LSJ spraypattern test

Today we did some testing with the LSJ injectors Peter has been running on his Speedster. Everything seems to work ok, except certain warm start conditions. So just to make sure there isn’t a subtle problem with the injectors we decided to put them on the preliminary testbench and get some results.

First we marked all the injectors, so we could reference them. Peter’s current LSJ’s got numbered 5 through 8, and we got another set of LSJ’s we numbered 9 through 12.

So we put the injectors on the fuelrail. First add some grease.

Slide the injectors in.

And we’re ready to go.

First we did some flow testing.

The results are in the table below.

Injector	Resistance	Fuel pressuer	Voltage	RPM	Dutycycle	Test time	Volume	Floc cc/min
5	12.0	3.8	13.8	800	15%	149	94.0	252.3
		3.8	13.8	800	100%	10	64.0	384.0
		3.8	13.8	800	100%	14	89.0	381.4
6	12.0	3.8	13.8	800	15%	149	95.0	255.0
		3.8	13.8	800	100%	10	65.0	390.0
		3.8	13.8	800	100%	14	92.0	394.3
7	12.0	3.8	13.8	800	15%	149	92.0	247.0
		3.8	13.8	800	100%	10	63.0	378.0
		3.8	13.8	800	100%	14	89.0	381.4
8	11.9	3.8	13.8	800	15%	149	96.0	257.7
		3.8	13.8	800	100%	10	65.0	390.0
		3.8	13.8	800	100%	14	91.0	390.0
9	11.9	3.8	13.8	800	15%	149	95.5	256.4
		3.8	13.8	800	100%	10	64.5	387.0
		3.8	13.8	800	100%	14	91.0	390.0
10	11.9	3.8	13.8	800	15%	149	95.0	255.0
		3.8	13.8	800	100%	10	64.5	387.0
		3.8	13.8	800	100%	14	91.0	390.0
11	11.9	3.8	13.8	800	15%	149	96.0	257.7
		3.8	13.8	800	100%	10	64.0	384.0
		3.8	13.8	800	100%	14	90.0	385.7
12	12.1	3.8	13.8	800	15%	149	96.0	257.7
		3.8	13.8	800	100%	10	65.0	390.0
		3.8	13.8	800	100%	14	92.0	394.3

Not too many strange values. But it is clear the second set of injectors is better matched.

Next, we did some visual inspection of the spray pattern. This was very interesting.

Injector 5:

Injector 6:

Injector 7:

Injector 8:

Injector 9:

Injector 10:

Injector 11:

Injector 12:

As you can see the spray patterns for injector 5 and 7 are not that great. The second set (9 through 12) look a lot more consistent.

We’re now going to try with the second set of injectors, and see if that makes a difference.