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EBL Tuning a 406 with XFI280 & FIRST Intake - Mechanical Issues or Tune?
Hey guys wanted to start my own thread cause I believe I am experiencing issues outside of the tune and want other opinions.
Drivetrain Specs:
First Intake, 36lbs Siemens Deka injectors, ~43lbs fuel pressure with non-leaking FPR, Edelbrock Performer RPM heads (correct length plugs used), full roller rockers 1.6 ratio with girdles, a Comp Cams XFI 280, Dyno Don headers through Loudmouth II cat-back, and a 30 over 400ci small block. Ignition is a GM or Reman. Small Cap Distributor (purchased used from TGO member years back), a MSD Dual Connector Coil and a MSD 6AL Box of unknown age, and basically new heavy duty 8.5mm sleeved plug wires cant remember brand.
Transmission is a TKO 600 with a Spec Stage 3+ Clutch.
Symptoms/Issues:
A severe miss at almost anything but WOT. It seems to idle "fine". Choppy but chalking that up to the cam. Under a moderate to heavy load it pulls fine. But light/part throttle and cruising it has a severe buck and what seems like miss. Punch it and it pulls good without the miss. I originally was thinking cam surge but this is beyond that. Especially since there are known members running this cam in smaller cubed setups without issues.
Things I have checked/tried:
Checked the FPR, recalibrated the WB and relocated to drivers side header, tried all kinds of different spark advance everything from high teens to high 30s, its currently on the rich side of things as going leaner only seems to worsen the situation, I have found what I believe to be the correct offsets for the injectors and am using those currently.
Cam wasn't degree'd when installed. Believe it has some built into the grind from my reading?
It idles in the low 50s kPA. I don't believe I am experiencing a vacuum leak but will be spraying around to the intake and throttle body to confirm that.
Ideas and things to mark off checklist:
Vacuum leak check - quick and easy check
New set of plugs - I know these aren't very old at all but will go ahead anyways. Maybe I should get colder/hotter plugs? I am running whichever ones were suggested for the heads
Firing Order and plug wires - One of those things I would kick myself for not checking and it end up being this simple.
Coil - wish I had a spare to test but might buy one anyways
Ignition control module - With this distributor being a big unknown in age and condition (bought used when converted from large cap due to clearance issues) I figure I might as well do this
Bypass MSD Box - piece of mind check to eliminate that as a issue
Thats about all I can think of off the top of my head. I will add to this list and mark which things have been checked/replaced as I go along.
If anyone has any suggestions or comments please let me know I would really appreciate the help.
Last edited by dabomb6608; 05-22-2019 at 09:24 AM.
You have a similar combo to mine with TKO. My first cam was very close to a 280XFI. 236/242 at ~600 lift on 112 LSA. I too experienced a bucking condition during steady state conditions. Especially as the outside air temp got hotter or the longer I drove. The manual transmission seemed to make it worse in that at cruise, the driveline is barely loaded and goes into and out of coast. It was a real bear going down a decline at ~50MPH and ~1800RPM. The best tune was in open loop and adding fuel and timing in the areas where the bucking occurred. Not sure if this is what you are experiencing but it sounds familiar.
The "solution" for me was a different cam. I went 227/239 at ~600 on 114LSA. Took somewhere around 10* of overlap out and made it MUCH easier to tune. Now I don't have hardly any surge or bucking and make about the same power. But the manual trans driveline does make the light load conditions fragile.
Rbob - Fuel hose is braided 6AN hose from the big hard line to the rails then to the Adjustable FPR and returning to the smaller hard line. Rest of the fuel line/system is stock. Fuel pump is a 255 walbro. Tune is setup to run Open Loop already. Here is a copy of tune I ran yesterday while attempting to get some learns while driving it. 2018-09-20 EBL_F_3006FRESHSTART_IDLSA30_00006.bin NOTE: this was actually after one learn without smoothing...
I have a bin I modified with a different SA Table I am going to try tonight. The SA Table is from a member with the same cam. It has much lower advance.
Antman - I've always been suspect of the cam. But I know of others running the same cam and they aren't reporting conditions as bad as this. Its more or less undrivable. You either have to be accelerating hard, decelerating hard, decelerating with clutch disengaged, or idling. There really isn't any in between.
