Injector size and new regulator

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Injector size and new regulator

Postby Hockeylife on Fri Sep 04, 2009 5:57 pm

Hey there everyone, I have a '91 240sx with a red top SR20DET and I want to get some new injectors. I have some grey ones installed right now (I assume stock) and there was a high flow fuel pump installed recently. I was looking at the size of injectors available and I was thinking of going with either 450cc or 550cc. If you have any suggestions on which size I should get, that would be awesome. I am not looking for a HUGE increase in HP but I don't want to bottle neck/restrict the system either. As for the regulator, would I be able to get away with the stock, or should I get a new one?


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Re: Injector size and new regulator

Postby Nave on Wed Sep 09, 2009 4:01 am

Stockers to 440's is not worth the money unless you get them for free/cheap. The 550's will be good for most applications. I forget what they top out at for a power level but it is somewhere around low to mid 300whp. I would NOT get used injectors unless you know the person. They can be left around, get dirt in them or whatever and then you have a time bomb. If you can't afford new injectors getting them flowed is a MUST, so include it in the total price of the injectors (purchase price plus say $75 to check them). You will save yourself a lot of headaches. As far as brand goes there are several out there. Some need to have the plugs changed to fit while others plug right in. I use Saard personally. Stick with a well known brand and you should be fine. Remember you need a means to adjust the ECU to use them. There should be no need to change the fuel pressure regulator at the mid 300whp level.
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