I've been thinking about purchasing a WB TT-1 from BobR although I had a few questions about the WB which I believe may be very basic, if these are answered anywhere would someone please give me the link to the post.

1. Does the orange wire (Data logger or analog input wire) need to be connected to the ECM? If so, would it replace the current NB O2 wire? or are the USBs inputs used with the WUD to calculate the VE tables for the learns?

2. Is the WB sensor used for CL operation? (This sort of ties in to my next ?)

3. Since the WB will be learning in Open Loop, what happens once done learning the AFR in OL? Would you place the ECM back to CL and run engine from there using the learned OL values for WOT and PE mode and whatever else runs OL values?

4. Is there a preferred length of placement of the sensor other than at least 3 feet after the exhaust ports, and before the cat?

 

The USB on the TT-1 is for set up via the supplied TT-1 utility (Windows based). This utility also has a large AFR gauge on one of the screens that would also use the USB interface.

Do not need to have the USB connected for the TT-1 to operate.

The orange wire (WB analog output) gets connected to one of the ADC channels on the EBL Flash board. The WUD is then set up for that channel as the WB input. It is then data logged, displayed on the main & trip displays, and can be used for VE Learns.

After learning in OL can place the ECM back into closed loop. It is best to do a final closed loop learn via the NB O2 sensor. This is due to different methods of achieving the reported AFR.

The OL areas of the tune will have been learned in via the WB, and will usually not be changed during this final CL learn session.

Other then at least 3 feet back and before a cat, the sensor tip should face downward at least a little.

RBob.

 

Do you have to disconnect the NB to learn with WB, or force open loop? Since I've reconnected the NB, the WB VE learn doesn't work. I can only learn in closed loop (NB). I'm guessing when the NB is unplugged the ECM stays in open loop and that is why you can learn with the WB?

Noob question: Is there no way for this type of ECM to use the WB the same way as in closed loop? That it could adjust fueling on the fly based on the WB input? Maybe the obvious answer is, if it could be done you would have done it a long time ago....

 

Yes, WB learning is only possible in open loop. Can set the CTS Enable Threshold for closed loop high to force open loop, or as you did disconnect the NB O2 sensor (which eventually should throw a code).

The reason for open loop is that is takes the short & long term fuel trims out of the picture.

Did the WB input to ECM for real time fueling years ago. Made me too nervous as the engine's life depended upon having the proper signal from another piece of electronics. So abandon the idea. Know of some that have melted pistons and head gaskets on boosted cars doing this.

RBob.

 

Not sure if ya ever figured it out but had a similar issue using W7 and seemed to have found a fix. If you flash READ the bin from the WUD and then begin doing the learns from the newly READ bin then it should continue saving them under .bin

 

Where do I get the EBL LO5 starting bin? I have been thinking about removing my supercharger and going basically to stock? Only mod would be the LT4 cam. I bought my EBL used with the blower so i don't have an NA starting bin?

Also Is anyone running catalytic converters? I have always heard that the DFCO and O2 settings protect the cats. Is the base EBL starting bin close enough to a factory TBI tune to keep the cats alive?

Not everyday someone asks how to slow a car down and add emissions equipment. I must be getting old.

 

What's your email ill send it through tonight.

And yes dfco is great. Mines dialed in to reach 128 BLM/int at 0%dc. Running a magnaflow high flow 3 in cat. Not cheap so I want to keep it alive as long as I can.


And that lo5 bin with some small timing adjustments and ve learns will enjoy that lt4 cam I think.

 

There should be an L05 bin wih all the included bins.

 

Thanks for the bins. I forgot to mention that I am running the older non flash ebl. Wonder if that will be an issue with those. I could always try turning off the boost stuff and starting with my current tune.

 

The Flash calibrations won't work in the Classic. You can open the Flash BIN as a compare and copy the SA and VE tables over. The EBL Classic was supplied with just the one base calibration.

RBob.

