Prawn and BigAls A3 Track Car

[Gazwould]

Give you a clue , it's 4 seperate readings...

 

[bigal 1]

No, cylinder pressure. Its leaking like a sieve.

 

[bigal 1]

The interesting thing is that it made 350 bhp and drives well on the road. Although it was pumping oil into the catch can without knowing it. Hence earlier post regarding oil in the can. On taking the head off initially , it was seen that certain components had been installed incorrectly . That should have been a big warning sign. This person, persons do not have the ability to build a proper performance engine. VW specialists my a--e. They should stick to servicing. This engine is a joke.

We do not hold the engine seller responsible in any way.

At Coombe last weekend it was pumping something like 1 litre per two laps into the catch can.

 

[Prawn]

As above really.

It's a shame.

We took a gamble, and it didn't pay off.

I don't in anyway blame the previous 2 owners of the engine. it runs and drives fine on the road, and only the compression test and oil loss on track showed the true story.

I genuinely do believe this has been a bad one from the off though.

there were several issues I found when i stripped it down that suggested the quality of the original assembly was questionable, but being in too deep I had no real option but to persevere and hope the issues had no serious effects.

Turns out, the flaws clearly ran deeper than i knew.

Acceptable compression is 10-13bar, and i have ONE cylinder at 11 bar, the next closest being about 9.7. then 7.5 and 3.7. So clearly it's knackered beyond belief.

How it made 350bhp is beyond me. I really do believe it was like this when it went in, as it feels exactly the same now as it did when it came off the dyno having made 350bhp.

Still, all is not lost, and I knew when buying the engine that this could well happen.

What I've now got, is a decent set of IE rods, and a full supertech valve train to build into a new home.

Whilst the head appears to work, I also found multiple issues with the head when I stripped it down, and some pretty nasty looking cam bearings. Also, cylinder 4 despite having 10 bar compression is really oily inside, so I'm going to cut my losses there and build the valve gear into a fresh head.

I'll be dropping a block, crank, rods, head etc with Bill in the near future, to be bored to 82mm and furnished with some 9.5:1 Wossner pistons, before it's all balanced. The head will be skimmed and have a fresh set of guides fitted., and I'll be building my supertech valve gear into it.

I'm not 100% decided on small or large port yet. Early thoughts were towards small, but looking back I liked my large port engine and the way it drove far more than the small.

the only thing I prefered on the small port was the lower EGTs it seemed to have, but as Bill pointed out, it was a completely different engine, and the EGT drop I saw could have been down to one of many other things that differed from the old engine.

Given my eventual plans to drop in a gt30 or similar I'm beginning to sway towards the large port again.

I'll write up the day at Combe at some point.

There were good bits too, like this in particular:

 

[bigal 1]

Absolutely awesome. Oblivious to the rest of the world. I wonder how fast we would have to go before Oliver rolled off.???

 

[Rainbird]

Not fast enough to warrant the extra 30N of downforce he created. Better to keep him inside.

 

[Gazwould]

Bless his stripey baby grow .

 

[Stuart B]

I assume you vent to atmosphere? as even with a catch-can the oily air still travels through the TIP, charge pipe etc and reduces the power even on my pretty normal (but knackered) engine.
what bit is broken? is it not just the rings leaking or is it the bores, head, valves entire block?
I am just trying to work out whether its worth trying to fix mine, buy a replacement engine or scrap the whole thing.

 

[Lavis89]

Considering those compression readings it would be interesting to see how much power you make on a fresh engine build

 

[scotty_24]

Wonder whats causing the lack of compression, I presume new rings when the rods went in?
If its got supertech valvetrain you would have throught theyd be lapped in and sealing correctly?

As far as my limited knowledge goes:
Rings
Melted piston
Valve
Head gasket
Cracked head

Are the things that could cause the compression leak?

If it was pumping air into the crankcase and causing high pressure blowing out out, would that indicate the issue is in the bottom end?
Blowing by the rings and into the crankcase?

As I say my knowledge is minimal and I would love to know whats went wrong, just so I can learn too. The more I know about these barsteward engines the better.

