Smallport intake cut and shut...?

[JDMBenji]

Hello everyone,

My names Ben.

I have a few issues at the moment, I've broken my bigport engine. The keyway broke that the crank pulley sits on and it's wobeling all over the place which in turn caused my battery to run low and discontinue the circulation of water through my block...

So I bought a smallport engine off a mate for $100 =D. The only difficulty is the intake manifold everything else still looks like it is much the same but I'll find out how difficult it actually is soon enough.

But I was wondering if anyone on her had a cut and shut smallport manifold or knows how to do it? Would be able to lend me a hand.

PS - it's for an 86 that had the JDM bigport.

Has anyone heard of any cheap engine stands going as of late?

Cheers guys

[Nikkojoe]

You can try and get a T3 smallport to bigport adaptor plate to use your old bigport intake manifold (you dont run tvis as the adaptor goes in it's place).

Otherwise someone that can weld alloy can modify your intake. Try a few engine builders or fabrication places.

[timbo]

my advice is go for whats cheaper. i have a cut and shut manifold on my smallport and i've never had a problem with it, looks like a fairly good welding job. check out my members ride thread for a picture.

[Tim.duncan]

im also intrested in as much info as possible!

i am under the impressions that if you just hack the front and back off and weld them up it affects the way the oil breather set up works. now this is an issue with the smallports as they run a Manifold Air Pressure sensor for the ecu.

so do you need to cut threw the runners and turn the whole plenum around to avoid this???

can some one shed some light?

[Nikkojoe]

The Map port is not affected by the cut and shut. The oil breather is, so what i would do is get a fitting put onto the intake pipe (or get a rubber intake pipe with one) and run the breather to that port.

[Tim.duncan]

ahhh simple an easy, cheers mate dident think about that at all

[sun_moon]

please do not do this. smallport manifold is a FAR better design... there is a video on youtube showing when they cut the manifold at the runners, it shows how restricted they are compared to a smallport manifold.

the beauty of using a smallport engine is u have an engine with a DECENT port size and also u get a better manifold.

[timbo]

DO NOT run the oil breather into the intake pipe, ie before the throttle. i bought my car with this setup and the throttle and manifold were clogged with residue and gunk (plus the original bigport pipe now has a hole in it...). i highly recommend running a catch can to avoid cleaning your throttle every week!

[Nikkojoe]

Didn't say it was better, i said it's easier.... (assuming he already had a rwd bigport manifold - of which then he would probably have a rwd throttle body so he could run the oil breather to the intake without drama).

[Nikkojoe]

If you have seen a factory manifold this is how it's done. If your motor is in shit condition it's gonna push a lot of oil and shit into your intake having it hooked up like factory. I've never had a problem with this and this is how it's always been done for me.

I've seen a rebuilt engine where the cylinder bores were too big that it pushed oil into the intake at idle....