G-Teched my 1.6TD - Part 2

[VWRacer]

Couple of quick questions, Mark.

This is a 1.9 head on a 1.6 block, right? Any porting done of the head?

Is the GT20 the same thing as a VNT20?

Thanks!

[935racer]

Yes it is a 1.9 head on a 1.6 block, I have done a substantial amount of port work and there is stil more to come. I also modified the deck of the head near the valves to improve airflow, this made a huge differnence in flow and in overall engine sound. There is still more headwork to come however and maybe some pics as well. The gt20 is not a vnt type turbo it is a traditionally wastegated turbo.

[malone]

This is a 1.9 head on a 1.6 block, right? Any porting done of the head?

Yes 1.9 on 1.6, and only the intake ports were ported. 935racer did some deck mods as well.

Is the GT20 the same thing as a VNT20?

In what aspect? Anyway I don't have a GT20v that uses VNT, my GT20 has a wastegate. Both turbos can't really be compared.

[VWRacer]

Thanks for the quick reply, Mark, I was trying to place the GT20 in the pantheon of turbos, and one of my questions was if it had the variable nozzle.

Deck modifications? :shock: Is that the deck of the head or the top of the piston?

[malone]

Thanks for the quick reply, Mark, I was trying to place the GT20 in the pantheon of turbos, and one of my questions was if it had the variable nozzle.

Deck modifications? :shock: Is that the deck of the head or the top of the piston?

Yeah the VNT20 or GT20v (with VNT) are quite popular in the hot-rod diesel community (TDI in particular) so it's easy to assume that my GT20 is VNT.

As 935racer put it just above my previous post, the deck of the head was modified. Pistons are unmodified OEM.

[Giles@PerformanceDiesel]

hi guys

Marks pump already has the full governor removal mod

when i did his pump it had all the good stuff done

100 % fuel increase over stock with no increase to the no
boost setting.

almost 20 deg pump timing advance

the limitation to the fueling is due to the rotary camplate inside the
pump.

at speeds above 5000 the rollers on the cam start to skip and you
don't get the full pump lift anymore.  i have increased the tension
on the internal springs but with the current parts we're using i can't
upgrade to the Cummins return springs.

i can only use the Cummins springs if we upgrade the Head, cam plate
drive shaft and a few other pieces too.

i can only geuss the price of all those parts. maybe $1500

Giles

[VWRacer]

Thanks for adding this important information, Giles. For my purposes this is still "not too bad" news, since my objective is endurance racing anyway, and where 140 hp will make me competitve in my class (ESR, where the 110 hp gasser Spec Racer Ford is king in races longer than about 6 hours).

Giles, rather than adding stiffer springs, is there another pump more appropriate for sustained high RPM running, or is 5000-6000 RPMs going to be about the max for a mechanical pump?

Thanks!

[vwmike]

hi guys

Marks pump already has the full governor removal mod

when i did his pump it had all the good stuff done

100 % fuel increase over stock with no increase to the no
boost setting.

almost 20 deg pump timing advance

the limitation to the fueling is due to the rotary camplate inside the
pump.

at speeds above 5000 the rollers on the cam start to skip and you
don't get the full pump lift anymore.  i have increased the tension
on the internal springs but with the current parts we're using i can't
upgrade to the Cummins return springs.

i can only use the Cummins springs if we upgrade the Head, cam plate
drive shaft and a few other pieces too.

i can only geuss the price of all those parts. maybe $1500

Giles

What do you mean by drive shaft? Are you referring to the shaft which connects to the sprocket and is there a need for the larger one?

[malone]

hi guys

Marks pump already has the full governor removal mod


when i did his pump it had all the good stuff done

100 % fuel increase over stock with no increase to the no
boost setting.

almost 20 deg pump timing advance

the limitation to the fueling is due to the rotary camplate inside the
pump.

at speeds above 5000 the rollers on the cam start to skip and you
don't get the full pump lift anymore.  i have increased the tension
on the internal springs but with the current parts we're using i can't
upgrade to the Cummins return springs.

i can only use the Cummins springs if we upgrade the Head, cam plate
drive shaft and a few other pieces too.

i can only geuss the price of all those parts. maybe $1500

Giles

Thanks for the info Giles this is a little more detailed than I gathered from 935racer's phone conversation with you.

I want to say that your pump seriously kicks ass, it's a major contributor to this TD's performance. Basic pump DIY stuff doesn't cut it. Now that 935racer managed to make this car virtually smoke-free with his head work, I have to get back to you for more fueling solutions! It's like the story of a general developing a superior tank during World War II - he takes the tank to a armour builder and tells them to develop an armour that will resist a shell. He then takes it to an armourer and tells them to make new shells that will pierce this armour. Then he goes back to the amour builder again for an armour upgrade and so on.

Giles, would it be possible to get custom TD style return springs with tension that is comparible to the Cummins springs you mentioned? Accompanied with a mild 10mm or 11mm pump head upgrade it might do the job without needing to spend excessively on other Cummins parts. I need to rev higher. I didn't buy heavy duty valve springs for nothing! How did the TD drag vehicles that rev up to 7,000 RPM do it?

By logic I'm not sure how Cummins return springs would help me rev higher. Cummins have very low rev and although their springs are stiffer, throwing in a high lift camplate might negate my chance to rev well past 5,000 RPM. A 12mm head also seems to have reliability issues after the 5,000RPM point. I've seen a few explode.. including a friend's whose I sent a 12mm head to.

Regardless, have you by any chance built a TD pump like this and found good results past 5k RPM? Say up to 6,500 or even 7,000 RPM? I understand if you haven't because this is an extreme TD example, 1.6L even.

Your contribution to TD performance is greatly appreciated.

