dewismotorsport's Astra coupe

Snetterton race day got off to a crap start, weather was terrible so swapped to my wets only for 3 of the studs snapping when torquing them up, looks like this has happened over time by the shear face, must of been a knock on effect from crash and joints and shaft failures. Either way very lucky not to happen on track. Quickly chiseled the old snapped bits from the hub and un wound from the back with mole grips. Sourced some spare wheel nuts and managed to get out in the last qualifying session. Due to missing my own meant I had to start at the back for both races.




Few pictures from a very wet qualifying







Race 1, started at the back in 38th place setting off I get into 3rd gear and went to change into 4th and the gear cable end popped off again, so I was then stuck in 3rd gear for the whole race, made the most of it, trying not to blow m,y engine up on the straights feathering the throttle. I fought my way through the pack and finished 17th.






(not the best watch)

Race 2, rain had stopped but circuit was still slippy and damp but with a dry line, I made the call to stay on wets while 70% of the grid changed to drys. I again started at the back in 38th, nursed it off the line and through the gears hoping my zip tie fix would hold, got myself up to 12th only for the cable end to come off again 2 laps from the end leaving me stuck in 3rd again so I carried on and finished 13th narrowly missing out on 3rd in class B






(better watch)
 
Race prep for the next race, Silverstone GP 6 hour team endurance race on the 26/10/19

Whipped the old cables out, you can see the plastic clips have broke on the cap and lets it pop off, new cable on route via a sponsor


New wheel studs fitted all round to be safe, also whipped the pads out, removed the glaze on the table linisher and re fitted





Also made an adaptor to lower the front camera as you can't see the best out the front


Other trivia stuff like re doing the headlight alignment as race finishes in the dark, wider 16mm front spacers as the 12mm still allowed the tyre to rub on inner chassis leg
 
Long overdue update sorry!

So the Birket Silverstone GP 6 hour endurance race was a very very wet one!

As a team we worked well and all cars performed well, I did a hour and quarter stint and the car was faultless, handling in the wet was un real and managed a 2.50 in traffic which was a top 10 time which I was happy with as there were plenty of faster cars such as radicals and such like.

Race was cut 20 minutes short unfortunately which didn't work in our favour as we were running in second in class but lapping 10 seconds a lap faster than the team in 1st so only needed one more lap to overtake them. Either way we finished second in class so still a great result.





That was the last race in that car for the season so time to take in apart again and improve some bits, mainly the underpowered engine, at its peak this engine made 267bhp but when changing engines I had the injectors cleaned, didn't realise how bad they were and once back in the car caused it to run really rich with a 10.2 to 10.3 AFR at full throttle, this must of knocked power down to more like 230-240bhp so putting right near the bottom of my power to weight class (240bhp per ton after race weight with me in it).

So with the engine out it was time to strip the engine down and build a better one.
Stripped all my spare Z22SE's to find the best crank, cams and head


First job was to strip the head, valves all out and decided to cut off and weld up the un used EGR valve




Next job was to start porting the really restrictive exhaust manifold ports, then smooth the casting marks out on the inlet side and combustion area. Clean the valves up and re lap. I've fitted Saab B207R exhaust valves as they are sodium filled better at dealing with higher temps.









Then into the parts cleaner before re assembling, used Dbilias motorsport uprated valve springs so that can up the revs to 8k rpm




With the head complete it was time to build the short block, I'd bought a Saab B207R block some years ago as I wanted to run the under piston oil squirters to aid with cooling, decided to take them out before the block went to the machine shop and turns out all the springs inside had either failed or were about to so had to buy new ones.
I'd bought some forged pistons about 4 years ago so took them down to the machine shop to have the block re bored to suit the +20 thou pistons.
I also bought some Eagle steel rods at a similar time so dug them out the spares cupboard, went to assemble to to soon find out they won't fit. I was told they were for the Z22SE but only when getting the pins out I soon realised they weren't. Turns out they are for the American 2.0L turbo LSJ engine which runs a larger 23mm pin instead of the smaller 20mm pin.
So all in all I'd had a nightmare and I had to think fast as it was fast approaching the mapping date of the 31st of march with the first race on the 5th of April.







So onto plan B, take apart the engine I had been using as it's a solid low mileage (53K) one and basically change the rods, Saab head gasket, ARP head studs, oil pump side cover gasket and bolted the head on.
While the engine was out I stripped the sound deadening off the bulkhead and gave it a quick squirt of paint and re made a plate for the water pipes.
I also took the diff to Gripper to get a service and have the ramp angle change to make it more aggressive.
Had some spare ARP flywheel bolts from a old C20LET engine so trimmed them down to suit and fitted.





While the engine was out I rebuilt the gearbox into the low milage box off the vectra b so stripped the shafts out and changed the bell housing, modded the housing to take the front gearbox mount and drilled for the larger breather.
I also sourced a 4.41 final drive and crown wheel from a American Saturn Vue so built it all back up, should be a lot better on track now as always found 3rd and 4th really long with the 3.95 fd.







