How Fast.

[AlandAnn]

Just a quick question:
How fast should my t25 1.9 petrol be ?
At the moment, I can get up to 65-70 downhill.
If that's slow, how do I get better performance ?

[silverbullet]

DF or DG? Neither are quick. How much fibreglass, chipboard and appliances are onboard?

[R0B]

How fast on the flat.Hills come in all sorts of declines.Down porlock hill you could probably get it to 90 mph.(Not recommended)And remember they are not racing cars.

[ChrisTriple]

Just a quick question:
How fast should my t25 1.9 petrol be ?
At the moment, I can get up to 65-70 downhill.
If that's slow, how do I get better performance ?

50 65 on the flat

up hill 20 to 40 depending on how steep maybe even 10

Down hill I'd be happy with whatever it is

[BOXY]

Mines a 2 ltr air-cooled but anything over 70 is a result.

[Bigjcc55]

I like to sit at 60-65 and get some kind of economy, will go faster but don't see the point pushing it, above 70 it turns into an oil boiler.!

[Ruralman]

I tend to stick to 55-60 but Sergy has been known to creep over 70! When I'm not paying full attention
By the way Sergy is a 1982 2.0 Petrol Hightop T25 campervan
Regards
Keith

[AlandAnn]

Thanks All, guess my boy racer days are over.

[Dazco]

1.9 DG in decent fettle should easily do 70 on the flat , having said that i was struggling to do 45 last night on the M18 with a head wind

[CJH]

1.9 DG in decent fettle should easily do 70 on the flat

Agreed - my DG gets to 70 very easily on the flat, and if I stop watching the speedo I'll often find it's crept up to 75. And even at 75 there'll still be more pedal left - how much I don't know as I always back off at that point. Anything over 70 makes me a bit nervous unless it's a totally calm day.

When I first got the van, top speed was about 65, and after a couple of weeks touring Scotland it returned about 24mpg average. I later discovered that there was some slack in the throttle cable, meaning I wasn't getting full throttle even with the pedal to the floor. I adjusted that and top speed went up but I've never again managed to get the same fuel consumption. That last bit of throttle makes a big difference to consumption.

[BOXY]

Don't forget to factor in speedo error the 70.6 mph on my satnav was probably closer to 75 mph on the speedo.

[Ralf85]

60mph is a comfortable driving speed on motorways in these bricks. That keeps you from being tail gated by faster vehicles in the outside lane and provides a bit more acceleration for overtaking trucks.
On the subject of speedo readings, mine are totally accurate on 15" wheels. It reads the same as the satnav. Why do other people's speedos have errors?

[silverbullet]

Because any speedo is always set to read a good 5% fast. Bigger tyres mean more distance covered per revolution, so the speedo then reads proportionately lower i.e. closer to true road speed.

[ghost123uk]

Just to add to the stats = Tin-Top with average style camping furniture (Fridge / Cooker / Sink / Bed / Cupboards etc) DG power in good nick, slightly larger than standard tyres, cruises happily at 70 on the motorway, I have seen 85 on the flat, but I would not do that at all often. Because of my "taller" tyres, my speedo is pretty much spot on checked against my Sat Nav.

As said, so much varies on which engine (DF / DG for petrol WBX), the weight of the van, the condition of the engine etc etc.

[CJH]

Once I get past the 'wobble zone' on my speedo, it's pretty accurate against the satnav, and I'm on standard 14" wheels and tyres.

[pedant mode]The weight of the van only affects your ability to accelerate and go up hills. On the flat, top speed isn't affected by weight. F=ma, so for a given net force 'F', 'a' will be smaller for a bigger 'm'. Once the forces of air resistance and rolling resistance equal the force coming from the engine, then that's it - net force equals zero so no more 'a'. The major one there is air resistance, so a sleeker tin top ought to go faster than a high top or pop top. I guess rolling resistance and other friction sources might be increased with a heavier van, but I think that would be a very minor effect.[/pedant mode]