anthonyjmarshal

I have a changed my 350 tpi to holley stealth ram intake with vortec heads. I also put in 36 lb injectors and cam. I am using an apu1 tuner from moates. I also have a wide band o2 sensor and gauge.

Basically I was trying to change my fuel pulse width for the new changes. The car does run, it idle kinda rough. (The car sometimes gets to a point when the car runs so bad when its warmer it dies when stepping on the pedal) The biggest issue is no matter how much I change the tables it makes no difference. I turned off the calculate fuel flag. I also do not have any check engine light on.

It was running decent when it first starts but then the o2 gauge shows it runs super lean at idle but the computer is telling me its running super rich. I am very confused and changing the bpw is not making any difference.

I am using tunerpro rt v5, 32b.xdf, 165_160.ads

If anyone can help it is much appreciated. (I am newish to tuning)

RBob

iTrader: (1)

I'm not very familiar with tuning the MAF set ups via the PW tables (I don't do much MAF tuning). So I can't really help in that area.

However, hit the Tuning Guide Book sticky up top, in Chapter 5 under the '7165 ECM there are a bunch of threads that will help. IIRC, funstick has a thread where he goes into detail on tuning via the PW tables.

The MAF Miscellanea thread touches on a bunch of topics concerning how varies functions in the MAF code works.

RBob.

red rock

iTrader: (2)

I don't know anything about tuning, but I'm just curious as to why you went way up to 36 lb injectors?

anthonyjmarshal

I had the original 19lb injectors from the 85 tpi. I figured since I upgraded cam, headers, stealth ram intake, and 98 vortec heads the little injectors would be lean on the top end and could not supply enough fuel. They were also pretty old and had a higher chance of failure.

I went with 36lb since I knew it would give me a little wiggle room in case later I upgrade and make some more power. I also wouldn't have max out the duty cycle to keep the engine from running lean.

As for the post. I switched from the 32b.xdf mask to the 6e.xdf mask. I am still learning but for some reason it works better.

Ronny

iTrader: (1)

I may be the combustion is not clean or stoich. 02 sensor reads unburned 02. Filthy rich has a lot of unburned. 02 may read that.

How big is cam? Is there a constant or flag for open loop idle in 32B?

anthonyjmarshal

I figured it out. The wide band o2 I was using was on the wrong setting. It was 0-5v. I had to switch it's settings to 0-1v. With the wrong settings it would automatically max out the o2 reading to the computer make it think it was running super rich and therfore it would lean the car out like crazy.

The cam is not to big it is 221/221 at .5 110lsa.

As for the pulse width table I gave up on that 32b.xdf and went to the 6e.xdf and just messed with the mac tables. The car is running a lot better now.

84Elky

Am using a roller 217/225 .495/.500 110lsa 54deg OL in a 350 TPI SD, not MAF. Runs and idles great. If you can tune, almost any cam can be made to work. Many here running much more radical cams with TPI. Like RBob, I'm not that familiar with MAF tuning so no help; but as Red Rock implied, 36# injectors might be overkill with your setup. Seems they would be harder to control at idle than if smaller. Might try running some theoretical calculations for max injector sizing (start here: http://www.wallaceracing.com/Calculators.htm). Also, wouild look at idle BPW. If < 2.0ms that could affect idle.

anthonyjmarshal

Thanks for the input. I figured out how to tune the car. Now it runs amazing. It was not getting enough fuel at idle so it was running like crap. Made the cam seem huge but now it seems very mild. Throttle response is great now too. Idle is extremely stable so no more issues there even at 700 rpms.

RBob

iTrader: (1)

Going to the $6E mask was a good choice. Others that have made the switch found out the same, that the engine runs better.

RBob.

anthonyjmarshal

When I used the 32b reading information through aldl it seemed to be extremely slow and unreliable. Switching to 6E it reads so accurately and is quick to update values. Not sure what causes it but it was a massive help when trying to read data.