My Myth Busting Experiment--Please Comment!

IndigoBlueWagon

TDIClub Enthusiast, Principal IDParts, Vendor , w/
Joined
Aug 16, 2004
Location
South of Boston
TDI
'97 Passat, '99.5 Golf, '02 Jetta Wagon, '15 GSW
I've been debating about going to RC4 with my '02 wagon but continue to hesitate. Right now it's running RC3 with PP520s, a lift pump, Oldman intake, TyrolSport SMIC, and a 2.5" exhaust from the CAT back. I've been very happy with the car's performance, but as mod-addicts know, we always want more. However, there are several things I'd like to try before going the VNT-17 RC4 route. There's another thread here asking about CAIs, and I still wonder if a moderately modified TDI can benefit from more air. So here's my plan.

I understand DentSport, a performance shop about 40 minutes from me, has purchased a dyno. I am considering getting a baseline dyno (my car dyno'd at 135 HP and 260 lb/ft. last year in Baltimore, but I need a consistent piece of equipment and operator to make comparisons) and making the following changes.

- GHL downpipe install with a 2.5 inch exhaust, no CAT, and two 'cherry bombs' to manage noise
- DG race pipe or gutted EGR
- CCV mod
- R32 DSG airbox and snorkel (if I can locate one) with a larger MAF holder and intake line and something smoother than the 'dryer hose' that currently goes to the intake.
- PD150 intake or reasonable facsimilie

We all know that the way to more power is more fuel. But if you put in more fuel you need more air to clean up the smoke. A larger turbo will give you more air, but perhaps allowing the VNT-15 at 18.5 PSI better intake and exhaust will increase its flow as well, allowing me to increase fueling. After these steps I can then add an 11mm pump. And if that gives me a big boost in torque I may then add a cam to increase HP.

After getting a baseline, I could probably dyno (a) with the new exhaust (b) with the intake changes, and (c) with the pump changes. Jeff R. tells me the larger MAF holder and hose may require some chip re-tuning as the air will be flowing slower past the MAF. I could get that done before the post-intake dyno.

I've been thinking about this and talking to people about it for a while, but I welcome comments if you have direct experience or data on similar efforts. Opinions only or speculation is less helpful.

I may get the exhaust done this weekend as I already have the downpipe.
 

NathanMSL

Veteran Member
Joined
Sep 3, 2005
Location
Alvin, Texas
TDI
Golf, 2005, PD100, white
The exhaust will definately help. I made 18lbs of torque with my 3" system. The better you get the air in and the exhaust out the better the power. Let us know how it turns out.
 

IndigoBlueWagon

TDIClub Enthusiast, Principal IDParts, Vendor , w/
Joined
Aug 16, 2004
Location
South of Boston
TDI
'97 Passat, '99.5 Golf, '02 Jetta Wagon, '15 GSW
Will do. I've been following your thread with interest and admiring the handiwork on the exhaust.
 

n1das

TDIClub Enthusiast, Veteran Member
Joined
Jun 11, 2002
Location
Nashua, NH, USA
TDI
2014 BMW 535xd ///M-Sport, 2012 BMW X5 Xdrive35d, former 3x TDI owner
robert5995 said:
Indigo - Replace lower IC piping.
YES! Get rid of the "kink" in the stock lower IC plumbing. Every time I looked at the stock lower IC pipe in my 02 Golf I thought about how suspiciously restrictive it looks. It reminds me of the flat crevice tool attachment that goes on the end of a vacuum cleaner hose. The lower IC pipe basically flattens out without getting significantly wider than the round ends of the pipe. I suspect the flat part has a lot less cross-sectional area than the round ends of the pipe, creating a restriction.

I have KERMA's FMIC kit in my 02Golf and love it. Worth all the royal PITA it was to install. The lower FMIC piping got rid of the stock lower IC pipe. My 02 golf dynoed at 139 HP and 262 ft*lbs (not lbs/ft) at the wheels at New England Dyno Day V in October. There was no heatsoak at all with the FMIC. The plots from the 3 dyno runs were all right on top of each other. Smoke output is also reduced somewhat and I did the comparison before and after the FMIC with LSD fuel prior to switching to ULSD. Smoke is virtually gone with ULSD now.

