how much can my injectors handle?
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So Im continuing to piece together my turbo setup, and am trying to decide which turbo to go with. im looking at either a godspeed gt25 with an 8psi actuator, or a gt28 with a 14.5psi actuator. I already purchased some 460cc injectors, and my plan is to go with MS standalone, stock fuel pump. I dont want to mess with a FPR if I dont need one right away, so im wondering how much boost I can safely run with stock fuel pump and 460's and no other fuel modifications.
sorry if this has been covered, couldnt really find an answer by searching
any insight greatly appreciated
sorry if this has been covered, couldnt really find an answer by searching
any insight greatly appreciated
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The stock fuel pump is the kicker - it could tap out at 180whp or 240whp. You should replace it with a Walbro 190.
Walbro 190 pump and Rx7 460s are good for ~230whp on an otherwise stock fuel system.
Walbro 190 pump and Rx7 460s are good for ~230whp on an otherwise stock fuel system.
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so if i look at the last table, assuming my pressure will remain at 43.5, and i managed to get 200hp, and my bsfc is .65 (upper range) with this over estimation, i would only need 430cc injectors. I guess I was looking at it as the injectors need to be able to keep up with the airflow, not with a horsepower range, but i guess since the horse power is controlled in part by intake pressures, that kinda makes sense.
either way, seems 460's are good for around 200hp, and im not aiming that high yet, so maybe ill just stick with the gt25 at 8psi? im worried gt28 with 14.5psi actuator might be pushing my luck?
either way, seems 460's are good for around 200hp, and im not aiming that high yet, so maybe ill just stick with the gt25 at 8psi? im worried gt28 with 14.5psi actuator might be pushing my luck?
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looks like ill be adding a walbro 190 to my list. main question was really to try to help me decide which turbo to go with, I mostly auto-x so I want something that will spool as quick as possible, but also give me some headroom. I didnt wanna go too big for the injectors I purchased either tho. im thinking gt25 because it should spool pretty quick, but I feel like a gt28 would still spool pretty quick and give me more headroom, the fact it comes with a 14.5psi actuator is just what scared me. I wanted to start small and work my way up, but dont want to buy two turbos in the process, i guess ill just look into a smaller actuator for the gt28 to start me out with
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