Just put a MAF TPI setup on my 355. FIrst time with TPI ever for me.

I have the 165 ECM, a stock V8 chip in it, V8 350 injectors / knock sensor. I dont have the burning hardware yet.

The motor is a Performer RPM head, XE262 Cam. I know the stock chip wont be able to come even close just from searching around this board, but...

will i be able to fire it up at least and drive it around on the stock chip?

Im also not sure about BLMS, from what Ive read they tell you how far OFF you are in (open?) loop from 14.7:1 A/F, but does it actually change your A/F to compensate or does it just tell you its off.

and is there a good starting point when i burn my first chip ever? not quite sure what im going to be doing. been running around for days now reading and im still a bit blurry. Ive tuned my commander 950 ecm though, fairly simple, is this similar?

 

The only difference from MAP to MAF is the fueling tables.
For load they use a phrase LV8, which is just the way MAF systems discribe load.

Then you have MAF TableS, vs having a VE table. If you read the sticky MAF final answer, and have any guestions just ask.

So you MAF table for timing with have on axis as LV8 with the smaller numbers being light load, and 255 max load. Whereas for MAP it would be 10-20 to 100 K/Pa.

 

<b>So you MAF table for timing with have on axis as LV8</b>

sorry i dont understand that at all...

I dont even know what the table is goina look like nor how to get to it, im waiting on the pocket programmer now.

My main concern is the stock chip and my head/cam combo. is the stock chip goina handle it for the first startup?

I would also like somone to clarify the BLM thing

 

lets keep this straight forward. stock injectors ??
in not wait till you get your chip programmer.
if there in the motor stock sized injector it should run ok for break in but the factory timing values are most likely going to be to aggresive.

 

<b>factory timing values are most likely going to be to aggresive.</b>

to aggresive? I Run 15 initial, 36 total by 2400, 50 total highway. the factory timing is more aggresive than that?

this motor is a running carbed motor right now, its getting TPI this week though and going to a TBI camaro. im busy collecting all the pieces i will need. Im just wondering if this thing is goina start with the stock chip. i suppose it should *start* but thats about it huh? since theres no MAP i dont suppose it will see my 10" Of idle vacuum huh and not flip out?

 

i doubt it but keep an ear out for pinging.

 

1) People ran around like this for years. In fact, the main methods of tuning for aftermarket performance parts were usually just an adjustable fuel pressure regulator and a good timing light.

2) How far you are off in closed loop. Closed loop uses the O2 sensor for feedback. Adjustments are made by the ECM. Problems come into effect when you are at the lower boundary for BLM (108) and the upper boundary (160?). Just as a really really general guideline for beginners, I'd say that shooting for 128 +/- 10 will at least get your feet wet. Then narrow things down from there. Good luck, -85Y

 

if the BLM adjusts in the ECM to learn how far off i am, doesnt that mean I can leave it alone since its already "learned" the proper Pulse widths? for instance in my commander 950 i run my fuel map slightly Rich so in closed loop in always off a bit, but thats ok because it likes extra fuel in open loop...

is this the same thing? Why do people shoot for perfect BLMS isnt that what the O2 sensor is for so you dont HAVE to?

 

the closer they are to within =/- 7 the better the ecm runs. its best not to tie it up with endless clockcycles of fuel trim.

 

oh so ECM speed is an issue then? running it for a while with lots of BLM corrections wont HURT anything though, will it?

when you say "run better" do you mean it will simply react quicker or what exactly changes when it runs better?

 

they AE and PE modes changes are smoother and more accurate. for a break in just take it easy and try not to run pigh rich.