210 Bosch Injs

[Rob Hinson]

How hard are they to tune at low pulse widths, and are they even able to work with the software. I know on HPTuners there is a 127lb cap but you can half the inj table and double the stoich table to make larger injs work

 

[EricM]

Yes they will work, but they can take a little more time tuning. Don't expect them to hold as tight an AFR as a smaller injector at the low end.
I generally don't recommend using injectors that big unless it's really necessary, but those work ok for their size.

 

[jmidolo]

Where should I start with settings for this injector? Just swapped to them, haven't attemted to start the car yet.

 

[EricM]

Here is a place to start.

Change the injector size to 205 lb/hr, and set up the injector dead time like in the pic below. You will need to tune on the VE table and also AE.

This will get you going.

Also, set up the injector small pulsewidths like this.

 

[jmidolo]

OK, will start there...stupid question but do 205 even tho they are 210s? Thanks for the help. You going to make BG?

 

[EricM]

I forgot to mention, turn the fuel pressure down to 38-40psi. This helps with low pulse widths. That’s one reason why we’re lowering the flow rate.
I currently plan on being at BG on Friday.

 

[jmidolo]

Great...will start there..made a TON of changes to the car. I think I'm going to have way more than enough fuel...running race fuel now but have the dual hell cat pumps, went to vband housing and headers for my 68/70, external gate, CO2 etc. etc.....going to be starting from square 1. With the 210s on race fuel, I dont' think I'll even need to have the 2nd pump plugged in for now.

Unfortunately I have to leave on thursday night to fly home for daughters college graduation. Back to pick up the car the following week.

 

[jmidolo]

Down to the wire before BG, first time trying to start the car now since the changes and no start. Not sure where to begin. My hunch is it's gotta be the injectors. Any thoughts or suggestions?

 

[EricM]

Do you have fuel pressure?
On the ECU box, while cranking, you should see the injector lights come on, 3 at a time (1,2,3 then 4,5,6) back and forth.

 

[jmidolo]

42 at the rail and the lights are firing also

 

[jmidolo]

OK, got it to fire by going WOT while cracking..fired for about 5 seconds and died. Did that 2x, no fire now..making progress. Thinking it's got too much fuel. Re-cald' my TPS. Gonna go pull a plug and see what she looks like.

 

[EricM]

You may have to experiment with cranking fuel pulse. But also make sure you have the changes entered correctly that I posted above. You can send me the tune if you want, and I'll check it out.

 

[jmidolo]

Coming your way - I also added the FP and OP sensors, but haven't made those changes in setup yet..

 

[EricM]

Couple things, the injector dead time and small pulsewidth info in the pictures above, need to be entered exactly like I showed them. The top row and bottom row.

Also, put the injector size to 205 like I mentioned. You have 210. (I know the injectors are called 210's). We can always change it later if necessary.

It may not have enough cranking fuel to fire. I would increase cranking fuel pulse by about 200. Like this pic.

 

[jmidolo]

OK...will do that now. My mistake on the bottom row, figured that was the old setting. I did try both 205 and 210s. let me go back and give it a try now it's been sitting a bit and try the cranking pressure changes. Be back in 15.
.

 

[jmidolo]

No change...I did notice my MAP was only going from like 101 to 100 when cranking. I went and rechecked everything and realized I had an open port on my vac block I just installed, was planning to run the hobbs switch for pump #2 off it and haven't done that yet. I just plugged it for now. Have no other open sources. I blew into the MAP line and could see the ECU readings change so not sure how much it should bounce when cranking?

 

[EricM]

The MAP is not used for cranking fuel, only once its started. Normally it will be in the 95-100kpa range when cranking.

You could try barely cracking the throttle to see if that helps. Or maybe try lower cranking fuel.

Its going to take some experimentation.

 

[jmidolo]

The MAP is not used for cranking fuel, only once its started. Normally it will be in the 95-100kpa range when cranking.

You could try barely cracking the throttle to see if that helps. Or maybe try lower cranking fuel.

Its going to take some experimentation.

So it's about 65 here right now..if I just play with 2 cells in that table for now and increase/decrease them by say 100 each time...is that a fair change to experiment with or should I go in like 200-250 jumps? What's a way out of the range number to set to on the high or low side as starting points?

 

[EricM]

Yes that table is based on coolant temp, so you can adjust those couple cells.
Sometimes it takes a 200 change to notice a difference.
I have never made a cranking fuel table for gas with these injectors, only E85.

 

[jmidolo]

Yes that table is based on coolant temp, so you can adjust those couple cells.
Sometimes it takes a 200 change to notice a difference.
I have never made a cranking fuel table for gas with these injectors, only E85.

Yea, that was my ultimate plan for e85...but not there yet, so gas is the way for right now. If I can't get this in the next few more try, my 85s are going back in.