 

So I just got my WB and I thought it would hopefully cure my overheating issues as I believed my NB was giving me false info due to the huge variances between VE learns.
(Removing 10% fuel then adding some and removing the fuel between learns, ect.) Got the the point where the NB wouldn't stop removing gas in VE learns so I purchased a WBO2 because I thought the NB was bad and seemed like a good excuse to purchase a WB lol


So I just got done trying out my WB for the first time, At first the WB really started to take away gas ( more than the NB although I assumed it was normal since the WB would get to where it wants to be much faster than the NB ) and after a few learns the WB finally stopped taking away gas and it was reading about 13.7-14.3 at idle and pretty close to stoich when cruising. When I began applying the learns I noticed my temps continued to rise again

Only thing I can think of is an exhaust leak ( I know I have a slight exhaust leak where my cat is welded on which is after my WBO2 so not sure if that would be off much effect? also have the edelbrock smog legal headers with the smog tubes plugged with rubber caps although they have been like that for quite a while )...

Make a long story short, what usually causes O2 learns to keep removing fuel until engine begins to gradually overheat ?

 

An exhaust leak or some source of fresh air. I had what you describe happening on decel.
Turns out fresh air being sucked to headers from bad joint in muffler interface.

 

Wouldnt an exhaust leak/source of fresh air cause a higher amount of oxygen to be seen in the exhaust?

I was looking up some stuff and found out that a higher amount of oxygen in the exhaust would cause the O2 to read lean/over 14.7

While an O2 that is not seeing any oxygen would be reading rich/under 14.7 therefore removing fuel due to rich condition which is my problem... or do I have it switched around?

maybe I'm just overthinking it lol I'll begin a search for exhaust leaks and plug my AIR tubes on my headers really good

 

It may be time to add some spark advance. A leaner mix burns slower, so requires additional advance. Noted the 355 in the mini-sig, what heads are on the engine, and what base calibration did you start with? Or, more to the point, what SA tables are in use?

RBob.

 

I'll throw this out just in case. I had a lean engine, and it ran a bit hot(crystal white valves). I'd run the heater in the summer to help cool it down (not fun). But, when I dumped the four core copper rad and put in an aluminium two core, and a Derale fan with shroud. Day and night difference, kept the temps in check. A fan with no shroud is useless, so I discovered. I even dumped the oil cooler since, and I tought the 412 would run warmer since it's bored .060 which is at the limit of the AMC. I'm gearing up to control the fan with the EBL soon.

 

Add spark... wow lol I never thought that would be my answer but that is understandable.

My heads are procomp heads, these here:
http://www.competitionracingsupply.c...led_heads.html

I am running a tune I purchased from Harris and his tune runs pretty good but when I start to mess with the VE then it starts to overheat.

I attached a zip file with the 2 tunes.

Blackfriday.bin = Before VE learns with WBO2 (Does not overheat)
Black friday_00093 = After about 3 VE learns (overheating tune)

 

What leads me to believe that the cooling system is not to blame is because I flash the previous tune on the car and it does not overheat... when I do a few VE learns it starts to overheat with the newest changes...

Also my car only had 65k miles which I know still doesn't mean much but the fan is spinning strong and the water level is up to the top of the radiator neck... tested thermostat in a boiling pan of water and water pump has less than 5k on it.

 

I'd look at three things.
Make certain there isn't an exhaust leak.
Timing. Change fuel, and you need to change timing, which will affect fuel, which will affect timing.
That's an iterative process no matter how you slice it.
I'd want to know what is the temperature differential between the water in to the radiator vs. the water out of the radiator ?

 

A note about timing... when I went from 193 heads to Vortecs a few months ago, the truck ran different... quite a bit louder, underhood temps were quite noticeably higher, and it ran hotter, so I thought. Where is your temperature gauge? The gauge in my dash cluster said I was running hotter, but the sensor for the gauge is in the head, right between a pair of exhaust valves. I discovered that even though I thought I was fairly close on timing (I hadn't put a timing light on it right away), it installed was about 10º retarded. The truck ran like poo, but was a completely different animal after I had corrected the timing issue.

 

It seems as though I have a small exhaust leak on my passenger header. I always wondered what that small tick was for and thought it was due to a misadjusted rocker but I guess that would be my exhaust leak.

