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Model specific boards => Golf mk2 => Topic started by: GolfDan on 09 February 2005, 21:28

Title: What power increase
Post by: GolfDan on 09 February 2005, 21:28
will a race cam and 4 in 1 manifold give me (approx) on my 91 8v its fairly quick at the mo but the local civic boys need blowing out of the water completely

Dan
Title: Re: What power increase
Post by: Dizzie on 09 February 2005, 22:40
10bhp if you're lucky. Fit nitous :wink:
Title: Re: What power increase
Post by: piggy on 10 February 2005, 01:03
You know your stuff Dizzie.

Is that a shorter faster version of Nitrous? :laugh:

 :wink:
Title: Re: What power increase
Post by: Gambit on 10 February 2005, 13:26
a race cam will make the car undriveable in normal day to day driving
Title: Re: What power increase
Post by: gibby on 10 February 2005, 13:38
a race cam will make the car undriveable in normal day to day driving

Out of interest, why ? What's the difference ? 
Title: Re: What power increase
Post by: davidhawkins_78 on 10 February 2005, 13:50
A race cam has the cam profile engineered for power @ high revs ... imagine a car with no power till 5000 rpm then it wanting to rev like nutter till 9000 rpm upwards!
Title: Re: What power increase
Post by: gibby on 10 February 2005, 14:02
I see. Thanks for the info Mr H.  :smiley:
Title: Re: What power increase
Post by: GolfDan on 10 February 2005, 14:43
i see a rethink is in order then!!  :embarassed: what would you recommend to go with the 4 2 1? thanks for the advice so far chaps
Title: Re: What power increase
Post by: ...joe on 10 February 2005, 22:57
get a decent air filter in your standard air box, with all the crap taken out of it if you haven't done that already. open the air box and you should see a trumpet (i'm assuming its a digifant by the age) thingy throw it away and then take a big drill and drill some big holes wing side (ONLY) of the box. thats a start. then get a decent exhaust to go with your manifold, then ported head, then cam then have it blueprinted..... it goes on and on...... !!!
Title: Re: What power increase
Post by: tinman on 11 February 2005, 00:59
A race cam has the cam profile engineered for power @ high revs ... imagine a car with no power till 5000 rpm then it wanting to rev like nutter till 9000 rpm upwards!


errrm, not quite.

the "normal" driving becomes a pain cause the engine is rough as nails until you reach a high rev. you can expect idling to be >2000rpm, which makes the car especially painful in town.

you can run any motor up to 9000rpm, you just need to change the return springs on the valves. the reason that engines have a rev limiter is because the the valve generally wont shut fast enough, causing an overlap, and then hell kinda breaks loose. by putting a stronger return spring in place, the valve snaps shut that much faster. thereby allowing you a higher rpm without blowing the engine away.

forget drilling airboxes and the like and changing the exhaust.

generally, get yourself a new standard exhaust, get the air filter changed, and renew the injectors. far simpler and much better results than faffing around in the engine bay for weeks.

if that doesn't work. buy a 16v.
Title: Re: What power increase
Post by: Dizzie on 11 February 2005, 21:21
the 4-2-1 manifold has a better rev range than a 4-1 version. usually the 4-1's are only used on race cars where the revs are constantly high.

A cam can make a slight difference to a road going car, but like gambit said. one that will give a decent increase in power will make it a sod to drive round town and really f**ked up idling.
Title: Re: What power increase
Post by: ...joe on 12 February 2005, 09:50
yeah my cam can be a bit annoying but you do really notice the difference when it does kick in!!! but i did the exhaust/filter first and have just sent my head away to be worked.
then, as i'm a bit worried about stainless manifolds cracking, i'm using a ported g60 exhaust manifold mated to a miltek downpipe. i know a guy who specialises in tuning g60's (john mitchel racing, look at all the good things said about him on the corrado forum!!) and they get amazing results from using this combination so i thought i'd give it a go!!! i'll let you know when its finally all back together.
Title: Re: What power increase
Post by: VeeDubGTI16v on 12 February 2005, 10:05
A race cam has the cam profile engineered for power @ high revs ... imagine a car with no power till 5000 rpm then it wanting to rev like nutter till 9000 rpm upwards!


errrm, not quite.

