Log Review

[Mwtvvo]

Ya, I've been considering the injectors too. I pulled some injectors from the salvage yard to see if my conditions would change, but turns out I grabbed 305 injectors instead.

I found a big problem yesterday. In an earlier post, I stated my timing was off by 12 degrees. I rechecked the timing yesterday and realized that I disconnected the wrong wire on the firewall. My 90 Chevy I had years ago was in this same area, so I didn't even think twice about disconnecting it. Yesterday I saw a second disconnect and it was brown. After disconnecting that wire and setting the timing again, the truck is running much better. Self inflicted problems are the worst.

I still need to adjust my fuel pressure a bit, but the truck feels a lot better.

The prom I'm currently using is ASDU. I believe that one is close to my setup. Why do you think it's the wrong calibration? This comment throws me off, please explain.

[tayto]

leave your fuel pressure at 13psi and get your 350 injectors cleaned. i thought you were still rinning a 305 calibration, it seems you have one more matched now, I assume you have a 700R4 and the lockup works. glad you figured out the timing. once you get fuel squared away you can probably set minimum idle if havent already.

[Mwtvvo]

Okay, that makes more sense. Yeah, it's 700r4, and the lockup does work. Finally feeling a little relieved. Thanks for your help.

[Mwtvvo]

Repost, sorry

[PlayingWithTBI]

Hi Mwtvvo, could you please publish your bins here.I have the amc304 engine in my car and would like to test these bins on it.

I happen to have an AMUS .bin file (for a '7747) but, IT IS NOT STOCK, It has a fairly aggressive timing table and, IIRC, fuel table (last modified 12/29/2018 so, I don't remember much about it). It also has the BPW and Spark Advance Hack patch. If you're interested let me know, YMMV.

[Mwtvvo]

That's interesting. I don't have a way to burn chips yet, but I will in the future if you want to shoot it my way.

Do you remember any of the mods done before creating that file?

[PlayingWithTBI]

That's interesting. I don't have a way to burn chips yet, but I will in the future if you want to shoot it my way.

Do you remember any of the mods done before creating that file?

This .bin is from when I 1st started tuning my 88 5.7L (with the help from Dave w) with a 46mm bored Throttle Body, 20LB spring, Edelbrock 3704 intake, Summit Racing aluminum heads, Lunati flat tappet 208/213 cam with fUll roller 1.6 rockers giving me .466/.484 lift and 112° LSA, shorty headers with JBA "Y" to 3" high flow cat and Borla Pro XS straight through muffler. After a few logs and tunes we decided I should go to with the much faster EBL Flash-II and a WBO2. Personally, if you can afford it, I'd go with the EBL

Like I said, IT IS NOT STOCK! USE AT YOUR OWN RISK!

[Mwtvvo]

Thanks for the .bin and the info. I will look into the EBL Flash. I'm just happy to have the truck running good for the first time since I've owned it lol.

[Mwtvvo]

Thanks for the info Tayto. I'm curious why you would recommend setting the fuel pressure by pressure and not by logging and knocks?

leave your fuel pressure at 13psi and get your 350 injectors cleaned. i thought you were still rinning a 305 calibration, it seems you have one more matched now, I assume you have a 700R4 and the lockup works. glad you figured out the timing. once you get fuel squared away you can probably set minimum idle if havent already.

[tayto]

i HIGHLY doubt your knock counts are from a rich mixture. they are either from timing, a lean condition or false knock (exhaust hitting frame, bad knock module/sensor, etc). GM's spec for fuel pressure is 9-12 psi. I have seen/felt gains on totally stock setups by putting the pressure at 13psi as that's the number these injectors were flowed at from factory. they also say thay the higher the pressure for TBI injectors the better they atomize the fuel.

[Mwtvvo]

The computer gives direct feedback on it's running condition even if it's slow. Is there no way to tune the fuel pressure by watching the computer's feedback?

[PlayingWithTBI]

The computer gives direct feedback on it's running condition even if it's slow. Is there no way to tune the fuel pressure by watching the computer's feedback?

You can look at your INT and BLM while in CL to see if you're close to 128 for an indication. O2 feedback and Cross Counts can help too. A WBO2 will give you better feedback. It's better to have known fuel pressure/injector flow 1st. Then tune INT/BLMs.

[Mwtvvo]

That makes sense. I have a spare set of 350 injectors I need to send out to have them tested/cleaned. Then I'll know those are good. I don't have a WB02 yet, but it's on my list. On my log, my injector duty cycle is pretty high.

Could that be an indication of a bad injector?
OR Is that part of the hack?
What's a normal operating range?

[tayto]

The computer gives direct feedback on it's running condition even if it's slow. Is there no way to tune the fuel pressure by watching the computer's feedback?

this is a HACK way to do things. this is what people did back in the 80s and 90s before PROM tuning had been developed. you have mixed and matched your engine and ECU and expect it to run like stock. Once you are no longer stock TUNING is required. I realize you have a "stock" 350, but we don't know what cam, pistons, etc are in it, so it is a guessing game. it sounds like it is running better than before but your calibration is NOT paired for your engine. there are also a bunch of other factors like injectors (mentioned already), general engine health (compression, worn timing chain, etc), etc etc. you can throw what ever calibration/ecu at an engine, if the engine ain't right it ain't gonna run right. period.

these injectors were meant to be ran @13 psi. can you run less pressure? yes, but they will output less fuel and usually engine performance suffers.just leave the pressure at 13 psi and move on. this is the ideal pressure for a stock application.

[badgta]

Im here to tell ya that you cannot trust "BLM" to be spot on accurate..

I just put in my new AEM 30-0300 and at idle i am at 14.x but BLM has me at 140's!!


Food for thought...