RC 550's question...

[myastzo]

Hi guys! My 7M has finally lost it's virginity... BHG... Resurfaced head right now, but through the disassembly process found out i have an RC Racing 550's

The engine is fully stock, although it has 2,5 exhaust, Hi flow air filter, A'pexi AVC-R

So i just have couple'o questions: Will the 550's just inject more fuel than 440's? (Stock ECU)

Or i can freely put them back and they won't affect my gas mileage and A/F Ratio?

I'm confused. Not going to tune and gain HP for a couple of years, so I just want to save engine from future problems and reduce it's hunger.

What do you think? Should I sell 550's and buy 440's, Put 550's back and remain peace, or buy 440's and save 550's for the future?

Would be grateful to see answers.

Sorry for my english)))

 

[gsxr141]

if you have 550's, you need other things to go with them. i would get a set of 440's for now and save the 550's for later on.

 

[myastzo]

Thanks for the answer!) So it just overflowing fuel?

 

[TheMaxx]

It may not be overflowing fuel, but it is probably spraying more then you need. Really depends on the octane of the fuel you have available+ cfm of air your engine is moving for injector sizing. Either way it is not ideal to change from stock with out the ability to tune for it properly.

 

[IndigoMKII]

Thanks for the answer!) So it just overflowing fuel?

One easy way to figure this out, change your oil and smell it. Does it smell more like fuel than oil? Is it extremely thin/watery?

With 440's you'll notice a more mannered idle along with better acceleration and MPG.

 

[myastzo]

Thanks! It's JUST what I wanted to hear)

 

[Mikael_7m]

if your running 550's without trouble there's a possibility that you also have a lexus afm...

 

[IndigoMKII]

Easy way to check this is to measure the AFM housing, should measure roughly 2 3/4.

 

[moejoe2008]

stock is 2 and 3/4 or the lex afm is 2 and 3/4?

 

[Nick M]

Put your air flow meter next to a tape measure, and take a clear picture.

 

[Smashey]

man just looking through the afm you should be able to tell there is a space to flow unmeasured air about the size of a regular apple slice or a piece of orange lol

p.s. regular afm is 2 3/4" Lexus afm is more like 3 1/8" (just a guess)

 

[ClutchRR]

I have a lexus AFM and 550 rc injectors and im still running pig rich is it any way to adjust this im runiing 10.4 at idle

 

[Nick M]

I have a lexus AFM and 550 rc injectors and im still running pig rich is it any way to adjust this im runiing 10.4 at idle

Fix the defect. The car does not idle at 10. with those injectors and that air flow meter.

 

[ClutchRR]

So in other words its something else wrong with my car maybe a sensor or something etc.....What should it idle at with the Lexus AFM and 550 injectors. Thnks for all the help you can give me to fix this

 

[ClutchRR]

Ok so I pulled trouble codes 24, 31, and 51 any body know wht codes these are