hmmmm thank you once again!! Interesting information there! Well if Cflick had it right then that wouldnt be the cause at my cold start idle situation. Still havent had the time to even pop off the dizzy cap but im still leaning on something wrong with my ignition system.

 

I've never heard about Aeromotive making a TBI AFPR..? Some are using the Aeromotive 13301 but that's a high-quality external AFPR. Imho including lines, fittings, plugs and everything else when it's said and done will run about 200 bucks. I personally prefer a stock location replacement.
Board user dctrumpet on here (tbiparts.com) would be one source to hook you up with a VRFPR to install in the stock location, along with other parts like spring or whatever you might need for TBI..

 

If your going to re-gap ur plugs, just throw in some new ones. I'd also consider a plug one step colder than what I see in pics. The ground strap should transition in color at the radius. Close to the base of the plug is too hot, close to the tip of the strap and you're too cold. Sort of like Goldilocks.

 

what will i need to do to program the ebl flash to make it work the crossfire 305?

 

I'm gonna disagree with that one Dom !

Plug heat range is determined by how far down the ceramic insulator is the soot ring.
Too close to the tip, the plugs are too cold, prone to fouling. Too far down in the housing, the plug is too hot, prone to be the cause of pre-ignition. ( fouling is an inconvenience. Pre-ignition is fatal ! )
It's more difficult today with cleaner burning fuels. The color ring may not be soot at all, depending on the gas, but you are still looking for the color transition down in the plug on the ceramic to judge spark plug heat range, on an engine that is running right.

The heat range of a spark plug is the length of ceramic between the plug tip and where the ceramic contacts the outer housing. The shorter that length, the faster the heat gets into the cylinder head. The longer that ceramic, the longer it takes for the heat to be sucked into the cylinder head, possibly longer than the time to the next firing resulting in an overheated plug tip.

The color transition on the ground strap is said to be an indicator of timing advance, but I have no personal research data to either support or deny that.
MPH at the big end of the track is the best indicator of proper advance.

 

You got it right !

Obviously, a hotter coil, and really good wires, one can run a wider gap.
Higher cylinder pressure, ( turbo, high compression ratios ) and one needs a closer gap.
High turbulence heads gets better fuel distribution in the cylinder and a faster burn, but requires a narrower gap to prevent blowing out the flame kernel.

For me, with my coil, my wires, under the conditions my engine ( normally ) runs, that's around .065.
A good indicator of a failing coil, is to close the gap down. If you get down around .010 and it starts to run OK, buy a coil. ( how do I know this ? )

Additional: A rough cold start idle that gets better with a smaller gap suggests weak ignition.

 

well today I took the car for a drive...everything was good..then I stoped for some food..for like 25 min...when I went to restart the engine...engine cranked but didn't fire, then I notice my fuel pump wasn't priming....I proceed to connect the lap top and open the wud...to check for voltage on the pump..then I realized it wouldn't link up with the computer...so next step I took the computer out thinking maybe one of the wires came loose when I installed the eblp4...but everything seemed fine...im pretty sure the ecm is gone.
question is how can I check for this?
and also I have another 7730 from a 91 tpi speed density 305...can I reinstall my eblp4 on to that ecm...or do I need one from a 350 tpi?
originally my 90 350 tpi speed density... came with the 7730.

 

Reading Spark Plugs


http://www.wallaceracing.com/plug-reading-lm.html

 

Well, I disagree, and so do most all of the spark plug manufacturers.
( actually, the manufacturers all have nothing to say about the ground strap and heat range, suggesting to me that the ground strap is irrelevant as far as heat range goes )

Not a lot of google searching will find conflicting views on this point. There are many racing pages with conflicting data, apparently authoritative examples, and the like. Partly because of this, *I* don't accept the ground strap as indicating anything definitive.

Here's a page on heat range. ( a manufacturer page, not a "racer" opinion )
http://www.ngk.com.au/spark-plugs/te...ge-explanation

Note that they ( NKG ) say nothing about the ground strap.

 

Replace the ECM.

This is why I keep an old 7747 around. It isn't an ideal tune by any means, but it will get me home, and if it does, it suggests a failure in the one I was running. If it doesn't, it suggests I should be looking elsewhere.

