ok so yay i just got my 383 running right ? right.. no first i'll list the specs of the engine..

383 full roller 10:1 compression
world s/r torqer heads
210/215ish cam about 500lift
30lb accel injectors
ported intake/superram also ported
hooker 2460 headers
msd coil/wires

well thats all nice except the car has absolutely no power above 2500rpm i'm guessing its leaning out? oh yeah this is a 1987 so its MAF

also if its leaning out above 2500rpm is it safe to drive the car normally in the 1000/2000rpm range?

now i'd like some tips on what to do to a arap.bin to get this engine to stop running so lean i was going to change the injector constant to 30lb for starters? what els do i need to do? to get it running descent not perfect?

oh yeah i'm going to be using a promulator and i'm a absolute n00b to proms etc..

 

bump

 

thank you guys for being so helpful

bought a gp1/burn adapter from moates.net used the 6e arap.bin file changed the injector to 30lb runs alot better now but it still seems lean/not making enough power... i'm going to try and increase the maf tables.. haven't bought a aldl cable yet i probably need one.. timing was also to advanced have it set at 6 degrees now

 

My advice would be to get that ALDL cable, or some type of scantool immediately. You NEED to know where you are, before you can tell what direction you need to go. Yes, people were tuning cars long before there were computers, but you'll find it's much faster and easier if you take advantage of the information available.

Second would be to spend some time reading the sticky posts, and using the search function. If you had done that, I'm sure you would have found many references to the importance of using the correct injector constant.

A lot of the basic tuning articles are written in reference to speed density rather than MAF, but they're still worth your time to read, in that the tuning process is basically the same. You'll be using MAF tables instead of VE tables, to tune the basic fuel curve, and the main spark tables are sorted by LV8 rather than MAP. There's some other differences that you'll become aware of down the road, but nothing you need to worry about at this point.

ARAP has an awful lot of timing, might want to back it off a few degrees for the time being.

Also, are you using a Prominator, or a Romulator? (they're different devices)

 

nah for the time being i'm using a gp1/burn setup from moates.

i was going to do the promulator thing eventually.. one question that would really help until i get my ALDL cable/wideband o2 sensor with the arap bin and my injector constant now adjusted to 29.4 would my engine be running lean or rich? it still has no power at cruise which i've been working on and PE adds very little to no power so i'm thinking its still lean?

i've read the articles.. obveusly i'm still confused by quite a bit

 

Without a scanner, anyone would be just guessing. The symptoms are similiar.

 

well i orderd the aldl cables.. but to get the car driveable i decreased accel enrich %bpw factor vs async pulse to 0.41 with an injector constant of 29.4 i also decreased the maxium timing from 41 to 34 degrees and that made a huge differance already

but this is just going by the "in the seat" feeling i'm sure once i get a scanner i'm going to see i'm still way off from where i need to be.

i probably would have had a much better running engine right now if i didn't go with such a large inejector from what i've read the larger injectors are harder to dial in..

 

Maybe initially, but once you get a scan tool, and get into being able to really dial things in, it'll be worth the work.

Lots of people express opinions about things they have no clues about. Hence, the bad juju associated with big injectors. But, making mor HP means being able to consume more gas, and that means bigger injectors.

BTW, my lil 4.2L, v6, uses 60 PPH injectors, is in batch fire mode and idles at 800 RPM in gear. Yes, it took some work, but not much moreso then going to 36s from 30s.

 

OK found some more problems finally plugged a scanner in basically this is what happend


BLM's pegged at 160
idle running VERY rich
o2 sensor voltage bouncing all over the place

did a quick search on the forums and concluded this is a header leak "waved my hand around the header primarys" yeah its leaking alright.. so THATS where all the power has been going..

 

bump

i'm going to fix the header leak tommorow morning and let everyone know if that fixed it..

i was wondering why i was having serious issues leaning it out the o2 sensor was screaming for more fuel since the headers were leaking..

EDIT: yup fixed now