Just curious, I read different things about this topic. My mods are below, and will be adding HKS 280's/Alky injection/TME turbo with the 10.5 hotside. 1/2 of the people say stay stock injectors, 1/2 say need larger injectors. What do you think and why? the turbo is really a "lateral" move, not really an upgrade to a larger turbo. Is there any gain in shoving more fuel in the combustion chamber, when I cant shove more air in there to mix with it? Which would be seen with the LARGER Turbo? Help me out, like you always do. Need advice from the "tuner" camps if possible, as I am NOT the only one with this question lingering in my head.
Thanks in advance,
Kevin

 

Kevin, IMO If you are going to add the TME turbo and optimize the flow of the rest fo the car i would at least go 680cc's to be safe. I have read numerous posts where the stock injectors are enough for the stock turbo, but i seen IDC of 92% with my stock turbo at 23 psi.

I have a Buschur stage 4 and am running 750cc because when i went to order the 650-680cc's were not in stock.

 

Thank you VTECH8TR, now can you find me some for a decent price? Doesnt matter the size! ( at least thats what my wife says!)

 

It's better to upgrade to larger injectors instead of running stock ones at high injector duty because if they stay open for too long they might go static and fail. High RPMs, high load require high fuel flow, simple as that. Can you imagine what happens when the injectors let you down (i.e. run lean) when you need it the most?

A lot of people would advise you against upgrading injectors due to poor idle quality, which is true only if the EMS is unable to cope with the reduced injector duty.

 

With fuel, always better safe than sorry.

 

I'd go at least 660, if not 720 (to add a bit of headroom for the future in case you swap turbos again) - either would work, and with a Greddy/Blitz injector, they are also the same price

As for the poor idle quality with either of the above, only at the hands of a tuner who has no idea what he is doing...a 660 or 720 can idle just as evenly and smoothly as stock, with even just a reflash (no need for standalone)

Let me know if you need em

 

I have to wait and see about this VISHNU SMART package, and how it will handle the injectors, I am, I guess, in a "Holding-pattern", thank-you for all your info, it is very informative.

 

680's are plenty. You won't need a reflash to get them to idle well. There's this wonderful thing called closed-loop.

 

thanks Wideband!

 

Nice thread smoked. I have been wondering the same thing and thanks for the information!

 

Your very welcome rook, I think there is a lot of grey matter on this site, and all the answers are here, we just have to ask the Questions!