Occasionally, once a year or so, I'll plug in the old 7747 just to make sure that *it* still works.

 

Always good to get different points of view. One of the strengths of TGO.
Knowledgeable members.
Here's another source I used so take it for what it's worth

http://www.dragstuff.com/techarticle...ead-plugs.html

Also, if you do plug cuts as Grumpy would always recommend, the lowest part of the ceramic shows WOT, the mid-section cruise, and the tip shows idle.

 

You can use any '7730, they are all the same. Even the ones GM used for the 4-cylinder TBI engines can be used.

Does the SES/CEL turn on? If not check the inline fuse under the hood. It provides power for both the ECM and the fuel pump.

RBob.

 

sorry my ignorance rbob whats the SES/CEL?
and where is the inline fuse under the hood?
thanks

 

Service engine soon/ check engine light .. And I think he is talking about the fuse by the battery ? Not sure

91' bird 305 TBI T-5, trick flow 175 cc heads, 4.10 gears, lots of suspension upgrades. 24mpg @ 2500rpm hwy. 8.80@ 84mph 1/8th on street tires... 8.000's soon

 

yes the ses light came on....i checked the fused by the battery and it was burned
well at least was an easy fix....

 

Indeed ! More-so than any other single source I've ever found.

OTOH, a forum like this one, by their nature are full of unverified opinion, misinformation, misinformed posters, and a host of others.
I'd take anything posted ( included by me ) with a grain, and do your own followup research/confirmation.

Posts are for information only. The poster ( including me ) assumes no liability or responsibility for any consequences in the event any reader uses the information posted for any purpose.

Engineering principals and theory, physics, is one thing. "I did this and it worked for me" is something entirely different.

 

It is common for that fuse to pop for no real reason. I figure it is due to the heat and vibration at that location. It just replace it every few years.

Easy fixes are the best.

RBob.

 

what will i need to do to the ebl flash to make it work the crossfire 305? not the ham board

 

Need to replace the stock edge card ECM harness connectors with the pin type connectors. These are the connectors that are used on the TBI ECMs of the later 80's and 90's.

Can either cut and crimp on new terminals for those connectors. Or cut and splice on wires that have the terminals already on them. Such as gotten from a u-pull-it yard where the engine was cut out.

RBob.

 

no I meant the internal programming. Does it have to be altered to work for a 305 from 350 ?

 

depending on what you're shooting for and on the engine build the answer is probably: yes, maybe a lot.

 

I want use it on my stock 305 crossfire

 

There are 30-some calibrations (BINs) included with the EBL Flash system. For a 305 x-fire engine with stock heads we recommend the base TBI BIN be used. Just need to un-check the malfunction flag for the IAT 23 error, as the x-fire's don't have one.

RBob.

 

I presume you are planning on modding the engine in near future?

In the .bin is a function of engine size. You can change that if you go bigger or smaller. I have a 350. I may go to 377 in future possible next season. So I will change the constant for larger engine. Quite simple actually.

 

Very simple.
Before tuning, I was actually surprised how little had to change to move from a 350 to the 455. More mechanical than programmatic.
Most likely, just plug it in, and it'll run. Maybe not well, but probably it'll start and run.

 

Update: Well i know i only regapped my #1 plug to .035 but i noticed your final note
"If car runs better with a smaller gap, expect a bad ignition coil." Well my car is running SLIGHTLY better. Because ive been toying with this problem for awhile now i can notice it starts a little smoother on cold starts and keeps a more constant rpm with less throttle. Ignition coil hasnt been changed for 5 years, still need to check my dizzy!

So does the consensus agree that my plug looked ok though? ( i can see some disagreement going on about plugs above)

EDIT: oh and i will be putting all new plugs in rather than being a cheapo and regapping these old ones, just have been trying to hold off until my soon header swap so i can have it easy.

 

If it was me, I'd regap all the plugs to .010 or .015 and see how it idles.
If better, then consider wires, a coil, cap, and rotor, then new plugs gapped where you think they should be.

Weak ignition most often shows up under high cylinder pressure.
That means a lot of foot at low to moderate RPM, but runs fine under light load, like a moderate ( 45 MPH ) steady cruise.

