Running 421-438 catcams in a high mileage standard engine.

[Fletcher]

I am due a cambelt change and have been thinking about fitting some cams, and ARP bolts. The engine is now on 139,200.

Thoughts?

 

[Ph1 Tom]

Maybe worth whipping the head off and checking the bores, doing new rings? Wouldn't be great fitting the cams and then having to do the rings later. Also worth doing the waterpump and depahser pulley I guess.

You could jump on the group buy to get the head ported and polished too! Then all the valve stem seals etc. will be fresh too.

 

[Dan@SJM]

Do a compression test, see how it is. Get the stem steals replaced as the cams are out IMO.

 

[Dan519]

On that mileage if the valve guides havn't got 2mm side to side play on the exhaust side I'll be shocked, running extra lift will disturb the stem seals enough for you to start using oil if you're not already. My engineers laughed at how bad the guide wear was on the last head I took in and that was on 100k. The valve stems themselves were worn on that one too.

 

[Andyman]

Basically just do a full rebuild on it lol

 

[Dan519]

Better off getting another engine, building it up gradually to spread the cost a little, and waiting for that one to pop to be honest

 

[Cup_Phil]

On that mileage if the valve guides havn't got 2mm side to side play on the exhaust side I'll be shocked, running extra lift will disturb the stem seals enough for you to start using oil if you're not already. My engineers laughed at how bad the guide wear was on the last head I took in and that was on 100k. The valve stems themselves were worn on that one too.

119k on my engine, 196bhp, compression is good across all 4 and in the last year it's never used a drop of oil

 

[Dan519]

but you've not changed your cams Phil, so you're totally out of context

 

[Keith185]

I'll be in a similar position soon,

Would a top end rebuild on it's own make sense following a successful compression/leak test?

Or would it not make much sense (cost and time wise) compared to a full rebuild?

Sorry if I'm hijacking the thread Fletcher.

 

[Cup_Phil]

but you've not changed your cams Phil, so you're totally out of context

You said after 100k they use oil and the valve guides are all worn. I think that's a bit of a sweeping statement. Mines done 60% of it's mileage sitting at 70 on long motorway runs and is absolutely fine.

But yes if you're going to fit new cams you might aswell replace them - I just don't agree that all 100k+ engines are worn and drinking oil

 

[Fletcher]

Thanks for the replies guys. Hijack away Keith

The long term plan is to eventually have it rebuilt/ forged and add some ITB's. so I might be better off waiting until then to add some 'hotter' cams. And for now just have the cambelt/ aux belt replaced.

 

[Tim.]

If you're going to just do a belt change, Fletcher, perhaps it would be worthwhile considering an RS2? You can sell it when you go for bodies and not lose a great deal of money, but you'll reap the benefits in the meantime. Just another option to mull over...

 

[Russ_16v]

With how well you have looked after it over the past 80, 000 odd thousand miles mate it wouldn't surprise me if it was still fine, but imo it comes down to budget, if you want to go decent power levels then getting another and rebuilding it isn't a bad idea as you know with a decent rebuild all the parts internally should be good.

Thats why I still have a spare ph1 engine, mine seems ok atm and has only done 45k but you can never be sure lol so will most likely be rebuilding the spare one in case the one in mine goes pop

 

[Fletcher]

If you're going to just do a belt change, Fletcher, perhaps it would be worthwhile considering an RS2? You can sell it when you go for bodies and not lose a great deal of money, but you'll reap the benefits in the meantime. Just another option to mull over...

I haven't rulled out a RS2 Tim, yours made great power. I Just prefer cams/ ITBs in general.

With how well you have looked after it over the past 80, 000 odd thousand miles mate it wouldn't surprise me if it was still fine, but imo it comes down to budget, if you want to go decent power levels then getting another and rebuilding it isn't a bad idea as you know with a decent rebuild all the parts internally should be good.

Thats why I still have a spare ph1 engine, mine seems ok atm and has only done 45k but you can never be sure lol so will most likely be rebuilding the spare one in case the one in mine goes pop

Yes Russ, it has been well serviced looked after. It made 171.5bhp at SSR just before it was SORN and it drinks no oil. The only problem I can see is a leaky rocker cover.