I'm wondering if that would really cause such an issue as that leak has always been ticking ever since I had the engine in the car and much tuning was done since then with the NB.

I felt all around the rest of the exhaust up until the WBO2 and I was unable to find any more exhaust leaks. I also plugged my header smog tubes with new pipe plugs and re tightened all header bolts.

I also checked my timing once the engine got up to 180-190 I disconnected the timing check wire and it was 1 degree off. I have it set to 6 on the bin and it seems to be at 5 with the timing light so I will correct that but I highly doubt 1 degree would cause the engine to overheat.

I'm wondering how I would go about adding spark to the tables as RBob suggested. I've never messed with spark before.

 

How would I find out the temperature differential between the water in to the radiator vs. the water out of the radiator ?

 

Looked at the two BINs. Not a lot of change in the VE%, some, and it doesn't appear that would be the issue.

Also, the SA looks OK too. Definitely not swirl-port tables, but more like what is to be expected for those heads. Maybe too much SA? Is the engine smooth or does it feel a little rough?

Spark plugs, not listed on the web site but odds are those heads take a 3/4" reach, flat gasket seat plug. Such as the Autolite 3924

I wonder if the engine is on the verge of overheating and the slight amount of excess fuel was enough to keep it cool. Overheating in our cars is common after a number of miles are racked up. Most common issues is a lack of air dam and/or debris build-up between the A/C condenser and the radiator.

RBob.

 

I looked at the SA tables and looks like they look a bit high. You should try bringing them down a bit. And if you are just starting out on your tune I would start conservative on the SA tables.
As for the radiator get a cheap infrared temp gauge from harbor freight and make sure its not plugged up.
http://www.harborfreight.com/non-con...ter-96451.html

 

Sorry for not posting sooner but after I had re tightened the headers and then replaced the vacuum plugs on my header smog tubes with new pipe plugs I never actually let the engine run long enough to see if it was still overheating. It no longer is overheating so that is good! Thanks for all the advise although if it starts happening again I will have to look to my cooling system as I know the tune is no longer the issue.

I was able to do a whole bunch of learns with the WB02 and wow did it make a difference. The engine will actually light up the tires now without the brakes lol

I was wondering how many WBO2 learns I would have to do before I could say the WB is finished doing its job and place the ECM back to CL.

I wish I knew how to add spark but I'm sort of intimidated on working with SA... I've been wondering what it means when someone says "add spark"
Like do they mean scale the table with a value or select a few points and just add/remove a few degrees, etc? I always felt the SA table would have to be in a wave like table. I read some of the SA threads but I didnt really get much out of them.

Also when I was doing some VE learns I noticed a "VE overflow at __ rpm/map" or something like that to the right of the VE correction tables on the whats up display. I'm assuming it just meant that the learn detected a lot of fuel correction at that location ? It was at 12%, I just cant remember where exactly the overflow point was although it was in the lower 2000 rpm range.




I know this is not related to tuning but I thought I'd post it along just to see if anyone would be able to give me a quick answer as to what the following noise might be.

Since I was able to lower down the idle some I have been hearing a pretty scary noise. I am not too familiar with engine noises but whenever the engine is idling at about 700-800 it makes a knocking type noise and you can sort of feel it in the car but not too bad. If the transmission is in neutral it goes away and it doesn't do it ALL the time or continuously... Seems to usually do it when I come to a stop for a few seconds then goes away and sometimes comes back for another few seconds... Once I start to give it some gas it will go away.

Thanks for the help.

 

> Also when I was doing some VE learns I noticed a "VE overflow at __ rpm/map"

This means that the VE table is exceeding 100%. Can lower the VE values by increasing the BPC table values. As long as the injector duty cycle is OK this is a valid way of 'centering' the VE table values.

> Since I was able to lower down the idle some I have been hearing a pretty scary noise.

Check the torque converter bolts (3), and check the flexplate for cracking. They sometimes crack in a circle around where it bolts to the crank.

RBob.

