GolfGTIforum.co.uk
Model specific boards => Golf mk2 => Topic started by: Jon16 on 08 November 2003, 15:11
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Hi Everyone! I have a 1990 16v which goes very well (even better after recent service) but I still yearn for the sort of poke my old BMW 328i Sport had! (a little optimistic I'll admit!) The car has a full stainless Scorpion exhaust (well all except the manifold) and a K&N filter (in the airbox). My mechanic said the getting a performance exhaust manifold will make quite a big difference, but which one? Also is there anything else that you recommend that doesn't cost the earth?! THANKS!!!
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Have you drilled the airbox ? also try some fast road cams.
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Ive herd that drilling the airbox is a waste of time?
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drilling the airbox is NOT tuning your car - it does little if anything to aid performance.
It just makes induction more audible.
A new air filter is a start but,
would only really be 'performace' if you added a long branch exhaust.
New longer duration cams would be a waste of time - unless you have ported and flowed your head.
Remember:
It's all about getting the fuel and air mixture in and out as quickly and as un obstructed as possible.
If you're feeling flush - why not change the bottom end for a 2litre item
Then to complete the package why not fit a new Management system (Emerald are good) and maybe a quaife box with LSD (assuming you've uprated your suspension).
You can forget all about your 3series chugger after that
;D
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Drilling the front and side(not engine side) on old k-jet cars makes a big difference if combined with a sports air filter. This is because stock air boxes are very restrictive (to keep noise levels down), opening it up stops the depression occurring in the airbox, hence much better throttle response and a little bit of extra power.
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I don't think you emphasized the word 'little' enough
It merely makes your car sound louder
like drilling your back box on your mk2 escort back in the day -
if it adds 1/2 a fallabella pony power I'd be surprised.
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Well not really mate, i've used k&ns on several cars and they have made a significant improvement. The main gain is mid-range, but there still is more power up top. The mk2 16v engine responded very well to this, as it is known not to be that responsive at low to mid revs.
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To be honest it's just the noise making you think it's faster mate.
Still cold air is what an engine likes - and by drilling loads of holes around your airbox all you're gonna create is loads of eddys and the intake plenum is gonna struggle calming all your air down.
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Whatever works for you mate! i do wonder where you get your info from.
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Do you do your own work on your car Slim?
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If I've ever heard a leading question that is one:
do you?
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As i said whatever works for you mate. Sports filters and induction kit don't work well on all cars. They do work well on gtis/vr6. It is a fact that drilling the box and putting in a filter will work as any engine works on breathing. The exhaust manifold on the 16v/vr6 is quite good as standard, the airbox is extremely restrictive. Typical gains are around 5%, not a lot but worth it for ?40.
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I was just curious to where you were leading with "Do I work on my car"?
3rd party air filters are less restrictive and increase airflow to a degree - poss the 5% you mentioned.
Induction kits are a bit of a mixed bag - like you correctly point out - they work for the older cars - but are useless on the majority of newer cars with fully computerised management systems (which merely recalulate the air/fuel ratio when extra air is admitted).
I can't really comment on a VR6 as I have never had/worked/modded on one.
They are a bit heavy so that is why I would retrofit a T rather than a V.
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Is the general consensus that an K&N air filter is good value? I have a 1991 8v and I am having it serviced and thought I may as well add a K&N instead of the standard VW air filter.
Does anyone know the price of a K&N one (I can?t seem to find a price on the net) and also the rough price of a VW one?
I?m not worried about making my car sound better, I just want it to run better!
Thanks
R
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Just found this, still not sure if I should buy a K&N!
http://www.pumaracing.co.uk/gentune.htm (http://www.pumaracing.co.uk/gentune.htm)
AIR FILTERS
Pretty much the same story as with exhaust systems these days. On older cars with carburetors the air filter box was usually a round plastic thing with a tiny snorkel tube for the engine to breathe through. This silenced induction noise very nicely but also strangled the engine. The filter itself wasn't the problem, it was the box it sat in that caused the restriction. Throw the box away and fit a K&N and a good few bhp was easily found. On modern fuel injection engines the induction systems are much better designed because the manufacturers can't afford to waste any available power. In my experience the filters themselves, which are usually flat square items, cause no restriction at all as long as they are new and clean. Replacing them with a "high performance" filter does absolutely nothing for power output. There is sometimes a bit of power to be found by enlarging the inlet tube in the bottom of the filter box or drilling a couple of extra 1" holes in the box. It's usually only a couple of percent at most though and hardly enough to even be felt in terms of extra performance.