I'm also on the fence about upgrading to a VNT-17 and RC4. One reason why I haven't pursued it is the cost...mods are expensive! I don't have the money to keep throwing at mods right now. If and when I someday have to replace my VNT-15, that's when a VNT-17 goes in as a replacement.

Also, what clutch do you have in the 02 JWagen?
 
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robert5995

Veteran Member
Joined
Apr 8, 2006
Location
Boulder, CO
TDI
'02 Golf, Mr. Red
David -
If one isn't going to go your route with the FMIC, Newspeed has the lower IC pipes, although I have not bought one to verify fit. They want so much money for the part, I'm considering making a run of 50 just for us geeks.
The upper IC pipe doesn't impress me as a restriction half as much as the lower one.
 

Sootman

Veteran Member
Joined
Jan 30, 2003
Location
Maine Coast
TDI
2011 Golf TDI
Peter,
That's great news, finally some emprical data (well consistent data anyway) on what mods do what for these cars. Having finally straightened out what seemd like a turbo surge problem (it wasn't) my car is running well and I just need to add some fuel at this point. I'd be interested in coming down when you dyno and see what the numbers look like for both of our cars as we progress through some assorted changes. Maybe Mrchill would like to join us;). Right now I'm holding out for injectors and maybe a few other things including an exhaust upgrade.

Anyway, thanks for doing this, it's so easy to talk about what mods do what but dyno numbers combined with real world driving experiences are where it's at for me at least.
 

n1das

TDIClub Enthusiast, Veteran Member
Joined
Jun 11, 2002
Location
Nashua, NH, USA
TDI
2014 BMW 535xd ///M-Sport, 2012 BMW X5 Xdrive35d, former 3x TDI owner
robert5995 said:
David -
If one isn't going to go your route with the FMIC, Newspeed has the lower IC pipes, although I have not bought one to verify fit. They want so much money for the part, I'm considering making a run of 50 just for us geeks.
The upper IC pipe doesn't impress me as a restriction half as much as the lower one.
I swear every time I look at that lower stock IC pipe, I think about how suspiciously restrictive it looks. I bet EGTs would drop some by getting rid of the stock lower IC pipe and replacing it something more free-flowing. If you have a pyrometer installed to measure EGTs (I don't have one), EGT data should be included in all data collected before and after mods.
 
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Left Coast Resident

Ubẽr Clubbie
Joined
Apr 23, 2006
Location
San Fernando Valley (Los Angeles)
TDI
2001, 2002 & 2003 Jettas
IndigoBlueWagon said:
SNIP
I am considering getting a baseline dyno (my car dyno'd at 135 HP and 260 lb/ft. last year in Baltimore, but I need a consistent piece of equipment and operator to make comparisons) and making the following changes.

- GHL downpipe install with a 2.5 inch exhaust, no CAT, and two 'cherry bombs' to manage noise

SNIP

I may get the exhaust done this weekend as I already have the downpipe.
I was inspired by NathanMSL's post RE his exhaust system, so I went and did something similar. If / when I figure out how to post pix and dyno plots I will, but for now, the exhaust system is:

1) stock 1st bend out of the turbo
2) ramps up to a true 2 1/2" flex joint (bigger than you'd suppose if it's a true -- not a nominal -- size)
3) bells into a Magnaflow / Car Sound 60010 3 1/2" spun aluminum, metalic, 300 cell diesel cat -- not cheap
4) 3" mandrel bent tubing all the way back
5) to a single 3" in, dual 2 1/2" out Magnaflow muffler
6) into 2 Magnaflow 2 1/2" dual wall tips (3" O.D.)
7) neatly staggered out of a 1.8T cut away valance

I couldn't get any info under 2900 RPM, as the conveter would keep unlocking, so I don't actually know what the peak torque is, as the torque is over it's peak and sloping down at all points on the graph. If there's a simple method to posting the images, let me know and I'll do it. The dyno's, in words, are:

Before: 130 HP / 228 ft lbs at 3000 RPM, 123 HP/ 152 ft lbs at 4250 RPM.
After: 140 HP / 242 ft lbs at 3000 RPM, 139 HP / 172 ft lbs at 4250 RPM.

