I am planning to run my gsr at about 8psi
what injector size shoudl I use? Ive used many formulas and they all tell me that the safest thing to go with is 550 cc/min, but many people here seem to use 440s. any input?

 

dsm 440's should be good

 

ok, cool, thanks!
anyone else want to chime in?


btw, I dont know much about dsm and fitment issues. On my GSR, what specific dsm 440s would fit and what woudl I have to do to make them work?

 

8 psi on a GSR with a good sized turbo and 91 gas should be around 275ish WHP. The 440's will be cutting it close.

Going with 550's will be a little safer. The price difference isnt even that much...some places even sell RC eng 440's and 550's at the same price. So why not just get the 550's?

EDIT unless of course you are thinking about used DSM's 440/450's vs RC or some other 550's.

 

go w/ 550's..the 440's will work but your not going to stop at 8 psi

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 12SEC CIV &raquo;</TD></TR><TR><TD CLASS="quote">go w/ 550's..the 440's will work but your not going to stop at 8 psi </TD></TR></TABLE>

Go with the 550's or you will be selling the 440's soon.

 

550s will be ok under 330 whp....

 

if I got RC 550s would there be fitment issues with my GSR? would i have to mod anything?
thanks (i'm not really that knowledgeable in this field)

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by b18-c-rx &raquo;</TD></TR><TR><TD CLASS="quote">if I got RC 550s would there be fitment issues with my GSR? would i have to mod anything?
thanks (i'm not really that knowledgeable in this field)</TD></TR></TABLE>

nope, they will go right in and you won't have to use a resistor box like you would if you chose the DSM's. RC 550's

 

my xs engineering kit came with 550's.....in my mind maybe a little overkill....but it doesnt hurt to buy now so when you can utilize the full capacity of the injector you can....no fault in running not to full capacity

 

275 whp on a stock gsr runnin 8psi ? I dont know about that. Rule of thumb is take the injector size and divide by 5 which would be 350 hp. Plus if you are using a VAFC to tune you can lean them out . With 550's you cant

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by mademan2723 &raquo;</TD></TR><TR><TD CLASS="quote">275 whp on a stock gsr runnin 8psi ? I dont know about that. </TD></TR></TABLE>

http://www.importreview.com/d_turbo.html

What do you think that 275 is too high of an estimate? I used a high estimate because that's the smart thing to do when you are picking out injector sizes.

 

depends what ems you're gonna be using. An fmu with stock injectors with 10 psi would run rich. Im running microtech ems with stock injectors at 7 psi running super rich.

 

I would go with 550's just to be on the safe side. I have the stock 550's on my car and I put down 308 awhp on 20 psi. There is a difference between our cars of course but I have plently of fuel with my setup so you should be fine.

 

Modified by b18-c-rx at 10:42 AM 2/21/2005

 

550s are a good choice, just b/c if you ever wanted to turn it up, you have the extra fuel needed. Also the DSMs are 450..