The performance systems which replace the entire standard filter box with a tube and cone type filter achieve much the same thing as drilling a couple of holes in the standard box but for lots more money. You are unlikely to see more than a couple of percent extra power from these and very often they upset the standard fueling so much that power and economy in fact drop. To get any gain it's often necessary to spend even more money on a rolling road session to get the fuel mixture tinkered around with to restore it to optimum and often this is only partially successful and you end up with poor starting, shunting and stalling in traffic and other irritating habits if it isn't done right. Copyright David Baker and Puma Race Engines
Once again beware of magazine tests where the standard filter element isn't a brand new one in a back to back test or the results will be meaningless.
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That is just another opinion, there seems to many on this subject. From my experience on my vr6, the induction works well, on fully electronic systems it will work better as the ecu will automatically adjust the mixture.
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Slim, i was just curious if you are a hands on or not :-*
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I have been known to get my hands oily.
;)
Do you?
"they upset the standard fueling so much that power and economy in fact drop"
What I suspected - :P
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Whatever works for you mate! i do wonder where you get your info from.
Common sense chief - I just noticed your impertinent remark.
Where do you GET your info from? Back of a Ripspeed catalogue?
::)
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ladies ladies! vw's are crap
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Just my 2p's worth on air filters, have read that some "oil impregnated" performance air filters can damage the "hot wire" type of air mass sensor as these are very sensetive to contamination. I know this don't apply to the MK2 ;).
Steve.
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Whatever works for you mate! i do wonder where you get your info from.
Common sense chief - I just noticed your impertinent remark.
Where do you GET your info from? Back of a Ripspeed catalogue?
::)
Just wondered mate, but i actually get my info off the back of a cornflakes packet, like you i suspect ;)
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Nah, cornflakes have facts on the back . . .
I bet you've got a great toolbox - nice and shiny.
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You into boxes then? :-*
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yeah lady boxes!
what part of my info were you querying btw?
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I didn't actually mean to rude Slim, i was just interested if you do your own work, as you stated that drilling and filters do nothing at all. I wanted to know what you based that on, or what cars you have tried it on.
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Seconds Out!!!
Round 4! >:(
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when did I state that those two particular 'modifications' did nothing at all?
Please read my posts carefully before you jump in with accusations.
:)
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I don't think you emphasized the word 'little' enough
It merely makes your car sound louder
like drilling your back box on your mk2 escort back in the day -
if it adds 1/2 a fallabella pony power I'd be surprised.
Misread your posts ?? i think you need to re-read your posts ;)
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it adds a little to the power if you drill an airbox
like I said - and your point is?
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My point is, can you read? You said that a sports filter and a drilled box added a few pony power, then you said that you didn't. What are you on? LSD :-*
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I'd like an LSD in my next 'box.
oh, sorry, not that LSD ;D
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LSD isn't good, unless you like sleep walking ;)
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My point is, can you read? You said that a sports filter and a drilled box added a few pony power, then you said that you didn't. What are you on? LSD :-*
I never said it added nothing - YOU'D better learn to read and learn to insult better!!!
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LSD isn't good, unless you like sleep walking ;)
the last time I took it - it was bloody amazing
man
:)
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maybe you can increase performance by putting bigger brakes on it? hehehehe
Tin
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Interesting advice guys. I've decided to feed a rubber tube through from the cabin to the engine so I can blow more air in from my mouth when I have a need for speed.
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Hey that would be cool, cause the power that the airbox draws in the air would suck all the air out yer body, instant death, I dunno all these people who use the exhaust co posioning could just do it so much quicker and easier like this :)
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maybe you can increase performance by putting bigger brakes on it? hehehehe
Tin
Yeah, get another 20bhp out of that :-*
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LSD isn't good, unless you like sleep walking ;)
the last time I took it - it was bloody amazing
man
:)
Yeah not bad, i'm a bit too old for that sh!t now ;)
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My point is, can you read? You said that a sports filter and a drilled box added a few pony power, then you said that you didn't. What are you on? LSD :-*
I never said it added nothing - YOU'D better learn to read and learn to insult better!!!
I have to disagree there, i'm not bad at insulting people :-*
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leave slim alone you!!
you obv got all your info on cars from reading the back of product in halfords........
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No i get my info from actually working on cars myself, what about you?
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don't pick on the girls mate!
