Timing/fine tunning a 1.8 16v.

[dunnettracing 0]

Hi.

I have just finished installing a 2.0l bottom end on my 1.8 16v. I was looking for some advice how to install the timing belt and get the timing correct. Also i herd that it is required to adjust the fueling for the 2.0l bottom end. Is that correct? And is it worth getting a rolling road set up done, What is a rough price for getting this done? Hope i make some sense!! Many thanks Richard

[steveo29 0]

no the belt doesnt control the fueling

 

yes its worth getting it rolling roaded...expect to pay £60 upwards depending on if it needs much setting up

[dunnettracing 0]

Thanks. Doest the fueling need adjusting because of the 2l bottom end?

[CorradoVR6-Turbo 0]

No fuelling adjustment is needed mate as is mechanical fuel injection,so even if you did go get it rolling roaded the likely hood of some one being able to tune the metering head on the K-Jet is remote.

 

Plenty of Club GTI have done this with no more than bigger capacity = more fun...so just have fun :tongue:

 

as for timing here are some pictures ive added to help you out.... :wave:

[dunnettracing 0]

Thank for that info mate, very usefull

[steveo29 0]

actualy most of the cgti peeps get the wur (warm up reg) modified to suit as the added capacity will probably need more fuel at high revs

 

any good rolling road should be able to sort it, stealth is popular for this mod

[CorradoVR6-Turbo 0]

its just a bolt on part to add,im sure its the audi 2.2 ones they use,most dont.

 

Look on club gti mate

[davidwort 0]

a 2L bottom end on the 1.8 fuel system will need a rolling road setup to get the best out of it as steveo29 says

the WUR mod is nothing more than drilling the top off the tamper proof cap on the back of the Warm Up Regulator (needs to be removed from side of head to do this) and adjusting the small allen key grub screw to alter the control pressure of the system.

This will basically run the system a bit richer throughout the rev range and needs to be done so it's not too high on emissions for the MOT but fuels a bit more for the top end (k-jet tends to lean out a bit up there anyway.)

Couple that with adjusting the base setting on the distributor to something like 7.5-8.5 degrees (instead of the standard 6deg +/- 1 deg) running on super unleaded and you can easily get another 10bhp at the top end than you would from just leaving it set up as it would be for the 1.8 normally.

without the rolling road you'll have trouble setting the mixture right (WUR adjustment) and could end up with pinking loosing you power if you over advance the distributor, even if you don't hear/feel pinking it can be starting at loose you a bit of power, the rollers will detect this.

you can do a basic adjustment of the WUR by simply adjsuting the grub screw a tiny amount (say 1/4 of a turn) and making sure you can't feel a loss of power(leaned it off) or over richened it - in which case you'll soon get sooty spark plugs, in fact the plugs can tell you a lot about if you've got the mixture right, what you want for the K-jet is just a little amount of black soot appearing on the shoulders of the plug/end of the threads but nice clean burning electrodes, then it won't be far off the max that it can be trimmed to on the rolling road, ignition really does need the rollers though, as I said, and a lot depends on the condition of your head, has it been poilished and gas-flowed and is it already coked up at all or a clean rebuild, a flowed/polished head is often more resilient to pinking.

[Toad 0]

You could use a vaccum operated WUR from another car such as the mercedes and porsche of a similar vintage to the corrado, apparently these need stripping and reshimming to get the correct fuel control pressure, but do allow vaccum controlled enrichment of the fueling. This should be more efficient than a standard WUR that's been modified as it won't be running rich throughout the majority of the rev range.

 

I don't know a great deal about this, so don't quote me, but I read an article about it the other day, and intend to investigate further. The awkward part seems to be reshimming them to achieve the correct control pressure.

[steveo29 0]

^^the standard 16v one is vac operated

[Toad 0]

:oops:

 

Well, I looked at the vacuum pipe going into it, and didn't put 2 and 2 together in a correct fashion. Lol.

 

Could a different unit work better on a 2l conversion though?

[steveo29 0]

dunno really...if you can afford the dyno time to test them all maybe

 

the wur mod is simple and works pretty well...so id go with that

[dunnettracing 0]

Thanks for all that info. Does anyone have any advice on adjusting the distributor, how do you know how many degrees it has been turned. Thanks

[davidwort 0]

Thanks for all that info. Does anyone have any advice on adjusting the distributor, how do you know how many degrees it has been turned. Thanks

You need a timing light, ideally one you can set the strobe/timing on, this allows you to dial in more advance than the factory 6 degrees on the factory timing marks a tiny rotation of the distributor (a mm or two) will move the advance several degrees.

[nathan.g4 0]

Dunnettracing i am interested in changing the bottom end on my valver to a 2.0L was it hard to do? How much did it set you back roughly?

Thanks Nathan.