the "normal" driving becomes a pain cause the engine is rough as nails until you reach a high rev. you can expect idling to be >2000rpm, which makes the car especially painful in town.

you can run any motor up to 9000rpm, you just need to change the return springs on the valves. the reason that engines have a rev limiter is because the the valve generally wont shut fast enough, causing an overlap, and then hell kinda breaks loose. by putting a stronger return spring in place, the valve snaps shut that much faster. thereby allowing you a higher rpm without blowing the engine away.

forget drilling airboxes and the like and changing the exhaust.

generally, get yourself a new standard exhaust, get the air filter changed, and renew the injectors. far simpler and much better results than faffing around in the engine bay for weeks.

if that doesn't work. buy a 16v.

err i think you will find you can get a wide range of cam profiles, so every ones gonna be different :wink: you can get road cams, you can get race cams, as soft or as hard a profile as you like :wink:

and theres no 9000rpm limit on an engine, again they can rev more or less. after the stiffer valve springs you can put some solid lifters in which will let it rev more. its not as plain cut as you say :grin:

its basically a case of your engine is as quick as your wallet is big :cry:
Title: Re: What power increase
Post by: mk2gtimatt on 17 February 2005, 10:40
y not just fit a vr6 engine!?  :rolleyes: if u want to spend that much on ur engine just stick a bigger lump in there... job done mate!
Title: Re: What power increase
Post by: kegs on 17 February 2005, 13:13
SORRY TO HI-JACK THE ORIGIONAL QUESTION,

i also have a H reg 1.8 8 valve, fitted with a full magnex system. I have polished the head myself, and even now convinced myself the car runs quicker just by taking some time polishing the head.

my next plan of attack was an induction kit, either jetex, k&n, pipercross...

has anybody got good or bad experiences with any of these???

also, i was thinking of fitting a power rohr, are these any good??

and can the power rohr be fitted with an induction kit????

cheers

kegs  :laugh:
Title: Re: What power increase
Post by: ...joe on 17 February 2005, 21:03
power rohr is just a metal pipe. does nothing except looks shiny! which is the only reason i got one and because it was fecking cheap off ebay! they will work with induction kits as they fit on to your manifold and nowhere near your induction kit. basicly they are show not go!!!!

induction kits aint worth it, get a decent panel filter from K&N, jetex, green etc.... i'd go for cotton gauze over foam any day but that may just be personal preferance. then, yours must be a digifant, make sure you've taken the crap out of your air box and drill some big holes in the wing side of the bottom of the airbox. by crap i mean if you ope  the box there will probably be a trumpet type thing in there. pull it out and anyother junk and throw it away.

job done.
Title: Re: What power increase
Post by: kegs on 18 February 2005, 08:02
cheers for that,

i imagine pulling the guts out of the airbox will improve air flow through the sytstem, as will adding a few holes. Will adding the holes also improve the induction note on the car? That was to be my second reason after power for fitting an induction kit!!

i will see what panel filters i can purchase at dubfreeze this sunday

thanks again,

kegs
Title: Re: What power increase
Post by: ...joe on 18 February 2005, 10:52
yeah drilling holes will add to the sound. in fact i ran a k&n induction kit for about a week, before going back to my air box and i think my box is louder. it seems to 'bark' more don't know if its an echo thing going on or what but its much better.
Title: Re: What power increase
Post by: kegs on 18 February 2005, 12:27
i am going to pull the guts out of the airbox this weekend, i am going to drill holes wing side, and remove the bit of plastic in the inner wing, should i put some mesh in the inner wing aperture to stop crap coming through? i cant wait to hear it :evil:
Title: Re: What power increase
Post by: ...joe on 21 February 2005, 21:08
nah shouldn't worry about mesh too much. wont hurt to do it though.............
Title: Re: What power increase
Post by: kegs on 28 February 2005, 12:50
I remove my airbox this weekend, and removed the plastic panel in the inner wing. I also disconnected the flexible pipe to manifold and blocked up the exit. i then cut out the trumpet in the air box lower. and drilled some holes wing side.

My question is, do you remove any stuff from the upper half of the airbox??

cheers
Title: Re: What power increase
Post by: ...joe on 01 March 2005, 17:30
no leave the top part alone, you've done the best you can....................