The thing that gets me is I drove this car very frequently after installing the intake/exhaust/cam back in Nov. 2013. Up until probably summer of 2014. I don't ever remember it being so bad. I have to be missing something here.
Last edited by dabomb6608; 09-24-2018 at 01:30 PM.
I'll bet the braided line is CPE lined. Which over time hardens and actually starts to break down. The symptoms that you describe as it being better back in 2013 also supports what I'm about to say. One thing you can do is to put your nose to that braided hose. If it smells of fuel it needs to be changed out.
Jegs carries a SAE30R9 Viton lined hose. If the current AN hose ends are NOT the cutter type they can be reused.
The problem is fuel pressure pulsations that are no longer being dampened. I've been through this and the symptoms were identical. Even the timeline where it ran good at first, then over time got worse and worse. I swapped the lines out as the car just reeked of fuel from the lines weeping fumes.
And suddenly the engine ran better, much better as the Viton lined hose is rather soft and forgiving. The new hose was damping the fuel pulsations.
There are also fuel pulsation dampers that can be purchased and installed. Many cars run them from the factory.
... it's your timing Pat. You're at high 40's during light cruise in the 30, 40 and 50-kpa range. Running too much advance like that will result in a chugging, surging and jerking sensation at those RPM's.
Rbob - That's a very interesting theory and one I will definitely look into doing even if its just for piece of mind and preventive maintenance. It is even more interesting that you mention the pulsations. I know its been a few years since I have messed with this car. But I really don't remember at all being able to audibly hear a tapping that is rhythmic to pulsations I feel in the stainless hoses. It is definitely audible now. Fuel pressure is steady while running though and if I hot wire the pump to run before key on it sounds normal and has no pulsing.
Street Lethal - I have the same symptoms even with reduced timing if I remember correctly. I went that high out of desperation more or less to see what it would do. I am going to be running this tune SA Table to try now. It is from a member with the same cam and aluminum heads.
Pat, that SA Main Table in the picture above is much better, so Flash it in as soon as you can. You're currently at 30* Idle State, and upwards of 50* during cruise. That's way too much, and if you're running pump gas, I can assure you that is why the engine is bucking during light cruise. When you flash in that SA Main Table above, lower your Idle State down to 25* as well to match it...
Pat, that SA Main Table in the picture above is much better, so Flash it in as soon as you can. You're currently at 30* Idle State, and upwards of 50* during cruise. That's way too much, and if you're running pump gas, I can assure you that is why the engine is bucking. When you flash in that SA Main Table above, lower your Idle State down to 25* as well to match it...
- Rob
Yep, I had already changed it to the 1000 rpm 50kPA value as my commanded idle is around 900 when warm. The bin I had attached with the high SA values was based off of the 3006 bin (5.7L alum head 6 speed). I will definitely be testing out the new one this evening. I know I have tried lower SA before though and the bucking was still pretty bad. Maybe this is a case where I need to go extremely low in those areas?
Yes, many have ran the 280XFI with good results.
There are a lot of good suggestions here. If it ran good before, it likely is something that has changed/degraded over time.
One other idea. I also have added an air bleed to my system. Basically, it's a big vacuum leak routed through a filter. It let's the throttle blades close more and the IAC counts to go down. I'm not sure exactly why but it made my car idle MUCH better and drive better overall.
I run a lot of timing at cruise. 40+ at low maps. ~28 at idle.
Maybe this is a case where I need to go extremely low in those areas?
It doesn't need to be that high in those areas, just slightly more than your wot timing. Looking at your 3006 bin, it is showing low 20's in terms of spark advance being commanded in all four rows leading to and including 100-kpa (wot), so why would you need upwards of 47* degrees of timing at 30, 40 and 50-kpa during cruise running pump gas? That SA table you got from your friend will fix the surging/bucking, just make sure your air/fuel is tuned after uploading it...
It doesn't need to be that high in those areas, just slightly more than your wot timing. Looking at your 3006 bin, it is showing low 20's in terms of spark advance being commanded in all four rows leading to and including 100-kpa (wot), so why would you need upwards of 47* degrees of timing at 30, 40 and 50-kpa during cruise running pump gas? That SA table you got from your friend will fix the surging/bucking, just make sure your air/fuel is tuned after uploading it...