The spread is not even -- there are plently of other points in between where the spread is much smaller. However, the butt dyno said it is faster and more responsive at all throttle positions. It is expensive if you really want it to be pristine, but despite this, I'm very pleased.

Al
 

TurbineWhine

Veteran Member
Joined
Sep 16, 2005
Location
Asheville, NC
TDI
Jetta, 2003, Platinum Grey
IndigoBlueWagon said:
We all know that the way to more power is more fuel. But if you put in more fuel you need more air to clean up the smoke. A larger turbo will give you more air, but perhaps allowing the VNT-15 at 18.5 PSI better intake and exhaust will increase its flow as well, allowing me to increase fueling. After these steps I can then add an 11mm pump. And if that gives me a big boost in torque I may then add a cam to increase HP.

quote]

Hello IBW,

I think you really need to carefully consider the cam option. In a zero-clearance Diesel engine, like we have, a performance cam is really big bucks for extremely little gain. Talk to TDIRacing about this. I talked with him at length during the Asheville, NC GTG, about this very issue since I had you bring me a cam that I have to replace and I was weighing the benefits of a performace cam myself. He has done a tremendous amount of work in this area, relative to our engines.

TW
 

Coinstarpatrick

Active member
Joined
Jan 5, 2007
Location
Houston Tx
TDI
2001 Golf GLS TDI (Candy White)
While cleaning my intake with some other TDI-clubbers (thanks by the way), I really saw how restrictive the lower intake tube is (The one that connects from the turbo to the airbox, not sure of the exact name). I think a REAL CAI for our cars would have to go from the turbo all the way to the airbox location. I think if that was widened and smoothed out power could be gained.
 

20IndigoBlue02

Top Post Dawg
Joined
Aug 22, 2001
Location
Was North NJ, now SoCal
TDI
2002 Golf TDI-- deceased
Coinstarpatrick said:
While cleaning my intake with some other TDI-clubbers (thanks by the way), I really saw how restrictive the lower intake tube is (The one that connects from the turbo to the airbox, not sure of the exact name). I think a REAL CAI for our cars would have to go from the turbo all the way to the airbox location. I think if that was widened and smoothed out power could be gained.
He's already got a OMI to take care of that
 

david_594

Top Post Dawg
Joined
Feb 28, 2004
Location
Cheshire, CT
TDI
2000 Jetta GLS Silver
Not to refer to the vortex too much, but why dont we consider their way of testing mods.

Hook up the vagcom and then get on a nice open road and do a pull through 4th gear(maybe 3rd) loggin maf reedings. Do it a couple times and you should see pretty consistant results in regards to the max airflow according to the maf.

Then make whatever changes such as the cold air intake and hop on the same road and do the same thing. If the mod actually makes a difference in airflow it should be reflected in the MAF readings. This would defenitely be applicatable way to gauge mods between the turbo and the motor, so the intake manifold, pancake pipe and intercooler mods.
 

Gothmolly

Veteran Member
Joined
Feb 3, 2005
Location
Providence, RI
TDI
2002 Golf
So without going with the FMIC kit from Kerma, and without trying to source a nonlisted Neuspeed part, and despite the fact that the lower IC pipe thread on here died w/no details, does anyone have a source/price/picture of the lower IC pipe?
 