 

I have a jet stage 2 computer chip for a LO3 5speedcar idk if it would work for u or no but ill take 30$ shipped

91' bird 305 TBI T-5, trick flow 175 cc heads, 4.10 gears, lots of suspension upgrades. 24mpg @ 2500rpm hwy. 8.80@ 84mph 1/8th on street tires... 8.000's soon

 

yeah a 350 crossfire later

 

Question guys. Recently set the idle for the camshaft I am running, and the IAC steps need to hover and maintain around 70 steps when warmed up, which is fine. Made a few adjustments in the bin, and now the IAC goes wide open at key on (stock bin value was way under 100 steps at power up/key on, which caused stalling when started). Now she starts right up, and transitions smoothly from idle to gear, and back to idle no problem, never falling below 70 steps unless the engine is turned off of course. However, upon restarting when hot, I noticed that the IAC steps will go right down passed the commanded 70 steps, right down to around 20 (which I'm assuming is a stock value that I missed somewhere), and the engine will stall unless I hold the gas and wait for Closed Loop to become enabled after a few seconds and make its' way back up to 70 steps. Where in the XDF am I missing an area to stop the IAC from going down that low upon hot restart...?

 

I'd like to correct a few mild issues with the 292 truck.

1. Cold start is kind of rough. Watching the wide band, it actually runs quite a bit leaner than commanded for the first minute or so, and as the WB AFR comes inline with commanded, it seems to smooth. Though, commanded also seems quite a bit leaner than I'd expect on top of it (I'd expect maybe 11:1 in choke but WUD showed 14-ish? I'll have to log it). Does the "commanded AFR" include any choke settings? What could effect a commanded vs WB differential during these conditions?

2. Prop gains appear to be too high. I didn't notice this before but at low load, like idle, or holding the RPMs just off idle in park, you can see the O2 reacting very slowly and very dramatically making AFR swings (like a whole point). What exactly should I back off to curtail this? Do I lower the prop gain multiplier vs airflow at the approximate airflow where this is occurring?

3. I still need to back off on the low RPM AE. This will just take more time. It drives well but swings very rich initially.

4. DE seems too aggressive, so I should back that off, too (swings lean on lift). I just want to see less wild WB swings than I currently do.

By the way, we got the 2-bar MAP installed. I changed the BST vs BPC table to match the 0kPa cell of the VAC vs BPC table, checked the box and whatever else. Will the Aeromotive 13301 keep pressure stable so I can use a constant BPC during boost? I know it claims it is a 1:1 pressure change during boost but can anyone verify this behavior?

Anyway, BLMs seemed to be close enough after the 2-bar install but I would like to do another WB VE learn. I saw a little odd behavior at idle with 138 BLMs...

Next thing is to wire in the IAT and get that tuned appropriately. It is already installed in the Caddy TBI air intake housing. Generically, we want less SA and a less fuel at high IAT, yes? I suppose the fuel changes are part of speed density calculations, and embodied in the CTS/IAT blend filter. Then, as a result of this composite IAT/CTS value, we can add or remove SA. That's a little confusing as it is totally different from the stock strategy I am familiar with (there is also the regular CTS comp SA vs vacuum table). Any tips with the CTS/IAT blend settings or anything else?

Looking at the calibration help file, I see a little tip actually. IAT blending is probably best at lower airflows where it will pick up more intake tract heat. Makes sense. Of course the question is, how much blending? Is 80% CTS at low airflow considered a lot?

While I'm at it, what about when we add the turbo? Skew the IAT blend back up at the other end of the airflow spectrum?

 

At key-on the IAC will go to the position defined by these two tables added together:

IAC - Powerup Init Steps
IAC - Init Position vs Baro

The Baro table usually doesn't need to be changed. The power up init steps is the one to work with.

Be aware that a too far open IAC at crank-to-start can cause a huge flair when the engine catches.

RBob.

 

I had same kind of behaviour until adjusted throttle idle screw until IAC counts were below 10 when fully warm and in closed loop.