 

[davo172]

Cant see anyone fitting cams to an engine with that many miles on Tbh not a good idea IMO.

 

[Fletcher]

Cant see anyone fitting cams to an engine with that many miles on Tbh not a good idea IMO.

Why not? it made more power than lots of lower milegae cars when last at Surrey Rolling Road, and has no expense spared since buying it on 45k, 7.5 years ago.

 

[Cup_Phil]

Yep - nonsense

Mines had 2 oil changes every year and done 60-70k sitting at 70mph on the motorway. It makes 194bhp at 118k miles old
Compare it to a 40k engine that's just done lots of cold short journeys being ragged about and not serviced it's in very very good nick

 

[Russ_16v]

My black one made 193 bhp with just itb's - still had the cat in lol (145,000 miles)

 

[Fletcher]

Phil- Russ. Were both engines running standard internals?

 

[Russ_16v]

Yes mate, mine had never been apart - it had the itb's, and a yozza cat back exhaust, that was it.

I do get what he is saying, in that a lower mileage engine will be a better starting point, but with how cheap these engines are nowadays I wouldn't hesitate in sticking some cams and itb's on a high mileage engine and buying another in the mean time to refresh incase your original one goes bang.

I will make a point in saying it does depend on how the engine has been looked after - I know my black one spent it's first 80k on the motorway, then from 80 to 145k in my ownership it was never thrashed from cold, serviced every 6k and generally looked after so modding it I was happy with - if it feels good, rev happy, throttle response is good (feeling generally healthy) then i'd be happy.

FWI the compression on my black one at 130k was only 6-8 psi down on my current one which has covered 45k

 

[Cup_Phil]

Yep mines a bog standard engine - ITB's, 182 manifold, sports cat, oreca group n exhaust - 194bhp

Mine was owned by sir_dave and came with a folder full of receipts from opie oils. He used it for motorway commutes and did 2 full oil changes with filters/plugs etc... twice a year. It runs sweet as a nut

 

[Fletcher]

Yes mate, mine had never been apart - it had the itb's, and a yozza cat back exhaust, that was it.

I do get what he is saying, in that a lower mileage engine will be a better starting point, but with how cheap these engines are nowadays I wouldn't hesitate in sticking some cams and itb's on a high mileage engine and buying another in the mean time to refresh incase your original one goes bang.

I will make a point in saying it does depend on how the engine has been looked after - I know my black one spent it's first 80k on the motorway, then from 80 to 145k in my ownership it was never thrashed from cold, serviced every 6k and generally looked after so modding it I was happy with - if it feels good, rev happy, throttle response is good (feeling generally healthy) then i'd be happy.

FWI the compression on my black one at 130k was only 6-8 psi down on my current one which has covered 45k

Good stuff.

Yeah I can see what Davo is saying, in general a lower mileage engine should be 'healthier' just so many variables with engines.

I would have the engine all checked over before adding cams anyway mate.

 

[Russ_16v]

tbh there isn't a huge amount you can check - i'd compression test it, but as long as it pulls well and doesn't knock it's tits off (which last time i heard it it didn't lol) then i'd not worry too much.

You know the old saying if it ain't broke don't fix it, modify until it does lol

 

[Fletcher]

Yep mines a bog standard engine - ITB's, 182 manifold, sports cat, oreca group n exhaust - 194bhp

Mine was owned by sir_dave and came with a folder full of receipts from opie oils. He used it for motorway commutes and did 2 full oil changes with filters/plugs etc... twice a year. It runs sweet as a nut

Sounds similar to my 172. Previous owner did 45k of motorway miles, company car so well looked after.

tbh there isn't a huge amount you can check - i'd compression test it, but as long as it pulls well and doesn't knock it's tits off (which last time i heard it it didn't lol) then i'd not worry too much.

You know the old saying if it ain't broke don't fix it, modify until it does lol

Sounds about right Russ.

Last time I drove it was pulling like a train TBF.