TdiRacing

Vendor
Joined
Aug 19, 2003
Location
Baltimore, MD
TDI
2006 Jetta TDI Cup
IndigoBlueWagon said:
- R32 DSG airbox and snorkel (if I can locate one) with a larger MAF holder and intake line and something smoother than the 'dryer hose' that currently goes to the intake.
This will make your car run like total crap. The whole injection system is based on mass airflow. If you use a larger housing, the ecu program will have to be totally changed to compensate for the larger housing and the difference in mass airflow.

many people have tried this already using the 3" MAF form a 1.8t. Jeff can re-write a program to compensate for this if you want to try it. At that point you might as well just go RC4.
 

mycruiseagent

Vendor
Joined
May 2, 2001
Location
Zephyr, TX
TDI
Jetta GL, 2002, Galactic Blue - R.I.P.
Oliver is right on this Peter. The MAF is designed to detect flow RATE in a known orifice (the MAF housing) - the ECU takes the signal and does the math to calculate the total air mass and adds fuel to match. If you change the size of the MAF housing the MAF will give a bogus reading (it can only give a 0 - 5V signal - it's no smarter than that). If you use a large housing the MAF will give a low signal to the ECU and you will end up with less fuel (at best) or limp mode or CEL as the ECU may find the low flow it thinks it is seeing implausible.

Other than that... you're thinking fine. ;)

MCA
 

robert5995

Veteran Member
Joined
Apr 8, 2006
Location
Boulder, CO
TDI
'02 Golf, Mr. Red
Molly - Neuspeed's got them, but as stated above, they want so much money for them, I'm considering a run of 50 for us geeks.
 

IndigoBlueWagon

TDIClub Enthusiast, Principal IDParts, Vendor , w/
Joined
Aug 16, 2004
Location
South of Boston
TDI
'97 Passat, '99.5 Golf, '02 Jetta Wagon, '15 GSW
Thanks guys, lots of good ideas. I've got a larger intercooler (TyrolSport) and Jeff ran some logs with it last February: He reported he could see it's helping quite a bit. I have a set of PD130 intercooler pipes which are larger, and I may try those. On the exhaust side, the GHL downpipe is 2.5" from the turbo back, and I plan to stick with 2.5" all the way to the bumper, where I may split to two smaller turn-down pipes for appearance and reducing the soot collecting on the wagon's butt. Mandrel bent would be very nice, but I don't think that's in the budget right now. And the Magnaflow spun CATs are beautiful, but I think I may go commando on that for now.

On the intake side I talked with Jeff about the larger tubing and he said he can adjust the MAF readings to compensate for the lower air velocity. So I'll be OK there. I probalby won't put in the airbox and piping until a GTG when I can get him to fine tune the car. And I won't consider the cam until everything else is done. I've talked with the folks in BC about their cam as well as with Jeff, and he says it's a trade-off: you give up torque for HP, basically. I would be interested in the cam mostly if torque gets higher than I want and I'm not seeing an increase in the top end. I have the G60/VR6 clutch combo, and it's never slipped with the 260 ft/lbs (right?) I'm making now, but I'm keeping a close eye on it.

David, I like the idea of the VAG logs: I will do those anyway, even if I dyno. I have just the piece of road for it.

Keep 'em coming!
 

clove911

Veteran Member
Joined
Apr 27, 2004
Location
Harford County, Maryland
TDI
2001 Golf, blue
If you have a stock intake we can swap onto my car, I would be willing to meet with you for some dyno's. You know how my car is setup, and I want some more dyno's after some upgrades. Unfortunately I think your talking pretty soon, where as I need some time to finish some things up before I can drive the car that distance. Either way interesting stuff, i'll follow for sure
 

Gothmolly

Veteran Member
Joined
Feb 3, 2005
Location
Providence, RI
TDI
2002 Golf
TdiRacing said:
This will make your car run like total crap. The whole injection system is based on mass airflow. If you use a larger housing, the ecu program will have to be totally changed to compensate for the larger housing and the difference in mass airflow.

many people have tried this already using the 3" MAF form a 1.8t. Jeff can re-write a program to compensate for this if you want to try it. At that point you might as well just go RC4.
He is going RC4.
 

IndigoBlueWagon

TDIClub Enthusiast, Principal IDParts, Vendor , w/
Joined
Aug 16, 2004
Location
South of Boston
TDI
'97 Passat, '99.5 Golf, '02 Jetta Wagon, '15 GSW
No RC4 for me: I'm still going to use the VNT-15 so I'm limited to 18.5 or so PSI of boost. MrChill loaned me a VR6 MAF holder today and it's significantly smaller in diameter than the opening in the R32 airbox. ETKA, here I come.