 

That was it, and it figures it was the table right underneath IAC - Powerup Initial Steps, I kept passing it by as I searched the IAC tables. Okay, I have IAC - Max Steps set at 145, I raised IAC - Powerup Initial Steps from the original 75 steps to 145 steps, but now I put it back down to 130 steps to help reduce that flair you had mentioned, and the IAC - Initial Position vs Baro has been adjusted from the original 32 steps (75-KPA), 30 steps (85-KPA), 24 steps (95-KPA), 20 steps (105-KPA), to a much higher 82, 80, 74, 70 steps in the same KPA order. So far so good, but I will report back with any detrimental results...

Thanks RBob.

- Rob

 

In my case I would need a much larger throttle body, or to drill some holes in the stock throttle blades. I can't play with the fast idle screw because doing that throws everything for a loop. The cam I am running is very big for a 305w/TPI. Reason I know this is because we pulled the PCV vacuum hose with the engine running at idle and covered it with a finger, then slowly pulled that finger away to allow for additional air to get in, and with the vacuum line 3/4's of the way exposed, the steps finally went down to 25. But again, until I either get a bigger throttle body, or drill some holes, I am content with 70 steps because it seems to work fine by raising those two IAC tables mentioned in the post above...

 

So far so good still...

 

Ever since going to the 2-bar MAP, WB VE learns at 100kPa have been very sporadic. The cell stays yellow and rarely goes green while accelerating. Previously I was able to get solid green learns all through the RPM band at 100kPa. Can I do anything to solve this? It still learns fine at other rpm/load points.

Paul did also add an IAT, tapping into pin A on the TPS. I know the learn cell goes green when certain parameters settle (and no AE).

 

RBob, I know with the NB there is a BLM correction threshold in the XDF that is dependent on RPM setting, and although I raised that setting when I first started VE Learning, would the EBL still have corrected above that RPM setting in the XDF, regardless? Perhaps there is another correction area for the WB that needs to be raised to allow for correction? I myself have stopped correcting at this point, I just used it as a base to make corrections under 200-degrees, now I just go in and change the cells wherever needed otherwise it will always and constantly correct when I don't want it to because of the ever changing air temps...

 

Cold start log here:
http://1drv.ms/T068bF

I did add 1.5 to the choke AFR table.

WB wakes up at the 7 second mark. Notice the commanded AFR is way off from actual. Then it slowly starts to come inline, with full matching by the 58 second mark. Is this just a normally-inaccessible area of the VE table that happens to be off? Or is something else going on?

I did a 50% reduction and that seemed to help. I hope I didn't go too far. Seems like the sweet spot is basically the fastest switching possible, no? If it's too sensitive, it overshoots/undershoots (and seems to react a bit slow since it goes so far) and if it's not sensitive enough, it reacts too slow again. I seem to recall one of the things to watch is the INT bouncing around with the O2 as it switches - does that mean the gains are too high or too low? I didn't specifically look for that and I should have. Maybe I can dig around in a log.

Still working on this...I think the lower dTPS is still too rich.

I backed off the DE enleanment factor quite a bit (I had cranked it up previously).

I ended up blending 80-90% CTS (low to high airflow) and tweaked the SA table in a way that made sense to me.


We may want more IAT blending at higher airflows with the turbo, since IAT temps will drive air density pretty heavily (as opposed to CTS - it's a dry manifold). Well wait a sec. It IS a dry manifold. Should we be heavier on the IAT bias then?

Then we did a very thorough WB VE learn. So it's getting better, and I like having the IAT in the loop, even for a mild state of tune.

 

Updated IAT/CTS blend table:


I went with 15% IAT blending from 32 to 255 g/sec. I noticed when tuning in warmer air temps, when it was cooler the next day, the BLMs were a bit high, and this seemed to bring them mostly back in line.

Also, I was chasing AE again. It would go lean then rich, which was a leftover from when I was fighting with the manual trans AE. I backed off the TPS filter (raised the numbers) at operating temp, but it still went lean initially. I had an epiphany: this engine ran fine on async fuel, even though popular V8 wisdom suggests sync everything runs best. So I said, maybe async AE is what this engine/intake really wants, to get it as soon as possible. Well, that seemed to work. I didn't log it but looking at the WB, it doesn't go lean (on tip-in or stomp), and I ended up having to back off on AE quite a bit also. It still goes too rich on lighter tip in but overall, more progress!

