So what is the optimum location for a high pressure fuel pump? I have an MK Indy

Cheers

Most people go engine bay to avoid long runs of HP.

High pressure pumps are better at pushing than pulling. So usually best fitted close to the tank and low down to give a good gravity feed into them. Mounting at the front sucking feul all the way from the back will cause a lot of cavitation and bubbles in the fuel.

An age old question that has been asked many, many times before, see post just earlier today, and I believe there's no defining answer. A pump does push better than it pulls, but that said, I fitted mine in the engine bay and have never had any problems.Just ensure you run the fuel lines inside the car to prevent any external damage and that all joints are secure to prevent, depending on which position you decide on, leaks from high pressure or air being suck in. Sorry Chaz, x1 for engine bay & x1 for fuel tank and x1 undecided, you are non the wiser are you.

[Edited on 22/2/16 by LBMEFM]

There is good reason why OE cars have the fuel pumps either in-tank or sitting just below the tank.
The pumps are not designed to be suckers at all. So yes, you may get away with one under the bonnet, but what is the disadvantage of having it under the tank. Surely length of HP fuel piping is not a reason? Not difficult to get that correct. Besides, some pumps require 1/2" feed, try running that the length of a car!

Thanks guys, even if there is no definitive answer I thank you for all the other reasons surrounding to help me decide. Lots of stuff I still don't know about cars!

or low pressure pump at tank to swirl pot and HP pump under bonnet...

seven type cars are so short it generally doesn't matter.
however, I would put the high pressure pump at the back, and a pressure regulator as close to the injectors as possible.
ideally the pump would be in the tank as this aids cooling, and its quieter