hks silent hi power

[DeanS15]

hi all,

i've had a hks silent hi power fitted to the car along with a ths turbo pipe and downpipe and an apex s13 decat. basically im baffled as it seems to sound as though it is blowing although i havent any leaks in the system....everything was brand new and fitted with a genuine turbo elbow gasket and all gaskets had sealant applied too. can anyone help? as i dont know if this is how the s15 is meant to sound when you remove all the restrictions.....

only other thing is that the system centre box on the hks comes down stupidly low and is scraping occasionally, but performance has improved a lot since it was fitted.

 

[Nicely]

My system sits low, but not so low that I can't get over speed humps. etc. Occaisionally I'll get a small scrape, but I know when that might happen and take it very slow. And that's with the car dropped 25+mm.

You need to get someone with foot on accelerator while you work you way down the car finding where the leak appears to be coming from.

 

[JEZ 8553]

You possible may have knocked it and loosened a gasket. Ive got the same problem with my Trust PEII, the centre box sits very low. Im going to have to have agood look underneath and see if it will benefit from some shorter rubber hangers perhaps, maybe even another bracket to keep the box up higher ?

 

[DeanS15]

hi guys, just to recap there are no leaks in the system at all, this is why im baffled. as you said nicely it scrapes occasionally but if i half and half speed humps or go over ramps at an angle im ok. the sound is almost like its blowing, i just thought if you take away all the restriction altogether you may have a bit of a rough note from the exhaust anyway?

im thinking of getting it put on the rollers and have a little diagnosis done as power seems to be good, and the system isnt leaking so it shouldn't sound like this so maybe its due to something else as it sounds like it on idle too but the idle is fine and steady at about 850rpm.

im truly baffled......

 

[Pazz]

You didnt really need sealant + gasket. It matters soooo much what quality of sealant you use. As cheapo stuff just makes the situation worse. Just the gasket alone would of been fine.

If it was blowing it would probably sound tractor-like. But you seem adamant that it is not leaking.

 

[Nicely]

Its worth listening to the turbo gasket too...

 

[Auss15]

Its worth listening to the turbo gasket too...

I was going to suggest that as I have just replaced mine and its not uncommon on the SR20DET's. Mine had only done 55K

 

[DeanS15]

by turbo gasket nicely do you mean turbo to manifold or turbo to downpipe? i ask as the turbo to downpipe one was replaced with a genuine nissan item when the exhaust was swapped. unless there is a gasket that is integral to the turbo in which case i really hope it isnt that as it sounds expensive! im planning on uprating the manifold soon - if its still there after that then i dont know......

once again the fitter did mention that the turbo should be smoother when coming in, he said boost was good - power was good - there was no play in the turbo that he could feel and that it spooled nice and quick. i replaced the plugs as per his reccommendation and the flat spot is slightly better but still there - i think the thing causing the exhaust noise and the thing causing this flat spot are one and the same........

 

[Amused_15]

Dear Dean,

I share the same peculiarity. Im not running a HKS silent high power but if i may, id suggest inspecting your decat pipe if it has a TCV(torque control valve). Not too long back a mate of mine had the same problem but after permanently opening the valve it seemed ok but still feels as if the exhaust is blowing.

On mine i too am running a 3 inch cat replacement and find the same problem. My idle is steady and on the rollers there is no loss. My power delivery is smooth. However just to share, try getting her up above 180kph and tell me how your exhaust note sounds. Mine went silent...in fact is was a refined hum as i pushed 250kph and only the turbo and wind noise could be heard.

What do u think?

 

[gunner93]

Hi guys,

My zorst config is Tomei elbow//custom 3" down pipe c/w flexi pipe//Apexi N1 cat back. The sound vibrates the entire cabin & rear mirror at 4000rpm and higher. I'm still at stock height but the Apexi N1 centre box is just 4" off the ground. If I remove the centre box to gain ground clearance, will the sound gets louder? The centre box is a resonator no?

 

[DeanS15]

Dear Dean,

I share the same peculiarity. Im not running a HKS silent high power but if i may, id suggest inspecting your decat pipe if it has a TCV(torque control valve). Not too long back a mate of mine had the same problem but after permanently opening the valve it seemed ok but still feels as if the exhaust is blowing.

On mine i too am running a 3 inch cat replacement and find the same problem. My idle is steady and on the rollers there is no loss. My power delivery is smooth. However just to share, try getting her up above 180kph and tell me how your exhaust note sounds. Mine went silent...in fact is was a refined hum as i pushed 250kph and only the turbo and wind noise could be heard.

What do u think?

well the funny thing is my stock exhaust made the same type of noise at idle, as does my girlfriends and its a completely different car since having the hks fitted performance definitely seems to have improved over standard and the car doesnt feel down on power so guess this one will just continue to confuse me but its pretty easy to live with

gunnner 93, as for removing the centre box - i have done this before on another car and it will make it a lot louder - reason i went for the silent hi power (apart from the full stainless) is the fact that it wasnt too loud - something that my previous car was. thenovelty of a noisy exhaust - for me - soon wears thin

 

[Amused_15]

Ya it is but the tone changes noticably. it now growls deeper at lower revs.