Fuel Injector Flow Rate

[DEcosse]

What is the spec flow rate of the OEM Fuel Injectors?
What are you FI guys using - what max HP are the OEM good for?

 

[IMFASTTOO]

What is the spec flow rate of the OEM Fuel Injectors?
What are you FI guys using - what max HP are the OEM good for?

Weve made over 245 HP using the stock injectors

 

[ruzzle]

Someone did a bench test on the OEM injectors a little while back and got static flows of around 330 ccs/min at 3 bar fuel pressure.

The injectors are unbranded and who knows where Triumph source them?

They seem to be good enough at high duty cycles for around 230-240 RWHP.

Beyond that, Siemens Deka make a 630cc/60 lbs/hr unit P/no. 107962 which will provide for RWHPs up into the mid-300s at sensible duty cycles. It's about the only stubby injector available in an appropriate size and is a straight physical swap.

All the "calculation tables" on the web generally tend to over-specify.

 

[HansO]

Someone did a bench test on the OEM injectors a little while back and got static flows of around 330 ccs/min at 3 bar fuel pressure.

The injectors are unbranded and who knows where Triumph source them?

They seem to be good enough at high duty cycles for around 230-240 RWHP.

Beyond that, Siemens Deka make a 630cc/60 lbs/hr unit P/no. 107962 which will provide for RWHPs up into the mid-300s at sensible duty cycles. It's about the only stubby injector available in an appropriate size and is a straight physical swap.

All the "calculation tables" on the web generally tend to over-specify.

They are made by Bosch and are made especially for Triumph and are only available thru a Triumph dealer so they can stich you up, similar (but not the same) Bosch injectors are near half the price

 

[DEcosse]

Weve made over 245 HP using the stock injectors

Someone did a bench test on the OEM injectors a little while back and got static flows of around 330 ccs/min at 3 bar fuel pressure..

Hmmm ..... per all the calculators, you would need at least 535 for 245hp normally aspirated and that goes up to 643 for forced induction
(even taking away the 80% limitation, that still only gets you to 428 and 515 respectively

RC Fuel Injection

What am I missing with regard to these numbers? (at least the 330 suggestion)
Running at 80% duty, those should only be good for ~ 150 HP (or if that 330 flow WAS at 80%, then it would be 190 hp)

 

[ruzzle]

Bench tests/static flow ratings are at 100% - injector held open - and these were at OEM fuel pressure 3 bar.

Dunno what "you're missing" but as I said, web calculators always seem to over-specify.

As you can see, there are MANY Rockets gadding about on OEMs with up to 230-240 RWHP. TTS supply the 630s with their blower kits and that injector is used by all of the (few) people I know who are in the 300+ range (with one notable exception who has ventured into the 400 area.)

These latter bikes are mostly forced air and thus would be running higher fuel pressure... 4 bar......or more.....

Siemens Deka also supply one other "stubby" injector at 840cc/80 lbs/hr which is virtually a straight physical swap. The calculators will tell you that you need this at around the 300 level. You don't.

I discovered this last fact after I bought the blu**dy things.......

 

[Neville Lush]

A rocket will run out of fuel from the pump supply before the injectors are too small. Stock pump is good for approx 240hp at the rear tyre give or take a bit, under full load. A lot of injectors on paper are rated at 4 bar (60psi) not 3 bar so one has to be careful to do correct comparisons. I did not read your link to RC eng as I know this from personal testing. The siemens ones Ruzz speaks of are good for over 110 hp/cylinder on a forced induction motor at 4 bar. In my opinion they are too large for all but the hottest R3 and they don't have a great pattern for the inlet design of the R3.

 

[Tripps]

I know Carpenter changed the fuel pump when he did my 240 hp motor, and I think, but can't remember for sure, that he changes the injectors, too.

 

[warp9.9]

I know Carpenter changed the fuel pump when he did my 240 hp motor, and I think, but can't remember for sure, that he changes the injectors, too.

No bud he uses the OEM ones. Granted they are maxed out though.

 

[IMFASTTOO]

No bud he uses the OEM ones. Granted they are maxed out though.

HE has tried the bigger injectors and produced the same HP but he does use the larger ones on the 265 package