what size injectors

[kilas4doorsleep]

Im helping a friend build a boosted d16z6 and he's looking to put out around 275. what size injectors should we use .

 

[Kensai]

Should be fine with 440cc but go with like 525cc to be safe. One thing I learned about injectors is you can never go to big. I had 780cc on my 300whp integra and they worked just fine, but If I wanted to turn the power up I didn't have to upgrade injectors. It's just the price that makes the difference.

 

[Esotericimage]

^^ what he said

 

[s_crowley 17]

550cc

 

[Faisalicious]

i have a boosted D16Z6 with 450cc and im happy with them, and what Kensai said is right, the bigger the better..

 

[TiiM iiS l3eAsT]

go with some dsm blue top injectors....they are 450cc and are good to 300whp....

 

[jhar_EK]

go to RC injectors website and they have a formula chart which will tell you what size you will need in relation to your hp goal...but like kensai said and everyone else agree it's better to have a slightly bigger injector than needed

 

[Billy.]

you're looking for 275bhp right? here's the math:

• ( [ 275hp / 4 cylinders ] x 0.62 bsfc ) / 0.80 duty cycle = 51.56 lb/hr of fuel per injector
• 51.56 lb/hr x 10.5 cc/min = 541.4CC injector size

so according to the math on the RC site you'll need 540cc or better injectors assuming you're running slightly rich and at standard fuel pressure ~44psig using less than 80% duty cycle.

for comparison, i'm using 650cc and boosted, running rich in the positive manifold pressures making about 320-330bhp at 45psig fuel pressure and around 65% duty cycle i believe

 

[Esotericimage]

Nice info billy!

 

[kilas4doorsleep]

thanx guys for all the good info. thanx for the formula lesson billy. I think were gonna go with some blue tops they seem pretty good for what we are trying to do.

 

[TiiM iiS l3eAsT]

thanx guys for all the good info. thanx for the formula lesson billy. I think were gonna go with some blue tops they seem pretty good for what we are trying to do.

good choice... blue tops are pefect for 300whp or less....

 

[toneekay]

Also take into consideration before getting the injectors. A lot of good answers above but remember if you or your friend would ever want to upgrade turbo later down the road, or even possibly turn UP the boost, it's always good to have higher flowing injectors for that extra head room.

Right now my setup only calls for 740cc injectors, that's good enough to run my turbo at 22psi @ 82-86% duty cycle. Not fully maxing out the injectors just yet, but there's a lot more room to pick up on if I were to ever decide to run, oh let's say... 26psi. These would run my injectors out to nearly 95% idc.

However, my turbo maxes out at 38psi, so if I were to EVER want to go up that high, I'd need slighty larger injectors, which is why I opted for 850cc injectors. With such a more higher flowing rate, I can run more boost on the turbo and have enough fuel to supply it. Blah blah blah. Now I know you wont run these big of injectors this soon but this'll be a good example of what can be considered.

 

[toneekay]

^Oh and that's when the formula comes into play.

 

[TiiM iiS l3eAsT]

turbo's dont max out by psi...they max out by hp ^^^^^

what turbo are you running toneekay ??

 

[toneekay]

Sorry worded it wrong; it's capable of running that psi. My turbo is rated up to 750cfm.

 

[TiiM iiS l3eAsT]

ok...but what turbo is it ??

 

[toneekay]

It's a 49lb/min turbo...........




LOL !!!!!!!!

 

[Billy.]

Life is too short to be serious, laugh it up.

wtf? SPAM!