Noisy Cologne 2.8 since fitting Piper BP270 camshaft

[Kitchski]

Hi all,

Have posted in the relevant TVR forum but thought maybe I'd try my luck in here. I recently fitted a Piper BP270 (mild/fast road, nothing aggressive) camshaft to my TVR S1. It was fitted during a time where the car was extensively overhauled.

Below is a copy of the post I made in the TVR forum:

[quote]So since I got the S1 back on the road, I've noticed the 2.8 engine is on the tappy side. It runs fine, pulls fine....seems fine. But it's noisy. My plan is to delve deeper over the upcoming winter, but on the phone to a well-respected engine builder the other day it popped up in conversation. As soon as I said I'd fitted a Piper BP270 camshaft to the Cologne, he said that's the issue as they're noisy cams due to the way they drop-off lift. Admittedly, the noise isn't actually tappets (checked them and they're fine) and when fitting the cam it also had matching springs, new lifters etc and was bedded in correctly. It's just this noise!
I've also fitted a solid alloy timing gear, but was assured these are no noisier than the originals, and that it's the steel ones that don't sound great. Oil flow to the head is good (heads were dip-cleaned and rebuilt) and the engine's only done 68k miles.

Wondered if anyone else in the 2.8 world had been down this road before I go ripping the cam out to put a standard one back in (the BP270 gave no power gains, incidentally).

[/quote]


Here is a link to the current live thread:

http://www.pistonheads.com/gassing/topic.asp?h=0&a...

Thanks for your time

[Pumaracing]

Kitchski said:

It was fitted during a time where the car was extensively overhauled.

Then it strikes me that the assumption that all the noise is due solely to the cam might be erroneous.

[Kitchski]

Pumaracing said:

Then it strikes me that the assumption that all the noise is due solely to the cam might be erroneous.

I agree, I kinda think the same. The only link is that a well-respected Cologne specialist mentioned that those cams specifically can cause that issue. The only reasons I haven't taken this at face value (though I appreciate he's more clued than I in the ways of the Cologne) is firstly that I've never seen or heard of that happening before on any engine (though everyday's a school day of course), and secondly I can't quite get my head around the logic of it. Surely a valve clearance is a valve clearance, and the valve spring would keep enough weight on the lifter (solid lifters in this) to prevent a rattle caused by the rapidly changing contact patterns?

When I say the rest of the car went through an overhaul, it was the chassis. The engine received a light smattering of work; heads off, cleaned with renewed seals, new gaskets and seals all round the block etc. It was cleaned and painted too, but I can't think of anything else that could affect this issue other than the cam, the fitting of it and the disturbance of things like rocker shafts etc.

[Pumaracing]

Kitchski said:

The only link is that a well-respected Cologne specialist mentioned that those cams specifically can cause that issue.

I was watching QI the other day. I learned that there are in fact many thousands of sphincters in the human body rather than just the few obvious ones we might first think of. It seems that the blood vessels also have them.

The one that "engine specialists" talk out of is undoubtedly the largest though. Camshaft lobe profiles pushed to the absolute bitter edge in terms of accelerations and tappet velocity such as the ones in Top Fuel dragsters which are only expected to last a single pass down a 1/4 mile strip could well be expected to be a tad more noisy than stock. Mild road cams however that are expected to last the life of the engine are not!

Whatever the noise is I can guarantee two things. It's a sign of something being unhappy with its lot in the general scheme of things and it won't get better on its own.

[one eyed mick]

WAs the cam bedded correctly ? on rebuild I know that the 2 top [?] manufacturers insist on correct procedure for this

[PaulKemp]

Check valve springs for binding
It's a long shot as if they are binding and you have driven for some miles I would expect a breakage but you've got to start somewhere

[PaulKemp]

Check valve springs for binding
It's a long shot as if they are binding and you have driven for some miles I would expect a breakage but you've got to start somewhere

[Pumaracing]

They say that free advice is worth what you paid for it so I guess you don't eau de Cologne specialist anything.

[Steve_D]

one eyed mick said:

WAs the cam bedded correctly ? on rebuild I know that the 2 top [?] manufacturers insist on correct procedure for this

Kitchski has been busy so may not have seen these replies so I will add that the cam was run in at 2500 for 20 mins. We also run our rolling road fan up front for extra cooling.

Steve

[Kitchski]

PaulKemp said:

Check valve springs for binding
It's a long shot as if they are binding and you have driven for some miles I would expect a breakage but you've got to start somewhere

It's one thing I haven't checked, but new springs were supplied with the kit, and it's not like it's an aggressive cam or anything.

[Auntieroll]

The camshaft profile is, as PumaRacing rightly says, unlikely to be the cause if all the clearances have been set correctly.
The alloy timing gear however.......
Whoever told you that an alloy timing gear would be no noisier than the OEM fibre toothed item was IME being "economical with the truth".Many years ago I fitted the same aftermarket combination for a customer and the increase in noise was very noticeable.
Ask yourself why Ford would spend more money fitting a composite cam gear if it wasn't required, to get a metal toothed timing gear set up meshing correctly requires individual selective assembly, something that costs money, the (eventually) self destructing fibre set up allows a "fudge factor" which enables a one size fits all (ie cheap!) timing gear set up to be used
It is just possible that the alloy gear will bed in a bit and get quieter but I wouldn't hold your breath!

Edited by Auntieroll on Monday 29th June 18:54

[Mr2Mike]

Pumaracing said:

They say that free advice is worth what you paid for it so I guess you don't eau de Cologne specialist anything.

