Will using an EBL allow the use of a large cam with a TBI?
Or is the restriction cause by the MAP sensor?
I think I need a cam with more overlap to bleed off low speed compresion ( too much pinging). Will the EBL allow me to do this or will I have to go carbed?
My setup:
1/2 ton truck
489 ci 10.2:1, comp 264 Hyd. roller cam. TBI @24psi. 8747 ecm

 

I am using this one, http://www.compcams.com/Technical/Se...umber=11-209-3

with an EBL in a big block. When i stepped up to this cam, i did have to upgrade the fuel pump, and go to an adjustable vac ref'd regulator. It was idleing about 35 map, now it idles about 50 map, and the EBL lets you adjust for that. The stock computer would have been hopeless.

If you do buy an EBL, let me know, I will give you a decent bin to start with.

Also, a wideband 02 is a wise purchase also, when you get this far. The ease of tuning is worth it.

 

thanks for the info.
Do you know what the cranking compression is on yours. I get about 210psi after 4 compression strokes. If I let it spin until it maxes I get about 245 psi.

 

I haven't checked it with this cam, but the last cam was a little smaller, and i got about 215 - 220 after about 3 or 4 rotations. I have different heads from stock, am using some '781 heads, for a compression ratio of 9.5:1 static. I had to run 92/93 octane with that cam, year round. This one seems a little more forgiving, bigger cam, more duration, probably less cranking compression, but as I said, I haven't checked it.

I take it that you don't have stock pistons? I had to use .250 domes, to get the compression ratio up.

 

I have 18 cc domed pistons with a 4.25" stroke crank. Brodix race-rite BB-0 heads. Should be around 10.2:1 Maybe a little higher because I had the heads trimmed a few thousands last time they were off.
I run 92-93 octane year round & have severe pinging once the temp gets above 80.

How long did it take you to get your EBL tuned?

 

Lol. Well. you can get it decently drivable pretty quick. A couple of datalogs and chips, and it will do alright. Part throttle cruise is as good now as it was stock. Idle is nice also, a little higher, 850-900 rpms, depending on temp, but its pretty solid.

WOT is where I have spent most of the time tuning. It did not help that I changed cam, and fuel pump, and went to a vac ref'd regulator in the middle of the EBL change. And I haven't even started tuning the timing tables yet.

Honestly, if you like tinkering with the program and such, the EBL, a WB 02, and a BURN1 from Moates, is the way to go.

There is a steep learning curve, but part of that is that there are so many options and tables etc, with the EBL. You don't have to change all of them, but the fact that you can makes you want to, where as with a carb you might just decide you can live with it.

I am not sure how going to a carb would solve the pinging problem. I know with the EBL you could remove timing to get around the problem, if that was the only option.

 

I could change to a rumpity rump cam & bleed off the compression.
I'd really rather keep the FI though. Drivability is so much better.