power increases in modifed 8v gti

hi i have been toying with engine swaps but just seems alot of messing that i aint got the skills to do them hate eletrics  .so i am thinking of just making my engine better but whats the best combos to get the best results not after better top end just from take off middle range thanks

Without removing/replacing engine anyway, you're looking at a max of around 125bhp, I'd say.

Big valve head, ported and polished
Matched port/polish on inlet manifold
Audi 5 cyl throttle body, knife-edged
4 branch exhaust manifold (match ported and polished) and sports exhaust system
Audi 5 cyl warm up regulator
Higher lift and longer duration cam
Fuelling properly set up, eg on a rolling road or equivalent

all that work for not a massive increase not really worth the cost is it?
any idea of the cost of getting some one to wire a engine in for me say g60 or 1.8 t thanks

the DX can be got to 140 - 150 or so with out too much hassle, it just depends ho deep your pockets are as you will need a modded head for that kind of power, with the mods paul has listed (I think hes been a bit conservative with his power estimate)

a 1.8T is the best engine bang for buck in my view but a drive in drive out isnt cheap, and if your handy ith the tools it can be done your self. theres enough info on the site to do it, but agai it will cost. as they say nothing comes for free.

hibbs said

all that work for not a massive increase not really worth the cost is it?
any idea of the cost of getting some one to wire a engine in for me say g60 or 1.8 t thanks

i know a few people with this setup and they can easily outpace 16v motors.
i think its more like 130-140bhp with those bits!

Well, I'm happy to be proven wrong, all I have to go on is previous dyno plots, 1/4 mile times, etc. There is a lot of internet horsepower out there, though.

paul_c said

Well, I'm happy to be proven wrong, all I have to go on is previous dyno plots, 1/4 mile times, etc. There is a lot of internet horsepower out there, though.

dont go by horsepower it means nothing in real world driving!
the torque and powerband are better once cam'd and breathing better and then fueling better which then makes the car rev better and hold the gears through the rev range longer. how can all this be shown on a rolling road by a graph!
my car is 112bhp spot on the dyno has proven it several times.
but take mine out against another 112bhp car and it reacts like a car that has much more power and torque. most people that have been in the car are kinda shocked that the car is only 112bhp.
but what people dont see is that the engine is in peak performance (serviced)
and that the car weighs only 850kg which makes it something like 135bhp per ton.

Bling said

paul_c said

Well, I'm happy to be proven wrong, all I have to go on is previous dyno plots, 1/4 mile times, etc. There is a lot of internet horsepower out there, though.

dont go by horsepower it means nothing in real world driving!
the torque and powerband are better once cam'd and breathing better and then fueling better which then makes the car rev better and hold the gears through the rev range longer. how can all this be shown on a rolling road by a graph!
my car is 112bhp spot on the dyno has proven it several times.
but take mine out against another 112bhp car and it reacts like a car that has much more power and torque. most people that have been in the car are kinda shocked that the car is only 112bhp.
but what people dont see is that the engine is in peak performance (serviced)
and that the car weighs only 850kg which makes it something like 135bhp per ton.

Well, in addition to the max power, the dyno shows a plot of the torque over a range of rpm. So its pretty easy to interpret that to work out how the car will behave on the road.

Torque is where the 8v wins over the 16v and where tdis win hands down which is why my Audi is faster for everday driving    I have a RR prinnt out somewere from a while back showing mine at 118bhp with out the 16v WUR and with the fueling a bit iffy… Ill put money on me now being around 125bhp mark and if the torque curve is like it was before when the fueling was iffy ill be very very happy!! as it was nice and smooth and came in pretty early too.

well had ahunt round on net . on cgti theres a deal with the man in the shed for polished and ported heads for a about 300 is this agood price theres loads of people on there saying how good his work is.

hibbs said

well had ahunt round on net . on cgti theres a deal with the man in the shed for polished and ported heads for a about 300 is this agood price theres loads of people on there saying how good his work is.

Its the deal I'd go for but bear in mind its pointless unless you also get your inlet manifold and exhaust manifold (4 branch?) matched to the head.

i understand that but was reading that 4 brand manifolds are just awaste of money and not worth borthering with and cost about 200 plus then got to get it polished and ported to match is that right or am i just confused again

hibbs said

i understand that but was reading that 4 brand manifolds are just awaste of money and not worth borthering with and cost about 200 plus then got to get it polished and ported to match is that right or am i just confused again

Not worth bothering with up to around 120bhp, since the stock one flows well. Unsure at what point the stock manifold becomes a restriction and you want a better flowing one. It also means you can wrap it, which is supposed to gain you more power. If it doesn't, then it helps with temperature control under the bonnet, for sustained running (eg a trackday).

And what about CNC ported head for the 8v??With polished 4 branch manifold and a sport camshaft,the power gains have to be obvious,perhaps more in Torque than PS.

javiCabrio said

And what about CNC ported head for the 8v??With polished 4 branch manifold and a sport camshaft,the power gains have to be obvious,perhaps more in Torque than PS.

CNC itself, doesn't automatically add the power - its where you remove the material to port the head, which is critical, not how its done.

torque = power x speed (rpm)

So if the gains are more in torque than power, are you saying the power (torque) is delivered lower in the rev range?