 

During a VE Learn using the BLM method, the learn only takes place when the ECM's BLM learn is also active. Hit a MAP or RPM limit, or PE mode to stop the ECM's BLM learn, and the VE Learn also stops.

No such limits when doing a VE Learn via the WB. Only thing that will stop a WB learn is if the BLM is not 128. Which is easy to accomplish by disabling closed loop.

RBob.

 

Thanks Bob, that definitely clears everything up regarding that issue. Also, as you directed me earlier, I disabled the knock sensor, and that was definitely the issue I was having. Thought the wires might have been arcing because it was popping severely in the exhaust. Free revs so much smoother now it is freaking unreal, just need to replace the knock sensor with a good one in place of the stocker, as for some reason the stock knock sensor was not reading correctly, or just not testing correctly by the EBL-P4. I'm not even going to test the old one myself, just going to replace it with a new one and see how it does. Open to any KS p/n's.

 

kevm14, although i don't really have an input for you, thanks for sharing your progress and your approach to this. i've played a bit with CTS/IAT blending but found it very hard to dial in, so if you really made it to achieve consistency here, congratz i imagine it quite a bit harder with forced induction and the resulting impact on IAT and flow..

 

For a knock sensor, I'd use the one for a 305 TPI engine. Be sure to take a DVM to the parts store and check it's resistance before leaving with it. Between the body and center pin of connector it should be about 3.9K ohm (3900).

If it is close to 100K ohms, it is the wrong sensor.

Torque to 11 - 14 ft/lbs and good to go. Oh yea, it's in the water jacket too.

RBob.

 

Thanks. I should remind everyone that this is a 296cid Chevy inline 6 with a SBC TBI. Different beast than a V8 w/ dual plane heated intake.

 

Looking at the SA table, I think I was too conservative. Normal CTS is around 200F and normal IAT is around ambient + 5-10. So call it 95F. With the blending, that's 200 * 0.85 + 95 * 0.15 = 184.25F which is 84.5C. I should probably shift my 0d SA to the 80C point, since that's nominal operating conditions. So it was regularly pulling 4d of SA with the way I had it set, if I read this right.

 

Sweet man ... I had a 76 C10 with 250 inline6 I always wanted to build it up with all forged internals , boost it , and throw a TBI unit on there n spin it up to bout 7500 -8

91' bird 305 TBI T-5, trick flow 175 cc heads, 4.10 gears, lots of suspension upgrades......... 24mpg @ 2300rpm hwy 65mph ........ 8.63@ 85mph 1/8th on street tires... 8.000's soon

 

Paul is the owner of the truck (83 C10, flareside), and he is my father-in-law. He's retired and has the means, the time, and the interest to tinker with inline 6s. I'm handling the tuning. More info about the truck if anyone else is interested:

https://www.thirdgen.org/forums/diy-...evy-292-a.html

Wheel upgrade from TBI donor: http://forums.kevinallenmoore.com/vi...6&t=404&p=1625

Interior upgrade: http://forums.kevinallenmoore.com/vi...7&t=403&p=1624

Some turbo selection discussion: http://forums.kevinallenmoore.com/vi...4&t=397&p=1616

 

Awesome man ... U got it boosted yet

Edit: I need u come tune my car lol

91' bird 305 TBI T-5, trick flow 175 cc heads, 4.10 gears, lots of suspension upgrades......... 24mpg @ 2300rpm hwy 65mph ........ 8.63@ 85mph 1/8th on street tires... 8.000's soon

 

No but the EFI system is totally ready for boost.

2-bar MAP: check
IAT: check
Suitable fuel pump: check
Suitable vAFPR: check

The fuel pressure is already turned up in anticipation (which means the calibration is dialed in already, or mostly so). Selecting and plumbing a turbo is not going to be bolt-on by any means.

I figure the 300hp level ought to work fine with the small block TBI. If not, there are obviously upgrades available.

But I want to reiterate that EBL has been a godsend through this. Wonderful product and support, too. Paul was yelling at me that I didn't insist we buy it sooner (back when I was struggling with the 7747). But part of that was because I knew folks far greater than I had pulled off some seriously heroic things with the old ECMs. So I wanted to give it a whirl.