I live in constant fear that mine is going to let go too even though I've got fresh rebuild rods supertech valves etc etc LOL

 

[Rainbird]

The general consensus at the weekend was blowby pressurising the crankcase, either from knackered rings or bores in one form or other. That was purely from a bit of head scratching though, rather than any actual investigation so all will be revealed once Nick gets a chance to hunt further I'm sure.

 

[Prawn]

What he said

 

[bigal 1]

I could not believe the blowby on idle, it was unbelievable. Catch can pipes undone and oil and air everywhere.

However the past is the past and we are looking forward to a NEW car. It is going to be awesome. Watch this space. !!!

 

[Chris90]

Be following closely

 

[Stuart B]

hi bigal,

so on idle was the blow-by from the cap, rocker blow-by and the filter blow-by, dip stick ?

I have oil leaking down the from of my engine as well as those - I think between the head and block (might just be leaking out the dipstick area) even though the car actually runs okay for normal driving (clearly it is not okay) but its not misfiring etc

 

[bigal 1]

Hi Stuart, the pipe was taken off, on the return from the catch can. The air pressure was unbelievable on idle, blip the throttle and it was massive.

Yours could well be blowby/pressure if oil is being forced out. Again our engine only really showed its major faults on track. It was not misfiring and went well on the road. Albeit oil was being forced into the can.

Try a cylinder pressure test. Speaks volumes.

 

[Stuart B]

yeah I am looking into that - but again I am not sure whether that highlights a general cylinder issue or a specific problem.
eg if it is low - it could be any number of things. apparently you can guess based on other symptoms eg if two cylinders next to each other it could be a head gasket but a single cylinder might be head gasket, rings, bore, valves etc. all it really does is confirm it's knackered - and needs a rebuild.

good luck it's a shame this engine didn't last as long as hoped after all the time and money spent on the rebuild.

 

[bigal 1]

Yes, time and money.!!! This time the engine will be built properly from the bottom up with excellent hardware and a new turbo. Looking for some good sustainable figures. The AGU was a great engine until it picked up a valve, but we knew we were on borrowed time with the valves due to the increase in BHP. It would have been addressed at the end of last season, some two or three track days to go before it went bang. Bad luck or bad judgement. Take your pick .

As you said, it sounds as if yours definitely needs surgery and however many tests you do, if its blowing oil, its ********. Good luck.

 

[Prawn]

So, the dust has settled, it's bank holiday weekend. I may as well write up the episode of Castle Combe and the Spring action day.

Things started out pretty well getting ready for the day.

With lots to do, I was up at 7am to do a quick wheel alignment on the car before work:



I'd found this handy calculator online, which means the strings don't have to be perfectly square to the car, which really speeds up the setup time:




And then after a quick tweak:



This method is more accurate if you use a vernier to measure distances to 0.1mm, but for a quick check and minor change that I needed, this is plenty.

With the alignment done, I drove it to work that morning, and it was feeling really good.

I'd bedded the brakes in on the way to Guildford earlier in the week, and they were feeling strong, the car was pulling straight, and generally we felt ready.

I'd also loaded on a higher boost map, feeling confident I'd solved the minor knock issues caused by oil getting into the combustion chamber.

With everything just about ready, I even found time to have it cleaned for a change!



I offered the carwash guys an extra few quid if they could get the bottoms of the doors clean, but no matter what they tried it wasn't happening. We decided between us that the matte rough finish was infact caused by hot brake dust. That'll teach me to wash it more often in future!

Still, cleaned as best as they could, it was looking good!



We finished work around 4pm, and quickly bled the brakes on the volvo:



Before heading back to mine, loading the A3 up, applying a few stickers Clive / Aaron has sorted for the action day (thanks guys) , then going to pick up some slicks for Andy, and some fuel for the day:



Quick test fit on the volvo, it was looking good!





We arrived at the unit at 6am the next morning, and to my surprise nocturnal Sam was already there in the E36!



We parked up and began strapping the volvo onto the trailer Andy had borrowed:



Whilst the A3 sat outside warming up:



We left a bit later than planned, at 06:38, but with clear roads we were due at Combe shortly after 0800:



I must admit, I had a little trailer Envy!



