Ported cylinder head equals noisy intake runners?

[jimtash]

The intake runners on the V-6 seem to make this hollow noise that gets a little annoying and I'm guessing it's because of the increased airflow in the cylinder heads due to porting. The runners haven't been matched to the intake and since I've got a spare intake laying around, I'm contemplating matching it to the intake ports. Would that offer a solution or at least tone down the noise a little? Any other suggestions? The noise itself is coming where the intake meets the heads right above the valley and all the runners are doing it.

To give you guys an idea of the air flow, the thing literally sucked a K&N filter clean. There was a big white spot where the MAF sits over that was as dry as could be. Thinking of going back to a paper filter because of it.

 

[SASHO91]

I dont have much experience with SHO ported heads, but with others you can pick up alittle extra valve noise. But if you are pinpointing it right at the cylinder head-intake manifold mating area, that could be a number of things.

And that is normal for that filter, even moreso for one that was over oiled. Go back to an paper element, keep your maf happy and your engine cleaner.

 

[ShadetreeSHOguy]

I'm with stupid on the aircleaner.

The K&N lets too much trash through and your engine wont like that in the long run.

 

[jimtash]

I dont have much experience with SHO ported heads, but with others you can pick up alittle extra valve noise. But if you are pinpointing it right at the cylinder head-intake manifold mating area, that could be a number of things.

And that is normal for that filter, even moreso for one that was over oiled. Go back to an paper element, keep your maf happy and your engine cleaner.

Yep, it's above the valley right where the intake and cylinder heads meet. Loosened both pulleys and ran the engine thinking it was a rotational noise in one of the accessories but it isn't.

 

[SASHO91]

I would suspect one or two out of spec shims.....

 

[jimtash]

I would suspect one or two out of spec shims.....

The engine only has roughly 1000 miles on it. The valves are shimmed within spec.

 

[SeanMc]

Mine has a little bit of a tick coming from the drivers side that you can hear when next to a wall. It's been doing this now for 98.4k miles, so I'm not to worried about it.

 

[somedude_001]

are you sure you don't have a air leak coming from one of your fuel injectors. maybe that is causing a whistling noise? If you intake is not port matched it is possible that the air is rushing against a sharp corner on the gasket or head and making a whistle. I would think that is pretty unlikely though.

what kind of noise are you hearing. I don't understand what a hollow noise means. Are you referring to the noise it makes at full throttle or at idle or cruising around.

 

[victorymike18]

Is the hollow sound similar to this video: http://www.youtube.com/watch?v=97R20R78vbI

It's certainly possible that the noise could be caused by a ridge in the intake from non-matched transitions, but how does the engine run? Any signs of a vacuum leak?

 

[jimtash]

The engine ran great until one of the bearings suffered from oil starvation. Working on putting a 3.2L block in it with the ported 3.0L heads. What I'll end up doing now is port match it to the intake and see if that resolves the issue.

Thinking it was harmonics in the mis-matched intake and head ports that caused the noise.

 

[AREA 91]

I have done several sets of ported v6 SHO heads and have never had a problem.

It's not the port job. Look elsewhere.

 

[yamahaSHO]

I have done several sets of ported v6 SHO heads and have never had a problem.

It's not the port job. Look elsewhere.

This.