Next improvement was to make a larger inlet manifold, previous design worked well but I wanted to future proof myself and give myself as bigger volume as I could, 3" inlet and 2 1/2" outlet (from charger). I've designed it around potentially running the throttle body post charger if thats possible





New injectors, yank ones that flow the same as VXR blues, didn't end up using the heat shields.
Engine and box assembled ready to go back in, once back in fitted inlet up and spent far too long messing about with the dipstick tube to get it to sit how I wanted.
Inlet piped up, blow off valve boss welded on and inlet temp boss moved into inlet pipe





Other jobs were to fix the small leak from the fuel rail, the after market dash fittings only have one seal on one of the fittings weirdly, worked for a while but then leaked, so cut down an old standard fuel pipe and then on top of that I added a injector seal that when done up acts as the seal and works a treat.
Bought a new ITG enclosed filter, really wanted this to help reduced inlet temps further, I'm happy with inlet temps currently seeing a peak of 45 degrees after a 20 minute race but I'd like to get down into the low 30 degrees if thats possible so had to add a 3" cold air feed, hole sawed the inner wing to allow space so had to make a smaller 1 litre washer tank





So I needed a feed for the filter so made up a feed box which takes air from the intercooler cut out, meshed it to stop it sucking in all the dead rubber on the track. Siliconed and sprayed the panel and mesh black after the picture.





Quick test start and soon found out the throttle body relocation wouldn't work as it would need a second throttle plate on the end of the charger still because when the throttle is shut it just pumps air out the BOV, I made it so it unbolted and the feed pipe was swapped from the charger end. May re visit this at a latter date but for now BOV has been removed.

Needed more camber on the front coilovers and wanted to do away with the camber bolts as I find they can slip under hard driving, die grinder'd the holes longer and removed the tabs.
Also weighed the car and corner weighted it, I literally can't get anymore weigh out of it so I need to run 290-295bhp to be top of my power to weight class of 240bhp per ton after race weight with me in it.






So in the need to up the power I've added a much smaller 2.7"pulley, plan with going that small is to get good power from low down with the opportunity to limit the revs if need be to get the required power figure I need. I have the option to run unto 8k now with the valve springs but current cams may not be perfect that high up but I have bought a over sized alternator pulley to prevent me destroying the alternator if I do go that high



So with this Covid-19 crap dragging on, mapping has been canceled twice so I've dug out the old corsa turbo 3" exhaust, so will get round to making a new system for the astra before it does get mapped as thats one less restriction, current one is 2.5"


So also with the boredom of this pandemic I've had a few ideas, first off was to buy a Saab B207R engine so I could use the head, and crank for my shelved forged engine. The Saab crank has the correct stroke for what my LSJ pistons need, just need to buy some LSJ steel rods and a Saab TTV flywheel I'm all sorted. Bought this 82K engine off eBay with the plan to take the crank and head off it, will port the head at a later date for the forge engine build


Then bored on eBay one night this Saab 9-3 2.0L turbo B207R came up and ending the following morning, last few seconds bid and it was mine for £400 runs and drives just has a judder below 2k rpm when warm. Plan for it is to use the full engine loom, coil pack, sensors and T8 ECU and use the T8 suite to self map it. Basically a cheaper version of OBD tuner as this software is free. Might not work but speaking to some people who have mapped these ecu's they seem to believe it will work fine. I'm happy being the test dummy as nothing ventured nothing gained.
The box of tricks allows me to talk to the ecu once I knock up a OBD adaptor lead. Will copy the standard map of the car and then see how kitballows me to change it on the running car before I break the car for bits.



 
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Being bored often leads to more eBay purchases, so here we have yet another B207R engine this time fully complete, will just sit on this one until I decide what my future plans are.


Another purchase was a OBD Tuner Ecu, also known as Dutch software. This is basically a standard Ecu but with witch craft inside to allow you to self map it as you would a aftermarket Ecu so I can now make my own adjustments in future.


Car was booked pre lockdown to have the original Ecu mapped so not wanting to lose my money I decided to just get them to do the wide open throttle stuff done on the dyno and I’d do the rest at a later date.
Decided I wanted to run the new Ecu on a 2.5 bar Tmap sensor and run a wideband sensor into it via the spare egr feed so stripped my original loom back to find the wires I needed to make that happen.
Also dug another spare astra loom out to label up before modifying to run the same.
Managed to get hold of a quad battery from work to use as my old battery had given up the ghost



Annoyingly before dyno day my obd elm 327 had got lost in the mail so I couldn’t do a lot of the basic settings before getting there which was annoying so had to push it onto the rollers which is never ideal.
At the rollers and up and running the WOT runs were done and few issues arouse in that the intake tubing was strangling it, car ran 1psi more boost without it so will re design a new airbox set up and the car needs aftermarket cams as it made no more power after 6800rpm so new limit of 7800rpm isn’t needed yet.