 

When it starts correcting the corrections.
In other words, you run it today, and at some point it adds 2 percent.
Tomorrow, at that same point, it takes out 1 or 3 percent.
When you're seeing that, I'd say "close enough" but that's me.
The BLM exists to compensate for weather changes, fuel blend changes, etc.
Once you see the VE Learn corrections chasing themselves, you're pretty close.
( or the BLM chasing itself back and forth. I'd call that good )

"Add spark" generally means more advance.
For me, I'll add about 2 degrees at a time until I stop seeing improvement. Then, back out 2, and let it be, absent reason to go back to it.
Ultimately, you want the LEAST advance that gives you the MOST performance and no more.
Realistically, once you get within about 4 degrees it won't matter much, if any.
Then, of course, re-run fuel learns because they will change a bit.
Logs are your friend !!
Add spark where you feel it may do some good.
For me, I'll add across the board, and take back in spots, or vice versa.
With a dist. you were limited in what you could do. With ECM, and especially EBL, the limits to what you can do are greatly removed, but along with that goes the responsibility for doing what you can intelligently.
Just because you can does not necessarily mean you should !

As Grumpy posted a few years ago, to little advance you replace fouled plugs.
Too much advance and you buy internal engine parts.
If you're seeing knock retard in the logs, go VERY slow with advance. The computer is retarding spark for a reason. If you're not seeing any at all, you can "probably" safely go a few more advance, but that doesn't mean it'll improve performance. It might, but once you get "in the zone" improvement gets really small.
The difference between perfect and 3 degrees late is something like 0.002 percent, but 3 degrees advance might put you into detonation.
Of course, the difference between 3 degrees late and 6 degrees late is more like 5 percent.

Look for anything that could mechanically knock, like exhaust pipe against the frame.
Worst case, put it in gear, pull it up against a tree ( or better, have someone hold the brake ) and crawl around listening for it.
( this in addition to what Rbob posted about the converter bolts and flex plate )

I had converter bolts hitting the inspection plate on a TH400 that did about what you describe. Couple spacer washers fixed that, but finding it wasn't fun.

 

A Harbor Freight infra red thermometer will be close enough.
Just point it at the radiator inlet, then at the outlet.
Should be several degrees different. Should be able to see the gradual change all across the radiator with no "cold" spots, or no "hot" spots.

 

Good post Cflick.

Once all the corrections are close to equal % it is perfection.

You will alway find a couple cells not aligning. I stopped using Learn to generate a new .bin. I manually adjust the one-two that are significant off from others. Seems I always hit a cell I find to not line up with its brothers. Typically over 3000rpms > 60 map.

 

Thanks for the detailed explaination! I really needed that as everytime I ask I never get the detailed response I'm looking for.

I have a question in regards to the above statement.

Since I'm going to get into spark and I have never touched my spark tables... The main thing I wanted to know was how/where to start and what you said: "add (SA) across the board", seems to be about the right place to start... and if so... can you explain how exactly you do this?

At the moment I feel like the light load and cruise areas are pretty close and if anything would need less SA as the engine starts to sound a bit rough before shifting.

Although, WOT seems as though it could use some work so would I do somthing such as add about 2 degrees across the board in the 90-100 map areas? ... or within what ranges would I do something like adding spark across the board?

At the moment I dont have any knock at WOT so I would guess doing such a thing would be ok.

I hope I'm not missing the point about this whole thing...

By adding/subtracting about 2 degrees at a specific point and looking for improvements... that seems more like the finer tuning type adjustments. (in which the logs will show such detailed corrections that would need to be made I'm guessing?)

Thanks again!

 

Depends on the editor you use.
I use TunerPro. In TunerPro, you can scale, add, multiply, individual cells, or ranges of cells, or the whole table.

Pay attention to that.
Some combinations of engine parts, fuel blend, weather, won't "knock" per se.
If it appears to be getting rough, it's possible you have too much advance, so the engine is attempting to run backwards, resulting in running rough.

90-100 MAP is typically WOT.
Also typically, at WOT detonation, too much advance, running rough, is much, much less detectable. There are only three ways I know, to know if it's "right" at WOT.
One is in cylinder pressure measurements. Probably, you don't have the equipment to do that.
Another, is top end MPH. NOT acceleration ! ( the butt-o-meter lies ! )
More power doesn't feel fast, but the ET shows that it is.
The third is MPG, which is difficult to measure for specific narrow conditions. ( and doesn't necessarily tell you the whole story anyway )

At anything less than WOT, less throttle for the same or better performance, suggests an improvement.