 

[Russ_16v]

So in other words, pull your finger out and get some itbs :race: x

 

[Fletcher]

So in other words, pull your finger out and get some itbs :race: x

If only it was that easy mate

 

[Cub.]

Chop chop fletch old boy

 

[Dan519]

You said after 100k they use oil and the valve guides are all worn. I think that's a bit of a sweeping statement. Mines done 60% of it's mileage sitting at 70 on long motorway runs and is absolutely fine.

But yes if you're going to fit new cams you might aswell replace them - I just don't agree that all 100k+ engines are worn and drinking oil

no I absolutely did not! I said if you add cams it can disturb the stem seals and highlight other wear! Don't miss quote me!

the best way I can explain it is that mechanical parts have a memory. Things bed in. Guides can wear but the seals still work as they're running on the same part of the valve. Then you suddenly ask an old stem seal to run on a part of the valve stem thats never been touched before. The principle is exactly the same as running old shock absorbers on lowering springs, accelerated wear.

 

[Silent_Scone]

Better off getting another engine, building it up gradually to spread the cost a little, and waiting for that one to pop to be honest

^ Yerp


And yerp again. It's common sense, if somethings worked at a certain tolerance for 10 years and you then disturb it, it's not going to thank you for it.

 

[MG cup]

Do a compression test, see how it is. Get the stem steals replaced as the cams are out IMO.

Can the stem seals be done without the head off on these things? :S

 

[Chip-mk1]

Can the stem seals be done without the head off on these things? :S

Yes they can be done but its not really any massive amount less work than taking the head off TBH, as you still have to have the belts off and rocker off etc, at that point there really isnt much point in not lapping your valves in if you have got that far as its only such a tiny amount more work.
Ok so you add the price of a gasket, but its a small price to pay for decent valve seal again.

 

[Dan519]

can be done on most things with the right method. Fairly futile though, you can't check the guides and stems for wear while you're there

 

[MG cup]

Yes they can be done but its not really any less work than taking the head off TBH, as you still have to have the belts off and rocker off etc, at that point there really isnt much point in not lapping your valves in if you have got that far as its only such a tiny amount more work.

Never heard of this before on any car tbh.

I'm guessing, belts off, piston at TDC, smack the retainer with a socket until the collets come out, replace stem seal and struggle like feck to get the spring cap and collets back in?

 

[Chip-mk1]

Never heard of this before on any car tbh.

I'm guessing, belts off, piston at TDC, smack the retainer with a socket until the collets come out, replace stem seal and struggle like feck to get the spring cap and collets back in?

Kind of except you use a tool specifically designed to compress the spring in place, and you can use compressed air to hold the valve up (via plug hole) rather than bending it against the piston.
But I see no point on these particular engines, you have done such a big percentage of the work by the time you get that far you may as well lap the valves in and at the same time of course check to see if there is any other remedial work required such as guides etc.

 

[MG cup]

Kind of except you use a tool specifically designed to compress the spring in place, and you can use compressed air to hold the valve up (via plug hole) rather than bending it against the piston.
But I see no point on these particular engines, you have done such a big percentage of the work by the time you get that far you may as well lap the valves in and at the same time of course check to see if there is any other remedial work required such as guides etc.

Every days a schools day. I had a quick google, are all these valve compressor tools engine specific?

 

[Chip-mk1]

Every days a schools day. I had a quick google, are all these valve compressor tools engine specific?

Not engine specific, but you might need to make up different bracket etc, so they arent totally universal either.

 

[p@blo]

What's the general consensus for sourcing valve guides?

 

[Chip-mk1]

What's the general consensus for sourcing valve guides?

I try and stick to colsibro type ones for performance builds.

 

[john182rs]

OK, going to throw a spanner in the works now, at what point is it not good to add cams to an engine? Mines just hit 93K and was thinking of cambelts done at 100k with cams too.

 

[Chip-mk1]

OK, going to throw a spanner in the works now, at what point is it not good to add cams to an engine? Mines just hit 93K and was thinking of cambelts done at 100k with cams too.

Depends on the condition of your stem seals which is more about age than miles.
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