Vanne's lightweight/ interior modification thread

BMWZ4MC said:
How so?
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Well it was a shake down, first time out in bout 5 years or so.. prob really closer to 6, but hey.. and everything has changed, not just the suspension, but literally everything.. normally you shake the car down after a single upgrade, but this has literally pretty much the whole car has been replaced.. even the frame I’ve modified to be able to fit the low slung diff carrier.. everything…

So really the only expectation I had was not to catch fire, explode for blow the engine up.. and we came, we went ,and we saw, and didn’t do either of those 3 things.. so that’s a huge plus.. even ,huge-er was the fact that the frame, together with the diff and carrier , steering modifications and the compete Frankenstein-ed suspension worked together like it was always meant to be.. I am seriously over the moon with how the car handles and behaves. The brakes are unbelievably awesome..

The thing that wasn’t awesome is that the car was down on power..

And that’s a big one, less power than I had when it was NA with its carbon CSL intake and tune.. much much less.. the car would pull fuel at somewhere between 5200 and 5600rpm.. not sure on the exact numbers there, but I have my theory’s. Are they correct? Nfi, I’ll find out when I fix what ive pulled apart atm, but my guess is that the belt is too long, due to having an uprated 72mm pulley and I’ve got the bloody stock belt.

That’s my guess.. that the belt was slipping at low rpm and then really slipping at high rpm (which is why the belt halfly fucked off when it had had enough of that) and thus causing such a fuel rich mixture that the car couldent cope. Not sure if it actually went into limp mode at that stage, but there you go, so I motored around, under 5k rpm, but that was difficult esp in corners..

Just to give you an idea of how much power was down, I was only able to change into 6th at the end of the straight , (keeping it under 5k rpm) heavily on the brakes into turn 1, where as previously , I’d be winding the pajesus out of 6th on the main straight.. I don’t wanna give a time on that as I wasn’t recording.. but it was slow.. still had a lot of fun in the tight twisties, but I can only dream of how this will go when I sort this issue out. (We! Thank you, both me and Josh are on it)

But yeah, I’d recon the culprit was the belt, I’ve since ordered 3 new belts, each 5mm shorter than the last, starting at 6pk2334. I gotta download Josh’s new software and then sign up for another track day when I’ve got this bad boy back together. It’s in pieces atm tracking down some intake piping leaks.

Again, it was an AWESOME day, so much went really right, so much so that I had a huge grin on my face, even when I was swapping fuel as I thought maybe it’s pulling fuel due to old dead fuel.. gotta try something right.. (I didn’t figure out the belt slipping until the day after in the middle of the night when that out of nowhere and came to me like a revelation)

But yeah, even though the SC had issues, it still was a huge success, even just in how the car handeled.

The snag list aside from the engine isn’t too extensive, the most important one on their probably being the overheating of the thermonfan switch. I HAVE to fix that. That’s dangerous as it could cause a fire inside the cabin.

The massive outstanding parts that iam most happy with has to be the Penske rear coilover conversion and the brakes and steering. The steering kit from MRT is such a joy.I can’t comment too much yet on the rear diff, as it didn’t miss behave at all, but then I didn’t push it that hard either yet.

Again, we didn’t crash, didn’t explode or catch on fire.. it was a GREAT day!!
 
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So day before yesterday and today I spend pretty much both days taking the various sections of the s54 apart that may or may not have contributed to the engine issues. Started with buying a leak down pressure kit .. you put this pressure adaptor onto the SC intake, then run shop air through it and pressurize the system…

that started as a HUGE letdown, as the system wouldn’t barely pressurize to 1.5psi. Leaking everywhere.. even out of the injector seats..

So I pulled the fuel rails and the vacuum lines and then started anew. Pulled all the injectors, the-did the seals and then re-installed them into the rail.. closed about 4 vacuum leaks, and then on we went.. system still not holding pressure not able to pressureize past 1.5 psi.. huge leak somewhere..

issue is my compressor isn’t that huge and after airing up, would only last 15 seconds or so, before the compressor kicked back into life, making listening for leaks a real bastard..

I then decide to reinstall the whole SC assembly and piping.. kinda needed to as I wanted to run some of the oil lines around a different way. That was a big job, and took me most part of 2 days to get it back together the way I wanted, and the initial pipe coupler after the SC end was probably the biggest **** on the planet last night..

At 2am yesterday morning I finally got it in the right spot and connected up the silicon joiners and secured the pipes.. I finsished off the piping yesterday morning around midday. Re pressure test and happy to say that it now pressurizes to 12psi. No need to go further as my setup only runs to 9 psi. Leaks down very slowly back to atmospheric.
So happy with that.. check!

okay so plugs back in, coils back in, new belt on, this one is 6pk2325 ,9 mm shorter than the original one.

and then started anew up…

f**k!, still runs like s**t…

scan the dme, s**t load of errors about several cylinder mis firing.. no s**t Sherlock..

then pull out the plugs and replace those with an older set I had lying around, which were from when I replaced the Vannos pump disc.

clear the codes and then run the car…

bloody sewing machine… so smooth… so good…


Phew..

An hour later the car turns up that takes me to work.. but not before some lady down the road comes out yelling and screaming that I am being waay too loud, revving the car trying to chase down the miss fire.. that’s 2pm on a bloody Saturday afternoon.. bloody hell…
 
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So did the track day a few nights ago on the 17th night.. (yep kicked off at 8pm) after the airport got bombed. Was expecting the track night to get cancelled, but didn’t.. I got there really early, around 5 pm and set up my work area as there was a lot of stuff I still needed to do. Was spannerimg in the night before again till 11pm and just didn’t get it finished.. was the first one there and then I thought as only initially a few cards turned up that maybe it did get canned, but by 8pm , I think it’s the busiest track event I’ve ever been a part of.

Car is running good.. not great, but much much better than last time.. still missing some power, but now revs nicely to 6700rpm.. so will replace the belt with the next shorter one.. hopefully that will sort it. I also discovered I don’t like track nights.. you can’t see s**t compared to during the day, and took a lot of the enjoyment out of it as the back part of the circuit wasn’t lit up well at all. No idea if the lights were not working there or for what reason.. that made it really hard..

I’ll replace the plugs, nd swap the belts, but the next one will have to be during the day, the night track sessions are a waste of money for me. Can’t push the car hard enough through the turns, only on the straights.. typical Yammi R1 behaviour. Which isn’t really where this car shines..

that said, no stack or fire , so still had a good day..

I also managed to get a few laps of data logging going for Josh, though where my obd2 port is, with the cable installed it fowls 6th gear. So I had to take it quite easy while logging. I’ve since ordered a 90 degree elbow which should solve that issue.





 
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