oregano

iTrader: (1)

i wanted to modify my intake manifold once my car is street worthy. i was wondering what sorts of things could be done to the stock manifold without porting the engine. id like to hear what others have done in the past.

also, dont u hate how on the n/a, the air goes in an 'S' shape before it enters the engine? i was thinking of maybe somehow changing the way the intake manifold is mounted so the the air has a straighter path to follow.

Rxmfn7

iTrader: (4)

Intake runner length has a profound impact on the power curve on the engine. The runners are set at that length to provide a balance of low to high end power. Just changing the manifold so the air has a "straighter path" will drastically change the way the engine behaves. You may pick up some high end power with a short and straight manifold, at the cost of all the low end and mid-range.

Basically mazda designed the intake runners at a set length for the port size and output of the engine. Unless you have a large port of some kind, or realy understand manifold tuning, dont mess with them.

That being said, the stock manifolds have some internal imperfections, casting lines, etc. You can dremmel them out , and port-match where the manifolds meet...but thats about it.

oregano

iTrader: (1)

hmmmm... i am going for high rpm power only. anything that will boost power after 5500 rpm is good.

maxrotor

are you going to port the engine?

oregano

iTrader: (1)

no, the cost of porting or rebuilding the engine does not seem worth it to me. i would rather wait till this ngine dies and buy a turbo motor.

i just wanna do as much as possible for free.

ShadowX

You're likely to get more power out of porting then you ever could with changing the manifold.

oregano

iTrader: (1)

i would love to port my engine, but this would require disassembly of the engine, which would require me to buy a $1000 rebuild kit to put it back together. also, the engine has 90k miles on it, so i would rather not invest in it right now, incase it dies on me.

maybe if i fall in love with n/a motors, i will build one in the future.

anyways, i guess noone has modded their stock manifold, which i guess shows it is not worth the trouble.

thanks for ur time guys.

Amur_

Next time check the archive, dumbass.


https://www.rx7club.com/showthread.p...threadid=79511