Few days later after the dyno my replacement reader finally turned up all be it with a snapped disc but after finding the drivers online I could finally get my own laptop linked up to the Ecu to do my own bits.


Took the car down to a mod test track and did some fuel learning runs and mapped them in, car runs so much smoother now and pulls like a train compared to old really rich map. You can put the Ecu into learn mode and drive it through the revs in closed loop and it stores the info, the cells go green once the Ecu has enough info for that box. Once saved all the blue cell’s are the ones I’ve changed, second is the finished (for now) ignition map.


Thought it would be rude not to take some pictures while I was down there as it was clean and shiny for a change.
 
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Long overdue updated time!

So after the mapping session I ran the logs and realised I'd been maxing the 470cc injectors out


So decided to future proof myself a bit and got some new deka 660's and a 2.6" pulley.


Also got my hands on a ported Saab head thats had +1 inlet and exhaust valves, some stage 2 comp cams, timing ring and got a 6 rib bottom pulley.



Huge thanks to Joe at Max88 Performance for sourcing and supplying all the parts I need for the 2.0L B207R winter engine build.







Chopped up the Saab coil cover and modified it to fit the Z22SE coil pack, bit of trimming and spring stretching and it was done





Got the original supercharger back out and trimmed the snout to suit the smaller 2.6" pulley, trimmed all the excess lugs off it and gave it a fresh coat of paint and gear oil






Fitted the new larger (77mm) LS4 throttle body and made a cold air feed into the filter as the other wasn't performing as well as I hoped. Now draws some nice cold air from behind the cut out enlarged grill









Made a cold air feed for myself as when racing inside the car gets very hot, bought some 2" tube and a kit car vent that can be angled and closed if needed and ran it off the old cold air feed next to the brake duct. Works a treat with a nice bit of air coming in.




Restarted mapping and kept getting a throttle related fault codes P1514 and P1515, so I stripped the throttle body plug and replaced it as the clip had broke which wasn't securing it properly. Also re did the Tmap wires, shortening them and re wrapping.
Got rid of fault code P1514 but not the P1515, bit of research and turns out it can be from a air leak after the throttle body so at short notice Joe at Max88 Performance sent me a new charger gasket, also a timing ring fore the Saab lump so I can still run the OBD Tuner software and I stuck a new set of plugs in it.






Treated myself to a SPA oil pressure and oil temp gauge which has built in warnings, a new 4.9 sensor AEM UEGO Wideband and a AEM X series boost gauge which has a handy peak setting so I was able to do some runs and see how much boost I was getting. Peak boost was hitting 16.3 psi but I was still getting the fault issue on start up, idea and occasionally whilst driving. Found a possible leak on a intercooler pipe join which had maxed the clamp out so not making a full seal. Checked the spares box and typically of all the clamps I had, the were all the same size. With a track day the next day I made a temp fix.







Quick blast round the test track and belt decides to spit itself off and wrap round the snout before snapping, enough force to spin the pulley over and around (can see the marks don't line up) and crack the manifold.




Better to happen at work than at the track, whipped the car apart welded the inlet, sorted the pulley and put a new belt on and I was back in the game.




Early Morning drive up to Bedford on the 12th of October for the trackday, used the 3 sighting laps for a fuel learning session, came in and processed them and tweaked a bit more fuel out the top end.
Morning was eventful, had to pull over on the main straight when the bonnet started trying to lift as the bonnet pin was sat a tiny bit too high, adjusted that and was fine. Then got black flagged for noise, my exhaust has got a bit louder and I hadn't got the super trap on the end, they warned me and let me carry on once I'd put the super trap on and told me where the microphones were and to back off or short shift past them.
New belt then decided it dint like the high rpm's and would slip after 6000rpm so I just made do with what I could.
car was feeling quicker than it ever has, new final drive has transformed the car and its such fun to drive, making decent power lower down with 16.4psi of boost.
About 1530 the the bottom boost pipe off the manifold decided it no longer wanted to play and popped off, got the tow of shame back to the pits just as the heavens opened so I just loaded it and headed home to avoid the traffic.


















With a 6 hour endurance race at Silverstone GP on the 24th of October I got back and stripped the front end off again, I've decided to re make all the boost pipes and make them all one size, so ordered a 2.5" intercooler kit so I will cut the 3"pipes off the intercooler and make new ends. Also ordered a 15mm shorter belt and will add the 6 rib bottom pulley to allow more belt grip.

 
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Few other bits I've been doing on the side:

Got a CAD file drawn up to make some thermal gaskets out of nylon and got them cut on the new machine at work.



Finally got round to buying a helmet hook, instead of balancing it on the dash


Replaced a seized electrical cut off cable


Weighed the car on the wet wheels and with minimal fuel to give me a better after race weight



Also cleaned all the paint off the new head as it was dual colour and really not to my taste

 
Looking good as always.
Bare ally looks better than painted I think.
Still quite chunky even with all the weight its lost, how does it compare to a factory stock car though out of interest?
 
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