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TDI Power Enhancements Archives on TDI Power Enhancement related items.

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Old October 14th, 1999, 06:26   #16
SkyPup
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Default Re: Techtonics Tuning Exhaust Install Pics

Ollie, the sound factor is virtually nil. It is very quiet, if you wanted to try to make it loud, you would have to remove the rear muffler and even then it would be not very loud.
As a matter of fact, the diesel engine and turbine are louder than the exhaust. At idle, you can not hear the exhaust at all. In mid range cruising, no exhaust note. At WOT maybe a little bit louder.
This is a totally unobtrusive system as is. I like it alot and it certainly reinforces my Wetted TDI engine no doubt.
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Old October 14th, 1999, 06:32   #17
SkyPup
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Default Re: Techtonics Tuning Exhaust Install Pics

Just to reinforce the benefits of the exhaust mods:

RULE #1 - Backpressure in a turbo exhaust system is evil.

RULE #2 - the best exhaust for a turbocharged TDI is the least exhaust.
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Old October 14th, 1999, 09:12   #18
SkyPup
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Default Re: Techtonics Tuning Exhaust Install Pics

It is a common misconception that the exhaust turbine half of a turbo is driven purely by the kinetic energy of the exhaust smacking into it (like holding a kid's tow pinwheel behind your tailpipe) While the kinetic energy of the exhaust flow does contribute to the work performed by the turbo, the vast majority of the energy transfered comes from a different source.

Keep in mind the relationship between heat, volume, and pressure when we talk about gasses. High heat, high pressure, and low volume are all high energy states, low heat, low pressure, and large volumes are low energy states.

So our exhaust pulse exits the cylinder at high temperature and high pressure. It gets merged with other exhaust pulses, and enters the turbine inlet - a very small space. At this point, we have very high pressure and very high heat, so our gas has a very high energy level.

As it passes through the diffuser and into the turbine housing, it moves from a small space into a large one. Accordingly, it expands, cools, slows down, and dumps all that energy - into the turbine that we've so cleverly positioned in the housing so that as the gas expands, it pushes against the turbine blades, causing it to rotate. Presto! We've just recovered some energy from the heat of the exhaust, that otherwise would have been lost.

This is a measureable effect: Stick an EGT upstream and downstream of the turbo, and you see a tremendous difference in temperature.

All else being equal, _The amount of work that can be done across an exhaust turbine is determined by the pressure differential at the inlet and outlet_ (in english, raise the turbo inlet pressure, lower the outlet pressure, or both, and you make more power) Pressure is heat, heat is pressure.

Raising the inlet pressure is possible, but tough. Lowering the outlet pressure is easy - just bolt on a bigger, free flowing exhaust. I've seen a couple of posts from people who added aftermarket exhausts, who report "my turbo spools up faster now" Well, that's because by lowering the outlet pressure, you increased the pressure differential, and now the exhaust gas can expand more, and do more work. That increased work pushes harder on your turbo, and it spools up faster. You should also see less boost drop at redline, because if an exhaust system is flow-limited, once you pass the flow limit of the system, any additional gasses you try and force through it only raise the outlet pressure. Higher outlet pressure, lower pressure differential, less work, less boost.

1) Turbos reclaim energy that would otherwise been dumped overboard in the form of heat, by using exhaust gasses to spin a turbine, which in turn spins a compressor, which compresses the intake air. 2) Compressed intake air makes more power, because it allows you to burn more fuel per power stroke of the engine, and because it helps scavenge the engine. (The new, compressed, intake charge "blows out" the remaining exhaust gasses) 3) The amount of work done by a turbo's turbine depends on the amount of gas flow through it, and the pressure differential across it. 4) You can improve the turbine pressure differential by installing an exhaust system with a higher flow capacity than stock. It's impossible to have "too much" exhaust flow downstram of the turbo. 5) The intake compressor works best when it has been specifically sized for an engine's flow requirements and boost levels. 6) The best way to choose a compressor wheel and housing is to call the manufacturer of the turbo, and answer all their questions. 7) Intercoolers are our friends. They reduce the temperature of the compressed intake charge after the compressor has heated it. 8) An intercooler is only as good as the air flow into it ***and out of it*** 9) Wastgates limit boost levels by acting as a "rev limiter" for the turbo.