A quick stop at Tot Hill for fuel and breakfast, and of course a picture of 3





I quite like the slightly more subtle look, a few silver stickers, and the brighter wheels certainly lift the car in my opinion:



McMuffins consumed, and we were on the road again:





Spirits were high for the day ahead!




We arrived at Combe shortly after 8, although due to the huge popularity of the Action days, it was almost 9am before we were inside the paddock, and straight into sound testing:



With things nice and warm, the car blew 91dBa at 4500rpm. It's well under most limits, but I always keep a record of it's results, just incase things start to get louder suggesting some repacking could be done on the rear box. All good so far though. Not bad for a £240 exhaust that's now 5 years old!


I got through an early drivers briefing, and got the car into the pitlane where we were setting up. Our friend James very kindly set all the tyres to 24psi for me whilst the Mission Motorsport drivers had a quick run down of the day with Jim Cameron, Mission Motorsport CEO.




James and I headed out for a few sighting laps, to warm the car up, get some heat in the tyres, and generally check things were OK.

I did a lap on low boost, and straight out of the box things were feeling really good! the car seemed to brake and turn well, and the medium compound NS2Rs felt very good straight from cold.

After a lap I turned the switch to full boost, as that's what I intended to run all day. the car didn't feel quite as quick as I was used to, and on watching the boost guage it was clear that my actuator had relaxed a little. It was slow coming onto boost, and peak boost was a few psi lower now that things had heated up. not the end of the world, and very easily fixed by adding half a turn of preload, but worth noting all the same.

Sadly, what was more worrying, was the amount of smoke I could see in the mirror within a few corners of turning the car to high boost.

Argh. This doesn't sound good. we were at Bobbies, very close to the pitlane entrance, and it was clearly coming from the exhaust, so at this point I wasn't too worried about dropping fluids on the track.

I stuck to the extreme left hand side, and coasted all the way to the pitlane.

Back on throttle once in the pitlane to keep the car moving, and the smoke screen behind became rediculous. With a light tail wind the smoke was engulfing the whole car.

This seemed pretty serious at this point.

The Marshall was kind enough to point out to me that the car was smoking a little, and advised me that I wouldn't be allowed back on track if I had an oil leak. Thanks for that. I wasn't aware!!!

Bonnet up to investigate, and things seem became pretty clear.

Oil at the end of the air filter. Not cool!



I disconnected the catch can drain line to see if there was anything in it:



Ah.

Thanks to @Rainbird for this fetching picture:



2 can play at the daft pictures game



Not a great start to the day.......

 

[Prawn]

So, that's a 750mm water bottle, with around 500ml of pure oil in it, after 2 laps.

Not the best news! but at least it looked good!



We discussed potential causes, and decided that perhaps somehow my crank case return line had hydraulically locked the catch can with 2 routes in from different sides.
We removed all the drain pipework, and reverted back to a regular catch can setup.

Revving it in the pits cleared some smoke, and it didn't seem TOO bad,


so we headed out:



It wasn't to be though, 2 laps with rainbird, and immediately it started to smoke again on full boost. Damn.



Back in again, and we were trying to work out out of it was just oil in the system burning off, or new oil. A small amount was drained from the can again.

We decided to remove my PCV return line to the plenum, incase it was somehow syphoning oil out under braking by being a vacuum on the lower crank case line.



This time @RobinJI s mum Jill jumped in. This was the second Action day Jill had come to hoping to get a ride in the car, and I was pretty gutted that it wasnt looking likely to happen, yet again due to issues!

We decided that by taking Jill out for a test run, she would at least get some experience of what it was like, even if it wasn't a proper representation of how the car should be.

We headed out, and once again, on the out lap the car felt OK, but as I crossed the start / finish to start a first flying lap, I saw the tell tale puff of smoke in the mirrors, and knew it was pointless.

This wasn't a breather issue.

This was terminal.

Back into the pits, and this time we immediately decided to call it a day.

What had been a tiny dribble earlier from the air filter, containted within the bay, was now a full scale flow, risking dropping oil on track too, which is a huge NO.

Plug out of the catch can, and lets see whats in there:



Right, so that's about 600ml, in less than 2 laps!

Clearly my PCV return line had been keeping the can level down by swallowing half the breathed oil through the engine. Nice to know that works, but clearly it was masking the true extent of the problem, and is also probably the reason the issue hasn't come to light on the road.

