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Hooker Side pipes. Any one had them decibel tested? (more pics added)

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69 DIRTY RAT:

--- Quote ---Originally posted by jdunne
What is done on the bike pipes is the use of a small pack of washers with gradually decreasing center diameters...one well known brand was super trapp....the harleys straight pipes are known to use a similar restriction system(particularly about rego/roadworthy time!).....the other trick that does help is to turn down the outlet on the pipes towards the ground.....those that have heard my small block at full bore(6800 rpm) on the track will know how loud it is,but surprisingly it passes the noise tests at 2500 rpm with the same system....it is very very unrestrictive at higher rpm and surprisingly quiet at lower rpm...john;35;35
--- End quote ---


can you decribe what you have done on yours then? Have you done this washer system on the Vette? Our db levels are measured at 3200 rpm are yours 2500rpm? and is it 95db in Vic?

jdunne:
When mine did the test it was static,45* from the pipe end at 1 metre.....it is supposed to be at half rpm....my tacho has orig redline at 5500...guess they allowed me some leeway as it should have been 2750....my system is custom long tube headers,Xpipe,and single magnaflow muffler on each side....the pipes are 2 1/2" duals,i deliberately got the mufflers with offset inlet/outlet rather than centerline inlet/outlet.....the tips are turned down(as they were in 74 anyway as standard)......i vaguely recollect the test as being 93 or 94db......RHD69 has more recent experience and his is with a bigblock...what ever it was the tester said i was well under the limit....i know at phillip island on the main straight they warned me that i was right on the limit which i think is 96db but that was measured at some distance from the edge of the track and i kept as far as i could to the other side of the track!!!! i was trying very hard in second and third gear so i was well over 6500 rpm.....sadly i was going far too fast to hear it but was told by those in the stand it sounded really good to hear a small block fairly bellowing up the straight....john;35;35

demonx:
The reason I was asking is I'm getting my 70 vert ready for a RWC and VASS inspection.

At the moment it has sh*tty/leaking header gaskets and other exhaust leaks underneath the car which they'll probably knock. On top of that it has no mufflers, only a pair of huge hot dogs and the car is louder than Hooker pipes as it sits.

I also have a set of Hooker headers and pipes sitting here, but I have no idea if they'll pass a RWC and VASS.

If the Hookers fail than its a big job to put all the other crap back on to get the ticket just to take it all off again after the ticket!!!!!

69 DIRTY RAT:
If you dont go the sidepipes to get it registered & get some good mufflersfor an underbody exhaust that would fix it!  Other Big Blocks I know make 95db @ 3000rpm so a SB should do it easy. Its just sidepipes are hard to get under control! Another method to quieten the sidepipes is to only connect 1 or 2 of the sidepipes and block the others ie 4 -1 pipes off engine then into 1-2 pipes of the sidepipe, but again I think that would decrease power!

demonx:
Heres a pic of the mufflers I got with them. They are stamped hooker.

As you can see, "Bubba" has welded them in and cut off the flanges. Didn't know that till after they arrived from interstate.

Either way, I have absolutely no idea what these mufflers are and how loud they would be.

Looking into them they seem to be just a 2" maybe 2 1/2" tube?

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