How much would changing my exhaust effect my tune?
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How much would changing my exhaust effect my tune?
So I am going to be running a BP 12A with a holley 650. I wanted to know if i am risking anything by tuning with my dumps open then using Smaller diameter exhaust for noise control on the street.
I am fine with just not having the all the power, but I wanted to make sure the added backpressure with the dumps closed wasnt going to cause any major issues or damage.
I am fine with just not having the all the power, but I wanted to make sure the added backpressure with the dumps closed wasnt going to cause any major issues or damage.
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So I am going to be running a BP 12A with a holley 650. I wanted to know if i am risking anything by tuning with my dumps open then using Smaller diameter exhaust for noise control on the street.
I am fine with just not having the all the power, but I wanted to make sure the added backpressure with the dumps closed wasnt going to cause any major issues or damage.
I am fine with just not having the all the power, but I wanted to make sure the added backpressure with the dumps closed wasnt going to cause any major issues or damage.
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It'll probably affect the tune a bit, but not enough to worry about. Like trochoid says, depending on how restrictive your exhaust is, it might adversely affect drivability because of the increased intake charge dilution.
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The plan was to have 2 dumps right after the header, then a collector down to 2" or 2.24" back to the muffler. If there is room I might add some short glass packs.
It will have a wideband. but I have a feeling with this setup I will need 2(one for each pipe before the dump)
It will have a wideband. but I have a feeling with this setup I will need 2(one for each pipe before the dump)
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if you tune it uncorked, it'll probably just be really rich corked up, but its impossible to say how much.
going from an open dump to 2" pipe is such a huge step though, it may not even run. you may have to have a "street" and a "race" jet setup
going from an open dump to 2" pipe is such a huge step though, it may not even run. you may have to have a "street" and a "race" jet setup
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If this was an injected motor I would be willing to run a dual tune, but other than that I am lazy.....
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EDIT: Its kind of a long story but I did not intend to have a BP. It just kinda fell in my lap so I am making due with what I have
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I'm not trying to discourage you, or be an ***.
Just stating my experience. I have a Monster Ported 12A in my Daily Driver. Originally it sported a RB Header/Presilencer and Stock 85' exhaust on back.(Tone sucked) And honestly, it was loud but just right for my taste. I do like a noticable but not annoying exhaust.
After, I tried porting a exhaust manifold to match my exhaust ports(they're huge, words can't describe) and then ran a open downpipe to the stock rear exhaust. Then it was quiet, to me. I then changed again to a Apexi N1 muffler. Loud, loud, loud. Even though I didn't change any tubing diameters.
After that I went to a flowmaster muffler, which was really quiet.(50 series) the thing was just too big. Flowed plenty though.
So, I then tried running the stock 81-82 connecting pipe and muffler with the ported manifold. A little louder, but, tone sucks. Like all stock exhaust does.
Nowww I have a custom fabbed 3.5" header with a scavenger style muffler welded in it and the stcok 81-82 rear exhaust. It's Hella loud. But, again, not too much for my taste but it does attract to much attention. Simply cause my 81-82 muffler is rusted out, has some holes in it.
So I bought a RB 'street port' muffler last night, we'll see how she sounds when I get her on. The tone is already amazing with my big header. Even with my POS muffler.
I'll have my custom header, 81-82 CP, and Street port muffler. IMO, it's a good combo for a big port engine daily driven that you want to make good power with and still be, somewhat quiet let's say. Or, tolerable would be a better word. It's all about a persons opinion. And another thing, at first everythings going to seem loud when you bolt it on but after driving it a while, it doesn't seem so bad.
Just stating my experience. I have a Monster Ported 12A in my Daily Driver. Originally it sported a RB Header/Presilencer and Stock 85' exhaust on back.(Tone sucked) And honestly, it was loud but just right for my taste. I do like a noticable but not annoying exhaust.
After, I tried porting a exhaust manifold to match my exhaust ports(they're huge, words can't describe) and then ran a open downpipe to the stock rear exhaust. Then it was quiet, to me. I then changed again to a Apexi N1 muffler. Loud, loud, loud. Even though I didn't change any tubing diameters.
After that I went to a flowmaster muffler, which was really quiet.(50 series) the thing was just too big. Flowed plenty though.
So, I then tried running the stock 81-82 connecting pipe and muffler with the ported manifold. A little louder, but, tone sucks. Like all stock exhaust does.
Nowww I have a custom fabbed 3.5" header with a scavenger style muffler welded in it and the stcok 81-82 rear exhaust. It's Hella loud. But, again, not too much for my taste but it does attract to much attention. Simply cause my 81-82 muffler is rusted out, has some holes in it.
So I bought a RB 'street port' muffler last night, we'll see how she sounds when I get her on. The tone is already amazing with my big header. Even with my POS muffler.
I'll have my custom header, 81-82 CP, and Street port muffler. IMO, it's a good combo for a big port engine daily driven that you want to make good power with and still be, somewhat quiet let's say. Or, tolerable would be a better word. It's all about a persons opinion. And another thing, at first everythings going to seem loud when you bolt it on but after driving it a while, it doesn't seem so bad.
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ive got a P port, and it was honda ricer loud when exhaust 2.0 went on it. the KEY for a big port engine is actually the intake, lots of noise comes out of that too.
i put a stock 12A air cleaner on, it only flows enough for like 6000rpms, but the neighbor doesn't complain that his head is going to explode.
exhaust 2.0 is similar to the RB street port system, except i used a pair of straight thru glasspacks (31" long!) and it goes from 2x2" pipe, to a 1x3" pipe to a borla, which is a bad choice.
the glasspacks lasted 9 laps, the borla survived just fine, but it doesn't sound all that great and its expensive and its not quiet. people in my 'hood have never experienced a car like peepers, and with all the stickers it's invisible too, so they act like its some kind of gardening accident
3.0 might just be 2x2" pipe to 1x3" to an RB muffler. airbox 2 is in the mockup stage, basically its going from the stock intake's 3" inlet to 6" to a duct that goes to the front of the car
i put a stock 12A air cleaner on, it only flows enough for like 6000rpms, but the neighbor doesn't complain that his head is going to explode.
exhaust 2.0 is similar to the RB street port system, except i used a pair of straight thru glasspacks (31" long!) and it goes from 2x2" pipe, to a 1x3" pipe to a borla, which is a bad choice.
the glasspacks lasted 9 laps, the borla survived just fine, but it doesn't sound all that great and its expensive and its not quiet. people in my 'hood have never experienced a car like peepers, and with all the stickers it's invisible too, so they act like its some kind of gardening accident
3.0 might just be 2x2" pipe to 1x3" to an RB muffler. airbox 2 is in the mockup stage, basically its going from the stock intake's 3" inlet to 6" to a duct that goes to the front of the car
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No worries, I wasn't taking it as you being an *** or anything. I really do respect the knowledge on this forum and am here to learn. Being a Mod on another fourm for a different car make I tend to be able to read people and what their intentions are.
I thank you all for the advise and will definitely be a learning process in building the exhaust for this car.
I thank you all for the advise and will definitely be a learning process in building the exhaust for this car.
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