We removed the oil cap, and pressure in the top half of the engine didn't seem to be that bad.

Removing the crank breather line to the can was a different story though, it was blowing REALLY hard from the crank case. ARGH.

I reconnected both lines TO the catch can, and removed the single 25mm outlet from the can, and started the car again to see just how much pressure was coming from the engine in total:



The simple answer - LOTS!

At this point the car was pushed into the corner and abandoned for the day!

 

[<tuffty/>]

I R Saddened...

<tuffty/>

 

[Rainbird]

A couple I got from the day too:

Left early, though fortunately not quite such an unsociable hour as Nick & Co. as I was staying to the west of Cardiff for the week

Some fun roads to the M4

As I approached the Severn Bridge, there was a significant increase in both fog, and the number of little mini-convoys I passed

I pulled off the M4 and took my place in the queue to get in. At this point I was around 400m from getting in, which equated to the best part of an hour...

Headed over to the pits to say hello to Nick and had a bit of a chat with James who was helping get the Audi ready to head out for an initial feeler lap. @Prawn headed off for his drivers' brief and the two of them headed out on track. It was somewhat short lived.

Obviously something wasn't right, so we popped the bonnet to take a look. Oil in can, oil in pipework. Grim.

Emptied the can, cleaned out what we could physically reach and then gave it a fast idle to try and burn through anything residual in the intake tract. Produced progressively less smoke so things were looking semi-positive.

Content that the car was ok to go back out for another couple of laps to try and diagnose further, we went back out on track. 4 laps later...

Around a pint of oil straight from the can again. ********. Cue a small handful of us trying to help figure things out whilst Nick juggled the car and family duties (including both teams, Oliver/wife and mother/ @bigal 1 (In the fastest 4-wheeled machine there all day)

One attempted solution was to blank of the PCV in an attempt to reduce any small pull it'd give the oil. As Nick's said, this was completely fruitless which was a shame, though now we know a little more, unsurprising. This in turn led to a low and lumpy idle, so the laptop came out to tweak the map to suit. Emerald handiness FTW.

Around the same time this was going on, Andy pulled in with the Red Baron having had a slightly odd noise. Apparently going out on track with one wheel done up finger tight will do that...

Nick went out with Jill to see if we'd managed to bring the oil pumping down to a tolerable level. Even if it was filling a quarter can every few laps it'd be manageable and allow him to take passengers out for Mission Motorsport, as well as to give some stress relief after a pretty disheartening start. Unfortunately it wasn't to be, and just 2 laps later the A3 took up residence in the pits once more. Another pint of oil in the can, plus god knows how much more in the pipework, coming out of the filter, and sitting on top of the splitter (at least it hadn't made its way onto the tarmac!)

And so the A3 was parked up for the afternoon, and family picnics were had. Much better way to spend a day in the sun anyway, right?! Until about 4pm anyway, when Nick and I decided to head back out on track for a final play.

...not in the Audi, mind! We'd pinched Sam's M3 for a quick session and it was good fun (if a little interesting given a distinct lack of brakes after the first corner)

Smiles restored onto Prawn's face, and boosted a little further after loading up the cars and getting back to the more important things in life.

I had planned in heading back to Cardiff again after Combe, but given the way the day had planned out I shot back down the M5 home to see if I could help get things moving back in the right direction.

However, in more recent discussions we might have another plan in mind again now. That will require me to dig a little deeper into my stockpile of 1.8t parts though, so I'm sure Nick can pick things up again if/when that happens!

 

[Prawn]

Excellent addition!

Thanks Luke

 

[scotty_24]

Gutted for you Nick. These cars man, nothings ever easy.

Makes you wonder why we do it.

 

[Prawn]

What smoke problem?

looks fine to me!





Aaaaaaaaaaaaaaaaaaah, you mean THAT smoke problem!



Going...



Going........



GONE!





Slow trundle back to the pits please!




I'll teach this engine a lesson.

11:30, Bank holiday Monday:



Out in time for lunch:



And the engine bay, back to how I'm not used to seeing it!

