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Engine Specific Info and Questions => IDI Engine => Topic started by: veector on January 13, 2010, 07:27:28 am
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I purchased and installed a giles superpump on my aaz along with a boost controller to get that k14 spinning 18-20lbs on full throttle. Now i've still got the stock exhaust which was put in recently by the previous owner. Downpipe, resonator mid muffler and end muffler. That seems like alot holding back that exhaust pressure... Would i benefit from deleting a few mufflers or would i need something else?
Thanks,
Vic
(http://img.photobucket.com/albums/v378/punkerboarder/IMG_1589.jpg)
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Turbo, resonator, mid muffler and end muffler!? holy cow :P The turbo itself acts as a huge restriction.
I think if you were to 2.25-2.5" turbo back and just have an end muffler, you would notice a giant increase in performance.
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Yeah, even just the weight of the stock exhaust system is a limitation in itself - the "suitcase" resonator under the back seat is pretty heavy and absolutely unnecessary.
I put a Magnaflow cat-back on my gasser, it worked great. It was a 2.25" though, so I left it on the car when I sold it. Noticeable difference on the gasser, so I'd imagine the diesel would like it even better!
Does your car not have a cat on it?
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If you still have the cat then loosen off the 3 bolts so there is a huge leak there and take it for a spin an see if there is any difference. You should locktight the nuts on so they don't fall off and cause your exhaust to fall.
You'll get the bottom of your car sooty and dirty though.
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No cat on my car so i think im going to have a straight pipe made from the downpipe and exit in front of the back wheel. Would i be killing my back pressure by doing that? Most likely il have something fabbed up with just one end muffler
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No back pressure is required since you have a turbo.
Look into upgrading the downpipe (custom) too if the pocket allows.
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Heh goes to show how much i know so i could run a straight pipe :)
I've got a good exhaust guy who im sure could fab up a custom downpipe. What would be a decent size? 2 1/2, 2 3/4?
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Heh goes to show how much i know so i could run a straight pipe :)
I've got a good exhaust guy who im sure could fab up a custom downpipe. What would be a decent size? 2 1/2, 2 3/4?
With 20lbs of boost, I'd go at least 2.5".. more likely 3" from the turbo the whole way back :)
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Back pressure is nessary on gassers but not Diesels. The better the Diesel breaths, the better she runs.
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awesome great info guys im sorta new to the diesel world. Il be looking into a 3" dp then :)
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Just spoke to my exhaust guy and he'll be fabbing up a 3" downpipe with flex hose, along with a side exit by the back wheel. Straight through :D Very good pricing too if anyone is looking for an exhaust guy in the west end of Toronto
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i made mine myself, only cost me 40 pounds for the piping
(http://i46.photobucket.com/albums/f124/shabber/17012010154.jpg)
i couldn't believe how thin the original down pipe was on mine
standard
(http://i46.photobucket.com/albums/f124/shabber/03012010114.jpg)
after
(http://i46.photobucket.com/albums/f124/shabber/17012010152.jpg)
3" all the way, made a massive difference and makes a great noise when you let off the throttle ;D
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i made mine myself, only cost me 40 pounds for the piping
(http://i46.photobucket.com/albums/f124/shabber/17012010154.jpg)
i couldn't believe how thin the original down pipe was on mine
standard
(http://i46.photobucket.com/albums/f124/shabber/03012010114.jpg)
after
(http://i46.photobucket.com/albums/f124/shabber/17012010152.jpg)
3" all the way, made a massive difference and makes a great noise when you let off the throttle ;D
if that thing ^ was on a n/a, you would not have hearing after driving 5 miles. n/a diesels are the LOUDEST thing i have EVER heard in my life.
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well it sounds nice on a turbo ;D
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Back pressure is nessary on gassers but not Diesels. The better the Diesel breaths, the better she runs.
But does that apply to non turbo's ?
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Back pressure is nessary on gassers but not Diesels. The better the Diesel breaths, the better she runs.
But does that apply to non turbo's ?
Yes sir! the fact that diesels do not need back pressure and gassers do, is soley based on the fact that gas engines have valve overlap because of cam design. because of the tight tolerances of these diesels there is no overlap.. therefore no need for back pressure.
Obviously it would be impossible to have 0 back pressure on a normal car unless you are running just the manifold.. but the less there is on a diesel the better. A turbo diesel will have just as much backpressure straight piped.. as an N/a would have with a single normal muffler on it.
either way it is probably 12% of what was there stock :) rip that old exhaust off.. 2.5" and a Turbo muffler outback! will be very UN restrictive. :)
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I have 3 inch SS at home waiting to be made up. Its gonna be much better.
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Back pressure isn't the deal, it's velocity that you want so the outgoing gasses sorta suck the incoming air into the cylinder right before the ex valve closes. No good unless you have some valve overlap.
