Beginners QUestions on boosting TDI

[Union Jack]

Hi,
I'm new to this forum, but have read pretty much all the articles in this section regarding boosting the beloved TDI. Made for great reading, nice one guys!

OK, I'm driving a Silver UK Spec 1998 MkIV Golf TDI 90hp. Lovely vehicle and very spritely off the mark. Most people seem supprised that the car is infact a diesel.

Anyway, I'd like to boost the performance a little, but am unsure where to start really. Can any kind soul point me in the direction of what each of the mods do, how to do them, and if appropriate cost. And in what order is it best to do them.

Also how would any of the mods being discussed affect warranty/insurance. I really don't want to void the warranty if at all possible.

I know this is old ground for you veterans, sorry fellas!

Hope someone can point me in the right direction

Cheers,
Graeme

 

[SeatIbizaTDI]

Hi Union Jack. Welcome to the forum. Keep coming, very nice information here, you´ll see. I was is the same situation as you three months ago, when I bought my ibiza TDI 90hp.

First of all, the warranty issue. Technically, it´s your car and in any problem that arises the dealer must prove that it was the mod that caused it. However, in my case the dealer simply said that any mod in the engine will void the warranty, period. Even if you have the law by your side, it will be a headache to solve these problems...But its your choice. Most mods will not cause much problems, anyway...and as someone said, you only live once

.

For the mods: the first big mod is a chip or a tunning box. It's the only one that allows more fuel into the engine. Most of the other mods will allow more air, by minimizing air intake restrictions (K&N air filter, MAF removal, etc) or by raising boost (bleed, VNT mod). Don´t worry about the VNT mod: we just can´t do it because whe don´t have a VNT15 turbo as US TDI do

.

The box is connected to a port of the engine, tricking the ECU and allowing more fuel into the engine. It´s plug and play (or pray) and you can remove it when you want, no traces whatsoever. Downside: it is more "rudimentar" than chip, in my oppinion.
The chip replaces the original EPROM in the ECU for some improved fuel and boost maps. It adds more fuel, more boost(boxes don´t increase boost) and the engine isn´t "tricked". Its a more high-tech and better solution, in my oppinion. But not all people think the same.

A chip or box will cost about £300/£400, but they may worth it. Of all the people here with chips, all seem satisfied. Just ask Mickey or Skypup

. A box it´s a little cheaper (more for the £300 side).
Best brands seem to be wetterauer (www.wetterauer.de), that´s the one all US people have; superchips also seem good in europe (www.superchips.co.uk), although they don´t get much credit from the US "wetters". I think both should be good.
The tunning box (www.tunningbox.com) may work well, too.

The other mods - K&N filter, bleed, VNT mod are cheaper, and they may work good also. The only one more expensive its a high-flow exaust. However, these mods are mostly for previously chipped and hot-rodded cars.

In a resume, the first big mod is a chip (or box). I´m thinking of getting one myself, as soon as I have the $$$$.

Good tuning, hope that this helps.

Ricardo

[This message has been edited by SeatIbizaTDI (edited March 16, 2000).]

 

[JLL]

Nice overview. I would like to see more posts like this one.

 

[Sooty]

Ricardo summed it up very well, but I’ll warn you it can get addictive.

After the K&N + Chips stage you’ll then start thinking about the suspension & brakes, or possibly the exhaust system. You’ll initially intend to stop after those changes but at that point your hooked. The lure of an additional intercooler, ATB differential, racing clutch, propane injection, water injection, modified downpipe or perhaps an elaborate air intake system to feed the ever hungry K&N cone filter it’s all to come. You’ve been warned.

 

[Union Jack]

Hey,
Thanks for the extremely rapid feedback here fellas!

Sounds to me like the Wett chip is the way to go to really make the most out of the engine. Sounds more 'natural' than the various tuning boxes available

I just want a bit more pull out of the engine really as I tend to spend a lot of time on the motorway.
Tell me, is the Wett chip 'visible' to the VW engineers at service time. Obviously if they opened the ECU, yeah, but is it visible to the diagnostic equipment they use.

Funnily enough, when I bought my Golf, I didn't actually want a TDI at all. The thought of owning a diesel was disturbing!
Prior to the Golf I owned a gorgeous Corrado 2.016v. Damn quick car, (not as quick as Skypup's mind!) but incredibly unreliable and drank fuel for England.
So I wanted a Golf GTI. Luckily for me, they couldn't supply me with one, and the nearest car they had to demonstrate to me was a TDI 90. One test drive sold me the car. And I'm more than happy that I ended up with the oil burner.
My only regret is that I didn't hang on for the wonderfully badged 'GTTDI' or 110TDI to everyone outside Europe!