- Rob
I will definitely update later tonight on what happens with those changes. Will also be sure to have a datalog running as well during the test drive.
I generally run ~10* more SA at cruise than at high map. EBL adds timing for PE conditions too so bear that in mind. (depending on your overall tune)
I have PE mode shut off due to running this as a open loop tune. So my SA - Low Speed and High Speed tables are my final SA values (after CTS compensations which at operating temp are 0)
Once I actually get it to run well open loop I will then look into giving closed loop tuning a try and implement PE.
Went for a short drive. The first bin was just a little bit better. I pulled over and reduced the whole SA Tables by 20% as well as idle SA. The issue itself was much better it seemed. I know it was lean which will be part of the surging I was feeling on the drive back when this was recorded.
Looking back at this recording I have a question for other EBL users. I know the calc for final sa when accounting for the cts and iat compensation bias. But how is initial sa taken into account? Is it added in addition to the main tables and then reported to the WUD? It appears so as even on this log I am still showing over 30* SA but the tables never go over 30 now?
Tomorrow I am going to try a tune with 8* taken out of the tables (my initial timing is set at 8*). I am going to run a learn off the datalog as well and smooth it out some before running it. Will see what happens.
Looking back at this recording I have a question for other EBL users. I know the calc for final sa when accounting for the cts and iat compensation bias. It appears so as even on this log I am still showing over 30* SA but the tables never go over 30 now?
There are quite a few SA modifiers. Need to go through the BIN at particular times in the log to see what is affecting the final SA.
But how is initial sa taken into account? Is it added in addition to the main tables and then reported to the WUD?
Ignore the initial SA. As long as the physical base and the calibration parameter match, it doesn't affect the final SA. The ECM subtracts the Initial SA out, with the physical position of the distributor adding it back in.
I have a false knock from something. Its been there for years.
This should be corrected. It is a constant knock & retard when under light cruise conditions. And can very easily be contributing to the stuttering.
There are quite a few SA modifiers. Need to go through the BIN at particular times in the log to see what is affecting the final SA.
Ignore the initial SA. As long as the physical base and the calibration parameter match, it doesn't affect the final SA. The ECM subtracts the Initial SA out, with the physical position of the distributor adding it back in.
This should be corrected. It is a constant knock & retard when under light cruise conditions. And can very easily be contributing to the stuttering.
RBob.
Yes, with the other spark advance modifiers at temp there should be 0 modification to the final spark. 9.84 bias with 9.84 in the tables around operating temp.
Good to know on the initial. I had actually just before lunch read another post giving some detail on that.
I plan on looking into the false knock situation. I need to make sure I am running the EST module that is more forgiving and then possibly add a 90* fitting to the knock sensor. I'm pretty sure it is from my passenger side header being millimeters from the frame and probably hitting when running/driving.
Took it for a short drive at lunch and it ran MUCH better. Still had some jerkiness here and there in a few scenarios like letting clutch out while rolling into throttle for making turns. I will try a few changes to the spark in those areas and see what happens. Fueling was much better this time around as well compared to last night. Granted it never got to temp though. Will let it warm up fully tonight on a drive.
Something in my head keeps saying that these spark advance values are really low. I know how the line goes "give the engine what it wants". I guess I am overthinking things? Maybe I will look into verifying my TDC and my 0* timing mark just to confirm my base timing is indeed 8*.
Ran another test drive last night. This one a bit longer and was able to run a VE Learn. Was on the rich side of my commanded so it was pulling a decent amount of full for the most part. But all in all it was extremely drivable and I was able to "cruise" in town at 30-45 and also down the highway at 70.
I am still getting a LOT of knock counts and timing being pulled because of it. I really can't imagine how it could be true knock at such low spark advance? Any input on that would be great. Maybe my base timing is off or my timing tabs aren't true TDC? It starts up quickly and goes right to idle so I can't imagine my base timing being too far off.
Anyways here is the datalog. 2018-09-25_CUSTOMSA_SMVE00009.zip Next evening I am free I might throw a timing light on it so I can verify it.
