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vw_john

boost pressures

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didnt know where to post this really, but here seemed best.

im looking at buying this corrado, thing is its about a 4 hour round trip. so been asking the owner a few questions.

the car has done 90,000miles and has never had a charger rebuild, i asked her to get the mfa boost results as shown on this list i found on a website

 

Start engine

Move the MFA selector to "2"

Press and hold the MFA end button (keep holding)

Stop engine

Start engine

Release the MFA end button.

Press the MFA End button one time.

 

You should now see 550-750 readings fluctuating with idle. Anything higher than 750 is probably not right (a vacuum leak possibly?). Much less than 550 is probably too much timing advance. Run the car to the redline in 3rd and 4th gears noting the highest readings you get

 

Running a standard 78mm pulley you should see 11psi if the charger is in good nick but a charger with a smaller pulley should make more than 11.6

 

EURO Hg(#'s of boost/vacuum)

 

200 - 23.7

400 - 17.8

600 - 11.9

800 - 5.9

1000 0 (Atmospheric pressure, charger is bypassed?)

1200 2.9 psi (You have a major boost leak)

1400 5.8 psi (Your charger is in very poor condition)

1600 8.7 psi (Your charger would benefit from new apex strips)

1800 11.6 psi (Good for stock pulley, needs new apex strips if 68mm pulley)

2000 14.5 psi (Good for 68mm pulley on stock charger)

2200 17.4 psi (Good for 68mm pulley on heavily ported charger)

 

i got an email back from her saying this:

Hi john,

 

I took it out but if I'm honest I didn't dare take it up to red in 4th. It's s bit bonkers because I'd be doing 100mph over.

 

But in 3rd it went to 820 and then again up to 1250 right near the red.

 

I'm sorry if this doesn't really help.

 

in all honesty, going over 100 is ridiculous just wondering if anyone has anything to say about this cause, the information in the email would suggest a 'major boost leak'. could getting it refurbed fix this or would it be well and truly shagged?

 

cheers, john

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Tin of worms.

 

This could be as simple as a worn/loose pipe, or as bad as a shagged charger.

 

Either way I would factor in a charger rebuild if it's never had one. But saying that you could buy the car, rip the charger apart to find it's had it. There are loads of G60's for sale - cheap enough which have had recent charger rebuilds.

 

Unless it's cheap enough I would personally avoid. It's been owned by someone who obviously doesn't know G60's so what else will it need? Just a thought.

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yeah if it was a worn pipe it wouldnt be too bad.

well its owned by tlc-g60 on this forum, i did a bit of research and i cant see many posts about bad things, just no charger rebuild and a bit of surface rust

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I'm no expert on G's.. But there are a few about for that amount of money that's had a charger re-built. But like all things, it's swings and roundabouts, it looks like a nice standard G.

 

That does seem like it's running low boost pressure, but like I say, without taking a look it could be anything, from as little as a £1 hose clip to a £700 charger. Just make sure you factor that in.

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Problem with that table is that by the time you hit the redline the boost pressure reading is being dumped back to return to prevent shock loading on the charger when it hits the rev limiter.

 

If the car is pulling ok through the rev range then it is more than likely a knackered pipe onto the MFA, worth checking out the MPG indicator to see if that is way out as that will givr you an idea.

 

That table relies on a completely standard car set-up, the addition of an RSR outlet changes those figures as it removes the restrictions in the boost system creating more CFM (flow) but less pressure.

 

My nugget makes well below those figures but that is down to the boost pipework and a chargecooler being fitted.

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If it's the charger and not a boost leak then you should see oil leaks inside the main boost output pipe that goes to the intercooler. I would go have a look at the car.. how far away is it?

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the car is 2 hours away, 4 hour round trip! so I was trying to get as much information. although the person has agreed to meet me halfway im going to have to go have a look see. cheers for all the advise by the way guys so i need to look for oil leaks around the charger?

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If your looking in the engine bay then on the right hand side of the charger there should be a black pipe section that goes from the charger down to the inter-cooler (located in the passenger wheel arch). Take a section of the pipe off near the charger end and rub a clean finger round inside. Should be relatively clean... If it's covered in oil then the charger is leaking oil and is likely in need of a service.

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Im going to see it wednesday so ill have a look at that. how does it come off? jubilee clip? or just a pull? anything else i should look out for, besides the obvious?

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2 jubilee clips. Take a screw driver with you as well as some rags to check oil etc. G60's like clean oil so knowing when the last oil change was would be beneficial too. Turn on the car and check for any noise coming from the car that shouldn't be there, Youtube is full of video's of broken chargers and good charges if you want to know what to listen out for. Then go for a spin, If the charger is not boosting or is leaking oil the performance will be very poor, it should be obvious.

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so take that off at the charger end? and if theres alot of oil the charger has seen many a better day? also, that is ALOT of rust! i hope the one i go to see doesnt look like that! haha

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so take that off at the charger end? and if theres alot of oil the charger has seen many a better day?

 

Yep if the car is on sale near another forum member as well you could be VERY nice and ask someone to go look at it for you. Save the road trip... I know a few folk on here that have said they would provide this service... I'm not saying you will though! lol

 

also, that is ALOT of rust! i hope the one i go to see doesnt look like that! haha

 

:( that's my car...

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I was thinking about doing that, but I would feel like i was putting somone out of their way, although there is another rado in cromer that i might need someone to look at, it has a pinking issue but is going cheap and i kinda wanna know why lol.

and sorry mate, i didnt mean to offend! is that part replaceable? or have you got a bit of welding to do?

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already fixed it :smug: needed a new panel though... no way that was going to be just welded...

[ATTACH=CONFIG]48065[/ATTACH]

 

the folk on here are generally nice people, and they can always say no.

 

http://the-corrado.net/showthread.php?51185-Where-to-find-your-nearest-corrado&highlight=nearest+corrado

there is a list of folk and where they're based. Every one on this list is a member and most have said they wouldn't mind checking out a corrado in their local area. Drop them a nice PM or start a new thread in wanted section and see if anyone can help.

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