Yeah, maybe a confusion of what is going on/being suggested.
I've never said push RP to the max. I've never 'got' 1800bar sensors except as a cheap replacement to the 1500bar one, OR where you might just want to get to around 1500bar with BIG injections on a BMW pump on the standard sensor and have some headroom with things. I've certainly never mapped a request for 1800bar, or even 1550bar+... the maths doesn't stack up for the injections and power requirements.
That isn't to say they are really great mods to make, but as you guys rightly point out, just because it 'can' reach 1800bar doesn't mean it should use it all to be considered good or worth doing! The BMW pump at 1500bar can make IQ's the standard pump can only dream about at 1500bar! (at the same rpm hehe)
It's all pretty much just a balance scale depending what you want and your budget I think.
High rpm = good because CFM is naturally higher = power. CR pumps run faster = can do more pumping to make that power.
High rpm = bad because crank inertial loads go up with square of speed = expensive to sort. Injections need to be done faster = need bigger nozzles or higher pressure, or both.
Low rpm = good because inertial loads are low, so even standard internals might run 500bhp at low enough rpm. Low rpm is good as piston speed is low, so injections can be slower.
Low rpm = bad because massive torque = bad for gearboxes/clutches designed for less. Need longer final drive ratio = hard to do? Pump probably still needs to be upgraded to flow a load of fuel at moderate to high pressures to get the IQ's needed for big power.
Loads more besides.
If you just look at things as a bunch of downsides and efficiencies then you start to hit many brick walls at different points, where adding X gets you an increasingly small benefit and increasingly large problems such as heat etc.
This is kinda why it's good to plan a goal output, budget, and intermediate steps. The 'stage' system kinda does that already but it gets confused after stage 2 currently.
If you want under 180bhp, don't get injectors or a pump. If you want 180bhp - 200bhp, get a pump and maybe injectors, or possibly vice versa depending on planned torque curve shape. Want over 200bhp, get both!
Not ideal but then we are building high powered engines to a low budget in most cases!
Dave
I've never said push RP to the max. I've never 'got' 1800bar sensors except as a cheap replacement to the 1500bar one, OR where you might just want to get to around 1500bar with BIG injections on a BMW pump on the standard sensor and have some headroom with things. I've certainly never mapped a request for 1800bar, or even 1550bar+... the maths doesn't stack up for the injections and power requirements.
That isn't to say they are really great mods to make, but as you guys rightly point out, just because it 'can' reach 1800bar doesn't mean it should use it all to be considered good or worth doing! The BMW pump at 1500bar can make IQ's the standard pump can only dream about at 1500bar! (at the same rpm hehe)
It's all pretty much just a balance scale depending what you want and your budget I think.
High rpm = good because CFM is naturally higher = power. CR pumps run faster = can do more pumping to make that power.
High rpm = bad because crank inertial loads go up with square of speed = expensive to sort. Injections need to be done faster = need bigger nozzles or higher pressure, or both.
Low rpm = good because inertial loads are low, so even standard internals might run 500bhp at low enough rpm. Low rpm is good as piston speed is low, so injections can be slower.
Low rpm = bad because massive torque = bad for gearboxes/clutches designed for less. Need longer final drive ratio = hard to do? Pump probably still needs to be upgraded to flow a load of fuel at moderate to high pressures to get the IQ's needed for big power.
Loads more besides.
If you just look at things as a bunch of downsides and efficiencies then you start to hit many brick walls at different points, where adding X gets you an increasingly small benefit and increasingly large problems such as heat etc.
This is kinda why it's good to plan a goal output, budget, and intermediate steps. The 'stage' system kinda does that already but it gets confused after stage 2 currently.
If you want under 180bhp, don't get injectors or a pump. If you want 180bhp - 200bhp, get a pump and maybe injectors, or possibly vice versa depending on planned torque curve shape. Want over 200bhp, get both!
Not ideal but then we are building high powered engines to a low budget in most cases!
Dave