Dfz 1.9 Turbo Engine, Advice And Experience Required!

[Bigtimmy 1]

Hi all,

 

As you might have been reading in my Track Hack thread on here, I have recently put together a great little track car which is constantly evolving.

 

The engine in the car right now is a D6B and is pretty standard apart from some colourful hoses, a baffled sump, mocal oil cooler and a K&N. It is great fun and I'm learning to drive it properly but I'm sure by the end of this year I'll be ready for some more power.

 

I could tune this engine with carbs, cam, mappable ignition etc and end up with about 170hp and a well tuned engine which will do.

 

I could go the MI16 route, but I'm pretty sure that as someones sig says "16 valves are for men who like to touch other men" or something like that. As I am a hairy chested oaf I'll be leaving that alone thanks very much!

 

I would like to rebuild something to a good standard and make it the best it can be. The engine that came out of my track car is a later model 1.9 DFZ engine which runs a lower CR and produces about 102hp, I have the engine, I know it is good, so I thought why not rebuild this one!

 

So I have come up with the following and have done some research, using the search function on here!

 

What I need is some advice on what to be thinking about next.

 

I'll give you my research so far.

 

I used the search function came up with 2 useful topics on DFZ engine tuning, one from late last year and one from '06.

 

Last years topic was quite useful in giving me some basics of the engine and how to tune it in normally aspirated form to get maybe 150 reliable hp, but this didn't really seem pointful and the thread was unfinished.

 

The article from '06 was more about a turbo conversion which looks like fun.

 

Towards the end of the article there was a post from Henry Yorke who ran a CTI with a DFZ, XU10J2TE exhaust manifold and turbo, XU9 inlet and throttle body, with no dizzy or afm but on a coil pack with Motronic 3.2 ecu

 

So my questions are as follows,

 

1. Am I right in thinking the Motronic 3.2 on some later spec DFZ cars was re mappable for fuel and ignition?

 

2. I guess I need the XU10 exhaust manifold to run the turbo from and thats why I couldn't use my XU9 4 branch?

 

3. Why no dizzy and afm on Henry's set up?

 

4. Is it worth doing some head work, i.e. big valve head, polish and port?

 

5. The standard cam is better for this application as it is low lift and low duration which is better on a turbo engine?

 

6. This would run with my standard loom?

 

7. Has anyone other than Henry done this conversion and can offer any advice.

 

So there it is, my next project, a turbo lump for the track hack!

 

I'd really appreciate any advice that could be given on this, as there isn't a lot of advice on it, probably because there were so few DFZ's produced!

 

Thanks

[Tom Fenton 1,542]

1) The later spec Motronic I believe can be remapped to some degree. Henry uses the standard 2.0T stuff on his car.

2) Yes you will need the turbo specific exhaust manifold. Luckily it will fit all the 8v heads.

3) No dizzy or AFM as the 2.0T management doesn't use either.

4) Every little helps, but I would not expend too much time effort or money on this part of it.

5) The standard cam is better than what? cam?

6) No.

7) Look for my project turbo build. May give you some ideas but you'll need a while to read it all.

[welshpug 1,662]

Are you after Boost or N/A power?

 

 

not 100% but I think the DFZ used flat topped pistons and a larger chamber in the head, swap said DFZ head for a D6B head that might have smaller chambers and you'd have a nicely bumped up compression ratio ideal for running a lumpier cam.

 

IIRC Damir knows more about the DFZ engines that I do.

[Bigtimmy 1]

Hi Welshpug,

 

I think the boost option looks like a more fun option with reasonable power gain out of the box with plenty of tuning options.

 

I learnt a lot about the engine from last years thread with Damir putting some useful stuff up there.

[Bigtimmy 1]

Thanks for the reply Tom, I'm putting the kettle on and I'm about to engross myself in your build!

[wracing 19]

I used the hi compression compression 1905cc engine @ 9.6:1 and it performed very well in my opinion no need to run lower compression!

 

thanks

 

james

[Henry Yorke 269 3 Cars]

Full write up on here: http://psooc.com/forum/showthread.php?t=67433

 

Most of the 205 Gti's in Australia have the 105hp (75kW), or DFZ engine. The piston

has a small dish (9cc) and the chamber volume is quite large at 49cc. The pistons are

quite unique in that they sit only 0.001" down the bore. The camshaft is very mild.

It's common down under to shave 2mm off the head to get the CR to 10:1, or fit the

DKZ head. The head itself is a quite poor. It has small valves, 39/33mm and the

casting is very rough with core shifts being common. It's also expensive to fit larger

valves as there is not enough seat mat'l and the valves are only 105mm long (due to

deeper combustion chamber).

 

The 105 hp cam duration is 218 deg. @ 0.050" and 0.405" lift on both exhaust and

inlet. It's a very tame cam, designed to keep cranking pressures high with the low 8.4:1

CR. The JAZ engine has 0.445" lift on the inlet and a bit less on the exhaust. It has

more duration than the other cam, but less than the 130hp cam. I can't recall all the

numbers.