As above, without accurate time tickets, you won't know for sure, and too much advance doesn't necessarily result in knock, though it might.

What are you trying to achieve ?
A fast car, or best MPG, or ???
The WUD analysis screen can show you things from a log that you just can't see while you're driving.

If you're turning 6000 RPM at 140 MPH WOT and the log shows knock retard, then you know something. If the log shows lower engine temperature, you know something. If the log shows nothing, then you don't know anything, and make a best guess.
If the 1/4 mile analysis shows faster, then you know something. If the 60 foot shows slower, then you know something there.
If you've already achieved what you set out to do, then you do nothing in that range.

If your tune is far off, 2 degrees should show a noteable ( but not dramatic ) difference.
If you're close, it may show nothing.

Back in my pro-gas days, ( carburettors and crank triggers ) we would pull 3 degrees less advance above 6000 at WOT, and the only indication we had that we were doing the right thing, was higher MPH at the big end of the track. The change in ET was so small we couldn't tell anything from that, until several runs said the car was indeed faster. ( and we broke bracket )

You also should know something about combustion dynamics, where your heat sensors are, etc.
Late timing puts heat into exhaust ports, and may show burning on the headers. ( and cold spark plugs )
Early timing puts heat into cylinder heads and piston tops, but shows cooler exhaust. ( and may show hot spark plugs )
Of course, it could be the fuel blend on that particular tank, or the outside air temperature on that particular day.

If you're looking for an easy answer, there isn't one.

 

So a few weeks back I discovered how far behind I was in Tunerpro updates. I have the latest version now, but I've noticed I can't select across multiple points on any graphs... this is kind of annoying. I suppose I should look at the options but I doubt there's anything to take care of that.

 

Should be able to. Hold CTRL down as you click on each point. Can also lasso a bunch of points by clicking and dragging.

RBob.

 

That's what I typically did with the old version, it's just acting kind of weird with this version.

 

I've been more or less bypassing the click/drag method on the graph by just holding shift and selecting the cells I need with the keyboard. I've done some more learns as well, but a large part of my testing areas are already within +/-7% or so. I've also been messing with the timing, and while I think I'm at my limit above 70%map and 3500rpm, I've given it quite a bit more almost everywhere above 60%map and below 2500rpm, so far it's been responding quite well... now I can just get a solid shifting trans in there (right now it ***** pretty soft so I let off a little when it shifts... lasted me a year so far like this) we'll be good to go

 

Oh, another question I had... is there any way (or will there be a way) to run a DIS with the EBL?

 

GM DIS systems work with the EBL systems. Only issue is with the EBL Flash, it doesn't report the SA correctly. EBL P4 & SFI-6 do report the correct SA. Has to do with the -70* base timing value.

Note that it does the SA calculations and hardware programming correctly, it is just that it doesn't report the proper SA to the WUD.

Other then the N* DIS I haven't found ones for an 8 cylinder engine that is easy to come by (forget the LT5 stuff).

RBob.

 