There are 2 sets of timing tabs/dampers for sbc's. Had a mixed set on an engine I picked up. They can throw your timing off by quite a bit. Dont remember offhand how far off it goes, but it was something like 20deg.
Thanks for the links. I've ordered a piston stop to use in verifying my TDC on my timing marks. Hopefully all is well but if not I will correct it and move forward from there.
Drove it to work today and noticed a bit of surging just after startup when taking off from stops. Didn't have the tablet hooked up but assumed it was my SA - Choke and CTS compensations as they haven't been touched. Reduced them some over lunch and will test again next cold start. Temperatures were the coldest this morning since spring being in the upper 40s I think when I woke up.
I have not done that check. At operating temp and yesterday when it was much warmer outside on first startup when leaving the house it was much warmer. So I am fairly confident what I experienced today when it was cold is something with the startup/warm-up parameters. If I experience any thing that affects how it runs consistently regardless of temps then I will do a test. Vacuum readings are right where they should be so I think I am clear there.
Figure I will update this a bit more as the saga continues.
Last night I went to confirm my TDC using a piston stop I had ordered...well apparently I ordered the wrong one and it wasn't the right one for standard spark plug threads.
I went ahead and marked the balancer to put the timing light on it. Unplugged the EST Connector and started it up. Checked where the timing was and it was WAY back (counterclockwise) from my timing tab. So I let it warm up completely and loosened the distributor up to set it to 8*. As I turned brought it closer to 8* it idled down and the IAC came in to bring it back to commanded idle. Once it was set at 8* the IAC was fully open. So I left it running and went inside to grab my tablet so I could reset my throttle screw for around 20-30 steps. Came out and got it all hooked up and running and started adjusting the idle up some. At around 1400rpms the IAC had stopped coming down for some reason around 130 steps. I walked around and confirmed that. Checked my WB which was around 15.0-15.5. Then walked back to the front and noticed my headers were starting to turn a little cherry red. Shut it down to cool off for a second and plugged the EST back in. Set my idle SA to 20* and started it back up and it went right to idle and needed minor adjustment of the throttle screw from there.
So whats up with the headers starting to glow? Could that have just been from it spinning at 1300-1400rpm and being slightly lean along with the timing being set how it was?
I plan to take and order the correct piston stop to actually confirm TDC. I still don't fully trust my timing tab relationship with the balancer mark.
Regardless, I went back and updated the Spark Table I was running by adding 8* across the board and went for a test ride. It ran good. I'm still having issues with IAT/CTS Blending I believe. Once the motor is warm and I drive in town enough or shut down and restart after a few minutes my AFR goes to the lean side at idle and low rpm/low map areas (low gram/sec areas) My IAT raises to 140* at the worst and at highway speeds drops to 115*. This is with 4" intake to the driverside fender hole without being sealed from the engine side. That is next on the list of things to do besides checking TDC.
Last night I used one of those laser temperature readers on the headers because I had borrowed it for another task. I noted that there was a large variance between a couple of the tubes. I measured about 1-2" off the flange on all of them. Some were in the 600-700*F range but a couple were around 400*F. These are Dyno Don Headers bought many years back. Not sure if they have always been ceramic coated or if thats a new thing he started doing post me purchasing. I know my underhood temps have always been pretty high so I don't think they are coated...
To note: This drive was with edited VE Tables and it was no longer on the lean side.
I am curious what the variation is from? That was after a longish drive through town with stop and go. Fully to temp and with probably 3mins idling time in the driveway.
The correct piston stop will be here by Saturday so I will be confirming my TDC over the weekend. The car honestly feels very doggy after resetting the timing. Around 2000 rpm and up with easy throttle just accelerating through the gears it feels like I am dragging the brakes almost.
I'm convinced something isn't adding up with my timing marks and where it is set at now is actually somewhere AFTER TDC...this weekends TDC will be very beneficial I hope in solving this once and for all. I will also be pulling atleast the distributor cap to inspect and confirm it was dropped in pointing at #1 and isn't off some.
Last edited by dabomb6608; 10-04-2018 at 11:09 AM.
