Howell vs. Affordable Fuel Injection for AMC V8

[Agar426]

Ok....I follow what you're saying, thanks for the feedback! So even with Howell knowing these specs, you still had to work with them to burn a couple extra chips to get it right?

Here are the cam specs the engine builder sent me for the 360 being built:

Adv. Dur. - 262 int/270 ex
Dur @ .050 - 218 int/224 ex
LCA - 112
.493" int/.500"ex

The CR will be 9 to 1, and it will be running an Edelbrock Performer intake. I've yet to decide on what dizzy I'm going to run, but am currently leaning toward the DUI

[Dusty]

12 chips were mailed back and forth and they were never able to tune out the dead spot in the 1400-2000 rpm range, the top end performance from 4500-5500 and the idle climb/surge issue that i had.

There system is very nice and with a stock cam or close to it in a 360 with the 350 throttle body i can not see how you will have any issues, but on a 401 i am running the larger 670 throttle body and that seemed to be where the hickup in the giddy up was. tuning, being able ti diagnose in your garage and pin point errors in the programing makes all the difference vs waiting for someone else to "try" something different

[Dusty]

if you do the GM TBI system with the 670 holley TB unit

use the ASDU bin file for the fuel tables, maps programing etc and setup. Then I had a surging idle issue and creeping idle Itried adjusting the constants in the ASDU file to prevent the system from kicking into closed loop after the cold idle sequence ended but i must have missed a switching parameter that would kick the closed loop on. So I imported the constants table from an ANUA bin file. that is the 1989 454 manual tranny ECU (ANUA 636, changed the BPW to the correct injector and fuel pressure setting. on mine it is bpw of 122 with fuel presssure at 15# and 85#/hr injectors since everything else inthe program is based around the ASDU bin but the constants table parameters from the ANUA sure brought in alot of favorable settings.

The 454 (anua) constants table does not allow the system to drop into closed loop at idle, all the settings are setup to prevent the very symptoms of idle creep and surging idle that larger tb units suffer from. Something even factory units were challenged with. so no more surging or creeping idle issues. then i just record data, tune the fuel table to work and start driving the heck out of it.