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Jim

Jim's 1995 Corrado VR6

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I thought INA were basically OE?

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No one ever seems to replace the valve springs, maybe this could also be the cause of valve train clatter?

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Have always also wondered the same, Dox.

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Have always also wondered the same, Dox.

 

Hmmm - not a bad point as they always advise they should be upgraded with cams and you did have the cams fitted for a bit.

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Have you ever replaced the exhaust manifold? Just thinking out the box a little but maybe its that, some sort of resonant frequency from the exhaust gasses on that particular car.

 

All my Vr's have been noisey to an extent, its just the way they are.

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Exhaust manifold has never been touched so far as I know, apart from having been removed from the car several times!

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Well the 20+ year old springs must have lost some tension in that time, a recon head will have had the seats recut allowing the valve to seat a little lower and the now weaker springs aren't as compressed as much as before either (a non hydro head would need thinner shims to compensate for the valve seat cut).

 

I have INA tappets bought from an ebay seller, used tappets of unknown origin still in a head in the garage loft and access to accurate calibrated scale to within a gram.

 

It would be easy to compare old and new springs but I don't currently have new springs

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Hmmm - not a bad point as they always advise they should be upgraded with cams and you did have the cams fitted for a bit.

 

It's been a recurring theme that those folks who've had Schimmel cams fitted, I think, seem to encounter this noise. I wonder if they somehow wear the valve springs in a certain way?

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It's been a recurring theme that those folks who've had Schimmel cams fitted, I think, seem to encounter this noise. I wonder if they somehow wear the valve springs in a certain way?

 

A performance cam will lift the valve higher and open it for longer so the valve returns with a little more force due to the extra compression of the spring (because of the extra lift) and more abruptly due to the longer duration of the lobe.

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Very nice, but it still needs the guides pressing in, reamed and the seats truing.

 

There's a Hungarian guy on FB doing heads for £500ish - Schubert Levente or something similar

 

https://www.facebook.com/schubert.levente?fref=ts

 

He sometimes posts VR6 heads on VR6OC FB page

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Exhaust manifold has never been touched so far as I know, apart from having been removed from the car several times!

 

You will probably know the answer by now, but I was also going to say exhaust manifold. Had a cast factory one crack on my G60 - made it sound like tappets were worn. Replacement sorted the issue out.

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Is there any obvious way to identify a cracked exhaust manifold aside from visual inspection? It does seem interesting that it gets worse once warm which could suggest the heating up process causes any splits to become more apparent.

 

Unfortunately today's trip didn't really yield any answers. The chaps at Stealth say it's just VR6 noises, and that there's not much can be done to improve it. At the end of the day they know more about the VR6 than I can or will ever hope to know, but I can't deny that I'm feeling pretty deflated inside. I just don't ever remember it being this obvious - and indeed I don't recall hearing many other VR's that sound this way but I just wonder if I'm going crazy now!

 

I went and stuck about 80 miles on it last night and the ticking was so obtrusive it was quite audible in the cabin even over the radio when I was cruising at 70MPH.

 

Either way they decided to drop the oil and make sure everything looked good (it was pristine). I have been militant about running in the engine according to their instructions though.

 

It turns out the head was swapped during my rebuild as original head was so clapped out, it wasn't really going to be feasible to rebuild it! So that rules out the noise persisting across rebuilds as being related to the head, given that it's a replacement one!

 

Took it for an MOT straight after as that was overdue and got through with only a couple of small advisories so that's something.

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I think noise should decrease if it's manifold related Jim, as the metal expands and affectively fills the Crack. Get a single ply of bog roll or tissue, and from stone cold so you don't burn yourself, run it around the manifold and gasket. Any cracks should noticeably blow the tissue.

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I think noise should decrease if it's manifold related Jim, as the metal expands and affectively fills the Crack.

 

That's what I would have thought too mate.. just desperately searching for answers I guess.

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Fair enough mate. I can't think of anything else it could be to be honest. The engine is obviously in perfect shape from top to bottom, so maybe have a look around the rear engine mount or Throttle body area to see if there is anything rattling. I know you sometimes hear things that aren't really there when it's on your mind, but you shouldn't be hearing it at speed.

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It doesn't sound like a manifold / exhaust problem , it would have new gaskets fitted and you would think that any cracks would have been spotted during the engine rebuild and as said manifold cracks get quieter as the engine warms up anyway .

The fact you can hear it at 70 mph with the radio on doesn't sound right though ..

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Yep - all foam in tact. The fuse tray cover is currently not installed though - I'm wondering if that is letting through more sound than would be normal!?

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Yes it will do mines off at the mo and its noticable lounder

 

There should also be two pieces of thick felt down the side of the dash either side , i noticed these let alot of engine noise in

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Man I feel for you Jim . What a pain ! . You can hear it at 70 , with the radio on ?! Would a stethoscope be of any use , to pin pointing it ? . I know stealth have checked and they are experts , I'm just thinking of using something to amplify the ticking .

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