Simple Engine Performance Upgrades

[johnhenry 20]

Evening all

 

after many conversations and searching; ive come to the conclusion that this subject area has many offers of opinion, but im struggling to establish what is factual help, and what is opinion, or what essentially a sales pitch for their part.

 

Im after essentially a rounded engine improvement. so making it more steady/reliable as well as improving output if possible.

The engine will be being rebuilt including the bottom end, so it will be out of the car, making upgrades easier to make.

 

Im throwing the floor open to suggestions about improvements from you guys. think of it as a GTI+ what im looking for. There are a host of other upgrades im happy with for the rest of the car, so im not just wanting a better engine, the cars being looked after well!

 

Cheers

John

[GLPoomobile 958]

If I was doing this, I'd focus on engine management to improve overall refinement (or rather, introduce it ), economy, and performance. You can do that on a comparative budget by using Motronic from a later model (something like mp3.1 I think it is) and then having that mapped (I think it's Chipwizards who can map Motronic).

 

Welshpug and Pugtorque should be able to add some clarification to that.

[Miles 331 1 Cars]

That engine should have the Motronic on it already being a GTi CAT engine.

Really depends on your budget but you will have to spend a fair amount for any gains I'm afraid

[camgti 56]

Agreed with the refinement comments. While its apart and you have the funds. Lightening and balancing things makes for a smoother motor. Perhaps look at raising the compression and a having minor headwork done and a cam to match. As said above, power costs money. Also look a your choices of gearboxes, maybe shorter ratios to help speed things up to suit the motor and your style. There is quite a lot of reading on here to be done on this topic. Check out some of the Build threads to get some insight to motors being built. There is also this one over on the Aussefrogs.com site http://www.aussiefrogs.com/forum/showthread.php?t=86864

 

If you really keen, you could look at using a DZF bottom end with a DKZ head. Gives about 10.8.1 compression from memory. That, along with a nice cam and headwork would be great!

 

Cam

[feb 47]

Since the Motronic gives mappable ignition why does the Motronic engine make less bhp and torque than the Jetronic one?

[Tom Fenton 1,542]

Since the Motronic gives mappable ignition why does the Motronic engine make less bhp and torque than the Jetronic one?

 

I stand to be corrected as I don't claim to be any expert on the Motronic later 205's, but I would say it is due to, 1 lower compression, and 2 shorter duration cam. Both of these done I would suggest for emission reasons to work with the CAT.

 

However these paper figures are only half the story, as the Motronic cars probably still make closer to their stated power, whereas the Jetronic cars vary massively according to how knackered the AFM is, and where the dizzy is set.

 

I'd have thought upping the CR and replacing the DKZ cam with the earlier cam, alongside a rebuild to get back to where it should be, and then a remap if needed to suit, would liven up a DKZ.

[Miles 331 1 Cars]

They drive so much better, for the sake of a couple of BHP in most cases it's not worth worrying about, Mind why they fitted this and not the Coil pack version who knows

[johnhenry 20]

thanks for the input guys, it has however raised another issue.

 

I have checked the cars chassis number, it is a XU9JA, so would have been a LE2 Jetronic, the engine in now however is a DKZ, which is a metronic...

 

A Metronic system has these:

a) A double barrel throttle housing is used with 2 throttle vales acting simultaneously

An oxygen sensor is fitted to the exhaust system, allowing fine mixture adjustment to enable use of a catalystic converter.

c) A TDC sensor is used to provide the ECU with information about the crankshaft speed and position

 

I dont have A, B But i dont know about C, how can i find out? moreover if i dont, whats filling its space? the DKZ id plate is fitted to the bottom end of the engine, so it would look like i dont.

 

So from what i can see/deduce, i have a DKZ (Metronic) engine, running a D6B (Jetronic) injection.

 

The million dollar question, What does this mean?

 

all i can think is its a XU9JA with lowered compression. the XU9JAZ is 9.2:1, the XU9JA is 9.6:1

 

Many thanks John

I know this is an odd turn for this topic, apologies.

[Anthony 1,003]

a) A double barrel throttle housing is used with 2 throttle vales acting simultaneously

That's incorrect. M1.3 management / XU9JAZ engine has a single throttle just like other 205 GTi's, although it does have a plastic inlet manifold.

 

Crank sensor is located in the top of the gearbox above the flywheel, which if it's the XU9JAZ one will have the 60-2 Motronic timing teeth on it (flywheels on Jetronic models don't have this)

 

As for what does it mean - chances are that someone's popped the original engine and replaced it with one from a CAT-equiped 205, and they've just used the existing Jetronic management. Rough outcome of that is that you've got an underpowered 1.9 engine without any of the advantages that the Motronic management offers.

 

Ripe for turbocharging though

[smithy 1]

That's incorrect. M1.3 management / XU9JAZ engine has a single throttle just like other 205 GTi's, although it does have a plastic inlet manifold.

 

Crank sensor is located in the top of the gearbox above the flywheel, which if it's the XU9JAZ one will have the 60-2 Motronic timing teeth on it (flywheels on Jetronic models don't have this)

 

As for what does it mean - chances are that someone's popped the original engine and replaced it with one from a CAT-equiped 205, and they've just used the existing Jetronic management. Rough outcome of that is that you've got an underpowered 1.9 engine without any of the advantages that the Motronic management offers.

 

Ripe for turbocharging though

 

 

thats exactly what i am going to do,i had D6B originally that was a bit tired i got hold of a DKZ minus management.Rebuilt the DKZ and fitted with jetronic from the D6B.

I am going to get the rest of car finished and then go down the turbo route,out of interest what is involved with turboing one of these and is there any guides knocking around on best turbo to use and how to fit etc?

[Tom Fenton 1,542]

Get beer.

 

At least 4 tins.

 

Then read this

 

http://forum.205gtidrivers.com/index.php?showtopic=87784

[omega 82]

Get beer.

 

At least 4 tins.

 

Then read this

 

http://forum.205gtidrivers.com/index.php?showtopic=87784

 

tom

with the best will in the world the above can not be classed as a "simple performance upgrade"

[johnhenry 20]

Thanks for all the input everyone!

Have been chatting with a family friend who used to know 205s fairly well, we are thinking that, from data on the site and other sources, the DKZ is essentially a lower compression'ed and different cam (Maybe??) D6B engine?

so would in theory you be able to create a XU9JA output engine by changing said things over?

 

As for Mr Fentons build, that is pretty much a 205 bible or quality skills and process, one of the first threads i read, albeit fairly vaguely so i will go over it again tonight!

[Miles 331 1 Cars]

Yes the cam is different,

Not sure how the Compression on these is different but will know in a few days when I take the head off of mine

[Tom Fenton 1,542]

tom

with the best will in the world the above can not be classed as a "simple performance upgrade"

No, but if you read the last post on the first page you will see why I recommended that person read it.

[smithy 1]

Thanks Tom will have a read through that thread.

 

As above the DKZ has different cam also I think the pistons are different to lower the compression.

[johnhenry 20]

 

Crank sensor is located in the top of the gearbox above the flywheel, which if it's the XU9JAZ one will have the 60-2 Motronic timing teeth on it (flywheels on Jetronic models don't have this)

 

 

ill go have a look, this is clearly visible right? please excuse me, its my first proper in depth strip down and im still finding things.

 

Also, is there a chance it may still have the D6B head on it?

as the engine ID plate is on the bottom end, im wondering if there is any way to check without the head coming off??

 

regards

John