Sooty, where in central England can we get such mods as the Wett chip? Obviously on a Mk4 it would have to be fitted. This cars parked in SHeffield, so I wondered if you knew of anywhere within striking distance..

Graeme


[This message has been edited by Union Jack (edited March 16, 2000).]

 

[Rocket18k]

In my opinion (everyone has one) free power is the best. I would start with a k&n air filter (inexpensive) and boosts the economy side. Then the exhaust would be second. makes the car breathe better (more power), and again increases mpg.
Next i would look to upgrade the intercooler.
I would also replace the manual (i have manual) transmission fluid with a good synthetic , and use a high quality synthetic oil.
I also like tufoil as an additive in the engine. it is excellent and I have used it for about 18 years and over 1,000,000 miles including a time when the oil change place forgot to tighten my drain plug. My rabbit diesel actually had its oil drain and ran ok

with no ill effects.
I would also look at the map sensor screen removal that skypup came up with.
Then lastly I would wett chip if I wanted more power (and also 1 turn the vnt). Notice that all the other mods add power without added fuel. i would have to guess that one could increase power to the wheels by at least 30hp before wett chipping.

------------------
2000 NB TDI
1999 Dodge 2500 cummins
1981 MB 240d
1985 Toyota Corolla diesel

 

[mickey]

Here's what I'd do:

1. Wetterauer chip. http://www.chip-tuning.com

2. Aftermarket high performance air filter. (Just order whatever Wetterauer is selling this week. K&N, BMC, whatever.)

3. Wastegate vacuum "bleed." (Run a search for the word "bleed.")

4. Stainless steel Techtonics Tuning cat-back exhaust system. (When budget permits.)

5. 17" wheels with 225/45 ZR17s.

6. Shine Racing Services street suspension kit. (Mild lowering, custom rate springs, matched Bilsteins, fatter rear sway bar, and remove the FRONT sway bar and thow it in the garbage.)

7. Willwood 4-piston racing calipers with cross-drilled Brembo rotors.

8. Quaife torque proportioning differential.

-mickey

p.s. Throw a bigger intercooler in there somewhere, while you're at it. Hell, you might as well upgrade to a VNT-17 variable geometry turbo, too. Why not?

p.p.s. Forget it. Save yourself some money and buy a nice Porsche Carerra 4.

 

[Sooty]

Graeme as Ricardo said, in the UK you arn’t limited to the Wett chip’s you have the choice of the Superchips they give an extra 5hp over the Wett ones and are re-programmable.

Neither the Wett or Superchips are visible to any VW diags, the way they work is to replace the fuel and turbo boost mappings with a more sporty version, apart from a different label on the physical chip they have no way of telling – apart from the performance!

For your nearest Superchips dealer http://www.superchips.co.uk/car/dealukfr.htm for a Wett dealer http://212.227.54.20/uk/ausland.html Wetterauer don’t have any dealerships in the UK, although I do know of one person who drove over to Germany to have one fitted – nice weekend break!
Nearest Superchip to Sheffield is Autotronix in Dinnington, I would suggest going for one with a rolling road, then have the car dyno’d before and after the chip.

I would recommend the Superchips, they have that little extra power with a smoother delivery and are re-programmable.

 

[JLL]

TDIs are smoke controled by the ECM so they run very lean under all conditions. Simply adding more air will do little to increase hp. These "free" modifications, like the VNT one turn, can change the responce of the engine they however will not result in an mesurable increased in maximum hp.
If the fuel pump or ECM is set to provide a rich condition then all of the above is out the window. Very small air flow increases will result in large hp gains.

Think before you flame.

 

[Rocket18k]

If the think before you flame was made toward me. I think you should reread my post. The one turn vnt mod was only included with the wett chip. Also reducing internal resistances (in the engine, air intake, exhaust including intercooler, and tranny) as i posted will give added performace and increase fuel efficiency. beefing up the intercooler will also create better combustion. I wasnt meaning to flame anyone, only giving my two cents.

------------------
2000 NB TDI
1999 Dodge 2500 cummins
1981 MB 240d
1985 Toyota Corolla diesel

 

[GoFaster]

JLL, the smoke map is based on the amount of airflow measured by the MAF sensor. Up to a certain point, if you get more air through the engine by whatever means, the MAF will sense this and permit the ECU to give more fuel. However, with the stock chip, there is an upper limit to the amount of fuel that it will provide, and that upper limit is easily reached.

The engine will respond to small changes that improve the airflow slightly, but only until you reach that limit ... after that you get no more power, and you'll need a chip to go further.