This is my first post here. I have read this entire thread and I must say it contains a wealth of knowledge. First, background on my set up. It is a 383 with a crossfire system in a vette. It has RHS Aluminum heads (part # 12053-01) with 64cc chambers and 180cc intake runners. The pistons are Hypereutectic aluminum flat tops with +5cc piston head volume. The hydraulic non-roller cam is a Crane 114132 and has a duration at 0.5 on Int 210 and Exh 216 and a lift of Int 0.444 and Exh 0.454 running 1.6 ratio roller rockers. I have 90# injectors running a non-vac adjust regulator set to 20 psi. Running a BPC of 84. A couple questions. First, I can't get my dual TB's to balance correctly. With blades 100% closed on both I get -0.4hg on the rear (left unit) and -0.8hg on the front (right unit). When I adjust the rear up to match, the idle goes through the roof. I am 99% sure of no vacuum leaks as ALL gaskets are brand new and all Vac ports except for the MAP and new PCV were disconnected and plugged for this. Also, no EGR. There is a block off plate there. The TBs were just re-built, bored to 2" and the shafts re-bushed by a service in AZ. I have also tried carb cleaner and LP around all intake and TB areas with no change in idle. If I run them slightly out of balance with the front completely closed with the stop screw not even touching and the back open slightly I can achieve a fairly smooth idle at 700. The issue is I get 0 IAC counts and have to use SA retard to get there. SA is running at about 6 degrees. Any thoughts? Too much fuel? I would love to see a 700 rpm idle with balanced TBs with 10 to 20 counts on the IACs for better control and not have to use SA retard to achieve it. BTW they are brand new IACs too. Had the same results with the original ones though.
Second question, is it possible these heads burn very efficient? I am having to keep SA tables down in the 22 degree range to avoid knock when accelerating in the 2200 rpms range with a high MAP of 85 to 90. Base timing is set at 10 in the bin and on the timing mark with a light.
Last, I just installed and am running a TT-1 WB O2 and a new 4-wire NB O2 (Bosch 15703). The NB is usually showing a low voltage of under 200, usually under 75mv no mater what AFR the WB is reporting. The WB is doing great on learning and making the tune easy but the logs today (with that NB reading) had the INT locked at 128. It did not move even though the the WB AFR reported in the 12's to 18's at some points of the drives. Is the low NB reading and the INT not moving related or is there a different reason the INT is not moving? Most of the drive when going very steady the AFRs where in the 14's after a dozen learns.

One addition: I was idling at 950 tonight after a little more adjusting on TBs. still 0 count on the IACS. Injectors running a DC of 3% locked in Synch mode with sPW of 1.0ms.

 

I can't help with the IAC/idle speed. Can help in some other areas.

The INT won't move unless the ECM is in closed loop. Which it won't/shouldn't be when doing VE Learns via a WB.

The constant low voltage from the NB is an issue. It should switch high/low at around 14.7:1 AFR on the WB. Being a 4-wire sensor it gets wired a little differently. The two power leads are just that, +12 V IGN switched and block ground.

The signal output goes to the ECM, pin D7, same as stock.

The signal ground needs to go to either the engine block or ECM pin D6. If to the engine block then ECM pin D6 also goes to the engine block.

DC% at idle doesn't matter much. It is really for the higher RPM checking to be sure that the injectors aren't running above 85%.

Something about the SA doesn't sound right. You can get less then the base timing, but need to use either the CTS & VAC or the CTS/IAT SA compensation tables. Can't get negative relative to base via the main SA table.

Ah, can also use the "set idle SA" value. However, to get a smooth transition to off-idle the main SA should match in the area of idle.

I would also double check that the damper timing mark matches the timing pointer. GM used two different setups and mixing them up causing the SA to be off.

RBob.

 

Good info on the INT I was thinking locked at 128 was normal in a WB open loop learn but wasn't sure. As far as timing, I am set at a base of 10 because the motor starts nice there. I have the Idle State SA also set at 10 and the ECM is pulling more (not sure which table) to attain the lower idle rpm. The whole SA deal is something I am starting to work on and figure out as it is trying hard to confuse me and doing a good job right now. Currently, my headers glow red like the timing is retarded when running the motor. They get so hot they melted the condulet plastic covering off the wires that were 3" to 4" away, but I get motor ping when under power in the same rpm range. I have heard glowing headers could be lean or rich fuel, (which I am certainly rich and using VE learns to correct it) but I understand the main reason for glowing headers is retarded timing. As far as the NB O2, I will need to investigate that more. I have attached how I wired the NB and the WB. The NB has two white wires for the heater. One goes to the block and one goes to Ign. The gray wire is signal ground and goes to the block and the black wire is signal which goes to ECM D7. The ECM Signal ground is a separate wire to the block and the TT-1 is grounded to the ECM. I believe it is correct but welcome any suggestions. Also, still wondering why I can't get the idle low enough to have the IATs add steps to bring it to the desired level. Could a home ported manifold not having exactly balanced runners affect this? I was tossing around the idea of putting the stock cross fire manifold back on to test this even though I will lose significant cfm with it and have to do a different tune to support it.