 

As Tom says:

1. Yes but quite expensive. Chipwizards can do it for approx £400 all in which includes rolling road set up and a map specific for your car. They desolder the existing chip and put a new one in I believe. Not easily upgradable.

2. Yep. No turbo hole in yours! You can use a Turbo Technics manifold if you wanted and that would give you a choice of turbos, not the very expensive XU10J2TE one. The Peugeot turbo is not as crap as everyone makes out if you want a wide usable torque band and very little lag. It is very drivable, especially on track as there are less gearchanges if mated with a 1.9 box. 1.6 is a bit wild though I think Tom runs one but his management lets him rev it high.

3. Coil pack and MAP sensor. MAP sensor is built into ECU and runs up to just over 1 bar before it trips out. No big boost on Motronic 3.2.

4. Opening up a can of worms! Logically you can put an XU10 head on with bigger than GTI valves as they have large chambers. However the headgasket mating faces may be a bit thin in areas and the boost may not like it. It has been done though. Not sure of the chamber capacity of XU10. I went for a head skim, decoke and the thickest decent quality (Spesso) gasket I could find. Gasket was not cheap IIRC. My theory is the air is under pressure so there is slightly less reliance on flow compared to a normally aspirated.

5. See above quotes for cam info. I saw no advantage to change mine for a GTI one.

6. I had mine reloomed. A 406 / XM loom ends up with the wires coming through the bulkhead by the hot turbo and an ECU by your drivers headlight! Not ideal, though some "tuners" may deem it acceptable!

7. Toms is the closest to mine (though I think Miles may have been toying with a Gentry auto). However mine is much closer to what you are trying to do.

 

Those DFZ engines are usually mated to auto boxes so pretty unthrashed. I have had no problems with mine in 3 years But I only run half a bar on a brand new turbo and get 164 bhp but loads of torque (195lb/ft) and that is on a standard 2.0T ECU map. With proper management there would be a lot more in it and more boost could be run safely, but it is enough for me (well my wallet!)

 

Here is it verses a GTI6 205 at Llandow

so you can compare. He couldn't get past me until I let him past, but then couldn't get away so they were pretty well matched.

 

Hope this helps

[Daviewonder 533 3 Cars]

A little off topic but Henry would you be able to post a full size engine bay pic please as im unable to view full sized pics as im not a member.

 

Cheers, Dave

[Kobayashi 35 2 Cars]

very interesting project coming up.

 

did i get you right that there are some "later" DFZ engines running on a Motronic 3.2 from stock instead of the early L-Jetronic?

if so, in what cars could one find this engine management?

[Bigtimmy 1]

I'm back from my mammoth readathon!

 

25 brews and 2 packs of chocolate hob nobs later and I've read Tom's article which is just an awesome feat of both engineering and also photo taking and write up. Well done!

 

I also read Henry's aticle over on PSOOC and that was good reading too as it uses my exact engine spec to do the conversion, which is ideal!

 

I need to do a bit of thinking now about what to shop for, although I wrote a fairly long list based on Tom's article which covered about 2 rolls of andrex list making paper!

 

With having a car that works and goes well reduces the need for me to rush this build and in that respect I'll be doing a full strip down of the DFZ and a rebuild to make the engine the best it can be. It will also allow me to use my powder coating machine to get all those little bits nice and shiny! Sad isn't it!

 

I have a few bits left to do on Team Whitey and some real work (damn it) to do over Easter and then we'll be on it, although in reality I'll probably just crack on with it!

[petert 591]

The more work you do making the head breathe, the less boost you'll need to achieve a given output. Having said that, you're really stuck with the standard small valves as they're 105mm long rather than the normal 108mm. I'd just be giving it a 3 angle cut and porting what's left.

 

The DKZ cam is proberbly the best choice as it has more inlet lift. I'd avoid the 130hp cam as it has more undesireable overlap.

 

Buy some decent manangement so you have easy control of the ignition curve.

[Henry Yorke 269 3 Cars]

A little off topic but Henry would you be able to post a full size engine bay pic please as im unable to view full sized pics as im not a member.

 

Cheers, Dave

Struggling to upload a pic here tonight for some reason. :s PSOOC site is free to sign up to the forum etc.

 

very interesting project coming up.

 

did i get you right that there are some "later" DFZ engines running on a Motronic 3.2 from stock instead of the early L-Jetronic?

if so, in what cars could one find this engine management?

No 205s ever came with Motronic 3.2. The last 1.9 ones came with Motronic 1.3 IIRC but that doesn't have a MAP sensor or coil pack

 

The DKZ cam is probably the best choice as it has more inlet lift. I'd avoid the 130hp cam as it has more undesirable overlap.

Will the extra lift make a significant difference to my engine setup? It has been 100% reliable for 4 years so I would rather not mess with it unless there were big gains.

[Kobayashi 35 2 Cars]

No 205s ever came with Motronic 3.2. The last 1.9 ones came with Motronic 1.3 IIRC but that doesn't have a MAP sensor or coil pack

 

ok, that was my knowledge so far, too.

i did not necessarily think of 205s only when referring to the inquiry about a "3.2 on later dfz engines", but it probably was a misunderstanding.

 

thanks anyway.