Fastbroker, this is the note you sent me that I need clarification on.

“I started with this BIN and it needs LOTS of work, man... Especially spark table. You could get a GREAT headstart on the spark curve by making a ficticious vacuum advance distributor table that mimics the RPM and MAP levels of the 1227747 table. Just input the HEI spark advances into the MAIN SPARK TABLE and MAKE SURE that you turn the entire PE SPARK ADVANCE table to "0"'s, or 0.4... Then, agian, gotta keep going on your own. You will sheit when you compare an HEI table to the table on the ASDU. Lots more advance on the HEI and you can still go more when careful!!! It's an emissions thing. YOU MUST monitor your knock sensor CONSTANTLY and I recommend an aftermarket AUDIBLE knock indicator. It is WORTH ITS WEIGHT IN GOLD, or pistons, anyway, and worth the hundred or so bucks... Don't listen for knock by ear, it will be too late if you hear it for a long time... “

the part I don’t understand is where do you get the hei spark advance tables and why are they so different to the asdu table. I have searched the archives and the boards for hei spark tables and no cigar. What has to be done to the fuel table after altering the spark table? Do you use a scantool, I am looking at datamaster and purchasing the cable only and downloading the program. I have been doing a lot of reading since our last posting and built a binder of info for programming, I am actually understanding the terminology for programming. The other thing I want to state is this engine will have no running time before doing the prom upgrade and don’t want to have a $5000 pce of scrap so this is my concern. Everybody says, "program your own" so this is what I intend to do.

383sbc, 23deg trickflow alum.heads, comp extreme 4x4 cam cl12-235-2, headers, performer intake c/w adapter plate, stock tbi c/w 55lb injectors, no egr, no cat, dual 2.5" c/w flowmasters, 10.2:1 comp. Adjustable regulator, stock fuel pump.

 

i was hoping to get a response.

 

Sorry, didn't see the post.

I made my oown HEI spark curve in an Excel spreadsheet. have fun

[This message has been edited by FastBroker (edited June 04, 2001).]

 

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[This message has been edited by FastBroker (edited June 04, 2001).]

 

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[This message has been edited by FastBroker (edited June 04, 2001).]

 

FB, how much of a differance did you see by changing your spark tables and did you notice any differance when you turned your egr off.

One other question, why did you take out your LT4 hot cam, did it not run well with the tbi setup?

Steve

 

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[This message has been edited by FastBroker (edited June 04, 2001).]

 

I'm also going to use the LT4 hot cam kit in a 96 350 Vortec but I don't have the hardware to tune the chip or turn off the egr advance. I would like to get into prom burning but I don't have the equipment, and after I finish the engine building I won't have the money. Which came first the chip burner or the egg, I mean engine. Go figger. Anyways I guess I'll have to run a tight quinch, polish and coat the combustion chambers and piston tops and hope for the best. I think that will help a lot as well as make for a more effiecent engine.

Steve

 

i just logged onto the site and found the your reply. thank you for your time, i really appreciate the info. i have to big chevy trucks, one with a 350 and original tbi and prom, and the other is the 383 which just picked up all the parts, lots of bucks. would you contact me by email so i can ask you something without having to wait for a board response. i figured you were just missing my note. again thanks for the curve.

 

FB, I forgot to ask what size engine are you running and what size injectors is on you tbi. i was going to use my stock 55lb units but stay away from wot until i break the engine in. you run with no egr correct!

 

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[This message has been edited by FastBroker (edited June 04, 2001).]

 

do you have to block the vaccum lines to the egr or disconnect anything to the egr, or will the eprom change just take care of things?

 

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[This message has been edited by FastBroker (edited June 04, 2001).]

 

what did you do for egr valves on the ecm constant tables, did you put everthing to "0" eg: low map egr on,(map)

i got this off the turnercat "table" menu under "ecm constants"

i would sure like to see your bin so i have something to see what changes you have made this would help me big time. i have a 1987 chev offroad 4x4, 350tbi, 35"rubber, 700r4, headers and dual exhaust, lockers front and rear, 4:11gears, performer camshaft.

 

That thing must go ok, PRscarf.

Somewhere in here I posted my EGR stuff. Search under EGR in the DIY area... Market sucks too bad to talk about much today, sorry. Gotta go.

 

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[This message has been edited by FastBroker (edited June 04, 2001).]

 

fb, i finally got my new engine running and cannot seem to understand how to convert the above table numbers to degrees. i thought it was n x (90/256)? are you running your engine with higher values than the above?

also, what compression are you running with the 64cc vortecs. flattop or dish pistons?

what is your initial timing set at, "0" (ecm diconnected) the gm dealer told me "0" is factory for initial.



[This message has been edited by prscarf (edited June 02, 2001).]

 

Those are degrees so reverse the formula to see what the entries are in hex.
I wouldn't run that map on a million dollar bet. Grab a bunch of bins and look at them.

This is a classic, run as much timing as possible. In hilly terrain, you gonna beat the bottom end out of the motor. Also, the timing in over run can be much improved.

And the 747 ecm won't even see 46d timing. The distributor would be firing the next cylinder at over 45d timing, and if your running any initial you'll have even more problems.

Gads, bad, bad, bad,

 

grump, thanks, i will scrap the idea. i am presently using the timing for the stock asdu.bin. do you know of a better bin i could use instead of this one.



[This message has been edited by prscarf (edited June 03, 2001).]

 

==== on your own

[This message has been edited by FastBroker (edited June 04, 2001).]

 

Before getting too sarcastic you might think tings thru a little farther.

vac adv is used thru a ported vac source, sot at say 3,000 rpm the throttle is opened enough to be above the ported source so yo don't have any vac adv at the rpm (as an average figure).

Again as you increase the throttle opening the eng vac drops so even if your using man vac to it it does the same thing, and again it drops off alot quicker then in that table.

Try driving up a serious hill with that table, and watch you knock counts.

Dynos are need if you comparing dyno numbers, but have little to do with the real world, watch the tuners, of a pro team, even with a million hours in the dyno cell, they still check plugs ALL the TIME.

Dynos never take into account the actual under hood operating conditions, PERIOD. And they have alot to do with tuning.

 

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[This message has been edited by FastBroker (edited June 05, 2001).]