Oh, and as far as the damper timing mark. When I built the motor, I set the motor at exact TBC and the timing mark did not line up with the new 400 crank balancer and the after market timing tab. While the motor was on the stand and at TDC, I etched a new mark on the damper to line up with 0*. Due to this I am 99.9% sure the new mark it is correct.

 

> I have the Idle State SA also set at 10 and the ECM is pulling more (not
> sure which table) to attain the lower idle rpm.

Most likely the idle compensation SA.

> but I understand the main reason for glowing headers is retarded timing.

This has been my experience. A lean mix does burn a little slower which can cause more heat then normal in the exhaust. But usually won't cause then to glow cherry red. Having the SA at 6* at idle doesn't help either, should be up in the 16* - 20* BTDC range.

> but I get motor ping when under power in the same rpm range.

Is it really pinging?, or is this reported from the ESC system? If reported via the ESC system it can be false knock.

Check the timing at the damper with the engine running and the ECM in control of the timing. The value shown on the WUD should match the actual at-crank timing. A distributor pickup coil that is wired backwards to the ICM will cause the SA to retard once under ECM control.

RBob.

 

Ok. Checked timing. With EST disconnected at an idle I am at 10*. Reconnect the EST and the WUD shows 6* and the timing mark is showing just between 7* and 8*. Close enough? or do I have something there? As far as ping, it is absolutely pinging as I can hear it inside the car. Attached is a snap shot of the event. Cruising about 36mph and accelerated (not to WOT) and listened to steady ping while watching SA get retarded. I running super pump gas btw. If I remember right it is 89 octane. Maybe the octane is too low for my compression. I calculate that at about 12 to 12.5:1 but since running aluminum heads I heard that would be lowered one point to 11 to 11.5:1.

 

There is quite a bit of knock retard going on. And if you are also hearing it, something isn't right. As for the compression ratio, if it is at the 12 - 12.5:1 the engine is going to require a lot more octane. The mild cam is going to build a lot of lower RPM cylinder pressure.

I used an online compression ratio calculator (www.kb-silvolite.com/calc.php?action=comp), and came up with a lower compression ratio. Using 4.030" bore, 3.75" stroke, 5cc dish, and 64 CC heads:

10.8:1 with .050" quench
11.1:1 with .040" quench
11.4:1 with .030" quench

Quench being deck height & head gasket thickness. And used 4.030" as the head gasket bore.

Now if I misinterpreted the 5cc on the piston and is really a dome, that engine will require 100+ octane fuel.

> Reconnect the EST and the WUD shows 6* and the timing mark is showing
> just between 7* and 8*. Close enough? or do I have something there?

Going up to 8* is a bit much. If you said between 6* & 7* then OK. Maybe run the entire low speed SA table & idle SA at a set value across the board, say 15* BTDC, and see if that turns out as 15* at the crank.

RBob.

 

Thanks RBob. Brain cramp. Forgot to add Quench to the calculation. I can only guess at that since I did not deck the motor and I am running the thick head gaskets and never measured it. I would guess I am at 0.50". When I do a calculation on the Dynamic Compression ratio (http://www.wallaceracing.com/dynamic-cr.php) based on 383 bore/stroke and 5.56" long rods with a cam that has a ADBC of 34 at 1400 feet, I come up with 9.95:1 Dynamic Ratio. If I am right, I still need to find a station that sells 92 octane gas. I will try that before going further. Also, can't I go to a cam with a larger ABDC # to reduce the dynamic compression and be in better shape? I was looking at the Edelbrock 7102. It has a ABDC of 44. The lobe seperation is 112* versus my 117* and I read that is harder to tune on a TBI. I am not sure I am ready to take the leap into a harder tune yet. As far as the NB O2 goes. I wonder if the heater in the thing is working. It is after the collector on full length headers. It is brand new so I haven't seen how it reacts in the summer. Right now it is in the 30's here in MN. I only took the Fiberglass Boat Anchor (Vette) out for a couple days to check the new TT-1 and saw this low voltage with the new NB. With the cold weather, and being so far down the pipe, I need to check that the heater is working. It has registered up to 900mv but only for short periods of time. I only have a day, maybe two, left to drive before snow flys and the toy is parked until spring so nose to the grind stone for a couple more days to gather data to pour over to get through the winter.