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Old October 14th, 1999, 17:25   #19
tom
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Join Date: Sep 1999
Location: Tucson, Arizona, USA
Default Re: Techtonics Tuning Exhaust Install Pics

Questions concerning this installation Skypup:
How did you handle the size change 2" to 2.5" on the install from the cat. converter? Was there some modification required? (an adapter)?
Why as the system designed to handle so much air flow (644cfm)? I assume the original cat. converter portion of the muffler system isn't what was most restrictive, it was the muffler "choker" as shown in your photo.
I am interested in this companie's product and whould like to investigate getting one on my 98 Jetta.
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Old October 15th, 1999, 06:41   #20
SkyPup
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Default Re: Techtonics Tuning Exhaust Install Pics

Here is the scoop from Techtonics Tuning whom I spoke with last night (phone 503-843-2700 talk to Randy
Roth):

The A3 TDI's have a 50mm catalytic convertor.
The A4 TDI's have a 55mm catalytic convertor.

The A3 Jetta 2.5" cat back stainless steel unit is Part#252-450D and is $505.

They have A4 units for all A4 Golf, Jetta, and NB.

RULE #1 - Backpressure in a turbo exhaust system is evil.

RULE #2 - the best exhaust for a turbocharged TDI is the least exhaust.

Give them a call and ask them questions before you pay them, in my Jetta IV and NB there are NO PROBLEMS WITH THIS INSTALL. (PERIOD). REPEAT - NO PROBLEMS, ONLY SOLUTIONS!

------------------
99 JETTA TDI HERR WETTERAUER TORQUEMEISTER
98 KAFER WETT SPEKTAKULARE TURBOKOMPRESSOR
97 KTM 620 ADVENTURE RALLY PARIS-DAKAR SUPER THUMPER
ICH LEBE MEIN TECHORAD VW TDI'S MIT DIREKTEINSPRITZER TURBOKOMPRESSOR


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Old October 15th, 1999, 07:47   #21
Olli
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Join Date: Feb 1999
Default Re: Techtonics Tuning Exhaust Install Pics

SkyPup,

The clarity of the pictures that you have posted is incredible! What kind of camara did you use and how did you get the images posted? Once again, great pictures.

Olli
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Old October 20th, 1999, 09:41   #22
tom
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Location: Tucson, Arizona, USA
Default Re: Techtonics Tuning Exhaust Install Pics

I am researching the prospect of a muffler sysytem similar to Skypup's. Upon examination on the setup on my 98 jetta I notice the cat is not of the straight through variety. The pipe enters from the side and then exits the back (from then on it is straight to the muffler w/ dual tailpipes. A local shop can do about anything with good quality. Does the attached site link carry the Borla muffler you purchased? If so I can put a system together:
http://www.carparts.com/parts/search...link=38358|0|0

Will the lack of a straight path doom any improvement in this muffler system (even with a full flow add-on?
As was mentioned in a previous post, I am not going to mess with the cat. converter.
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Old October 20th, 1999, 11:35   #23
SkyPup
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Default Re: Techtonics Tuning Exhaust Install Pics

Any straight thru Borla muffler would be more than adequate for max flow improvement. The Borla on my TT system was the top of the line Borla patented XR-1 stainless steel racing straight through system with certified cfm of 644 for use on V-8 motors up to 450 HP.

Scope it out:

www.borla.com
{fixed url}

[This message has been edited by VW Derf (edited October 20, 1999).]
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Old October 20th, 1999, 12:14   #24
SkyPup
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Default Re: Techtonics Tuning Exhaust Install Pics

BTW, a straight thru 2.5" diameter pipe flows about 640 cfm, way more than any TDI would produce under any circumstances.
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Old October 21st, 1999, 05:24   #25
SkyPup
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Default Re: Techtonics Tuning Exhaust Install Pics

Installed the same excellent full flow exhaust system from TT last night on the New Beetle TDI, what a difference, the TDI and hyper hopped-up turbo really breathe strong now. Second and third gears are killer. The front end raises so high on WOT that you'd think the little BUG is jumping off the ground, plus the front wheel torque steer is quite significant in the lower gears, time for some bigger rubber and some first class Bilsteins. The full flow exhaust accenuates the turbocharger boost and the Wetterauer chip perfectly. Car is ultrasmooth throughout the entire rev range and very much improved on the top end too.
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Old October 21st, 1999, 11:17   #26
SkyPup
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Default Re: Techtonics Tuning Exhaust Install Pics

Some info on the Borla muffler that TT supplies with their excellent cat-back system. BTW, other "cat-back VW TDI" exhaust systems I inquired about prior to ordering the TT system were no "cat-back", they were simply different mufflers, some for more than what I paid for the real thing from TT!!!