Had a couple of cylinders getting weak spark from plugwire/header contact and saw something similar. May want to doublecheck all of your plugs/wires, check in the dark see if you have any arcing.
Well I confirmed my TDC this weekend. My timing marks are all correct (maybe 1* at most off). I also confirmed the distributor was set correctly as well. When doing so I noticed the cap and rotor were a bit corroded so bought replacements. I also noted that the magnetic pickup/reluctor was pretty rusty. I might end up getting a whole new distributor just to be sure.
From there I wanted to set base timing at 10* BTDC and when sitting watching the light on the markers with it idling I noticed every 5-10 seconds or so it would kind of blip to like 2-6 BTDC. This is with the ESC Connector unplugged. Not really sure what would cause that, maybe a failing ICM?
I guess at this point I need to assess the potential false knock count situation. I am almost positive my passenger side header is coming into contact with the frame rail, and believe that to be the culprit.
Spring is here and I am going to begin slowly working on the Trans Am again as I get some spare time. I work full time and run a Jetski/Boat repair shop on the side. As you can probably imagine this is my busy season. Currently backlogged with 2 boats and 3ish skis on wait with 4 skis already at the house. So please bear with me on delays between getting work or testing done.
Anyways, I have reread through this thread to refresh my memory. We left off with me needing to figure out my knock situation. I also had issues with my ECM no longer commanding the fuel pump prime at key on. ECM is on its way to BobR for repairs. In our emails I asked him about my knock issues and he informed me that my "ANAJ" Electronic Spark Control module was from a LO3 equipped car. I have ordered up a "BLH" ESC module that he recommended as being the preferred module. Once I get that and the ECM back I will do some testing to verify my knock sensor is within spec and go from there.
I am still considering replacing my injectors due to me having zero confirmed data to go off of with my current Deka Siemens 36lbs injectors. BobR recommended the "red" 30lbs Bosch D3 Injectors. I also have taken note of his recommendation early in this thread about my fuel line between the rails and hard lines. I need to do some searching to find a proper replacement that still looks good visually.
I want to get the knock issue figured out before moving forward with a injector swap as I know I was getting a almost constant spark reduction due to knock counts. That was definitely not helping my ability to tune efficiently.
I received the ECM back from rBob a few weeks back and have been driving the car a little bit. I also swapped out to the preferred "BLH" Electronic Spark Controller. My knock counts seem to have been reduced some. But I am still getting a very consistent spark pull due to knock at 1800-2300 RPM during normal driving and acceleration from stop lights. I am fairly convinced this is a false knock situation. I hear no obvious knock (the car is very loud so not the best way to confirm). I have new plugs ready to go in and will inspect the current plugs at that time for any signs of knock.
I am showing a commanded 18* SA at almost every spot that I am seeing it pulled from knock. That seems incredibly low for my setup to be seeing any kind of knock during light/moderate acceleration. I also am running non-ethanol 92 octane fuel to help reduce any potential true knock. My fueling isn't perfect by any means but is good at the areas of knock counts.
Here is a log from yesterday evening as well as my current bin file. A note on my IAT readings. I am currently working on sealing my CAI so that it draws from the drivers fender cutout. I have the aluminum to create the piece but my angle grinder quit on me. Would like to have that finished soon though to hopefully see those numbers drop some.
Those knock sensors have been known to pick up all kinds of strangeness. Exhaust leaks, or exhaust pipe hitting something and logging a knock.
It doesn't help that there isn't a knock sensor "designed" for the 400 SBC motors. I'm running a 350 knock sensor. Between the exhaust that I know has a few small leaks and the passenger side flange being very close to the firewall I don't doubt I am picking up false knock. I might try adding some teflon tape around the threads to quiet it down some.
Re: EBL Tuning a 406 with XFI280 & FIRST Intake - Mechanical Issues or Tune?
Not familiar w/ the tables in that ecm, but on newer ecm's there's a sensitivity table for the knock sensors that can be adjusted. May be something to consider.
Re: EBL Tuning a 406 with XFI280 & FIRST Intake - Mechanical Issues or Tune?
Originally Posted by JoshHefnerX
Not familiar w/ the tables in that ecm, but on newer ecm's there's a sensitivity table for the knock sensors that can be adjusted. May be something to consider.
