This may be a stupid question, but....

Can you buy too big injectors?

Just I've currently got 550cc's, and was going to get 650cc's for when I fit a new turbo and FMIC. But would there be any problems fitting 750cc's or 850cc's etc?

I understand the bigger they are, the more fuel they let through. But when it's mapped, does it matter if they are too big for the other mods? I.e, fittting 850cc's when I'm only running 400-450bhp as an example?



Thanks

 

I went from 440's to 740's with a view to future upgrades.

Providing the car is mapped properly you'll have no problems. Use an adjustable fuel pressure regulator too.

I also got better fuel economy off boost with the bigger injectors.

 

I've got a HKS FPR installed at the moment (no gauge though), and will be getting JGM to map when I have the new turbo/fmic/injectors bought.

So no problem going for 'too big' ones?

 

If you're planning some future mods get some 740's they are excellent and will be fine even if you're only running sub 400bhp.

You'll even find your off boost economy to imporve too.

Simon will sort you out.

 

Cool, thanks mate!!

 

Some people argue that its better to have smaller injectors at a high duty rate instead of larger injectors at a low rate. Theres a lot of argument floating round on the net but i suppose its down to personal preferance.

Id probably rather have the bigger injectors with good mapping, then its future proofed too.

 

Complete Rubbish!!! I'd much rather have head room.

 

Ordered some 750cc's from Area52 just now

 

Agree.

JGM mapped my 380's at 98% IDC - as variance is less than 2%. This is to realise as much bhp on them as poss, without - in theory - them ever running lean by maxing out.

However, now armed with this knowledge, if I were to aim for a certain big horsepower figure goal, I'd opt for appropriately sized injectors so as to be able to achieve that figure... BUT... at only about 90% IDC. Just to be on the safe side! You never know....