Carbon clean? Bang for buck?

[jonytek]

I have just got my new RS4 and am trying to decide what to do first. Ive got the wheels booked in for a colour change to a darker grey, once this cosmetic change is complete I am thinking about trying to get a few more horsies out of the engine. Im thinking a health check and probably (if I need it) carbon clean from MRC.

Is this likely to give me the biggest bang for buck? Where have others started this expensive rabbit hole? The car is stock atm.

[MikeFish]

Waste of money if you aak me. It will feel good when done but will quickly need doing again. I'd rather soend the money of an MRC stage 2 remap that you will benefit from forever.

[TobyRS4]

You've entered into a political whirlpool on Carbon Cleans.

Some think its a waste of money as the carbon will return, others swear by them.

I sit somewhere in the middle, my car has 75k and has never had a carbon clean and il probably do no more than 2-3k per year in it.

So for me to remove 10 years and 75k's worth of carbon is always a good idea, so i had it done, however bang for buck the stage 2 is best value but then again a stage 2 will give you better bang for buck after a carbon clean, and then back to the argument that even after this the carbon will build up again.

I suppose it comes down to how much your prepared to spend on the car or even want to spend on the car

[MikeFish]

I disagre, why remap your car after a carbon clean? It will be sludged up again pretty soon so I think you are better off having it mapped when dirty as that is how it will spend most of its life.

[irn_bru_ce]

Same goes for the air filter , just leave the original one in, don't bother replacing it or cleaning it, it'll simply get dirty again, you'll lose performance, but who's counting

[MikeFish]

Same goes for the air filter , just leave the original one in, don't bother replacing it or cleaning it, it'll simply get dirty again, you'll lose performance, but who's counting

Air filter is easy and cheap to replace. And gets done on annual service. Hardly the same.
If they could carbon clean for £30 and do it in the same few hours it takes to service then I'd say go for it.

[PetrolDave]

Waste of money if you aak me. It will feel good when done but will quickly need doing again.

I disagre, why remap your car after a carbon clean? It will be sludged up again pretty soon so I think you are better off having it mapped when dirty as that is how it will spend most of its life.

+1 on both those points

After 5k miles the carbon will be back to near as dammit the same extent, so it makes no sense at all to me.

Carbon buildup has a natural maximum limit (once the carbon gets far enough out into the manifold where the airflow is higher it can't buildup any more) so surely it makes most sense to get the best you can out the engine when it is in it's long term stable state with carbon buildup?

Unless of course money is no object and you can afford the cost and inconvenience of a carbon buildup every 5k miles?

[TobyRS4]

I disagre, why removed your car after a carbon clean? It will be sludged up again pretty soon so I think you are better off having it mapped when dirty as that is how it will spend most of its life.

Bang for buck wise after a carbon clean will see the greater gains was all i was saying, i'm not doubting the carbon build up however to note 3 points:

1. A car will not build up the same amount of carbon in 5k as it will in 75k.
2. Doing 2-3k per year or low miles the build up will be slow, if you have every intention of continuing with carbon cleaning then why not if the cost isnt an object as this is the way the engine will more often be?
3. Doing 20k per year, carbon cleaning will be I agree a futile effort as the map on top of a carbon clean wont be of benefit as its not the way the engine will spend its life, you may as well have it mapped and not carbon clean.

As I said its purely objectional, however I do know quite a few users have seen issues due to carbon buildup, so as i was saying its a big circle and your vehicle usage affects the relevance of the carbon clean in combination with how much you want to spend on the vehicle ongoing maintenance.

[PetrolDave]

1. A car will not build up the same amount of carbon in 5k as it will in 75k.

Oh yes it will, that's been proven on here many times over the last 10 years.

2. Doing 2-3k per year or low miles the build up will be slow, if you have every intention of continuing with carbon cleaning then why not if the cost isnt an object as this is the way the engine will more often be?

Doing that sort of low mileage usually implies more low rpm running and less "Italian tuning" (unless you use lots of rpm before the engine is fully warm, which is a seriously bad idea), so carbon buildup will be at the highest rate in this scenario.

3. Doing 20k per year, carbon cleaning will be I agree a futile effort as the map on top of a carbon clean wont be of benefit as its not the way the engine will spend its life, you may as well have it mapped and not carbon clean.

Since carbon buildup reaches a maximum after approx. 5k miles you don't need to do anywhere near as much as 20k miles per year for carbon cleaning to be futile, even 5k per year will be enough to reach the point of it being futile.

[TobyRS4]

The quantity of build up and the age of the build up are two different things altogether in terms of the material disposition and adhesion.

Vehicle use allowing the vehicle to get up to temperature at idle, followed by fast driving isn't this scenario.

And agreed on the latter yet again as per my original post Carbon Cleaning is personal preference and again I sit on the fence, liken it as you will to showering in the morning you know you'll be dirty again by the end of the day but it didn't stop you showering in the first place did it?

[TobyRS4]

and yet again the carbon clean debate goes on...............

[PetrolDave]

The quantity of build up and the age of the build up are two different things altogether in terms of the material disposition and adhesion.

Which is almost an argument NOT to carbon clean - once the carbon has built up to it's maximum extent (after 5k miles) and gets hardened with age and heat then it's less likely to become dislogded into the cylinder (and potentially cause damage) than carbon that keeps building up from zero.

Vehicle use allowing the vehicle to get up to temperature at idle, followed by fast driving isn't this scenario.

Agreed, but "Italian tuning" has been shown by RS4 owners to be beneficial to slowing down the rate of buildup in cars that are not regularly used.

Carbon Cleaning is personal preference and again I sit on the fence

Agreed it's a personal preference, personally I never sit on the fence as it's too painful

[TobyRS4]

If it then hardens with age and heat wouldn't it then if dislodged be more likely to cause damage?

haha I love the backwards and forwards with Carbon Cleaning I'm just being devils advocate, so anyway back to the OP..... I guess the ball is in your court based on the above.

However the overwhelming truth is that its now almost become expected by the uninformed or pro carbon cleaners to be done which in turn is forcing some peoples hands to then in turn have it done.

[jonytek]

Well I didn't realise that this was such a hot topic around here. The reason that I was thinkimg about the clean first was for a couple of reasons. Firstly, it wouldn't have any impact on my insurance and secondly from what I've seen it can be a huge performance gain. Although with this gain only being short lived it does seem to be a bit of a waste of money. I don't really want to have to be doing this each year.

I think the first stop for me is going to be a run on the dyno for a full health check up and a good chat with the guys at MRC, from there I can look another option such as the remap, maybe an exhaust.

Out of interest what sort of prices are uk insurance companies charging for the stage 2?

[TobyRS4]

it sure is, just whatever you do don't ask next about tyres......

You cant go too far wrong having it dyno health checked with MRC it will give you the peace of mind that you have a good base to work with.

Mine didn't charge me just mentioned they would note on the policy which made me kind of wonder why id bothered.