My car has:
Airbox intake "horn" removed
Airbox intake screen removed
MAF screen removed (did that an hour ago!)
3" trimmed off the bottom of the inner fender behind the intercooler
Intercooler squeaky clean and no longer being contaminated by PCV

... and it's at or beyond the limit of the fuel delivery curve. Time for a chip ... that's coming real soon, but not soon enough!!!

Brian P.
'96 Passat TDI

 

[JLL]

My "Think before you you flame" was not directed to any previous posts. Only to the self proclaimed experts who historicly flame when they do not understand. I do see why you would think it could be directed to you from my use of the "free." Sorry, no slam intended.

My point was simply you must add fuel for the addition of air flow enhancements to net any real gains in hp.

 

[GoFaster]

... and you would be absolutely right! The free mods really just make sure the engine does what it was originally designed to do, rather than less, due to deterioration etc.

Brian

 

[Karl Roenick]

Sooty, I would be concerned that a VW tech would inadvertantly reprogram the ECM with the new VW tool. I guess you could always go down to your Superchips dealer and reprogam, hopefully for not too much money. Do they have to take the chip out of the car or do they use the OBD port?

 

[Sooty]

Karl as far as I am aware the original VW chips are not re-programmable (Yes I know they are EPROM’s), or at least the circuitry is not built in to the system. A VW engineer is not capable of accidentally re-programming it. They would also have to get around the Superchips encryption system.

Superchips re-programme the chips out of the car. When they want to test a new programme a dummy “chip set” is plugged into the car, this “chip set” is connected to a computer which holds the test values for fuel & turbo boost mapping. Whilst on the rolling road the engine management is reading these test values directly from a computer, it allows instant changes to be made, and for you to experiment with various settings. Once happy with the new values the chips are re-burnt, and put back.

 

[Karl Roenick]

Sieman's SIDIS system, which the VAS 5051 is based on, has flash programming capability ( http://www.kfz-prueftechnik.de/html_76/sidis.htm )

I haven't read anything specific about the VAS 5051's capabilities, but I think someone on the vwvortex said that it can reflash the ecu.

I wrote an email to someone at Siemans-maybe he'll reply.

 

[Sooty]

The circuitry physically fitted to the TDI’s system is unable it to burn an EPROM. I know the A3 & A4 Golf/Ventos use EPROMS (UK ones anyway) as does the latest Audi 180hp V6 engine. The chips that hold the fuel & turbo mapping (which are replaced by the likes of Wett & Superchips) are held as read only within the system.
Other areas of the ECU do use flash chips and those values could easily be re-set or re-programmed, but our ‘chips’ are safe from any flash system.

If it was the case that these tools could completely re-programme our existing chips then we’d all have one, and Wett & Superchips would be out of business. Even if the cost of the tool was prohibitively high I’m sure some enterprising person would hire you one for the day!

 

[ThinkDiesel]

No worries: The Wett chips and others are not detectable with the dealers instruments and I have *never* heard of one being "overwritten".

The chip is the single best bang for your buck upgrade. IMHO K&N filter and performance exhaust on a stock TDI is like putting a huge spoiler wing on on a Honda Civic-- something to tell your friends about, but it is not going to measurable improve performance until you *really* modify the engine for performance.

------------------
Ryan

1999.5 A4 Jetta GL TDI- 5 sp

"Ich mag den Motor Volkswagen TDI sehr. Es gibt nichts wie
Dieselenergie!"

 

[Union Jack]

Sorry about starting off a thread and then not replying back later! Been a hectic week. So basically I'm inclined to go for the Superchip.
This may sound a trifle dull as a question... what happens when you sell the vehicle, will it affect resale value of the car at all, or is it possible to replace the original chip into the ECU, so that nobody would ever know it had been tampered with?

I'm a right sensible old bore ain't I?!

 

[SeatIbizaTDI]

Union,
Why did you decided for superchips? Do you know of any advantage over wett chips? I´m also in the superchips vs wett dilema and I´d like to know more of the TDI 90hp euro spec chipped cars...
Keep posting.

Ricardo

 

[SpeedingAgain!]

SeatIbizaTDI
From what I've read here it seems that the only reprogrammable chip for our engines in the UK for the individual customer are produced by Superchips. Wett chips cannot be reprogrammed which really is a bit backward at this day in age.
In the future you will be able to download upgrades for your E.C.U. from the internet not just from the enginer tuner. All you will have to do is plug in your car, fill in a form with payment details, read the disclaimer press Accept and that is it. With this in the future it seems a good idea to go for the reprogrammable option.
Does any body know how much for the reprogrammable option in the UK from Superchips?

 

[stephenmcdevitt]

Let me know how you get on with the superchips upgrade Union Jack. I see that they now have an option on their website for the 115 bhp TDi with +30 bhp increase, £350 sterling isn't cheap though.

Later