 

[Russboy]

Small world, possibly not the right thread to bring this up on but Rainbird is the LCR in your pic "LJ03 TXU" your car?

 

[Rainbird]

It is indeed - it's also a complete state at the mo as I've not been able to make time to sort out a few minor niggles (like fitting the new engine I've had in the garage for 12 months...)

Do you know the car?

 

[Russboy]

Yep, just a bit.

1st owner was a competition winner who sold it back to Seat, I was the 2nd owner in late 2003 with a few thousand miles on the clock, this was the day I picked it up:

Within a week it had a Jabba remap & the windows tinted, after that the list was quite extensive from the Neuspeed short shift to the Dynashift induction. I had "66 WYD" plate on it during my ownership, went to Santa Pod a few times, GTI international:

Bristol Volksfest:

I've got 100+ pics of it & only sold it as I had the LCR & my Evo VIII & the LCR was surplus to my needs

Even have a few vids of the LCR

 

[Rainbird]

Small world. Great to find out a little more about the car's former life!

Can't see the photos you've posted, though that might be as I'm on my phone in the dark depths of West Wales. I'll drop you a message so as not to clog up Nick's thread, but it'd be great to hear more and steal any pictures you have of the LCR.

 

[Russboy]

No probs, they should all be set to public, but drop me a message & we can go from there.

 

[badger5]

no pictures

 

[Russboy]

Any better???

Day I picked it up:

And then in no particular order

 

[Prawn]

Fixed

Nice little addition there. It's always cool to find out your cars past.

Unless you're the old boy who now owns my M3, he looked gutted when i told him I used it own it when I stumbled across it at Combe years ago.

He was mid 60's, and it was his pride and joy. he looked heart broken that a 21 year old Prawn had been abusing it in the past, then sold it for a fwd hatch back

 

[Rainbird]

I hear Tori's dad had the same look at your wedding?

Need to get the new lump into the LCR by the summer if work/wedding stuff allows, see if we can raise those dyno plots (and maybe lower those 1/4mi times, if anyone gets me confused enough to have a go at some straight line driving...)

 

[Prawn]

Anyway, back to the a3

I started stripping the engine down last night.

Turbo ready to remove:



Everything looked great on the turbo, which is good news

Cam cover off, all looks as it did when it went together:



Head off and no immediately obvious issues, apart from clearly lots of oil.



same story with the head, aside from all looking fairly heavily sooty and oiled up:



This is number 2, the one that's failed:



Sooty, manky, but on the face of it at least, intact on the crown.

This is number 3, had 7.5 bar compression. Odd mark in the piston on the left in this image:



Seen here too at the bottom:



I think any assessment of the engines running condition is out due to how much oil it was swallowing, although the plugs do at least appear to be a half sensible colour:

 

[badger5]

pictures might be exxagerating things but there seems to be quite some gap between cylinder wall and piston.. Rock about a lot do they?

 

[Prawn]

I kinda thought that too Bill, but I thought maybe I was seeing things.

There is a LOT of piston slap though. Lots and lots.

Thankfully I only need the rods from this bottom end, and I will take great pleasure scrapping the rest.

 

[Chris90]

Thats actually pretty noticeable now you mentioned it Bill. Be interesting to measure the piston to bore clearance and compare it to what its meant to be.

Maybe someone thought of the idea to put some oversize rings in it?

 

[Prawn]

In other slightly less depressing news, after over 2 years, my Reyland discs finally cracked:



Usually this would be sad news, but given they've lasted 4 times as long as the previous discs, and pad life has been much improved with them, I'm not too unhappy about it at all.

Also, in a change of events from my usual **** luck, ebay looked kindly on me, and these popped up for a pleasing sum:





Lightly used, but they've been ground, so the surface is as new. Zero cracks or signs that they're run hot at all:





Vernier confirms condition, 28mm new, 26mm min thickness:





So that's 70% and 80% remaining. Conveniently the 80% disc is the front left too, which is good as our car has always worn left hand brakes at a slightly faster rate

Oliver confirms this was a good deal by Roaring at me with pleasure



Have a good day folks!

 

[scotty_24]

Im glad that turbos ok Nick.

Thoughts on compression loss then?
See what the pistons look like when theyre out? Are we thinking worn bore?