Porting the intake manifold?

[stickgoat]

I tried to run a search on this, but only came up with one thread and it wasn't what I was looking for.

Has anyone done any porting of the intake manifold on the KA24DE? I know that porting is a reasonably popular mod with Probes, DSMs, and RX-7s, but I haven't seen too much about it regarding 240s.

Seeing as it's essentially a free method of gaining power it seems to me that it would indeed be worthwhile, but I've never had a chance to actually look at an IM off these engines, so I don't know what kind of gains can be expected.

Any insight would be appreciated.

[Exar-Kun]

by essentially free, I suppose you mean your going to be doing the porting by yourself...

its a good mod, and my 300ZX had ported manifolds(yes, there are two, an upper and lower)..and it felt like the engines power curve was smooth...I didnt dyno it though.

when you port the manifld, you have to know what your porting it TO, IE either the head(best method) or the gasket. porting it directly to the head usually requires the entire engine to be removed. I would also suggest you get it polished or extrude honed while you have it out, this will give you more HP than just porting allone.-chet

[GatorS14]

this weekend my brother port and polished his intake manifold and throttle body.It sounded alot better,when we took it off there was unbeleivable carbon buildup, he used a drimmel with some kind of diamond sander bit. he said he could feel a little difference.

i was wondering if anyone with a 240 has ever did theirs and how tough was it ?

[jrc90240sx]

I might try to clean it up alittle while i am rebuilding my engine, as i will have it off for about 2 weeks. But i wont be able to tell you if it makes any difrence as i will be doing it right off of a rebuilt engine.

[apzak]

Quote »this weekend my brother port and polished his intake manifold and throttle body.It sounded alot better,when we took it off there was unbeleivable carbon buildup, he used a drimmel with some kind of diamond sander bit. he said he could feel a little difference.[/quote]

Couldn't you get rid of carbon build up with those fuel additives they have on the market now? Restore or whatever it's called. I heard it works, but after a while the effect goes away as the carbon builds back up.

[Open4Cycle]

Exar-Kun, he asked about porting the intake and you are replying about match porting. Match porting is just one part of porting the intake tract. Stickgoat, I'm currently building/modifying a KA24E and the IM on it is rough cast on the inside. On this manifold there looks to room for performance gains but getting a burr or sanding drum inside the long primary tubes would be hard. Extrude hone looks the way to go for only smoothing and enlarging the runners.

[Aries]

extrude hone, or good work with a dremel flex.

[Powerbraker13]

Would sand blasting the inside of the intake maifold be similar to an extrude hone? If not, how would I extrude hone by myself?

[Exar-Kun]

you cant unless you have acess to a machine to do it.-chet

[Structure240sx]

Couldn't you get rid of carbon build up with those fuel additives they have on the market now? Restore or whatever it's called. I heard it works, but after a while the effect goes away as the carbon builds back up.

the fuel additives dont go through the intake manifold. they work inside the engine.

[I am Technoman]

I did a little "match porting" when I installed my HS header. I used a Dremmal and some Diamond tips. After I got the roughness off I used sand tips and cream to polish all the exhaust ports and of course I matched the header gaskets to the ports. I guess I got a little out of it maybe 4HP. I need to do the intake and intake ports some day. The best way in my opinion is the have it all ported and flow tested. Flow testing with extrude honing is the best kind of port job you can have done.

[Nismo_Freak]

You can use a little Seafoam in the intake.