The suspicious git within me wonders if the aftermarket timing gear was machined correctly so that the retaining bolt clamps it solidly against the end of the cam. If the gear isn't being clamped correctly, the woodruff key and key way will be taking a lot of abuse...

[Kitchski]

Auntieroll said:

The camshaft profile is, as PumaRacing rightly says, unlikely to be the cause if all the clearances have been set correctly.
The alloy timing gear however.......
Whoever told you that an alloy timing gear would be no noisier than the OEM fibre toothed item was IME being "economical with the truth".Many years ago I fitted the same aftermarket combination for a customer and the increase in noise was very noticeable.
Ask yourself why Ford would spend more money fitting a composite cam gear if it wasn't required, to get a metal toothed timing gear set up meshing correctly requires individual selective assembly, something that costs money, the (eventually) self destructing fibre set up allows a "fudge factor" which enables a one size fits all (ie cheap!) timing gear set up to be used
It is just possible that the alloy gear will bed in a bit and get quieter but I wouldn't hold your breath!

Edited by Auntieroll on Monday 29th June 18:54

You make a fair point, do you recall what sort of noise it made? Most people I've spoken to said the steel gear creates a whine, almost like a supercharger. I might be able to get my hands on a fibre gear if I'm lucky.

[Kitchski]

Mr2Mike said:

The suspicious git within me wonders if the aftermarket timing gear was machined correctly so that the retaining bolt clamps it solidly against the end of the cam. If the gear isn't being clamped correctly, the woodruff key and key way will be taking a lot of abuse...

Again, fair point, though we were supplied run-out tolerances and it was well within limits on the DTI. Didn't measure the depth of the bore where it posts onto the end of the cam compared with the old one, which I would do again in hindsight.

I suppose the thing to do here is find a fibre gear, pull the alloy one off and then run it up with the cover bodged back on. If the noise goes, I'll then refit it properly. If it remains, crack on and remove the cam.

[Auntieroll]

As far as I recall (it was 20 + years ago!) There was a chatter/rattle at certain speeds, along with a whine, I would definitely think long and hard about fitting a fibre gear permanently, they were notorious for failures,with the standard cam there was no problem with valve to piston clearances ie "non interference", with the 270 cam I wouldn't know, the problem was with the fragments of the gear teeth which used to get absolutely everywhere inside the crankcase ,they took ages to locate and clear out!! and that was one that failed on start up!
I would be interested to see if swapping the camwheels cured the noise but if there were no other problems with the aftermarket one I would refit the alloy one after the experiment for safety's sake.

In defence of the manufacturers the gear cutting would have to err on the "slack"(safe) side as having the tooth engagement either too small or toothbound would not be conducive to longevity. The centre to centre production tolerances achievable in those days would probably be quite wide in gearcutting terms, hence the fibre gear useage.HTH.

[Kitchski]

Auntieroll said:

As far as I recall (it was 20 + years ago!) There was a chatter/rattle at certain speeds, along with a whine, I would definitely think long and hard about fitting a fibre gear permanently, they were notorious for failures,with the standard cam there was no problem with valve to piston clearances ie "non interference", with the 270 cam I wouldn't know, the problem was with the fragments of the gear teeth which used to get absolutely everywhere inside the crankcase ,they took ages to locate and clear out!! and that was one that failed on start up!
I would be interested to see if swapping the camwheels cured the noise but if there were no other problems with the aftermarket one I would refit the alloy one after the experiment for safety's sake.

In defence of the manufacturers the gear cutting would have to err on the "slack"(safe) side as having the tooth engagement either too small or toothbound would not be conducive to longevity. The centre to centre production tolerances achievable in those days would probably be quite wide in gearcutting terms, hence the fibre gear useage.HTH.

It does help, thanks. The issue with the fibre wheel is that I keep hearing (from the older gen; I'm slightly younger!) that the issue was always with the Essex wheels, not the Cologne. The only person who's ever suggested the Cologne ones fail too was the guy selling the alloy wheels
I can't reuse my old one as I dropped it, hence the new one. It didn't visibly fracture or break, but I didn't think it wise to chance it. I might be able to source another one though. If it gets rid of the noise I'd be happy to 'chance' leaving it in there as I know plenty of others running the same engine and have never heard and seen of an issue. Besides which, it does 1000 miles a year if it's lucky!

Cheers

[AW111]

Auntieroll said:

As far as I recall (it was 20 + years ago!) There was a chatter/rattle at certain speeds, along with a whine, I would definitely think long and hard about fitting a fibre gear permanently, they were notorious for failures,with the standard cam there was no problem with valve to piston clearances ie "non interference", with the 270 cam I wouldn't know, the problem was with the fragments of the gear teeth which used to get absolutely everywhere inside the crankcase ,they took ages to locate and clear out!! and that was one that failed on start up!
I would be interested to see if swapping the camwheels cured the noise but if there were no other problems with the aftermarket one I would refit the alloy one after the experiment for safety's sake.

In defence of the manufacturers the gear cutting would have to err on the "slack"(safe) side as having the tooth engagement either too small or toothbound would not be conducive to longevity. The centre to centre production tolerances achievable in those days would probably be quite wide in gearcutting terms, hence the fibre gear useage.HTH.

Worth checking for lash, I suppose : camshafts are a really irregular load, so any freeplay in the gears would probably have a noticeable effect.

[Kitchski]

I think I'm resigned to the fact I need to swap out the camshaft gears and try it. If the noise remains, I'll go one further and change the cam (seeing as it'll already largely be in bits, though I personally doubt the cam is the cause). The noise wrecks any enjoyment you might have had driving the car. It just sounds fked!