If, ultimately, revving past 5,000 RPM with 10mm or 11mm head and custom TD springs is not feasible, then I will consider going the Cummins route and keep my powerband below 5,000 RPM if required to maintain pump reliability. Could have lots more torque to get a fair increase in HP. This would further necessitate a compound turbo setup.

Cheers,

[Giles@PerformanceDiesel]

hi again

i have some new ideas about it but i'm not going to share. just to tell
u that i will need a 11 or 12 mm head to use and then change some
other parts to match it

i think that i can do it.

u give me the head, your pump or another one and i'll make u a pump
that will rev 7K!!!!

i'll love to try it.

when i drove bryson's old 1.6L that was dynoed at 125HP and it had no
problem rev to 6K

Giles

[malone]

hi again

i have some new ideas about it but i'm not going to share. just to tell
u that i will need a 11 or 12 mm head to use and then change some
other parts to match it

i think that i can do it.

u give me the head, your pump or another one and i'll make u a pump
that will rev 7K!!!!

i'll love to try it.

when i drove bryson's old 1.6L that was dynoed at 125HP and it had no
problem rev to 6K

Giles

This'll be an exciting development. I'll contact you very soon

Cheers,

[greggearhead]

I'm excited and I am just reading about it!

[Mark(The Miser)UK]

hi again

i have some new ideas about it but i'm not going to share. just to tell
u that i will need a 11 or 12 mm head to use and then change some
other parts to match it

i think that i can do it.

u give me the head, your pump or another one and i'll make u a pump
that will rev 7K!!!!

i'll love to try it.

when i drove bryson's old 1.6L that was dynoed at 125HP and it had no
problem rev to 6K

Giles

 :shock: Not into speed myself; but if I was then I'd take a large bore head 12mm or whatever and then machine what I think must be one of the main  limiting factors which is the cam plate so that it was a relatively low profile which IMO would reduce potential takeoff of the follower at high speed. Reduced motion of piston has to be a plus for any given quantity of fuel injection compared with small bore... "short stroke theory and all that guff"

Just trying to help; but not easy with the experts here but you never know

[DutchTouch]

Malone,

What GTech model was it? I can't recall a Gtech without "Pro". Here's the product lineup:
http://www.gtechpro.com/prod.html

The Competition Pro (MY 2001) and newer Gteches are more accurate because of RPM calibration, accelerometer calibration, and they show both HP and TQ curves instead of just peak HP numbers. I believe Jake (fpsGTD) has the Competition Pro. I have the Gtech Pro RR. I probably should have gotten the Competition as it's a more economicial choice and seems to work fine.

Gtech Pro SS may not let you upload plots to a computer. FYI to those who read this and is thinking of getting a Gtech.

If talking about a dyno, wheel HP is usually referred to, not crank HP. Crank or brake HP is measured at the engine flywheel. I think vehicle automakers like to tout crank HP numbers instead of the more practical wheel HP numbers because crank HP numbers are higher, which looks better on paper.

Perhaps wheel HP always being inconsistent across different dynos is the reason for using crank HP from the factory. Although the big automakers already have top quality dynos that are accurate but $$$$ to calibrate, not all automakers have them.

Your numbers (avg. ~96 net HP) are very nice with just a 0.205 nozzle upgrade. I have not Gteched an early Passat TDI (just the later TDIs and a couple MK3 Jetta TDIs) but the stock Gtech numbers w/ proper calibration in your car would average 80 net HP.

Gtech is most useful for comparing before/after modifications. Keep your Gtech results in mind, and next time if you get a chip or other mods, you can do another Gtech run with the SAME CALIBRATION to see the actual improvement.

*edit: I estimate your current wheel HP to be 105-115.

Cheers,

Malone.... Been out doing the Steelhead flyfishing thing here in Nor California.... sorry I am so slow in getting back to you.

The Gtech Pro was the 1994 model... and I got ahold of it again and got popped by the cops... The darn thing is addictive, I shouldn't be doing what I was on streets in Los Angeles. Air temperature seems to play a big factor in what I get for HP, as well as fuel.  While the air is denser in winter... I had some summer fuel saved in a 55gallon drum that I ran... I'm seeing 100 to 103 hp with that in the tank, and when I run fresh Arco ULSD which is now winter blend, the Gtech is showing 90 to 95 whp.  What is up with that?  That's like 6 to 10% difference?
One other thing... the summer blend on a cold morning with the engine warmed up smokes like a coal powered steam engined train. Temps are in the mid 40's late night when I do my runs. But damn... I can really feel a seat of the pants difference in the fuel. Maybe it's temperature density differnece for my fuel or my fuel temp sensor in my Bosch VE?

I like to play with the mpg competitions on Fred's and my fuel mpg with the winter blend sucks... I've lost like 6 to 8% on my mpg with the winter blend fuel.  The stuff just doesn't make as much power and the mileage goes down with it too.... I may as well be running biodiesel.

Great thread.... Man I hope you can get 6500 rpm and 160hp from a TD... that will be a major accomplishment in a VW IDIi TD 1.6.

I had a hard time with shipping getting Smog's nozzles into the USA.. the customs folks were tough to to appease... but he sent me a set of VEG 205's and whatever they are... Lordy do I like what they do for my car.

I went to a GTG here in Los Angeles yesterday... Got a ride in a rare Made in Germany 99.5 Golf Coupe with PP520's and one of your chips... The young man brought dyno slips...  139 at the wheel and 292 ft/lb's of torque. The turbo was spiking at 22 psi on his gauge.... this was the day before his Dawes device arrived. He runs it now at 18.  What ever chip he has that you did for him... it is kick-azz for  a TDI, just really impressive 60 to 80mph figures for safely passing a tractor trailer rig on a 2 lane highway here in the USA.

[935racer]

What exactly blows up when a 12mm head is revved too high?