5tox mk3 Astra GSI LET

5tox · 07-11-2008, 18:02

Hi all,

After the sucess rebuilding my first engine last winter which was an XE, Ive decided this year to go a step further and have a go at an LET.. (my brothers insist turbo's are the way forward)

Last winters project...

Itll be relatively standard to begin with and then see where it leads, it will ultimately end up in a mk3 astra GSI (i toyed with the idea of a nova then a mk2 GTE but ive always loved the look of the GSI)

rc's thread was a big inspiration

So to begin with i was after a cylinder head cheap as possible, Seanr28 very kindly offered me a head very cheap with 8 bent valves which was perfect for a rebuild

The head arrived soon after and i couldnt wait to get stuck in, just as expected ... 1 cylinder head with 8 bent exhaust valves

Next i started to strip the head down completely to the bare shell, this revealed a nice shiny cool running thermostat

which saves me a few quid!!

i was told that if i tapped the bent valves with a hammer the heads would snap off and sure enough they did with very little effort, the valve guide seals on my XE took hours to remove but this time all 16 were off in 10 mins, i guess theres justa nack to it (i attack one side with a screwdriver and hammer, how do you eat yours... )

so i was left with a tin of internals and a shell of a cylinder head..

(i do however still need to remove the valve guides, im not sure on how to do this yet)

After being soaked in diesel for a week the head is ready to be rinsed down and dried out (a job for tomorrow)

Next on the agenda is firstly to remove the valve guides then to begin porting and polishing (the head has already had some DIY porting work done, probably to remove the casting marks. but im planning on matching the inlet side to the manifold so theres no step)

Im just playing the waiting game with the postman now, awaiting all of the inlet side which is manifold/fuel rail/reg/injectors/throttle body/tophat
cemex kindly offered these at the right price..

steve

mr.rail83 · 07-11-2008, 18:47

cemex is the best ever

cemex is the man if you need help such a top bloke!!

daza1986 · 07-11-2008, 18:51

how long did it take you to do a rebuild on the xe?
im thinking of doing a rebuild as the engine has done 190k

thanks
darren

5tox · 07-11-2008, 19:13

Quote:

Originally Posted by daza1986

how long did it take you to do a rebuild on the xe?
im thinking of doing a rebuild as the engine has done 190k

thanks
darren

it took me about 3 months but that was largely due to it being a winter project (i wanted to stretch the project out) + funding the project, uprated parts dont come cheap :-)

if money wasnt an object and all parts were readily available it wouldnt take any longer than a few days to build an engine... always better to take your time though and get it done properly the first time

5tox · 21-11-2008, 20:05

since my last post ive decided that im either going to try and save this head or start with a new one.. the reason being that i found lots of tiny little holes in each chamber that also cover the firing ring (i personally think its pinking that has caused this as its in each of the 4 chambers, i did a thread here covering it.

http://migweb.co.uk/forums/engines-t...2Apics%2A.html

if i do decide to keep this head ill overcome the problem by getting the head lightly skimmed then permenantly fixing a 2mm shim ontop of the head to lower compression and give a good fresh surface for the head gasket to hug, otherwise im still on the lookout for a bare shell of a head (inc cam caps and valve guides) at the right price..

other than that ive received the inlet side which compromises a manifold throttle body and tophat, cemex and i had a few problems with the postman kindly losing the first set he sent out which also included a fuel rail and injectors, cemex is a top bloke though and did all he could to help along the way!

ive started on the tophat to begin with, as you can see from the pics ive took off the writing ontop giving a smooth finnish, also ported and polished inside (originally the inside is rough as a dogs arse)
im also in the process of taking off the lip at the end which will allow a smooth airflow when using silicon hoses...

... this should hopefully be finnished tomorrow then sprayed in silver hammerite (i may or may not keep this as im toying with the idea of a tx autosport 3" tophat off ebay)

5tox · 21-11-2008, 20:47

Should hopefully be finnished tomorrow, then i can post up some pics once its done... real happy with it so far :-)

(dremel was the best investment of my life)

5tox · 23-11-2008, 14:43

Today i started work on the throttle body,

to begin with i took out the 2 round butterflies and went to work with the dremel giving a nice sharp edge for healthier airflow
luckily my throttle body was the type without the great big restrictive wedge

all of the inside was then polished with the dremel (again for a more crisp airflow)

i then left the throttle body to soak in diesel before cleaning it up

so i now have a nice clean non restrictive throttle body, i know that with a turbo engine these little things dont make alot of difference as the air is forced in rather than sucked in but im the kind of person who worries over these minor details :-)

Throttle body first thing thismorning

and now...

5tox · 25-11-2008, 19:34

Cemex seems to have saved the day again, theres a tps in the post which means that when it arrives i can finnish my throttle body :-)

other good news ... ive bought a complete XE engine for 150 quid, picking it up tomorrow from just down the road

this weekend = spray up tophat in silver and start to strip down and inspect the new XE ... all in all im a very happy chappy

5tox · 01-12-2008, 19:05

Over the weekend i stripped down the new engine and im EXTREMELY happy with my findings,

the cylinder head is in great condition, ive never owned a head like this before that has had so little (if any) taken off due to skimming

the bores in the block have no lip at all at the top either, every other bottom end ive had has...

so the head is off, ive had the hydraulic lifters out, rebuilt and degreased then re-oiled.
(they are in the same order as they were taken out, ive never really beleived that it makes a difference to mix them up but i guess its good practise)

the head is still being soaked in diesel at the moment until i get hold of another valve spring compressor, this week hopefully ill be removing the inlet/exhaust studs along with the valves etc... so i end up with a bare head + valve guides ready for porting and polishing
(my plan is to practise with the first head i bought before getting to work on this one)

Another item im very happy with is my Bailey dump valve, its the DV26 Double piston dump valve (a good choice for running these engines with an AFM)

... And my box of cleaned up goodies so far

5tox · 06-12-2008, 14:48

This morning ive been in the shed and pulled out my inlet manifold,

Once this bits completed i can pretty much build all of my inlet side...

Manifold 1st thing

after a good scrub in some diesel

And the final result with a fresh coat of hammerite smooth silver

Once dry ill start to assemble the throttle body / tophat and fuel rail etc...