No options on this for that. Can only desensitize the sensor itself via physical methods.
Was looking at my logs from last night paying attention to my AFRs during shifts. I think I got my deceleration enleanment to the point that it is swinging things slightly rich. I did this for two reasons. I was seeing a lean spike on throttle lifts and shifts. Now I am seeing a initial rich swing followed by a smaller lean spike on shifts. So I believe I removed some excessive leanness caused by the DE and can now make some changes to AE.
On several shifts during normal acceleration from full stops I noticed I wasn't even activating AE. Check out my screenshots.
Both shifts shown above don't even activate AE. So let me know if what I have changed is heading in the right direction.
At this point I didn't want to make any PW changes. No point changing the volume of AE when its not even getting commanded correctly. What I did adjust is my AE - <TPS% Double MAP Threshold from the default 10% to 5%. My thought process here is that the FIRST Intakes' large 4" monoblade throttle body it really doesn't take much throttle to get moving. So with normal driving I'm never really getting much over 20% throttle. In the entire 8min log above I never touched 20% throttle.
All of that being said, with such little movement of TPS required for regular driving I believe that setting was too high. I wasn't meeting the doubled value requirement of MAP from what I could tell. I will see how it performs next time I take it for a drive and go from there.
Re: EBL Tuning a 406 with XFI280 & FIRST Intake - Mechanical Issues or Tune?
In the log, delta TPS AE will be shown via the aPW column. The delta MAP AE will be shown via the aePW column. This is due to being a port injected engine. The TPS based AE is added via asynchronous injections. While MAP AE is added via the main synchronous injection.
You are also moving the throttle slowly, which will produce low delta TPS and MAP values. Note that a dump of the log will show more AE information, including the delta values.
Can work with the TPS filter table (lower value is more AE), and the TPS PW table (larger value is more AE).
Re: EBL Tuning a 406 with XFI280 & FIRST Intake - Mechanical Issues or Tune?
Originally Posted by Orr89RocZ
Could it be possible your low map tables are commanding to much fuel in ve? I see 28-30 kpa 2200-2400 rpm at 0% tps at 12’s afr! Thats way rich
Then with throttle load comes up 50-58 kpa 1700-1800 rpm goes lean. Maybe ve needs adjustment ?
same thing in second pic. 2700 rpm is low map 20’s kpa. As a shift happens rpms drop load increases, map goes to 50’s. Fuel leans out
also spark is 15-20 deg lower than it should be
The VE tables are tapered correctly to give more fuel at those 50-60 kpa range vs the lower ranges so I don't believe I am very far off on them. I am currently commanding at or just under 14 afr for the majority of cruise rpm/vac areas. I think the swing to 12s we are seeing is my DE adjustment. I went a bit heavy on removing DE affects. I could probably bring a bit of the DE back in to remove that initial rich swing on throttle lift when DE activates. But I want to correct the lean spot on initial throttle opening immediately following first.
My spark is currently low until I get the false knock situation handled. I agree it could be much higher, but I see a lot of SA pulled due to the knock its reading. See my previous post from yesterday on that.
Re: EBL Tuning a 406 with XFI280 & FIRST Intake - Mechanical Issues or Tune?
I will bump up my SA by around 5* or so and see how it takes it. I've reduced my knock max sa retard to be minimal at lower KPA levels to limit how much it reduces during normal driving.
I haven't removed decel enleanment completely. But reduced its factor to 0.10 from 0.44 default. I just bumped it up to 0.15 to see if that helps bring it towards target afr.
Steady state 1800-1600 range at around 30-40 KPA is in the mid to low 13s average. It agree it certainly could be tweaked some but I had it intentionally towards the rich side to curb some unwanted lean pop during engine brake and coasting with clutch still engaged. It helped but I haven't fine tuned it to see how lean I can go before it tries to start popping on me again. See below from my drive at lunch today.
For the drive back to work from my lunch break I had reduced my AE - <TPS% Double MAP Threshold down to 5.10 % TPS from 10.20 Default. I see what rBob is referring to I think about MAP AE not being accounted for in the analysis tab of the HUD. It shows once I dump the log in the excel sheet. See below.
