1 pint per Horsepower per Hour is a long-standing rule of thumb for consumption - I've seen it engraved on early military aero engines from the 1914-18 era.

Most pumps are capable of keeping up for normal driving, it's only on extended flat-chat runs that you may get fuel starvation.

Vizard reckons 1 US gallon per hour for every 8 HP that the engine is capable of.

Going by that, you're looking for a pump capable of, say, 2.2 pints/minute for 130HP or 2.5p/m if you think you can screw 150 out of it.....  He doesn't say but I'm guessing he's talking crank HP not at the wheels....

Cheers, Ian

actually thinking now a modded Mini wouldn't get even 15mpg at 90 and can't find my notes on fuel use.  Car had an 8 gal fuel cell and I know I didnt use it all at Daytona in a sprint race which is mostly flat out.   But I was drafting the Neons.   Dim recollection used 5 gal in a 20 min race with 1 warmup and 1 cooldown lap, plus idling on the grid and getting to and from the paddock, maybe 40 minutes total but 30 at what you might call higher revs.  So my engine needed something like 4 gallons in 20 minutes?  That seems like a lot to me, 1 gallon in 5 minutes.   4 in 24 is 1 gal in 6 min...maybe.  But yeah, Holley pump, I think it was a red one can definitely do that.  Somebody on here with a big engine Mini will tell us what mileage they get on the freeway...
edit, I see MED Engineering is making new versions of the Arden.  Check with them.

Awesome info. thanks! 

Fuel consumption is not increased much over a single Weber on a 5-port unless you jetted wrong.  OK, you are on the autobahn fighting a headwind and trying to maintain 90mph, you will get what, 12 to 15mpg?   15 miles is a sixth of 90 miles, so in ten minutes you used a gallon. If you think 12mpg is right, 90mph is 1 1/2 miles per minute, it takes 8 minutes to go 12 miles.  Put ten feet of hose on your pump, push the fuel through a Holley pressure regulator set to 2 psi, see how long it takes to push a gallon into a bucket.  If it takes 10 minutes, I would say you should be OK but look for a bigger pump anyway.  If its less than 8 minutes, I think you are OK.  What you want is decent flow at low pressure, maybe consider upsizing the fuel line between pump and carbs and make sure the regulator is not far from the carbs.

Hoping someone might have a little input. Just got a car into our shop with a Arden 8-port 1380 and dual 45 weber carbs. Was actually the cover car for mini world magazine in november 2001. Has spent the last 16 years in a garage in Los Angeles and we're now getting it road worthy again. A couple of the fuel lines have deteriorated pretty badly and a cheapo aftermarket fuel pump was installed back in 2014. Currently replacing the lines and have installed a Lucas electronic pump for the time being, though i have doubts that it'll keep up with the fuel demand of the big Webers. Anybody know how much fuel is needed for a setup like this? Been looking into a Facet pump for better looks and better flow, but is that overkill? Thanks in advance.