XR-1 Raceline

Stainless Steel Racing Exhaust Products

"World's Fastest Mufflers"

Unique Features:

Uninterrupted highest flow straight-through patented design has been tested to actually out flow a straight piece of pipe!
Designed to meet the strictest noise requirements.
Made in the USA of 100% Aircraft-Quality T-304 Stainless Steel. It will never rust and is lighter and more durable than mild steel.
All welded construction, one-piece assembly maintains product integrity even under the most adverse conditions. Non-adjustable. No disks to remove or fall
off on the track.
Maintenance-free stainless steel sound-absorbing material to protect against burnout.
The best balance of sound and power on the market.

BORLA exhaust is built of aircraft-quality T-304 stainless steel -- stainless inside and out, not mild steel, not aluminum, not coated aluminum, not just
wrapped with stainless on the outside for show. Coating techniques, such as aluminizing, can somewhat prolong the life of mild steel, but coatings
suffer at the weld points. And, comparing aluminized steel to T-304 stainless steel is like comparing gold-plated metal to solid gold! T-304 stainless
steel has the highest chromium content, making it the most resistant to corrosion and therefore the most desirable material for a long-lasting exhaust
system. Note: Only the flanges are not stainless. In our twenty-year experience, we have found the 3/8"--1/2" flanges are so thick they will never affect
the performance or longevity of the system.

Late model cars and trucks are computer controlled to such an extent that it may take a
period of time (600-800 miles) before the computer reprograms to reflect the improved flow
characteristics of your new BORLA exhaust system.

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Old October 21st, 1999, 15:16   #27
Craig
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Join Date: Apr 1999
Location: Kitchener, Ont., Canada
Default Re: Techtonics Tuning Exhaust Install Pics

Now if they would only make some sexy-looking tips for those things instead of a bland single pipe. Ughh! Then I might just be interested. I like the Bastuck exhaust imported by H-S Motorsports. They offer 5 different tips styles. One for every taste.
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Old October 24th, 1999, 09:22   #28
**DONOTDELETE**
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Join Date: Dec 1969
Default Re: Techtonics Tuning Exhaust Install Pics

Quality Question:

There's a "custom exhaust" shop down the road from me. They're in a very small town near a larger city. I'm not sure what they sell 'cause I haven't stopped in yet. Do you think they can make an exhaust that's incompliance with rules #1 and #2 at a fair price? I don't know if they have stainless steel. But I'm not sure I need it here in the desert. Comments?

BTW, I don't recall if you answered the question regarding how you made the taper from the 2" cat to the 2.5" muffler. Can you paraphrase or recap, please?

Thanks,



------------------
Scott, KE4WMF
98 Jetta TDI w/50,000 mi
53 mpg (US) w/AC

http://members.aol.com/StealthTDI <recently moved to this new site>
(Features TDI Articles and Sound Files)

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Old October 25th, 1999, 12:05   #29
SkyPup
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Default Re: Techtonics Tuning Exhaust Install Pics

A normal muffler shop is NOT going to have mandrel equipment to create full 2.5" interior diameter, instead, where ever they bend it will be cramped with lots of wavy lines in the steel tubing. DO NOT try to save bucks getting a cheap system, it is simply not worth it. If you are going to change out to a new system, get the full cat-back mandrel bent system, not some cheap imitation. You can get it in aluminized steel if you drive in a non-winter salted area, otherwise, stainless steel will last longer than your car will.
BTW, as an aside, after installing the TT system on both my TDI's, Jetta & NB, I must comment on the outstanding undercoat job VW puts on these cars, it is much more comprehensive than any GM, Ford, or Chrysler undercoating I have ever seen, no wonder they warrant the body for so long. Of course if the body rusts through and you have the Wett chip or an aftermarket exhaust system, they can simply deny your warranty claims as the Wett chip or aftermarket exhaust would be responsible for the premature rust through! (Sarcastic!)
The A3 TDI has a 50mm cat while the A4 has a 55mm cat. The 2.5" diameter on the A4 TDI in both my rides comes all the way through the cat back to the center sub-frame where there is a connector on the OEM unit as seen in my photos. The OEM from there back is all one piece and all 2.0" interior diameter, the TT system I installed replaces all that with 2.5" straigh through. The mandrel bent pipes are TOTALLY smooth inside and out, no obstructions.
Go back to my photos and look at the second photo with the giant fat cat in the foreground, look back from there at the connector prior to the center sub frame - it is all one diameter all the way through.
Now look at photo #3, this is the connector I am talking about -> see it is all one size!

[This message has been edited by SkyPup (edited October 25, 1999).]
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Old January 18th, 2000, 07:05   #30
SkyPup
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Default Re: Techtonics Tuning Exhaust Install Pics

Tirzo, these are the photos you have been looking for, hope you see them now!
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