?
#1
408 stroker .. stock tpi air box?
Currently I have a ls1 w/cam in my car, swapping to a 408 with heads cam intake will the stock tpi air box be restrictive should I make a cold air intake? I like the stock look and fit but if restrictive it’s gone. Thanks for any input
#2
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Car: '89 Firebird
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Re: 408 stroker .. stock tpi air box?
Waaaaay restrictive. But you can give it a try and look at your MAP sensor values at wide open throttle.
A 4 inch intake and very large filter was on the hairy edge for my 427 stroker. I had to bump up to a 5 inch intake with the LS7.
A 4 inch intake and very large filter was on the hairy edge for my 427 stroker. I had to bump up to a 5 inch intake with the LS7.
#3
TGO Supporter
Re: 408 stroker .. stock tpi air box?
This is a 408 LS2 with CNC’d LS3 heads and an aggressive cam. The CAI is 4”, which is the minimum for this motor as QuickTrip stated. You’re not going to want to chock that motor. I’m also running a dual 3” exhaust on my motor.
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#6
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Re: 408 stroker .. stock tpi air box?
If you built a ram air box to forcefeed the tpi y lid, it would work decent. The Y only flows around mid 700’s cfm. You can custom make one a bit taller like Chad Speier is doing for his 530 hp 379. But its alot of work
a good air intake is better idea tho
a good air intake is better idea tho
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Re: 408 stroker .. stock tpi air box?
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Re: 408 stroker .. stock tpi air box?
When yer engine is moving enuf air to feed those ci, you need 4"-5" AND high pressure area of the car, higher rpm=bigger inlet
#9
Supreme Member
Re: 408 stroker .. stock tpi air box?
https://www.thirdgen.org/forums/fabrication/768690-my-cold-air-intake.html
That he could bench flow his creation lends some credibility to the project. What I found really interesting is his statement that the air filters represented zero restriction. This contrary to what I've read from tech articles and K&N but who am I to argue with a flow bench.
Last edited by skinny z; 03-10-2020 at 10:43 AM.
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