New Member here

[olbap]

Hello everyone,
id like to introduce myself, just subscribed to the list. 
I spent about a week reading your archives and was impressed, not only at
the wealth of knowledge but also that there seem to be plenty if not the
majority of you that are TBI fans and gurus. I was psyched! Im running a
combination that I thought was a little unusual till I saw what some of you
guys are doing. The car is an 89 Firebird (pic:
http://www.geocities.com/pipeline/6249/crosslace.jpg  )
the mods and specs are as follows:
305 .030 over (310 ci)
1 11/16 GM TBI unit with all the mods that I detailed in the
www.thirdgen.org ultimate TBI articles
Turbocity TBI to 4bbl manifold adapter
Edelbrock Torker II single plane intake manifold
'86 #416 305 H.O. Cyl heads, fully ported and exhausts polished, crane
springs & retainers
S.S.I. Flat tappet camshaft 214/224 at .050   .444/.465  112 LSA
Crane 1.6 ratio rockers elevate lift to .474/.498
Milodon Crankshaft wiper
Edelbrock TES full exhaust
no cat
no a.i.r. pump or a.i.r. equiptment
no e.g.r.  (yes i get 32 but its just an annoyance)
non drop base 14x3 open element with K&N 
accel coil (this one broke the camels back)
stock 700r4 and stock torque converter  
and 2.73 posi (converter is being swapped for 2500 stall and gears will be
3.73 soon)

Pic of the motor: www.geocities.com/pipeline/6249/DSC0001.jpg

and drum roll please.... on the STOCK GM Lo3 chip! In the stock  #746 ecm (i
think)
and it actually runs! Decently I might add. 

The base timing however needs to be somewhere north of 15 degrees or it runs
like total doodoo with random and frequent intake backfires, usually the
result off idle rapid throttle opening.
In addition it doesnt seem to rev to the rpm range one would think the combo
was good for. I was expecting 5700 rpms but it seems to kinda just go flat
at 5000 which is something ive been  struggling with.
Fuel pressure is at 14 psi, DMM o2 readings are about right on at WOT except
the faster I go the richer they are for some odd reason (faster as in
vehicle speed not engine speed)

I dont have a vacuum gauge but idle return voltage from the MAP is around
1.3. I suspect the conclusion the ECM is drawing is that low vacuum+low
rpm=heavy load so the timing is retarded as a precautionary measure thats
why i have to run so much base timing. I've tried a 100kohm potentiometer on
the map return line in an attempt to knock down the voltage some. The only
difference I notice with it is when it is adjusted to any real measureable
degree, it gives me a bad stumble/ off idle lean.  I dont know what the car
is doing at 3600 when im supposed to be at full advance. From what I
understand this ecm doesnt show advance curves either.

Im happy my single plane+Tbi experiment worked out as planned. Even with the
big cam, ported heads, and SINGLE PLANE intake manifold on a 305 with stock
converter and crap gears i can lay two stripes of 245/50 falken rubber for
20 feet or so.. 
No vacuum signal to worry about, no soggy low end :)
 Testing at the local street race spot with the quarter mile marked off
shows me doing 97 mph crossing the line which i thought wasnt bad
considering im stuck below 5000

Obviously I want to make this combo work and am a diy kind of guy. So I've
been doing a bit of research, the cheapest eprom burner I've found is the
pb-10 at www.needhams.com  as for erasers I havent looked around that much.
I also like the software at www.tunercat.com, it seems to be very user
friendly but you could probably do alot more with the freeware progs. on
this site I imagine. It also looks like I'm going to have to upgrade to the
truck ecm.
Any suggestions on equiptment or anything else would be great, and I'm glad
to be a part of your discussion group now.

My goal is 13.7 in the quarter mile

Best Regards,
Pablo Morales

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