Edit: Found the numbers, now to source.
 
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david_594

Top Post Dawg
Joined
Feb 28, 2004
Location
Cheshire, CT
TDI
2000 Jetta GLS Silver
Haha, yeah. That r32 airbox is freaking huge! Check on vortex, you should be able to get a vr6 airbox shipped to you for less than $25. Thats what I paid for the airbox and snorkel.
 

IndigoBlueWagon

TDIClub Enthusiast, Principal IDParts, Vendor , w/
Joined
Aug 16, 2004
Location
South of Boston
TDI
'97 Passat, '99.5 Golf, '02 Jetta Wagon, '15 GSW
Yes, but I like the R32 one: I can spend a lot of $$ on intake stuff if I'm not putting in a turbo.
 

david_594

Top Post Dawg
Joined
Feb 28, 2004
Location
Cheshire, CT
TDI
2000 Jetta GLS Silver
No, you just use the top half of the vr6 box because thats where MAF attaches to. You then use the lower half of the r32 box because it has the nice big snorkel and all.
 

oldpoopie

Vendor
Joined
May 14, 2001
Location
Portland Oregon
TDI
2001 golf gl, 2006 jetta, 1981 ALH swapped rabbit pickup, 1998 beetle
Agreed about the VR6 maf housing. I've run one, and the only reason it ran well is because of Jeff's maf delete programming. If you want to run with the maf, you've got to get the air tables adjusted. I'm really thinking about getting this r32 snorkle though. Nice. I'd seen that thread when it was new over on the tex. I'll definately get that setup when they are back in stock at impex.
Arizman3 said:
Piece that goes under the headlight: 1J0 805 962 G B41
IMPEX SKU # 332849
Special Order European Part
This European part is a special order. Prices may vary due to fluctuations in currency exchange rates. Please call 1-800-736-3550.
Manufacturer: GENUINE PART
Price: $16.07 More info...
Intake snorkel: 1J0 129 609 G
IMPEX SKU # 331954
Special Order European Part
This European part is a special order. Prices may vary due to fluctuations in currency exchange rates. Please call 1-800-736-3550.
Manufacturer: GENUINE PART
Price: $42.27 More info...

1stvwparts:
Airbox:
Part Number: 1J0129607AK List Price Core Price Your Price
AIRCLEANER $125.07 $0.00 $91.55
piece that goes behind the headlight:
Part Number: 1J0805965EB41 List Price Core Price Your Price
ADJUSTER $5.30 $0.00 $3.88
For a parts total of $153.77 sans shipping or exchange rate diffs.
"cold climate" version: 1J0 129 607 CC :

IMPEX SKU # 331945
Special Order European Part
This European part is a special order. Prices may vary due to fluctuations in currency exchange rates. Please call 1-800-736-3550.
Manufacturer: GENUINE PART
Price: $213.51 More info...


Modified by Arizman3 at 8:54 AM 6-13-2006
StoicDude said:
Apparently the Germans figuered this one out, and the DSG airbox(bottom part) seems to be a perfect fit, and the tubing is much bigger than the 1.8T. This is again from the German info I got (www.gti25.de), and they are saying that the 6MT box is different than the DSG box. I dont know why.
Here are some of the pics of what it is supposed to look like.
If anybody can confirm this and send pics, I would be very interested in taking the airbox and tubing of your hands.
I posted it in the classifieds section, and have received two responses, but nobody was able to send me the pics to confirm this.
The dealership has the same part numbers for both R32 and 1.8T. I did a search and couldnt find too many pics that show it.
Left R32, Right 1.8T

R32

1.8T top, R32 bottom

R32 left, 1.8T right
 
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KROUT

persona non grata
Joined
Aug 26, 2005
Location
JAX FL
IndigoBlueWagon said:
I've been debating about going to RC4 with my '02 wagon but continue to hesitate. Right now it's running RC3 with PP520s, a lift pump, Oldman intake, TyrolSport SMIC, and a 2.5" exhaust from the CAT back. I've been very happy with the car's performance, but as mod-addicts know, we always want more. However, there are several things I'd like to try before going the VNT-17 RC4 route. There's another thread here asking about CAIs, and I still wonder if a moderately modified TDI can benefit from more air. So here's my plan.

