I'm looking at uprating my 550 injectors on my JDM Spec C in prep for bigger turbo. Will be looking at getting 400+bhp. Question is,,,, is there an optimum size to go for and can you go too big? for instance i know that say 650cc would be fine, but would 800cc be ok, or do problems arise by going too big?

Cheers
Andrew

 

AndyForrestPerformance

 

hi mate, i'm aware of those upgrades but does not really answer my question. thanks for the link though.

 

why would you want to fit bigger than you need?

 

Greed ! It catches up with us all sooner or later....

dunx

 

bigger sometimes is better, you can run lower duty cycle then spray pattern probs can occur if you go mad though

 

thankyou. So could i get away with 800cc injectors whilst running say,, 430bhp on a 2 litre STI?

and, to answer the above questions, why i would want bigger than needed: as Dunx as said - for future setup purposes, and because i maybe able to get a set of 800's fairly cheap.

 

800cc will give you ~80% IDC at 430bhp which is the ideal - depending on your turbo, fuel pump, FPR etc... If you're ever going to go over that bhp then get 900s and be done with it!

 

Yeah, a good rule of thumb for 'future proofing' (up to a point) is to get injectors that are c.200cc more than the minimum you actually need (this amount of 'jump' won't cause running probs).

So because 650cc will see you to 400+bhp, then 740/800cc (or even 900's) will be fine.

Then that way, you've got all that extra lovely headroom available for X-more mapped bhp (on another turbo, should it be necessary), etc..

 

Or nitrous..... oer !

dunx

 

Well you learn something new every day. Thanks very much

Cheers everyone.

 

Just to be totally clear...

Fitting bigger injectors should only be done if you are going to defo scale/map them properly... Or otherwise it will run like a bag of crap (if at all!)/invariably won't be safe for the engine/waste fuel, etc...

 

agreed