 

I'll admit a lack of familiarity with this crossfire manifold thingy, so did a little research.
It appears it's equal length runners to all 8 cylinders on top of a rather large plenum, with dual single bore TBI units ?

Sounds like your TBI units are worn and leaking air ! ( since it appears they both dump into the same plenum )

If it was me....
They make a motorcycle manometer that's fairly cheap. I used to have one. They are used for balancing carbs on the old British bikes for sure, and probably most others. Try and borrow one from a bike shop. They don't give an absolute measure of any kind. Just used for "more" or "less" balancing, which sounds like exactly what you want.
Now, get the thing to idle with zero IAC counts, and all of the throttle blades completely closed. Set the manometer on top of the TBI units and compare flow.

 

As for balancing the TB's on the Xfire, I hope you are first disconnecting the IACs. Frankly, I didn't use a manometer. I used a vacuum gauge attached to the idle port. IIRC, Grumpy would simply take a piece of paper (.002") and make certain each blade had the same drag. The other part of the procedure was to make certain the front TB throttle was "backed off" before adjusting the rear TB. IOW, the front blade needs to be completely shut. You set idle vacuum with the rear, then balance the front. Once balanced, you drop the overall idle by adjusting the main idle adjustment. All this is done with IACs disconnected.

 

>>It appears it's equal length runners to all 8 cylinders on top of a rather large plenum, with dual single bore TBI units ?

Yes, exactly. That is why I am baffled at the moment. I had the IACs set at 0 and unplugged and these TBs where bored and completely rebuilt with new shafts and bushings. As of now, I have parked the car for the winter and tore the motor down to see if I could find some root causes to my woes. I found some disturbing things. No need to diluted this tuning thread with that, but I did find a possible leaking gasket on my brand new EGR block off plate gasket that is right next to the front TB. I will continue to chase when I get all the parts back and get it running in the garage again. I want to take this opportunity to thank everyone here again for all the knowledge I gained from reading this and other threads here at TGO. I made bigger leaps forward in the tune in the couple weeks I tuned before the tear down than I did in the full summer of playing with the tune because of the info in the posts here. I wish I would have found this site when I started a year ago.

 

Not meaning to interrupt the current discussion but I am currently having an issue with my supercharged tbi setup. i am having a lag between 2-3k rpm and it seems to be across most of the kpa range. i have tried playing with timing in those areas and fuel in those areas but nothing seems to fix it. here is my sa and ve table. its driving my crazy lol.

 

Lag? What exactly is happening, how are you getting it? Throttle position, MAP readings, etc.?

 

It's more of a bog I guess u can say. Basically what happens is if I am cruising and I give it part throttle, say about 20% tps it will bog down and the rpms will drop
slightly for a few seconds then the car will eventually start to pick up and accelerate. It only happens in the 2-3k rpm range and I've had it happen at 40 map all the way up to 90 map. if I give it more gas when it bogs it will go away and accelerate but if I just want to keep it steady it will bog.

 

Added 20% fuel across my ve table and it seemed to make the bog less noticeable and less drastic. I also did a wot run and saw my dc spike at 99% which isn't good. I may need to inrease my fuel pressure a few lbs. What do u guys think?

looks to be lack of fuel When it bogs the o2 sensor dives to near 0 and then comes right back up when the it starts to accelerate. added a little more fuel to the higher kpa range and it's still hitting 100% dc at wot. I am currently at 24psi with 80lb injectors.

Ok discovered that my fuel pressure is not steady when I got home to check the pressure it was at around 20 but at work when I checked it was at 24. I think the regulator I have is junk as it is not aeromotive it's an eBay special. I never had an issue with fuel pressure when I had my cfm tech regulator so I think the regulator is part of the issue.