All Things Mk5 > R-Tech Zone

Stage 2 or 2+ ???

<< < (2/3) > >>

griff30:
Cheers fellas. That’s a lot of food for thought...    Got a Helix clutch already so thats not a problem (standard went straight away at stage 1). Most of these comments tend to make me think I don’t want to go the full way with it... 

 Colesy - why stick with standard airbox? Does a CAI (eg. Revo) mess up the response or something? Ive heard you can lose some low end which I wasn’t keen on but could live with if its just a bit. 

Dave - yep the BCS is ace. Nice deep sound when pootling around, but not intrusive at all. Then gives a good roar when you plant it.

Will prob just do IC, possibly intake then ask RTECH to do a nice driveable map when i get the inlet clean done. Spend the money saved on tyres and maybe some handling mods.  Thanks again.

colesey:
Griff, it’s the Bernouli effect - the same mass of air will travel more slowly through a larger pipe. Try have a read of Pudding’s posts over last few months where he has compared stock v Revo v VWR intakes and wasn’t overly impressed by the aftermarket options. Is best you have a chat with Niki about what he can achieve for your driving style and tastes.

pudding:
What /\ he said. 

All engines have a peak volumetric efficiency, I.e. one rpm where everything marries up perfectly for the strongest torque.   OEM engine designers use specific cam profiles, turbo sizing, exhaust and intake diameters, airbox size, plenum volume, throttle body size etc to make every other rpm around that VE point the best compromise possible.   They also tailor the gearing to suit the torque curve i.e. Honda use very short gearing to increase wheel torque to overcome the engine's low flywheel torque....and so on, and so forth.

The best compromise usually means keeping the gas speed up, both into and out of the engine, which means deliberate restrictions.....which appear counter intuitive to enthusiasts and less experienced tuners.  As soon as you change intake diameter, exhaust diameter, cam profiles, turbo size etc you move that peak torque zone further up the revs, and one thing I have definitely noticed with these bath sponge on a pipe filters is the reduced gas speed at <1750rpm causes a slower, rougher idle, incorrect MAF readings, and a noticeable flattening of the throttle response at low revs.

So to summarise all of that waffle into one easy to digest sentence - aftermarket intakes are good for one thing only: increasing power past 5000rpm.

Claims of 40hp from Revo for their intake (with a 2+ tune) and 25hp+ from Racingline are grossly exaggerated in my opinion, and experience, so take the marketing with a dose of table salt.

griff30:
Yeah that all makes sense. My understanding of engines/tuning is pretty decent from back in the day, but Ive only learnt anything about turbos since having the golf. I had thought the benefit of the intake would be felt in the midrange as well. If its all over 5k then wont be any benefit most of the time... Ill go and read up on all your posts about intakes later.   
 Thanks thats been a real help and told me what I needed to know. I think you get caught up in the whole process and want to keep making incremental changes, but sometimes they’re not worth it. Power is ace, but Ive said for a while I get more pleasure from the suspension/handling improvements Ive made to the car really. Before, the engine was just overwhelming the car, which doesn’t really feel good. Now its a pretty good balance, and plenty fast enough.
 I think Ill still upgrade the intercooler though - just feel that I want to as its a weak link.

pudding:
Below 5000rpm the engine feels like it's breathing better, but it's probably not a measurable increase on the dyno.  Just a butt dyno feeling thing.   There is real gains at the top end with a half decent intake though, usually in the order of 20-25hp with a good tune.  It does also depend how healthy the engine is, what state the injectors are in, what state the turbo is in etc etc.   Like you say, if you're not regularly blasting it past 5000rpm (virtually impossible where I live) then intakes shouldn't be top of the priority list.  I have tried a few just for the sake of experimentation but I always end up putting the standard one back on because as a daily driver, the area 'under the curve' is more important to me.

100% agree with you on the suspension and handling mods  :happy2:

If you arm yourself with VCDS, you can do some logging to see how badly your current intercooler is heat soaking.   The standard one starts to get at the top end fairly quickly.  An S3 one improves things a good chunk because the core is 40% larger in cross sectional area, without being so big it increases lag to a noticeable degree.  Not too expensive either.  Around £300 from the dealer, vs twice that, minimum, for a decent aftermarket one.

Navigation

[0] Message Index

[#] Next page

[*] Previous page