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streeport increase engine loudness?

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Old 03-18-02 | 12:56 AM
  #1  
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From: Topeka, KS
streeport increase engine loudness?

right now my stock engine is way too loud to even drive hard around town. I have gotten one ticket already but it was luckily thrown out.

so after i streetport my engine is the loudness going to increase even more?? I am thinking it obviously is, so should I put more restriction on my exhaust system to quiet it down??

or should i say screw it and leave it loud because there are harleys and other cars louder than me that dont get pullled over?
Old 03-18-02 | 07:08 AM
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Try a quieter muffler. Also streetported engine will be louder since there is more inflow/outflow of air and exhaust.
Old 03-18-02 | 07:29 AM
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When I got my motor street ported, the sound did get louder using the same exhaust. Not only did it get louder, but it sounded 'nasty'. It had a distinctive crack to it that after about 5 min. felt like a drill going through your head. I wore earplugs for a while till I changed the exhaust a little. I think the extra sound comes from a larger exhaust port along with more intake noise from larger intake as well.

Anyhow, it does have a distinctive highpitch crack to it that was not there with the stock 13B.
Old 03-18-02 | 07:59 AM
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ARGH... lost the post.

It depends on how much earlier the exhaust port opens. When I did my SP I didn't touch exhaust port opening, and it wasn't louder than a stockport. Lost a bit of top-end, though, but top-end wasn't my concern. (why bother with top-end when you need a quiet exhaust and are running a stock carby?)
Old 03-18-02 | 11:28 PM
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My advice is to put a bumper sticker in back that says "hurleys are louder then my car" and hurley owners who don't use helmets eventually need a extra loud exhuast to just hear it! LOL When the cop sees that sticker, which you'll systematically place near the licence plate so Mr Cop will see it and think and give you a gentle warning instead. he he.. Or if you ever see a cop, just engage the clutch and idle by as quiet as possible. Open headers at idle isn't rediciouslly loud really..
Old 03-20-02 | 10:32 PM
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**** noise laws. Take the entire exhaust system off and peel out through town like a madman shooting flames and all. Harleys can only go fast when they ride in the back of pickup trucks. There are plenty of Honda boys out there with there fart pipes to keep most cops busy. Cops where I live don't care about noise laws but they are not cool about the whole spinning your tires and doing donut thing, I don't get it. WTF
Old 03-22-02 | 12:37 AM
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I had my street port done by TNR in queens and man was it loud i think they over did it i've recieved several tickets where i live and this is that i still haven't put my mid pipe on yet i'm telling you my car is really loud but it sounds mean as hell. what i do when i come across my town i just put the car in nuetral and let it cruise then you caný really here the exhuast but your right those ******* harleys are louder than our cars so why don't they get the freakin tickets hey WACKYROTORY thats not a bad idea....or just get a silencer for your exhust and but it on b4 you go back into your town. thats what i'm going to do when i get the midpipe just a thought
Old 03-27-02 | 02:15 AM
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yes it gets louder, much louder....my friends is streetported and mine is'nt, and it is a big difference.
Old 04-01-02 | 04:43 AM
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i know a stupid question but what do you guys mean by streetport
Old 04-01-02 | 04:45 AM
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Originally posted by ROTANG
i know a stupid question but what do you guys mean by streetport
It'd be called an extend port down under.
Old 04-01-02 | 05:12 AM
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thanx bro
Old 04-01-02 | 05:41 AM
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Actually the type of exaust port makes a big diffrence.. If the bottom of the port is pretty much flat it opens all at once and is very loud, if you round out the bottom of the port it will be much quiter because it opens a little slower...

Also you could do what I did and get a 3 1/2 in 3 1/2 out muffler and weld it in to the midpipe as a sub muffler prior to the actual muffler.. my car got much quiter and now has a sweet bass sound to it...
Old 04-02-02 | 12:08 PM
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When I get a Streetport done to my car, I'll stick a straight 3'' exhaust with no cat no remenence of a cat, nothing and just tig a 5zigen exhaust to it.

