1 month old 1.8 sri

**willie76** · 2nd October 2007, 16:48

Hi to everybody i need some info my old x plate sri 140 seems to be alot quicker than my new one any one know why..........????? also where can i get a new alloy as i let my wife drive it and she kerbed it any info would be great

thanks ....willie

**VauxVeteran** · 2nd October 2007, 16:50

BHP mate, the 140 has them the 1.8 doesn't, tis a slug pulling a tanker tbh.

**Big Sig** · 2nd October 2007, 18:07

errm, the new 1.8vvt is 140bhp. I guess the c is a heavier car. Look on the for sale section or on e-bay for a new wheel. Could it be repaired?

Also don't forget its new so it will take a good 10000 miles to loosen up fully, I know my astra did - z18xe motor in that.

**VauxVeteran** · 2nd October 2007, 18:12

I guess I'll stand corrected there as it does indeed rate at 140, learn summin everyday.

Can't understand how they get these figures, a 2.2 is 155 and hits 60 in 8.6, a 1.9 CDTi 150 is 150 obviously and hits 60 around the same time, a 1.8 is 140 and is about as fast as a 2.0 DTi which only had 110 iirc.

**Jamie** · 2nd October 2007, 18:33

Originally Posted by VauxVeteran

I guess I'll stand corrected there as it does indeed rate at 140, learn summin everyday.

Can't understand how they get these figures, a 2.2 is 155 and hits 60 in 8.6, a 1.9 CDTi 150 is 150 obviously and hits 60 around the same time, a 1.8 is 140 and is about as fast as a 2.0 DTi which only had 110 iirc.

That'll be down to the difference in torque between a diesel and a petrol mate.

**Big Sig** · 2nd October 2007, 19:36

^^yep as above. The VVT's really need a good thrashing to get moving. Just like the toyota VVt's

**Ste** · 2nd October 2007, 19:56

Power = torque x rotational speed

As diesels tend to die at around 4500 rpm, the torque is much higher for the same power than, say, 6500 rpm like a petrol

Grandmother and eggs spring to mind now.....

**chazd** · 2nd October 2007, 20:08

the vvt is the diff as said. likes to be revved a bit more!

**Freefaller** · 3rd October 2007, 09:42

Simple way to get an impression, Power divided by mass.

Eg for a Vec C (150ps diesel) Power = 148bhp , mass = 1522 kg

So power to weight = 148/1.522 = 97.24 bhp per tonne.

But my Vec B 2 litre petrol was 1374 kg, so with only 134 bhp

Power to weight = 97.53 bhp per tonne

Just for comparison.

1.8i VVT Vectra C = 102 bhp per tonne
2.8i V6 Vectra C = 156 bhp per tonne

And a F1 car has about 900 bhp to pull 550 kg around = 1630 bhp per tonne. But that 900 bhp is developed at about 18000 RPM.........

So the two Vectras above have very similar power to weight ratios, the differences in acceleration figures and perception from the driving seat are purely down to the differing torque curves of the engines and the gearing.

Calculate it out for yourself, for different cars and different engines you've driven. (My personal view is that dropping much below 100 bhp per tonne will feel noticeably sluggish)

A smaller petrol engine like the 1.8 VVTi will have to rev hard to produce it's power and torque so, unless you're caning it, will feel slower than a diesel or big petrol lump producing loads of torque right through the rev range. The 1.8 VVTi produces max power at 6300 RPM, the 150 diesel at 4000 RPM.

Hope that helps and doesn't confuse everyone too much!