merc 2.5 injectors

**HStream1** · 12-04-2021, 05:15 AM

The Keihn Pink Tipped injector comes standard on the laserInjected Motors. Its not a direct replecement. But A Modified fuel rail could be made to work on a side block injected motor.

Originally Posted by CI STV

Pardon my ignorance, but what is this “pink tip” injector that I keep hearing about? Is that a direct replacement for the Bosch 0 280 150 036?

**CI STV** · 12-04-2021, 05:17 AM

Originally Posted by HStream1

The Keihn Pink Tipped injector comes standard on the laserInjected Motors. Its not a direct replecement. But A Modified fuel rail could be made to work on a side block injected motor.

Thanks.

**HStream1** · 12-04-2021, 05:27 AM

Keihin Injector used in mercury 150/300 laser Injected engines

Click image for larger version.

Name: Keihin Injector.jpg
Views: 101
Size: 7.5 KB
ID: 497489

Bosch 0 282 150 036 used in mercury side Block injected motors

Click image for larger version.

Name: Bosch Injector Pt#.jpg
Views: 100
Size: 103.2 KB
ID: 497490

Originally Posted by CI STV

Thanks.

**CI STV** · 12-04-2021, 06:02 AM

This has me thinking. I already have an OX Performance fuel rail, which has screw in nipples for each injector hose. Maybe I can convince Alex to build the hardware needed to convert that to the Kiehin injector, if they’re considered a better injector? Yay might be a beta option for many people, actually. Are the injector wire plugs the same?

**PanRonnie** · 12-04-2021, 07:02 AM

noop you are going to need this one

Click image for larger version.

Name: te_connector.png
Views: 24
Size: 645.2 KB
ID: 497492

**HStream1** · 12-04-2021, 07:43 AM

CI STV The Connections are totally different. You could buy what Ronnie has shown or splice a Laser harness to the Brigheport, 260, 280, S
3000 Harness.

**Chaz** · 12-04-2021, 10:38 AM

Torque x RPM / 5252 will always equal HP. No matter if it's a 20,000 rpm buzz bomb or a 2500 rpm diesel , the math always works.

Keeping that in mind, as Ronnie stated (maybe in other words) Is that the highest percentage of fuel load needed is @ peak torque.
I've never met a carburetor that didn't start going rich beyond peak HP. True as the air thru the venturi slows , less fuel is drawn out of the booster. Since fuel "curves" are not flat and linear they are a compromise at best.
Looking at A.W.'s video below we see that to achieve a target A.F. ratio the V.E. table is heavy at peak torque. I think where most guys miss the tune-up is in the area of high KPA and low RPM. Guys like us with "dumb" systems can only adjust them "globally" with fuel pressure, injector size (flow rate) or fooling the system with false TPS , KPA or IAT values.
Smart systems that can single out individual cylinders and allow you to make corrections on the fly with your cell phone will always be a step ahead.

A 10,000+ rpm drag engine is a bit out of the norm, but lets go with it ..

It's torque peak is between 5 and 6000 RPM (which is where injector pulse width will be the highest) It will move enough air to make peak HP @ 8500 ish. After that it starts to fall off a cliff.
I asked a well known Pro Gas engine builder, why the %^$&&* do you torture a motor by running it up where it makes no power .. "Because it won't leave the starting line with a bigger prop" was his reply.
Since you can't "shift" an outboard to pull it back down in the power range and in drag racing you have to get what you can early in the run, it makes sense.

Pointing a finger at just the injector is a mistake. At some point RPM will float valves (reed and poppet) , tune-ups that ask for spark before a coil (or CDM's are saturated) and injectors to open before they have had a chance to close.
The way most seem to feed high RPM or multi thousand HP combo's is with either really expensive components or a pair of injectors per cylinder.

Those 410-winged sprint cars inject fuel right at the valve head. I always wondered how the fuel had a chance to stratify and/or didn't bounce off of a closed valve head and start moving up the port backwards.
Looking at this "open air" system with a large time window to break up the fuel droplets ... I wrekkon it don't really matter where ya put the fuel in ...

**Onetime** · 12-04-2021, 10:43 AM

Well said Chaz. Peak torque is max fuel requirement.
When mapping fuel curves requirements drop off after peak torque.

**PanRonnie** · 12-04-2021, 12:46 PM

Tunerstudio actually has a tool to get a fuel map loaded based upon Torque and horsepower numbers at particulair rpm
this only works for MAP load setups but it should get you going

**InjectorService** · 12-05-2021, 12:29 AM

I was wondering when Chaz would chime in. Good info, thanks. So does anyone here have info on what pulsewidths these motors would be running at say 5000RPM, or 10000RPM.