I'll be pulled over within an instant. Cops don't like me!
Get pulled over for not having a licence plate on the front of a car (had one on the back though!) but not for doing 180 on the QEW following a honda civic who though he was invincible..HA! Showed him!
Old 04-03-02 | 09:09 PM
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Add a turbo it acts like a 1/3 of a muffler.
Old 04-04-02 | 08:21 PM
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Wizzzzzzzzzzzzzzzzzzzzz PSSSHHHIIIIII!
Old 04-04-02 | 08:30 PM
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Originally posted by Dragon
Actually the type of exaust port makes a big diffrence.. If the bottom of the port is pretty much flat it opens all at once and is very loud, if you round out the bottom of the port it will be much quiter because it opens a little slower...
Or leave the exhaust opening point alone and only change exhaust closing. You get a quieter exhaust because it opens later like stock, but you still get a good pulse because of the flat edge. The added overlap is a good thing too
Old 04-04-02 | 08:45 PM
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Originally posted by peejay
Or leave the exhaust opening point alone and only change exhaust closing. You get a quieter exhaust because it opens later like stock, but you still get a good pulse because of the flat edge. The added overlap is a good thing too
Boy, I'd like to see this proven.

All the literature I've read up on overlap implies it's very tricky to get power gains due to the pumping/reversion tuning of the intake and exhaust tracts.&nbsp Are you claiming increase overlap in a 13B will automatically cause gains in mid-range even with the "stock" ports?



-Ted
Old 04-04-02 | 09:04 PM
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Something many people are overlooking is the fact that most porting jobs include removing the noise diffuser in the exhaust port.
This diffuser blends the exhaust crack a bit, mellowing the note considerably.

I went from a stock engine to a ported engine (no diffuser) on the same exhaust, and I noticed a definate increase in volume, though not bad at all.

With the ported engine and a Bonez race pipe -DAMN it sounded HORRIBLE!!! Weedwhacker extrordinaire!! Awful beyond belief.
I put a cat on just to make the sound normal.
I later put on a gutted cat- still sounded pretty bad, but not as bad as the bonez.

It wasn't untill I put the header on that DAMN it started getting really loud.

I now have a wrapped header, wrapped stainless Borla pre-silencer (xr-1), dual edelbrock ceramic RPM mufflers, and dual resonated Hooker Tips.

The wrapping of the header and pre-silencer really mellowed the note, since you could hear quite a bit THROUGH the piping!
Now, It sounds great, nice and mellow!!
Old 04-05-02 | 12:53 PM
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Originally posted by RETed

Boy, I'd like to see this proven.

All the literature I've read up on overlap implies it's very tricky to get power gains due to the pumping/reversion tuning of the intake and exhaust tracts.&nbsp Are you claiming increase overlap in a 13B will automatically cause gains in mid-range even with the "stock" ports?



-Ted
If you took a drive in my carb'ed 12A you would have thought it was an injected 13B from the way it would pull from any RPM in any gear.

If you leave a port mismatch between the intake manifold and port runner so that the engine's runner is larger than the manifold's, you will see minimal reversion in the intake tract because the flow will only want to go in one direction. This helps a lot!
Old 04-06-02 | 10:30 AM
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NA BP and turbo BP are two different things.



-Ted
Old 04-06-02 | 12:14 PM
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Who said anything about BP or turbo?
Old 04-16-02 | 11:22 AM
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is overlap though changing exhaust ports bad on a turbo motor? We opened the exhaust a lot and have lost all boost response under 4500 rpm. its a sad engine until 5500 rpm , not what i expected. Was this a bad port job??
Old 04-16-02 | 10:36 PM
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The solution to the noise is an Apex N1. When you're hanging out with the gf, keep the silencer in, on sundays going down the quarter, take it out.

Just hope no one tries to 'test' you when you have it in!

Anthony
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