I've lost 10bhp...

Si_GTi · Post by **Si_GTi** » Mon Jan 29, 2007 5:38 pm

In answer to Andy's question, I can spin the wheels up quite nicely in 1st in the dry with a few revs, and although normally I wouldn't condone such behaviour I felt that in the name of research I should at least give it a go

The power is definitely there, car really starts to pick up as it approaches 3500rpm and beyond that I'm not sure as there are no sensible places on my 2-mile commute to work

that I can let her off the leash!

Fuel consumption hasn't increased, I'm getting ~270 miles before filling up when the light comes on.

Beats me as to what's wrong with her, will persevere with locating a vag-com

Thanks all!

Tigz · Post by **Tigz** » Mon Jan 29, 2007 5:48 pm

Your exhaust shouldnt cause you to lose power.
Even a poor powerflow exhaust you would expect a gain of 1BHP.
Its the reduction in tourque from the lack of back pressure.

When was the cam belt replaced?
What fuel did you have in?
How much pressure is in your tyres?

Si_GTi · Post by **Si_GTi** » Mon Jan 29, 2007 5:58 pm

Tigz wrote:When was the cam belt replaced?
What fuel did you have in?
How much pressure is in your tyres?

Cam belt was done at around 52k miles, I'm now at around 78700 miles. I would have to dig out the original receipt to find out exactly when the belts and water pump assembly were changed.

Car is running on BP Ultimate 97RON and has been for some time now, certainly for the last few months without any interruption.

Tyre pressures I don't know, I haven't checked them for several weeks

Thanks

jezmk4 · Post by **jezmk4** » Mon Jan 29, 2007 6:15 pm

Redline wrote:Peak power should be at 6500rpm

Well

it will actually Vary a fair bit with different modifications

Tigz · Post by **Tigz** » Mon Jan 29, 2007 9:01 pm

Check the tyre pressures tommorrow before you start to worry.
If they are lower than recomended theres some of your power loss.
All of it Id be supprised of, but certainly a few BHP.
I know of a Ford on a Rolling road that made 8BHP on his second run on the rollers by adding 10PSI!!

mk4 glx 1.6 · Post by **mk4 glx 1.6** » Tue Jan 30, 2007 10:25 am

Si_GTi wrote:on my 2-mile commute to work

If I only had a 2 mile commute, there is no way i'd use my car (unless it was raining) !

Mouse_GTI · Post by **Mouse_GTI** » Tue Jan 30, 2007 11:40 am

You tried timing rough 0-60's Si?

garnier · Post by **garnier** » Wed Feb 07, 2007 4:36 pm

VVT on a Gti? Isnt this variable valve timing as in japanese toyotas, as in vtec? I've never heard of this on a polo gti - and it's certainly not noticable on my gti (saying that, i did used to drive a vtec honda)

I wouldnt be too fussed about the loss of bhp - you could take it to a tune up guy and he should be able to sort it.

But look at that blue torque line, the way it shoots up at low revs! Thats what I love about the polo gti - it has the most amazing torque, something you dont really appreciate until you driven a flat torquer, like vtec

Redline · Post by **Redline** » Wed Feb 07, 2007 4:53 pm

garnier wrote:VVT on a Gti? Isnt this variable valve timing as in japanese toyotas, as in vtec? I've never heard of this on a polo gti - and it's certainly not noticable on my gti (saying that, i did used to drive a vtec honda)

Yes it has VVT on the inlet system. Changes at around 4500-5000rpm more noticeable if you have a BMC induction kit fitted.

Si_GTi · Post by **Si_GTi** » Wed Feb 07, 2007 5:36 pm

I'm getting the car plugged into a vagcom on Saturday, fingers crossed.

I also had a chat with a master techie at VW yesterday who suggested I check on the condition of my cambelt tensioner...

garnier · Post by **garnier** » Wed Mar 07, 2007 9:06 pm

Did you ever get this sorted? what was wrong

polo_gti21 · Post by **polo_gti21** » Wed Mar 07, 2007 9:34 pm

ive got a powerflow full system and my tuner said that it had lost power top end but you dont really notice it that much, as for loss of power i changed ht leads and pugs and use shell v-power fuel and its worked wounders still get polo fever tho. the feel of vvt when it kicks in is such an adrenalin rush

Si_GTi · Post by **Si_GTi** » Thu Mar 08, 2007 1:44 pm

I haven't done anything about this yet, no. Its not really too high on my priorities at the moment!

I'll add the HT leads to the list of possibles though...

---Carl--- · Post by **---Carl---** » Thu Mar 08, 2007 3:02 pm

hex_da_rex wrote:Being paranoid now... How can you definately tell that the vvt is working?

ye ... and how do u exactly feel it kick in ? im confused, i cant feel anything kick in really lol

Tigz · Post by **Tigz** » Thu Mar 08, 2007 3:27 pm

You can hear the change in engine noise.
You cant really 'feel' anything.
Its not a honda