:P
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Why not? its fun. Hey golfgal are you that bird with the big arse? :o
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nah that's yer mum
:?P
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Just because you fancy her :-*
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jesus this is offtopic.
lol
quite fun to read tho
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Yeah I am. My arse is huge - if I sit in your car I'll knock off 20bhp.
I really don't think doin all that stuff does make a diff to your bhp but if you think it does then go ahed. I have a pipercross on coz I like the noise but thats me.....
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I drilled heaps of holes in the airbox, and removed the black tank thing in between the right wing of my 85MK2 gti8v and now it sounds like the car has a big exhaust system when i floor it, sounds quite nice when i floor it to the end of 2nd or 3rd gear
However i am sick of my golf as it has way too may annoying problems such as:
- sunroof leaks
- heater doesn't go
- mfa only displays time
- rear wiper jet doesn't work
- stupid f**king clicking noise everytime i go over a bump!
- changing from 1st to 2nd, and from 3rd to 2nd (mainly) gear is impossible without graunching when the car is cold
- coolant sensor complains there is not enuff coolant in the tank, and when i top it up, it pisses out coolant all over the engine when the engine temperature increases due to a crack in the coolant tank, and then the next day the sensor starts flashing again (REALLY :-X ANNOYING!)
I wish i still had my mitsubishi eterna zr-4, unfortunatly it got written off. Roll on end of December when i finish paying off my next zr-4 and sell my piece of sh!t golf.
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I'll buy it off you. Sounds like a minter
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Top
this is for VR6 so he can learn to read again
think before you rip before you make a chump of yourself
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Top
this is for VR6 so he can learn to read again
think before you rip before you make a chump of yourself
Sorry slim your the chump.
Back to basics.
The metering unit on a car does it exactly what it says on the tin. It meters the fuel. Right heres the good bit.
Your saying that by adding high lift longer duration cams and a sports flow air filter you will only gain say 2% extra.
BOLLOX
Learn the basics of engine tuning.
The given rule to increase engine performance is to firstly increase the swept volume of the engine by way of a capacity increase. If this is not possible then the next step as you know slim is to improve the breathing capabilites of said engine.
The best way to do this is to increase the duration and lift of the camshaft, do this and you will increase the amount of air flow you are able to suck in during the induction cycle.
Obviously you wouldnt go to all this trouble and then utilise the standard paper filter. You would use a sports air filter which will mean that there is less restriction on the air flow. I am not saying you will get massive power hikes as you wont on an atmospheric engine. You would have to employ forced induction for that.
You will in general terms and benchmark cases gain roughly 10 percent extra with a sports air filter, Its not hype its basic laws of physics.
What I am saying is that you have been negative on all points you have made and have not backed it up with any hard evidence so I think it is you that is the chump.
And if you wanna call me a chump I'll more than welcome it, I know the fundamentals of engines and how they work backwards, which is more than I can say for you.
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I have to say, that with the luxury of two near identical 8v's for comparison, I can relay this to you -
Car A has a K&N replacement panel filter and the standard exhaust manifold.
Car B has a K&N induction kit and a sports exhaust manifold.
Car B is remarkably quicker, it suprises me every time i drive it, much smother throughout the rev range (less flat spots).
Conclusion - Car A will get an induction kit when finances permit. But if you guys have the cash, i recomend getting the exhaust manifold upgraded too..
Happy Flooring..............!!!!!!!!!!
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Your saying that by adding high lift longer duration cams and a sports flow air filter you will only gain say 2% extra.
I never said that
Please read again
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You said adding a longer duration cam will do nothing unless you port the head. Well thats not really correct is it?
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OK - on re reading what I wrote - I could have put
"it would be of benefit to g/f head before adding cams"
you would recomend just plumping str8 for the cams without modding the head would you?
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Depends how deep your pockets are ! ::)
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I would say a sports air filter is a good investment purely because it will cost you less in the long run rather than having to keep putting in sh!tty paper ones.
Also it is a good base for engine mods that most owners start to indulge in as ownership and no claims bonus progress.
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No need in all arguing about the air filters just drill it if you want and dont if you dont want to simple.
Anyways I have had 3 mark 2's and did not bother drilling the air box because if you look on the side of the 16v filter box there is a flap thing that can simply be removed and thus gives the improved airflow. At least that way if you dont like it then just stick it back on simple ;).
I have found that the cars felt better personally but that is just my opinion. How do you like them apples............... ;D