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rabbitman you just described Back-Pressure with different words. lol ;)
I concur :)
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diesels dont need pack pressure. its just making the exhaust leave the engine a little harder. we already have 24:1 compression, we dont need back pressure too...
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What's the best exhaust I can put on my 92 1.6l n/a ?
I have an all stock system and want her to breath better!
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I remember reading somewhere that 8v gasser manifolds fit but not sure about the advantage
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3" straight pipe is the best exhaust to run on your 1.6 td. no muffler, no restrictions.
as for the gasser intake manifold, it fits, but it takes a bit more than bolting it on to get it to fit.you have to have a low mounted turbo, so it sits closer to the block and axle. otherwise the gasser manifold hits the turbo.
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2.25 OR 2.5 Diameter
I would go S/S up there..
techtonicstuning.com
Gee-Bee
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2.25 OR 2.5 Diameter
I would go S/S up there..
techtonicstuning.com
Gee-Bee
techtonics is expensive...
a local exhaust shop could do just as good of a job, for probably half the price.
and hes gonna make a 3" down pipe, so why go 2.5 after the 3" DP? thats just stupid...
and the fact that he was asking for the best performing exhaust for a diesel vw. techtonics exhaust systems work alright, but they dont make a 3" system, and i dont they sell an exhaust system without a muffler. and he probably doesnt wanna spend his left nut on an exhaust system. he has a turbo, thats enough muffler.
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They will build it with or without a muffler
I paid 315.00 for s/s 2.5 DP
300.00 for 2.5 Complete exhaust
Is that expensive ?
Mine's perfect,like everything else I do....
You get what you pay for ....
I do agree 3' would be nice but I think I would have a little clearance issue on my caddy
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615 bucks is expensive for a single pipe exhaust, yes. i personally would never spend that much for exhaust on ANY vw, not even a BRAND NEW one...
my buddy had a custom full dual exhaust put on his V8 s-10 for under 250 bucks. and that was with the cost of the flowmasters and everything. and the guy that did it, did a damn good job doing it. it wasnt stainless tho, but most people dont care if its stainless or not.
and that sounds a little snobby/egotistical saying that EVERYTHING you do is perfect..
there is no such thing as perfect, so go figure. there are only people who think "perfect" exists.
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the TT option is indeed a pricy one as the exhaust guy quoted me less than half of that for about the same thing. Im just saving up a bit of cash and the car will be dropped of for some work sooon
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Veector
I am running the same setup as you are but I am running at 15 psi of boost. Do you have an intercooler on yours or an egt gauge when running at 18-20 psi?
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So you wouldn't buy A full Ti exhaust if you had the money ?
I don't have time to make my own, I would rather pay a professional to get what I want, I was very happy with techtonics.
I sent them three different turbos and manifolds so they would have the pattern for others
I think some exhaust systems are a work of art.
Some exhaust systems for the Turbo 997 Porsche are over 6K without headers or Tip's
I mfg a strap seal for different exhaust mfg's for the muffler straps.
GB
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No egt or intercooler yet, hard to do work when you dont have a garage and its -5 outside. I usually keep it under 15lbs with small spurts to 17 or 18. Intercooler and egt gauge coming when it warms up!
GB- I would definitely buy one if the pocket allowed, being a broke ass student thought doesnt seem like it will for a few more years
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No egt or intercooler yet, hard to do work when you dont have a garage and its -5 outside. I usually keep it under 15lbs with small spurts to 17 or 18. Intercooler and egt gauge coming when it warms up!
GB- I would definitely buy one if the pocket allowed, being a broke ass student thought doesnt seem like it will for a few more years
GB doesnt understand the whole "using your money for more important things" kinda life style. appearently he has more money than he knows what to do with. and everything he does is perfect, just ask him. hahaha.
i hear ya tho, gotta save the money to keep the car running, not to put TT exhaust on it.
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guys, regardless of valve overlap and a need (or lack of need) for back pressure, you can have too big an exhaust.
It is said that if you go too big, the exhaust gasses expand too quickly, cool off, and slow down, thereby creating the very same back pressure you're trying to eliminate.
mm
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im thinking of doing a 3'' strait pipe with cherry bomb glasspack, do you guys think id have a problem passing inspection tho"?
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What's the best exhaust I can put on my 92 1.6l n/a ?
I have an all stock system and want her to breath better!
"Best" is highly subjective. On my 1.9NA I use a 8v GTI 4:2:1 stock header. I had to add a spacer though because the 1.9 is a bit taller then a 1.6. It will bolt on a 1.6. What you can also do is hollow out the bottom of the "toilet bowl" and increase it's diameter up to 2" or 2.25". I wouldn't go bigger then that on a NA. If you do some searching I think you will find what you need.