I think if choosing new injectors there are so many different factors that you would basically want to take any injectors that you are considering using and flow them side by side with a 0 280 150 036, every 1000 rpm at 25, 50, 75% duty cycle, and graph it.

I just ran a bunch of tests on my "fancy replacement" injector against an OEM Bosch hose feed and had some good results. I was hoping to post info and numbers here, but the Merc injector I was using failed near the end of my testing, so I don't trust any results.

Can someone enlighten me on tuning the Merc boxes (Brucatto or PPE). Can you add fuel where you want on those or is it only a % across the table?

Also, someone earlier was asking who can run injectors on a test bench at 10k. I can definitely do that. I can run them at whatever RPM & pulse width you want.

**InjectorService** · 12-05-2021, 12:55 AM

Here's a picture of the spray pattern on the 0 280 150 036 vs the replacement I'm working on.

**CI STV** · 12-05-2021, 08:57 AM

Originally Posted by InjectorService

Here's a picture of the spray pattern on the 0 280 150 036 vs the replacement I'm working on.

That looks like it’s doing a good job of atomizing the fuel.

**CI STV** · 12-05-2021, 09:08 AM

Originally Posted by InjectorService

I was wondering when Chaz would chime in. Good info, thanks. So does anyone here have info on what pulsewidths these motors would be running at say 5000RPM, or 10000RPM.

I think if choosing new injectors there are so many different factors that you would basically want to take any injectors that you are considering using and flow them side by side with a 0 280 150 036, every 1000 rpm at 25, 50, 75% duty cycle, and graph it.

I just ran a bunch of tests on my "fancy replacement" injector against an OEM Bosch hose feed and had some good results. I was hoping to post info and numbers here, but the Merc injector I was using failed near the end of my testing, so I don't trust any results.

Can someone enlighten me on tuning the Merc boxes (Brucatto or PPE). Can you add fuel where you want on those or is it only a % across the table?

Also, someone earlier was asking who can run injectors on a test bench at 10k. I can definitely do that. I can run them at whatever RPM & pulse width you want.

I’m pretty sure all of our motors would run like sh!t if you couldn’t at least tweak the fuel curve based on a simple speed/density algorithm (MAP/RPM).
Based on the screenshot below from Brucato’s website below, and from reading their very basic tuning manual, it’s clear that their fuel map is designed around the varying needs of each engine and (with the ACU) uses simple speed density logic to command pulse width.
I need to check to see if I can actually log injector pulse width with my AiM MXL2. There’s a bunch of ECU functions that can be read and logged through a serial connector that I have plugged into my ACU’s programming port.

Click image for larger version.

Name: 09CE1AC9-5633-41A3-A8D3-DF373985A7F1.jpg
Views: 86
Size: 399.8 KB
ID: 497556

**HStream1** · 12-05-2021, 10:32 AM

Blake: The mercury Side Block Injected ECU's are adjustable but only one adjustment in across the boars fuel percentage in 1% increments you have to use either a DDT with the correct card or a mercury 4 button DDT to make any fuel curve changes.. The Brucato ACU has 4 adjustments in various RPM ranges (Idle, midrange etc.. The Powers performance ECU Can be programed via dedicated software in a similar manner except it's WAY more user friendly than Brucato. Unless Brucato has updated its software its only supported as stated by Windows 7 which is no longer supported by Microsoft (ill stand corrected if Im wrong) The Powers ECU has a dedicated Software harness for each ECU and cannot be used on another unlike the Brucato. .

Originally Posted by InjectorService

Here's a picture of the spray pattern on the 0 280 150 036 vs the replacement I'm working on.

**PanRonnie** · 12-05-2021, 01:32 PM

Originally Posted by HStream1

Blake: The mercury Side Block Injected ECU's are adjustable but only one adjustment in across the boars fuel percentage in 1% increments you have to use either a DDT with the correct card or a mercury 4 button DDT to make any fuel curve changes.. The Brucato ACU has 4 adjustments in various RPM ranges (Idle, midrange etc.. The Powers performance ECU Can be programed via dedicated software in a similar manner except it's WAY more user friendly than Brucato. Unless Brucato has updated its software its only supported as stated by Windows 7 which is no longer supported by Microsoft (ill stand corrected if Im wrong) The Powers ECU has a dedicated Software harness for each ECU and cannot be used on another unlike the Brucato. .

Unless you have the software for it!