I believe I need to get some additional MAP AE coming in due to the very limited throttle movement I am seeing not providing the extra TPS AE that would normally be added. To assist with more MAP AE being brought in I need to look at the AE - MAP Filter and raise or lower the filter? I see in the EBL Cal. file that a smaller value will be a greater lag. I would think more lag is needed? That way it creates higher delta MAP values? Am I correct in this thinking of how this all comes together and functions?
Re: EBL Tuning a 406 with XFI280 & FIRST Intake - Mechanical Issues or Tune?
I will be trying out the 3001 BIN timing tables. Was reading a post that rBob mentioned it to another user. I took that base table and subtracted about 7* across the board to get the idle area close to my current idle sa of 20*. Will see how it likes it and possibly bring some of the 7* I pulled back in. Here is how it looks with the 7* out from the 3001 Base Bin.
A note to keep in mind: I don't run any other compensations to my SA once the motor is at temp. I also am open loop so no PE is involved. So my SA- Main and Extended tables "should" be my final values. I understand my heads should allow for about 30* per Edelbrock. Until I get my false knock situation handled I would rather stay below that.
Re: EBL Tuning a 406 with XFI280 & FIRST Intake - Mechanical Issues or Tune?
Yesterdays drive went very well with the new SA tables. The torque seemed much more linear during normal acceleration. Some surging here and there at very light throttle cruise. But nothing drastic. I did a few hard throttle pulls as well. One 4th gear pull around the 5 min 13 second mark from ~3000 to 4000 rpm. With only a short WOT during that range. This throttle body is so large (perhaps oversized) that my 50% throttle actually puts my MAP in the 80KPA+ range. The next was a 2nd to 3rd gear WOT pull. About the 5 min 41 second mark. Knock counts were practically non-existent during the pulls which is a good sign. SA was around the 24* range. I've gone ahead and bumped my WOT SA 2* to try out next drive. AFR was decent. I added some fuel in the 3200-4000 range. But had to pull a tad from 4400 and up range. I am commanding 12.9 at WOT.
As for my AE situation...I was looking at some of the AE parameters in the 3001 BIN versus mine. I noticed that AE - Delta TPS% Threshold for AE was set to 0.78% in the 3001 BIN. Mine was at 1.96%. I have moved mine to the 0.78% as well now. I noticed in my logs that on normal shifts my delta TPS doesn't generally get above 1.5%. I will see how this affects things and adjust from there. I think it might introduce a bit to much AE until it gets fine tuned. I also will be bumping up my DE again. It is still bringing AFRs down a bit instead of holding them during the shift transitions from DE to AE.
On my WOT shifts I had a lean spike as well. Probably need to bump up the actual AE Pulse Widths for those areas.
Re: EBL Tuning a 406 with XFI280 & FIRST Intake - Mechanical Issues or Tune?
Some updates are in store.
I have been making some changes here and there and improving the tune more and more it seems. Right now I am running the SA table shown below (these are final values as compensations and PE are eliminated at operating temp). I also have lowered my AFR table some as this engine seems to like AFRs below 14 for reduced bucking/surging. I will be manually adjusting 1000rpm and below as this cam causes a false WB reading anyways. Will give the engine what it wants and shows on plug checks in that area regardless of what the WB says. I will also slowly lean out as much as I can while still staying away from bucking/surging.
In an effort to lower my IAT temps this weekend I decided to finally fab up my cold air intake box. Turned out well, unfortunately my laptop was dead with the charger at work so I couldn't do any datalogging to see how much of a difference it has made.
Re: EBL Tuning a 406 with XFI280 & FIRST Intake - Mechanical Issues or Tune?
Wanted to update this thread for future readers...
Never underestimate mechanical failures when chasing your tail on a tune. Finally getting back around to this old project and have found 6 partially wiped cam lobes. All intake side. 4 lifters had issues with the pushrod cups as well...
There is truly no telling how long these problems have been present. It's still crazy for me to think how it ran even given these issues...
I am now shopping for a new cam/lifters and correct springs. I can't wait to see what this setup is truly capable of!
09-24-2018, 09:07 AM
