Most liked posts in thread: BIGGER is BETTER!!! A FAQ on the Bosch 550cc injectors for R53

Any quick search and consequent contacting of the DYNO manufactures can find some very relieving answers to many questions. The bottom line is "ANY" chassis Dyno is an excellent tool used for tuning!(not ECU tuners but actual professionals that adjust all aspects of a performance vehicle components/parts for maximum potential). All DYNO operators can set the perimeters needed for their particular application. The DYNO wars using chassis Dyno's is old hat on most all car forums and tiresome.

MYNES simply posts before and after of how they use a Chassis Dyno. It is great information if you learn and know how to read a DYNO graph. I recommend to take the time to learn how to fully read and understand a DYNO graph because you would see that some posting DYNO graphs unlike MYNES seem to "tilt" the game a bit with final results in favor of their efforts?


The only true way to measure the accurate output of an engine is with an Engine Dyno. This is as per every DYNO manufacture at least in this country. It is understandable that it is not reasonable to pull an engine from a MINI to use an Engine Dyno to measure mods. But any vendor or supplier claiming to test completed engines or individual engine parts would be offering Engine DYNO graphs showing results of those individual parts on a controlled base line engine. Without a base line engine in the real world of infinite variables true results can not be established as a repeatable norm.

On a technical "note" the use of a flow bench testing fuel injectors and the results will not change on a DYNO of any kind. In other words the injectors gets the information from the ECU and performs the same regardless of where the engine is being run. This means the injectors characteristics are the same in any engine load capacity either on a flow bench or in the engine.
The final spray pattern may vary because of combustion chambers, intake runners, piston shape, etc., etc.,etc. but the flow bench testing is conclusive.

This can be verified through any of the Performance Fuel Injector Manufactures.

 

Alright, I think we've had enough of the back and forth?

 

Thanks, so now can we keep this on topic now about 550cc injectors and not about 450cc injectors, RMW and about your tune. I wish you could advertise yourself and your vendor in a new thread. I would greatly appreciate that very much.

 

Let me try this again...

1. The bickering has to stop. I'm not above using the ban hammer.

2. Duty Cycle is a calculated result. It is a tool for use to determine if an injector size can handle the needs of an engine. It does not mean that that an injector can go over 100%, it only means that an injector as sized can be wrong for the application. It is an accepted rule of thumb that the calculated value should not exceed 80% of an injectors Duty Cycle. If when calculating the Duty Cycle you derive results that are above 80% then one should look to use a larger injector. Rocket Science it is not and why some of you keep harping on this matter I do not know.

 

Independant explaination:

Injector Duty Cycle Explained

 

do you grind off the part numbers like other vendors?

 

its been a long time since I've seen mine :lol:

 

So with your 550's, do we need a adapter for them to be used on R53's ? and do they interfere with IC at all ?

 

OK.. I agree 100%. I feel the air amount ( CFM ) allowed into the engine is determined by the Head/ Cam/ pulley ect.. and I feel that when people talk to ME about injectors, I refer them to Mynes.

Unlike installing a larger Carburetor ( yep.. those funny looking things) that also increases CFM to the engine, where you CAN go too big.. too much Air, the ECU controlling the inj. is a totally different animal!

And when you can control the amount and when the fuel is injected... then there probably ISNT any TOO BIG!! Yes?? ( Ok there probably is.. just using the idea of a 950 Carb on a 5.0 litter eng vs a 750 !!)

When the engine desires more fuel.. the ECU takes care of it!! ( and the air flow stays the same!)

Just me.............................................

Thumper

 

I think that you can have such a thing as too large an injector. If your minimum open time on an injector delivers more fuel than required, the injector would be too large for the application. There is a definite minimum that the injector can be cycled and still deliver fuel. This is why you see dual injectors in smaller engines that have large turbos of super chargers. They fire one set of injectors at idle conditions when the fuel requirements are low and then once the turbo or supercharger(s) kick in and the fuel requirements ramp up, they fire both injectors to deliver the required fuel.

 

Agree, perfect size is one that would be working somewhere towards the middle of it's operating ranges for your application.... Otherwise BMW, for cost effectiveness would just have one big injector that works on their highest output engines and merely scale them down for the lessor output applications....2 cents