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Mods to Classic air filter and pipework
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Old 17 Feb 2011, 03:07 PM   #1 (permalink)
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Mods to Classic air filter and pipework

Hi, Guys

I read somewhere that to improve the intake of air on Classic turbos (probably all Scoobies), it's an idea to upgrade some of the intake pipework to silicone ones as well as fitting a free flow panel filter.

Mention was made of replacing the "intake pipe" with a silicone one and that with the panel filter, this could give as much as 10bhp extra.

Which pipe is the "intake pipe" please ? Is it the hard rubber one with lots of rings around it, from air filter box to engine or is it something else ? (Because I think removing the intercooler was also mentioned).

To replace this hard rubber one (about 76mm diameter) costs around 60+. Yet I cannot imagine any great benefit in a silicone version that'd justify this expense.

So, which is the most beneficial pipe to replace ?

Has anybody any thoughts, please ?
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Old 17 Feb 2011, 05:10 PM   #2 (permalink)
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Re: Mods to Classic air filter and pipework

Don't think you would gain 10bhp. The air filter will help. The pipe looks well and will help but not significantly IMO
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Old 18 Feb 2011, 08:31 AM   #3 (permalink)
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Re: Mods to Classic air filter and pipework

Thanks, Shambles. If there is anything that would assist with other small increases, perhaps you'd let me know but I'm very grateful for your thoughts.
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Old 18 Feb 2011, 12:33 PM   #4 (permalink)
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Re: Mods to Classic air filter and pipework

wont make that much difference if any, cold airfeeds have been known to give extra 10bhp, but also requires mapping
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Old 18 Feb 2011, 02:53 PM   #5 (permalink)
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Re: Mods to Classic air filter and pipework

Thanks very much Tidgy. Always glad for your thoughts. And I have found some of your other posts very informative.

Following your advice a couple of weeks ago, the remap will be the last stage after whatever other upgrades are fitted. Funds are a bit tight but am currently considering any further small power increases over and above panel filter, decat downpipe and remap. Changing to Shell V Power seems to have made a noticeable difference.

Once I've gone through all the other affordable possibilities, then the work will begin.
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Old 18 Feb 2011, 08:20 PM   #6 (permalink)
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Re: Mods to Classic air filter and pipework

would your search have been referring to the resinator??? not quite sure of the exact set up (both of mine have always been fitted with induction kit), but between your air box and the inlet manifold there should be a resinator box, removing this and replacing it with a straight through pipe increases the air flow.
i'm no mechanic, but it's just a thought??!!
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Old 18 Feb 2011, 09:54 PM   #7 (permalink)
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Re: Mods to Classic air filter and pipework

What year is your car what model and what mods have you got already
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Old 18 Feb 2011, 10:02 PM   #8 (permalink)
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Re: Mods to Classic air filter and pipework

get some pics up, probably the easiest way to get advice!

Last edited by cokes; 18 Feb 2011 at 10:05 PM.
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Old 19 Feb 2011, 10:58 AM   #9 (permalink)
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Re: Mods to Classic air filter and pipework

Thanks, Guys. I'm grateful for your thoughts.

I didn't know there was a resonator between the air box and inlet manifold. Thanks to Shambles' advice, I now have the exploded diagrams so I'll have a look. If I've got a resonator there, then removing it might well make a difference. I'm not a mechanic but am keen to learn the theory.

Presently, it's a standard Year 2000 Classic turbo. Previously run on 95 RON fuel but now using Shell V Power. Even that made a difference. Am planning a 3 inch decat downpipe, unsure about replacing the standard centre section as it's got a resonator (which I think quietens the exhaust a little - I don't want to wake the neighbours when I go out), free flow panel filter and a re-map. The standard rear exhaust box was new about a year ago so am uncertain about any gains from a single larger bore tail pipe.

I thought I'd read somewhere that changing the induction pipe (now found to be under the intercooler) for a silicone one would help, but advice so far is that it wouldn't really make any noticable difference.

As to brakes, the fronts are four pot and two pot on the rear so am wondering about changing the pads to a harder set - and when the disks wear out (late braking), replacing them with spiral cut, maybe drilled ones. For my sort of driving (roads only), I don't know that bracing struts across the car would benefit much, even though somebody said that improved performance also comes from better handling. Good logic. Sounds good to me. I'm keen on that and driving technique (still have a lot to learn) but it seems to me that efficiency is key.

Funds are a bit tight but if there are any other ways of squeezing a little more power or acceleration, any thoughts or advice would be very gratefully received.
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Old 19 Feb 2011, 12:35 PM   #10 (permalink)
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Re: Mods to Classic air filter and pipework

Decat and remap will make the biggest difference. Not sure if the 2000 uk turbo can be remapped without changing the ecu
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Old 19 Feb 2011, 01:46 PM   #11 (permalink)
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Re: Mods to Classic air filter and pipework

Hi, Shambles

Thanks for your post. My understanding (from VeySport who I plan to get to do the "intelligent" work) is that an Ecutech re-map would be readily possible. I'd given the VIN and year of the car so they would know what they'd be working on.

If it turns out that you're right then a new ecu will be needed. Having become keen to make it go quicker, I'm not about to give up yet !

Am also now thinking of lightened pullies. As you say, the decat and remap will be the greatest improvements but from the difference I've noticed between 95 RON fuel and Shell V Power, excitement is barely the word !

While trying not to expect too much, I cannot wait until getting all this work done. Still open to ideas, however !
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Old 19 Feb 2011, 03:50 PM   #12 (permalink)
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Re: Mods to Classic air filter and pipework

Perform an ecu reset after changing from 95 to 99 if you haven't already done it
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Old 19 Feb 2011, 04:18 PM   #13 (permalink)
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Re: Mods to Classic air filter and pipework

Thanks for the advice. I had planned the re-map after all the other work was done. Will it cause any engine damage if it waits for a short while ?
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Old 19 Feb 2011, 07:26 PM   #14 (permalink)
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Re: Mods to Classic air filter and pipework

It makes sense to do all the mods and then do the remap. Personally I would fit them all and have the remap booked a few days later - so if you run into trouble fitting the mods you will have time to sort it.
I wouldn't drive the car personally until mapping was done. If you really have to keep it off the boost and drive it like a nun or damage will likely occur.
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Old 20 Feb 2011, 09:44 AM   #15 (permalink)
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Re: Mods to Classic air filter and pipework

Thanks, Shambles. I'm very grateful for the advice.

In that case - as I have a tank full of V Power (and with my wayward right foot, driving like a nun would be asking the impossible) - I better re-plan my timescales.

What damage is likely ? Destroying the the cat ?
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