[Guest]

im sure you get fed up with this,but i for one am eternally gratefull
as im sure is julian (super l ),who is in a similar position.
please understand,i cannot get this info ANYWHERE ELSE !

final question,in as near to laymans as you can (no a levels here !)
std injectors
assuming pipework is not a restricting factor,i.e the pure flow capabilities of the injector
at 3.0, 3.5, 4.0, 4.5, 5.0, bar

and the other way round,
80,85,90,95 % duty cycle equals what base pressure in bar


did you find a map for the makinen turbo 15 ?
thanks

 

[Guest]

MC,
In pure flow terms the standard injectors at the various pressures will flow as follows:

3 bar |EQU| 560 cc/min
3.5 bar |EQU| 605 cc/min
4 bar |EQU| 647 cc/min
4.5 bar |EQU| 670 cc/min
5 bar |EQU| 723 cc/min

and if the injectors are flowing at 80,85,90 and 95% then the base pressure could be:

80% |EQU| 448 cc/min |EQU| 27.8 psi
85% |EQU| 476 cc/min |EQU| 31.4 psi
90% |EQU| 504 cc/min |EQU| 35.2 psi
95% |EQU| 532 cc/min |EQU| 39.3 psi
100% |EQU| 560 cc/min |EQU| 43.5 psi (3 bar)

And which specific turbo map are you looking for as I've found quite a few on the web?

Hope this little lot helps you out

Andy

 

[Guest]

thanks,but my head hurts,
i think ive asked the wrong question......
ok
what is the point at which the std injectors reach 95% duty cycle,in bar (base pressure ) ?
i am not sure if this is the right way to put it ?????

or,
what is the highest recommended base pressure,set at 1000rpm,full system voltage,vac pipe disconnected ?
and what would the corresponding duty cycle of the std injectors at this figure.

do you know what im trying to get at ????

thanks.........and dont use any big words !

 

[Guest]

80% is the maximum duty cycle the injectors should be run at.

As for raising the pressure - the spray patterns will suffer at high pressure - 80-85psi max. including the increased pressure from the regulator due to the boost pressure.

So your limit is 80-boost pressure.......say boost maximum is 25psi - base pressure would be 55psi.

Your standard 560cc/min injectors would then be equivalent to 658cc/min injectors.

I would not recommend this massive sort of increase in pressure -
1. Your fuel system is more likely to develop a leak
2. More importantly - your fuel pump will struggle to flow enough at high pressures.
3. Injectors are designed for 3 bar operation.

I would not recommend more than 5-6psi increase to overcome minor shortcomings in the injector capacity.
A big increase in base pressure is a bodge - it's time to move to bigger injectors!


Haven't found that Makinen GSR map yet.