Issues... urgent help appreciated, trackday on thursday!

Gravelben · Post by **Gravelben** » Tue Apr 05, 2011 7:40 pm

So I got the turbobeasty out on track on monday finally, however the turbo came loose on the exhaust manifold mid-session and by the time I noticed it the hot air had melted a few hoses etc - PCV breather and the wee ones to the boost controller. It also melted a dirty great hole in the cambelt cover, so it was pretty hot under there. Water temp was still fairly stable though in mid-90s, which seemed ok to me?

I've replaced/rerouted the hoses and my mechanic re-studded the manifold today (he had to drill out all 4 of them), [-]but the boost seems to be misbehaving - instead of being responsive low down and pulling the 12psi it was set to before the incident, its lagging and then jumping up to 16... I didn't keep my foot down to see if it would go higher.

The hoses to the boost control are a bit longer now, but I'm guessing its one of two things -

a) I've plumbed the boost tap in the wrong way round - would this have that effect?

b) The (manual) boost control has been stuffed by the heat?

I haven't tried turning it up or down yet as I assumed it would be the same, but I might try that soon in case its just that.[/-]

The other issue is that the brakes went really soft/long in the pedal - I thought it was just old fluid but after bleeding they're still soft, I've just been checking the rear caliper adjustment so might bleed again after that, any other ideas? I can't see any damaged or bulging hoses, maybe the master cylinder is poked? It looks good and clean from the outside but you never know.

On the bright side it was hustling around Teretonga really nicely for the 20 minutes of tracktime I got before discovering problems... but if I can't get it sorted tomorrow then I'm taking the Legacy up for Levels and Ruapuna instead!

Gravelben · Post by **Gravelben** » Tue Apr 05, 2011 10:07 pm

Boost was sorted by adusting boost controlller, I guess mechanic had just wound it right open or something. Now holding a steady 12psi.

Brakes still baaaad though! By which I mean you can just get it to lock a wheel in the wet, but the pedal is on the floor

and only one day to get them fixed or I will be trackdaying 1500kg of Subaru wagon!

zippy2 · Post by **zippy2** » Wed Apr 06, 2011 7:20 am

I would be checking the state of the pads, you may have overheated them if they are not road/track rated as some road pads only last 3 laps (however most also are then ok after they cool).

If you are doing 20 min sessions I would make sure you have good road / track pads

I would also be replacing the brake fluid for sure.

On a side note you might want to look at putting in an approved roll bar if you plan to track the car.

Gravelben · Post by **Gravelben** » Wed Apr 06, 2011 7:50 am

Cheers - I have a rollbar, not MSNZ approved but ok for non-competitive outings.

The pedal is soft/long whether the car is moving or not, which makes me think it isn't the pads.

I've already bled new fluid through but the problem is still there.

WideOpenThrottle · Post by **WideOpenThrottle** » Wed Apr 06, 2011 7:52 am

Sounds like you may have boiled or softened your brake fluid/lines by the dump-pipe or you have a vaccum leak to your master cylinder rubber hose? or stuffed master cylinder/wheel cylinders.

Wot

Euen · Post by **Euen** » Wed Apr 06, 2011 10:17 am

If vacuum to the servo is lost the pedal will go harder not softer as there is no servo assistance.

I assume you have checked for fluid leaks. If there are no leaks I would tend to suspect the master cylinder.

Were you getting good fluid pressure when you bled the system. Any noticeable variation in fluid pressure between the wheels?

Even with the increased pedal travel, are you getting any braking on all 4 wheels.

Have you actually checked how much material is left on the pads? Worn pads can result in a longer pedal.

Gravelben · Post by **Gravelben** » Wed Apr 06, 2011 12:22 pm

Interestingly the pedal was a lot firmer this morning than last night, maybe there was still some air trapped that hadn't bled out properly that worked itself out as it cooled overnight. Got mechanic to give it a quick bleed for me this morning too (while I'm stuck at work) to make sure, its still not amazing but much better than it was.

I'd checked for leaks and bulging hoses but couldn't see anything.

Pads had plenty of meat when I checked last week and surely a 15-20 minute track session wouldn't eat them that fast - but they're nothing great, so I have some Bendix ultimates on the way to replace the front ones.

Gravelben · Post by **Gravelben** » Wed Apr 06, 2011 11:34 pm

Update: after a bit of driving around the pedal seems to have come back to normal, so I'll keep an eye on things and see how it goes.

Gravelben · Post by **Gravelben** » Sun Apr 10, 2011 10:32 pm

Gasket blew out again at Levels, looks like mechanic that fixed it on tues used studs that were a bit too short which didn't help! Had the time to fix it myself with better studs and gasket this time. If it goes again (Ruapuna tomorrow so I'll find out soon enough!) I'll have to find a better solution - there is talk of inconel studs solving the problem on pistonheads and miata.net, which I expect are very expensive! Sounds like a brace from downpipe to bellhousing makes a big difference as well.

Interestingly the soft brake pedal seems directly related to the exhaust leak as it was fine until that happened, and went soft immediately afterward.

Much better feeling with the new pads in now.

Keith Jones · Post by **Keith Jones** » Mon Apr 11, 2011 5:22 pm

I tackwelded the studs to the manifold, and, together with the downpipe to bellhousing brace, I've never had any problems with the turbo coming loose in 5 years of regular racing.

Habanero666 · Post by **Habanero666** » Tue Apr 19, 2011 1:39 pm

Argggghhhh! what have you been doing to the beast??
Yes I would tak weld the studs to the manifold, I also think the brake lines got a little "hot under the collar" when the exhaust gases where let loose

Inconel bolts sound very expensive, but probably cheaper than Gamma Ti ones

Use Nordlok washers on the stud and nut assemblies too.

sprsta · Post by **sprsta** » Tue Apr 19, 2011 4:41 pm

i think you sold him a dud

Gravelben · Post by **Gravelben** » Tue Apr 19, 2011 6:53 pm

Habanero666 wrote:Argggghhhh! what have you been doing to the beast??

This.

Habanero666 · Post by **Habanero666** » Tue Apr 19, 2011 9:51 pm

Nothing it wasn't built for I guess.

Gravelben · Post by **Gravelben** » Wed Apr 20, 2011 11:02 pm

Too right! And its great fun too - though I'm actually thinking about selling it to free up some cash for house stuff, I don't really use it enough to justify the cash tied up in it.

brownie · Post by **brownie** » Wed Apr 20, 2011 11:24 pm

Of course you can, and Kidneys go for good money now days,and you will get away with having one

,Can't drive those to put a smile on your dial..

Habanero666 · Post by **Habanero666** » Thu Apr 21, 2011 8:32 am

You could also spend that sort of money on a Psychiatrist! ( which will no doubt, go towards his/her car)

Gravelben · Post by **Gravelben** » Wed May 11, 2011 9:41 pm

Ah well the decision is made, ad up in classifieds.

Habanero666 · Post by **Habanero666** » Wed May 11, 2011 9:47 pm

Lol I put up my car this week too! I hope we are not growing up

sprsta · Post by **sprsta** » Thu May 12, 2011 7:17 am

so you want it back then jim?

Habanero666 · Post by **Habanero666** » Thu May 12, 2011 10:19 am

sprsta wrote:so you want it back then jim?

Haha, I wish! But I am sure I will spend alot more money on it!
Dangerousssss

Issues... urgent help appreciated, trackday on thursday!

Issues... urgent help appreciated, trackday on thursday!

Turbo

Re: Turbo

wow!

lol

Me too

lol

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