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stock intake mani

so i was wondering how much power can we make with the stock intake mani? what can we do to them to make them better? sorry if i use the wrong words right now but is extrude and hone a good option? who does it?
 

4thStroke

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People are making good power with the stock manifold. It keeps the powerband lower than what a SMIM will do. There is power to be gained up top with a SMIM.

The extrude honed stock manifold is good. FFWD Connection does the job. click

Brianawd went 11.1 at 131 with an extrude hone stock manifold. He has since went to a Hogan SMIM but he hasnt been back to the track since.
 
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belize1334

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I think it's pretty safe to say that unless you've already made extensive modifications to your powerplant (turbo, intercooler, fuel, cams, etc), you're money is better spent elsewhere. With the exception of the cyclone manifold which came standard with many JDM engines, anything other than OEM is gonna cost too much with too few gains to be worth your time and money.
 

well my car is non turbo and i staying that way. i want to get as much air flow as i can. with this mani i do plan on a build head ported with oversized valves. so would this be good with an extrude and honed mani?
 

belize1334

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Getting power out of a non-turbo is more complicated that with a turbo. Bigger isn't always better. Unfortunately there's not much of a knowledge base for n/a 4g63 power since you can do it cheaper and more easily with a turbo. I'd do a lot of careful research before I started to spend much money but I'm guessing that the intake manifold will not be the limiting factor for some time yet; exhaust headers, cams, etc will probably be more significant.
 

headers intake pipe are done i would do cams but if i do to big i will loose the low end i want thats why once i build the head i plan on doing this manifold. i really just want to see how much power i can put don before i turbo it. no one has done it so i though i would just go all out and do it. i have also added more fuel wit ha turbo fuel pump and 390cc injectors. next will be safc and air fuel guage.
 

belize1334

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Well in that case I'd try doing cams in combination with a cyclone manifold. The cyclone does nothing up top but increases torque the low RPM range. That might offset the low rpm losses of cams and allow you to get a little more up top. You can get one extrude honed if you want to increase flow but I think that SMIM manifolds might be a detriment to a non-turbo engine. You should probably also get a different MAF since the 1G MAF is pretty restrictive.
 
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4thStroke

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I 2nd the "stay away from SMIM on the non-turbo" notion. More CFM doesnt always means its going to make more power. You need to keep the velocity up, a larger plenum and runners will not help that. Much like porting a head, if you hog it out too much, you can make less power. Some people port heads by making ports smaller and reshaping them to make power, but thats a different subject so Ill leave it at that.

Usually, people hold off till the end of their build to throw a SMIM at the car. I just bought one and still went with the street version JMF for the sake of not pushing spool as late as the larger plenum ones.
 
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