WTB: extrude and honed intake manifold

[e30slidewayz]

Just installed a performance head. Now I'm looking to increase the amount of air going in.

[Flash]

You want a bigger camshaft, bigger valves, and bigger throttle body for that!

[e30slidewayz]

got um.. well, new throttle body is on the way. just want to open everything up so she can breathe better

[castros]

What are you looking to spend?

[e30slidewayz]

Less than the $700 it takes to have it done lol. IE has then for $700 plus the core charge. There is a place that does it about 100 miles from where I live but it run $650. But I've seen used ones go for around $400.

[e30slidewayz]

And what would be a good intake boot to use? I'll be running either a 2.7" or 3" miller MAF with a larger throttle body. I've heard of people using e36 intake boots, but it doesn't look like the ports for the ICV and vaccuum lines are in the same spot.

[AnimalE30]

They aren't. The m20 has a port for the icv and a small vacume for the booster (depending on year irrc). The valve cover breather goes directly into the throttle body. The e36 has two ports on the bottom, one for icv and one for the valve cover breather.

It would probably be too much work haha. Love the idea of where you're going tho, how much power are you expecting when you're done?

[e30slidewayz]

I don't know, more hopefully lol. I've heard of 15hp gains. Won't really know til I get my full setup and get it tuned.

[Flash]

You will probably see maybe 1-2 HP tops, unless you plan on going forced induction. Lots of info regarding the boundary layer on the intake runners out there, worth a read or two.

[e30slidewayz]

Well if that's all I can expect, I may just take a dremel and match the intake manifold to the head for better flow. Now if I can just find an intake boot that isn't as restrictive.

[nando]

You will probably see maybe 1-2 HP tops, unless you plan on going forced induction. Lots of info regarding the boundary layer on the intake runners out there, worth a read or two.

not neccesarily true.

[nando]

Well if that's all I can expect, I may just take a dremel and match the intake manifold to the head for better flow. Now if I can just find an intake boot that isn't as restrictive.

this will do nothing. been there, done that. the entire length of the runner needs machined, and you can't do it with a dremel.

[e30slidewayz]

Then what's the point of porting, polishing, and gasket matching the intake ports on the head if the intake manifold isn't sucking in more air than stock?

[nando]

I'm not saying that. I'm saying you can't do much with a dremel. you can port match it but you can only reach about 2" of the total runner length. on the dyno it made zero difference.

also, boundary layers make little/no difference on the intake manifold because the injector is all the way at the end of the port.

[bmwstudent]

I picked up one of these from another member on here. Also purchased a bored throttle body from him too. I've recently purchased a myster-e head with the 274 cam. I will be freshening my engine up this summer (new rings and bearings), and will be installing the head first with the stock manifold. After i get it running and everything is good with it i'll be installing the manifold and the throttle body. I'll let you know what type of gains you can expect. I should be able to get it to a chassis dyne at my local dragstrip and actually post some numbers. Sorry not willing to sell it, just wanted to let you know i'll be posting something midsummer about it.