I understand DentSport, a performance shop about 40 minutes from me, has purchased a dyno. I am considering getting a baseline dyno (my car dyno'd at 135 HP and 260 lb/ft. last year in Baltimore, but I need a consistent piece of equipment and operator to make comparisons) and making the following changes.

- GHL downpipe install with a 2.5 inch exhaust, no CAT, and two 'cherry bombs' to manage noise
- DG race pipe or gutted EGR
- CCV mod
- R32 DSG airbox and snorkel (if I can locate one) with a larger MAF holder and intake line and something smoother than the 'dryer hose' that currently goes to the intake.
- PD150 intake or reasonable facsimilie

We all know that the way to more power is more fuel. But if you put in more fuel you need more air to clean up the smoke. A larger turbo will give you more air, but perhaps allowing the VNT-15 at 18.5 PSI better intake and exhaust will increase its flow as well, allowing me to increase fueling. After these steps I can then add an 11mm pump. And if that gives me a big boost in torque I may then add a cam to increase HP.

After getting a baseline, I could probably dyno (a) with the new exhaust (b) with the intake changes, and (c) with the pump changes. Jeff R. tells me the larger MAF holder and hose may require some chip re-tuning as the air will be flowing slower past the MAF. I could get that done before the post-intake dyno.

I've been thinking about this and talking to people about it for a while, but I welcome comments if you have direct experience or data on similar efforts. Opinions only or speculation is less helpful.

I may get the exhaust done this weekend as I already have the downpipe.
I have a larger maf housing and noticed no difference with anything as far as tunning goes. The car ran just like it did before I went to the larger housing.
 

mrchill

TDIClub Enthusiast, Super Secret Diesel Ninja Vend
Joined
Sep 16, 2003
Location
MASS! home of THE WORLD SERIES CHAMPION RED SOX! x
TDI
96 B4v red \ 98 Mk3 green\98 Mk3 Jetta black\ 99 Mk4 Jetta green x2\ 99 Mk4 Golf silver x2\ 99 Mk4 Jetta black\ 97 B4 sedan green\04 JSW gold\03 JSW silver
Muy interesante verdad? I think I may try and airbox (have wanted to for some time but too busy with hid's and navigation). If it works, I'll know immediately. For instance, the omi makes a difference in power depending on your mods. It makes a larger impact on smoke reduction if you smoke. Perhaps an upgraded box will reduce smke at wot (as I suspect) and also release some top end power. I keep saying I'm going to do it, this time I will!
 

oldpoopie

Vendor
Joined
May 14, 2001
Location
Portland Oregon
TDI
2001 golf gl, 2006 jetta, 1981 ALH swapped rabbit pickup, 1998 beetle
KROUT said:
I have a larger maf housing and noticed no difference with anything as far as tunning goes. The car ran just like it did before I went to the larger housing.
Chances are Jeff programed your RC4 with maf delete. The way the maf delete works is that it will use the values the maf gives as long as they are valid... When you changed to the larger maf housing, the values or readings the maf is giving the ecu are no longer valid, and the ecu switches over to MAF delete, running open loop.
 

KROUT

persona non grata
Joined
Aug 26, 2005
Location
JAX FL
oldpoopie said:
Chances are Jeff programed your RC4 with maf delete. The way the maf delete works is that it will use the values the maf gives as long as they are valid... When you changed to the larger maf housing, the values or readings the maf is giving the ecu are no longer valid, and the ecu switches over to MAF delete, running open loop.

I dont have the maf delete. I have talked to jeff about getting it. It made no difference in the way the car ran. I have the maf housing from a vr6 with the upper air box also. Been running it for about 80,000 miles no maf problems all readings look normal with vag-com.
 
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