Direct injection, the lazy way out?

[theq]

I'm a bit lazy and don't feel like fabbing up evaporator tubes with multiple injectors. I'd rather build a direct injection setup with a high pressure pump and one big  injector. Will 200PSI be enough? The turbo wont make more than a PR of 4.25 (that's what a GT45 is rated on the comp map anyways, I doubt I'll reach that pressure unless I try methanol-water injection upstream of the compressor, I hear some diesel guys use windshield wiper fluid)

I've found that procon vane pumps can reach upwards of 200psi some listed on ebay are as high as 250. 


www.edcodistributing.com/pdf/2011matrix.pdf this webpage has all the info related to procon's model numbers and what kind of pump it is based on that number. This will tell me what kind of pump I can use. Nitril seals to handle the diesel better (diesel really chews at rubber over time) etc.

TLDR: I want to build a directly injected unit, will 250PSI work out with PRs of 4.5?

[racket]

Yes , 200 psi should be enough.

Theres no need to go higher than a PR of ~3.5-4 :1 as the drop in comp stage efficiency above that point means theres no change in power output from the engine , all we do is use good turbine power flogging the air to death .

[turbo]

Nov 30, 2018 20:09:40 GMT -5 racket said:

Yes , 200 psi should be enough.

Theres no need to go higher than a PR of ~3.5-4 :1 as the drop in comp stage efficiency above that point means theres no change in power output from the engine , all we do is use good turbine power flogging the air to death .

[theq]

Nov 30, 2018 20:09:40 GMT -5 racket said:

Yes , 200 psi should be enough.

Theres no need to go higher than a PR of ~3.5-4 :1 as the drop in comp stage efficiency above that point means theres no change in power output from the engine , all we do is use good turbine power flogging the air to death .

Would it do any good to purchase a flame tube of an old engine from Ebay? As long as it was similar to what jet specs say?

[racket]

Yes and No ...............it might be more work to modify it to suit than making a bespoke one .

[theq]

Dec 1, 2018 18:22:40 GMT -5 racket said:

Yes and No ...............it might be more work to modify it to suit than making a bespoke one .

Thanks a bunch!

[smithy1]

It can be done and once setup is virtually trouble free.
I'm running a combustion chamber which is a modified Rolls-Royce C20B unit, modified of course due to vastly different pressure ratios between the C20 and the GT6041....
I made it to suit the GT6041 turbo....also running a single modified "dual stage" C20B injector....but it runs well over 500psi to try and get good atomisation, she's a bit fluffy at idle when cold but once the "innards" are warmed up, she's good and smooth.
I have a high pressure fuel pump, also from a C20B which is easily capable of over 3000psi....works very well indeed.

Cheers,
Smithy.