I am about to expose my stupidity and I do have some questions, but first some background.

I have the EBL and am very happy with it. After some VE learns I did a wide open run and the injectors went static. I thought I had 61# injectors because that is what is supposed to be in an LO5 full size Jimmy. Therefore, I set the BPC to 124 using RBob's spreadsheet with the FP at 16 PSI.

I had it into the shop to have the valves adjusted and had them put in 68# injectors I had purchased. I asked them to flow test the old injectors and the new injectors before setting the FP.

Question 1 - The flow tests came back as 60 cc on the old injectors and 80 cc on the new injectors. This was the flow for 15 seconds at 12 PSI. This makes no sense to me because the conversion from cc's to pounds is to divide by 10.5. Can any of you make any sense of this?

Question 2 - Because the flow numbers did not make any sense I am assuming the new injectors are indeed 68#. The old injectors are not GM and I could not identify them doing an exhaustive Google search. If the new injectors are 68# a simple ratio of the flow rates suggests the old injectors flow just north of 50#. Fifty pounds at 16 PSI would actually result in a BPC of 147. What is the impact of using a BPC of 124 when it probably should have been set at 147?

Question 3 - Based on the flow tests I told them to set the pressure at 12 PSI to make a conservative increase with the bigger injectors. When I picked it up I set up a VE learn on the ride home. I was blowing more smoke than a diesel truck. When I checked the pressure it was actually at 17 PSI - way too much. I set the pressure back down to 12 PSI, but it was too late. My O2 sensor is now failing and my plugs are are covered with soot. They will have to be replaced. The EBL will not do a VE learn because of this. Any recommendations on top cleaner to clean out the engine? I have used Sea Foam down the TBI, but want to get it cleaned out before I put in the new O2 and plugs.

Question 4 - What is a good starting point for setting the injector flow by adjusting account the fuel pressure to get the final flow? The engine is an LO5 and was recently rebuilt with MSD distributor, MSD ignition, the stock heads ported, mild cam, 2" TBI, TBI spacer, intake ported to match the 2" TBI, balanced, high flow cat and no muffler (headers are next - should have been the first thing).

OK, now you can have had a good laugh at the newbie.

Thanks for your help.

 

When it was blowing black smoke, had you already changed the injector flow constant? I think just a fuel pressure change wouldn't make it smoke sooo much, but if you also had bigger injectors and higher pressure and old injector data in the calibration.........

If you did already change it =
Check to make sure they didn't tear an O-ring on the new injector install. You can do it by just priming the fuel pump (key on) and looking at the injectors - it shouldn't be spraying anything into the engine.

Also, check the spray pattern.

 

I changed the EBL bin file to reflect 68# injectors with a FP of 12 PSI when I picked it up at the shop. The actual pressure was 17#. I reset the FP to 12 PSI and changed the EBL bin, but the O2 and plugs were already covered with soot. So I will change the O2 and plugs and start over. Man! I amazed that 15 miles running such a rich mixture would cause such a mess.