1.8 DX Head and engine tuning/refurb advice

I am about to soon start work on restoring my 1.8 DX engine that is now out of the car.  I want to keep the engine standard and dont want to start changing things like the camshaft or flywheel that can alter the driveability/useablity of the car , but I am looking to have some head work done to help the engine breathe better and release maybe a couple more horsepower.

From my understanding this is what would be recommended:

Pressure Tested
Skimmed – if required
Smoothing/polishing to remove Casting, Pitting & Boring Marks
Port Matching to gaskets, inlet and exhaust Manifolds
Exhaust port polish - not inlet
Three angle valve seats cut
Valves refaced
Valve Guides renewed
New valve stem oil seals

I would welcome your thoughts especially if you have had similar work done on your car.

Can anyone recommend a cylinder head specialist that is familiar with MK1 engines?

Secondly, what should I get done/checked on the rest of the engine:

crankshaft balancing?
Check the bores

Anything else??

Advice welcomed.
 

hi there
I am getting similar head work done and was keen to hear of your experience. Have you any advice for me as I am getting low compression sorted on my 1.8DX GTI Sportline - its done 130k and compression is now a little low

Had mine done last year as it was leaking oil into the bores. Well worth it I paid £800 for mine (inc welding where clutch cable came through bulk head and some hole in the bay) engine now feels like new. Depending on your area I can suggest a guy


Sent from my iPhone using Tapatalk

thanks
I am in Rickmansworth, Herts
I found a guy that i trust near Watford after being ripped off by a mechanic in London Colney

£800 - sounds like decent value to me btw

Hi Corwey26

When my GTi broke down due to fuel issues, soon after purchasing it, I decided to do a fully nut/bolt/bare metal restoration.  I therefore had no experience of what condition my engine was in - but at 155K miles and 35 years old it seemed stupid not to have it rebuilt.

I spoke to several engine builders and took advice on here as well.  It seems every engine builder had there own ideas on what is/is not needed.  Much depends on how you plan to use the car - really fast road use/ track days/Sunday pottering etc - and also how much you want to spend! .  He had also extensively flow tested 1.8DX cylinder heads and spent time on rolling roads so he knew just what was required.

The chap I chose has been building racing Golf 1 engines for over 25 years.  I felt from chatting with him that we were "on the same page"  and he clearly had huge experience.

He recommended for mine - which will never be tracked/raced/driven REALLY hard - just nice and briskly -

3 angle valve seat cut,
new guides,
stem seals,
light skim.
Exhaust inlet throats opened / blended to the seats and the ports sufficiently sized to suit your required use.  
Face the head
Check the block

No need to balance crank/lighten flywheel or other parts - way over the top.
No need to "match" the inlet/exhaust openings to the gaskets / manifold porting
Don't need larger valves

I stripped the engine completely to save costs.

On inspecting the block he found it needed a light hone, after which he cleaned it, hot washed it and took out the oil gallery plugs to thoroughly clean it.  It was then painted
 
The valve guide wear was some of the worst he had seen which meant the all the valves needed replacement as the wear was  too much and would be too sloppy in the new guides which would cause them not to seal well as they close onto the seat.  The head was then cleaned up after the machining work and painted.

At this stage I was planning to rebuild the rest myself - however I took the decision that a pro with huge experience would do a better job then me (!) and it would help in providing a warranty on his work.

He therefore rebuilt the bottom end with new parts and rebuilt the head with new items as required.

I then collected the assembled head/block.  Delighted with his work so far - I have had the engine running but not yet on the road.

Hope this helps - do get back to me is you require any further advice.

hi
this really is helpful - thank you for sharing your experience with me.
good questions re: my goals and budget.
I certainly wont be racing or indeed after high performance.
Just seeking a sound reliable, fun drive and if I can recover a couple of horses too then great.

my budget is c£1000. I dont have the knowldge nor skills to attempt such work myself. I have been quoted circa £800 for the head work. I hadnt really envisaged full engine out and rebuild. I had assumed this would be way over my budget.

Just to chime in on this one, I had to have some machining work done on my block - it was rebored to take OEM oversize pistons (I had these), con rods checked for er, roundness (?), fully balanced (but nothing lightened), full set of new shells, new piston rings - that was £700 - I did the assembly myself.
I'd previously bought a 2nd hand head that had already had some work done on it and included a mild road camshaft. Similar to yourself, I just wanted and engine that felt a bit more eager, but still suitable for day to day driving.
Can't tell you how it runs as I've not finished the project yet!

cdgthreesalmons said

Hi Crowey26

When my GTi broke down due to fuel issues, soon after purchasing it, I decided to do a fully nut/bolt/bare metal restoration.  I therefore had no experience of what condition my engine was in - but at 155K miles and 35 years old it seemed stupid not to have it rebuilt.

I spoke to several engine builders and took advice on here as well.  It seems every engine builder had there own ideas on what is/is not needed.  Much depends on how you plan to use the car - really fast road use/ track days/Sunday pottering etc - and also how much you want to spend! .  He had also extensively flow tested 1.8DX cylinder heads and spent time on rolling roads so he knew just what was required.

The chap I chose has been building racing Golf 1 engines for over 25 years.  I felt from chatting with him that we were "on the same page"  and he clearly had huge experience.

He recommended for mine - which will never be tracked/raced/driven REALLY hard - just nice and briskly -

3 angle valve seat cut,
new guides,
stem seals,
light skim.
Exhaust inlet throats opened / blended to the seats and the ports sufficiently sized to suit your required use.  
Face the head
Check the block

No need to balance crank/lighten flywheel or other parts - way over the top.
No need to "match" the inlet/exhaust openings to the gaskets / manifold porting
Don't need larger valves

I stripped the engine completely to save costs.

On inspecting the block he found it needed a light hone, after which he cleaned it, hot washed it and took out the oil gallery plugs to thoroughly clean it.  It was then painted
 
The valve guide wear was some of the worst he had seen which meant the all the valves needed replacement as the wear was  too much and would be too sloppy in the new guides which would cause them not to seal well as they close onto the seat.  The head was then cleaned up after the machining work and painted.

At this stage I was planning to rebuild the rest myself - however I took the decision that a pro with huge experience would do a better job then me (!) and it would help in providing a warranty on his work.

He therefore rebuilt the bottom end with new parts and rebuilt the head with new items as required.

I then collected the assembled head/block.  Delighted with his work so far - I have had the engine running but not yet on the road.

Hope this helps - do get back to me is you require any further advice.

hi there
please can you send me the guys contact details and location too? this sounds like what i want but not sure if my budget will stretch - i wont be able to strip or rebuild - i have no experience of doing this so would need 'drive in drive out service'

hi cdgthreesalmons
please can you give me an update on your experience and how your mk1 is now driving? Any other expeirnece you are keen to share since this last posting?
thanks
Adam