My project Corsa, AKA Cecil

[yodacraig]

Nice mate cheap that aswell

[andrewt1971]

Only a small update.
Block and head back from machining



checking and adjusting the piston ring gaps



Checking the bearing clearances




All needs a proper clean now and then I can start to re assemble it.

[andrewt1971]

gave the bores a good scrub then test fitted the pistons to check the deck clearance


then fitted the rings to the pistons


Now awaiting gaskets,seals etc so I can continue.

[andrewt1971]

So its been while since my last update... Basically I got the bottom end mostly built up, was having a tidy up and had a small accident, I dropped the short motor, breaking the corner off the block and bending the crank!


So I stripped the ,luckily, undamaged pistons and rods out and had to find another block and crank and have it machined and re check all the clearances.......
I then came to the next problem, early cranks have two flats that drive the oil pump like this.


Later ones have six flats like this,


The later pump bodies don't have the crank sensor bracket that I need, luckily the pump rotors are interchangeable, however somebody at GM decided to change the oil seal diameter to a different, dumb, size so the pump body was dropped off for machining to take the later seal.


I then built up the bottom end and fitted back in the car before I could damage it.


Then lapped all the valve seats and built the head up with new springs, seats and retainers


and dropped that back on the block


Because the head and block have been skimmed I checked all the valve timing (forgot to take a photo with the dial gauges on) found the exhaust to be spot on but the inlet cam was advanced 4(cam) degrees so I redrilled the gear ten teeth plus 4 degrees retarded, pictured here before I timed everything up


All back together, doesn't look any different to before.


We've been out for a session to bed everything in, no fluid leaks so should be able to start winding the boost up at the weekend

[azza15]

Phenomenal thread/build this fair play, an absolutely crackin read

Rotten luck with dropping the motor! Good to see it all back together and running though!

[andrewt1971]

Cut the bonnet for extra ventilation



need to make some guides and gurneys now to finish them off.

[andrewt1971]

Todays progress..
Started with some cardboard to get the shape correct I wanted for the guides and gurneys






Cardboard patterns ready for making in aluminium


Let the aligami begin







Next I will polish the aluminium and use them as tools to make carbon ones.

[andrewt1971]

Polished the aluminium and put some shuttering around the edges

Bagged up ready for infusing.

Also have bought a good selection of ratios for the gearbox and a few spare parts.

These will allow me to gear for speeds between 45-58 mph in first and 110-150 in sixth.

[andrewt1971]

Air guides straight from the tool


Start trimming


Test fit


Bend up some mesh to keep rocks, wildlife, small children out.


Hold it all in place with wire and lollipop sticks whilst the glue sets



And after the adhesive cured.

[andrewt1971]

A small update. I needed to do something with the bulkhead closure plate where the gear selector used to go through so.
I removed it from the car and weighed it of course...


Trimmed it back to leave the flange and screwed it to a board


Filled and pattern coated the plate


Flatted and polished


Mould pulled and polished


Layed up and infused


Pulled from the mould


Trimmed and weighed, a 130g saving.


Steel hold down nuts


Replaced with aluminium, another 50g saved


and the plate fitted


Also I have been doing a little mapping but have had to order bigger injectors as I've run out of duty at 1 bar boost at 7200 rpm.

[andrewt1971]

Not much of an update as I haven't been able to do any proper work on the car for three months, mostly because of continuously poor weather, but I did take it out for a little mapping session the other day and tested the launch control on a slightly damp road, all went well until the launch control switched off and then it just spun the wheels.

[andrewt1971]

Another small update, In an attempt to get a wider range of boost control I've decided to ditch the regular BCS and actuator setup for a garrett electro-mechanical actuator usually found on VNT diesel turbos. One of the ideas been that I can force the waste gate open when launching and stop the engine effectively going into anti lag and building boost.

First task was to source an actuator that's PWM controlled and not can bus, turns out a 6nw008412 will do.

So remove the standard parts.



Then make a bracket the mounts the new actuator on the stock mount.





Fit a 2 pin plug on the actuator and earth it locally to the bracket and a ball joint on the actuator arm, this and the above bracket means I can easily swap straight back to 'normal' if I have to



Actuator mounted and aligned with wastegate arm





And a small, extremely dull, video of the wastegate under control of the ECU. Apologies for the quality but its not easy trying operate the camera whilst not burning you arm or melting the camera and changing the ecu map settings on the laptop..

All I need now is for lock down to ease so I can go out and map it, Knowing my luck id' get pulled by the police and I Don't think they will believe its 'neccessary travel'!

[andrewt1971]

Another small update.. My custom short(er) stroke crankshaft arrived today, its only taken 72 weeks!

[andrewt1971]

Not much done with Cecil except a bit more tweaking of launch control and my boost by gear settings...

[andrewt1971]

For a while now I'd been thinking about moving the engine oil radiator and ducting it and the gearbox oil rad together. The engine oil cooler wasnt causing any issue in front of the water rad and intercooler I was just after better packaging..

So armed with some cheap aluminium I set about it.














The gearbox rad sits directly behind. When I have some time I'll pull the aluminium panels off and replicate them in carbon.