Questions

[MK2 GTI]

Hi everyone, I done a compression test on my MK2 GTI the other month and its looking a bit low so in the future i want to pull it apart and rebuild it. It's a 2ltr 2E block with a 1.8 head.

I spoke to the guy i bought it off yesterday and he said the reason he kept the 1.8 head is because the 2ltr head needs to run a different fuel rail and also other little issues, any one know if this is true? Should i leave the 1.8 head on it or put a 2ltr head on?

Would the 1.8 head restrict it? It runs a 268 neaspeed cam with a port and polished head.

What are some good sites for some 8V perfomance parts? I thought while im rebuildin it i may aswell get it goin better aswell. Any recomendations on what to do, I just want some sites to get an idea what i need to save for.

The guy i bought it off reckons i should get a eurospec head, good idea?

Im up for any ideas i just want to know what my options are with it.

[h100vw]

The 1800 head could do with gasflowing. I had a mk1 with an 1800 and big valve head on it. When I fitted it to a 2 litre it killed the top end and fuel consumption. The consumption could have been the k-jet. I lost 10hp easily.

Another comment on big valves and the road, a mate had a similar spec mk1 but with std valves and in any gear he could get the jump on me, even with a couple of passengers on board. Only from a standing start was mine any better on the road.

At the track it was a different story and I just left him for dead.

Anyway, I'd go for a gas flow and leave the valves std size in a road car.

Out of interest what were the figures you got on the compression test?

I have not heard of any that have had bad top-ends, apart from valve guide wear.

Did you squirt some oil in to see if the rings were gone? And was the engine good and warm?

Gavin


EDIT read the post properly now.


If the head is indeed done then big valves is the next step. Don't go too daft with the cam spec to start with.

I would say the biggest power hinderence will be the injection, guessing k-jet. You should have the mixture monitored on the rollers and I think you'll find it runs weak at the top end. Fitting the warm up regualtor from a 16Valve Golf is a top mod, I might even have a spare in the garage. It has a vacuum connection that richens the mixture under load.

The igntion system is pretty primitive too. You need to run the dissy well advanced to get max power but then it ticks over at 2500. I took my dissy apart and ground the stops back on the bob weights to get more advance at high speed but still retain the 'normal tickover'.

If you have any questions about K-jet ask away. Or get a book on tuning and modifying Bosch fuel injection and read the living daylights out of it. A k-jet fuel pressure gauge kit is invaluable too.

[MK2 GTI]

Sorry i forgot what the readings were but i did put oil in it and it read higher, the engine was cold, I'll test it at work on monday again and write them down this time, the motors not buggered or anything i reckon it will last ages just i want it to go better. Thats why im in no hurry. Do you reckon any bottom end work? I havn't got a clue about performance in these engines but i want it to go noticably better.

[h100vw]

You need to know what it's doing now to assess if it can go better.

The motor needs to be at operating temp to work properly.

I think you'll find the motor is sound and you have gotten used to the power.

I though my MK1 went well and it was 40 hp down when I took it to the rolling road. I fitted a vernier pully and had that dialled in, they swung the timing to get max power and tweaked the mixture too. As an 1800 it produced 177bhp at the crank which is probably about 120KW.

The K-jet could cope with that, the extra 200ccs meant that to get best power at the top end, it was running massively rich everywhere else, which killed the economy. It would do 40mpg at motorway speeds as an 1800 but barely made 30 as a 2 litre.

If you haven't got a vernier pulley, evorobin has one in his Golf that he might sell you. He has a cam in it too which may be of use to you. Have a look in the classifieds as he posted them for sale a bit back.

Is your head hydraulic or shimmed??? Very early mk2s were shimmed like mk1s, most were hydraulic.

You will have the warm up reg I was taliking about on your 20Valve Audi. Which is really the same motor as the Golf with an extra cylinder.

You can tweak the fuel pressure with these regs as well by altering the allen bolt under the anti tamper plug on the back. This is why you need the pressure gauge, so you know how much you have changed it by.

Gavin

[MK2 GTI]

My audi is K-jet and my golf is digifant or doesn't it make a difference. I put it on the rolling road a year back but wasn't happy with it and the guy only just got the upgraded dyno dynamics program and didn't know how to display printouts properly. My golf isn't really lacking power i just want it to go better and i thought the rings are a bit old because i done the compression test and considering the motors done 200,000+ km's and most of those km's have been foot down all the time lol (not by me i have only owned it for a year)

I've already got a neuspeed 268 cam in it or is that cam pretty crap?

My lifters are hydraulic, It's a 92 Australian model.

Heres the dyno sheet, the teacher couldn;t work out how to printout properly because i was the fist car on the dyno since the upgrade.

[h100vw]

need to know why that big dip is there. loss of fuelling?

I would put mony on you not having a chip in the ECU. That would make a good difference.

Thing to do is run it again with the rolling road computer hooked up to record timing, fuelling/mixture and engine speed. Then you can see where the losses are.

There will be nothing wrong with the cam but most Yankee stuff is designed with emmissions in mind. Robins cam would breathe a little better but the vernier would be a good buy regardless.

You say the teacher couldn't work it out. Are you in college? That would be cool to have access to the road for free!!..

Maybe you could get the microtech stuff that is on ebay for 500 bucks. Better than a chip off the shelf as you can set it up for best effect yourself. You would learn loads doing that on the RR.

Gavin

[MK2 GTI]

Im a apprentice mechanic and go to tafe, they have the dyno there and I can usually use it after school if the teachers in a good mood, or if were learning about a certain module that we can use the dyno in.

When i first got the car it was hunting and messing around, Id say thats why the dip was there, I cleaned out the throttle body off all the crap and re-adjusted the idle control switch and it doesn't do it anymore. The oxy probe was also buggered when i done the run. But as you say it probably does need a chip or a microtech ecu.

[86gti]

this also interests me.
im also running a 2E in my mk2, but K-jet...
was thinking of trying to find another motor to build up over time...
dont want anything too agro, just a quick street/ track motor.

[gtimk5]

The 2E went well in that car 86GTI, years ago. I finished 6th outright in the Classic Challenge. |Ptobably grtting a bit tired now. Always wanted to put a 16v in it but it was too nice a car. Thats why I built up Gunter. A bigger motor with more valves would have been nice tho. It handled so well. Much nicer than Gunter ever did.

[h100vw]

Im a apprentice mechanic and go to tafe, they have the dyno there and I can usually use it after school if the teachers in a good mood, or if were learning about a certain module that we can use the dyno in.

When i first got the car it was hunting and messing around, Id say thats why the dip was there, I cleaned out the throttle body off all the crap and re-adjusted the idle control switch and it doesn't do it anymore. The oxy probe was also buggered when i done the run. But as you say it probably does need a chip or a microtech ecu.

Are you sure about the O2 probe, UK GTIs of the same era don't have one. Not saying your wrong just curious.

I still think a good run on the dyno with the mixture, timing and engine speed recorded would be very useful.

Gavin