Accel 7 tuning

[sweatnblood]

Does anybody know anyone that is a "GOOD" tuner with Accel 7, I'm here in San Diego and can't seem to find anybody who has this stuff down, it has a basic tune job now that ran me 850ish...but it's still not running as good as it should and I just don't want to go back if I'm not getting the results I expect PLEASE ANY HELP IN THE RIGHT DRIECTION

[RSX302]

I have a Gen 7 system that I've gotten pretty good at. I can try to assist if you would like. PM me with your issues, maybe we can chat over the phone this weekend.

[Jim Nilsen]

I feel your pain and can tell you that you will be a lot happier when you keep trying to do your own tuning. I have gotten help from members here and from other tuners and each one has info that will get you closer to a better tune.

Post up your questions and we will try to help.

There is a thread I started a while ago and I will try to bring it up so we can keep adding to the info so others can learn too!

[RSX302]

This has some good info in it...

DFI Training Doc

Tuning WOT is the easy part..Troubleshooting problems and tuning for everyday driving can be the challange.

[1bad68cat]

Does anybody know anyone that is a "GOOD" tuner with Accel 7, I'm here in San Diego and can't seem to find anybody who has this stuff down, it has a basic tune job now that ran me 850ish...but it's still not running as good as it should and I just don't want to go back if I'm not getting the results I expect PLEASE ANY HELP IN THE RIGHT DRIECTION

I'm in the exact same boat. Car was tuned, but I feel it should run better. Not all the features were used that I think would help with fuel economy. I.E fuel enrichment with certain percentage of throttle. Any help from members is greatly appreciated.

[RSX302]

What is your specific issue?

Dunno if this will help anyone, but my technique.

Tuning has many areas to look at and this will by far cover it all, but this is the basic starting point I use when tuning. (cruise mode)

Timing:
Make sure cell to cell steps are minimum. You will feel bobble if the step is too large, specially while part throttle cruising. I usually don't go more then 3 deg per cell in any direction if I can. You can get away with 5deg or a little more coming off of idle to 1500-2000rpm, but if that's where your gears are on the highway then you will need to keep it tighter. Depending on the engine, idle can be 15-25 deg and cruise full vacuum around 35-40deg. (fuel econo) Going up the "Vac scale into pressure if used, I decrease gradually (3-5deg max) to desired ending timing (24-26deg with 10-12 psig boost) again, engine set-up will determine WOT timing. When you run a 1 bar map, resolution will be much better for smaller changes. 3bar will be greater.

A/F Tables:
I run idle anywhere between 14 -14.5 depending on what the engine likes and full vac cruise at 14.5-15. (I ran 15.5 a/f with 38deg on my Ford R302 and got 30mpg w/75# inj...sweet)
Side to side (RPM) cells stay pretty close to the same , but as you run up the pressure cells I drop about .2 a/f each cell (.5 max) to desired WOT A/F (again, map dependant) Boost around 11.8 A/F or fatter to be safe. 12.5 A/F for N/A.

Fuel VE:
For me, a wide band O2 is a must for this section. For fuel trim it's much easier with the passenger making the changes. I also keep the closed loop adjustment on to allow time for you to make the change and not run the engine too lean. Set to +/- 20% in all correction cells.
Cruise around and only make adjustment to VE cells without tipping into the throttle as much as possible covering as many VE cells as possible at different rpm and loads. With the A/F table already set, you can adjust each VE cell based on the correction factor. (this makes self tuning easier) I target 0% +/- 5%. Once the cells are close and you find each time the throttle is tipped in and your A/F goes low or high, adjust the Acceleration Modifier (tip in fuel) up or down as needed. All section will get repeated for fine tuning. Many hours had here for nice drivability..
After everything is tuned nicely, and tune WOT with a couple of data logs, I reduce the correction adjustment down to 10% below 3000rpm and 0% above. This way if the O2 starts going bad, my engine doesn't go lean at WOT. I use a dash mount A/F to keep an eye on things.

[1bad68cat]

One of the issues I have is that it runs lean on the driver's side bank. I verified with my Dynojet wide band. Switched the sensor between both banks. Driver's side is a full point leaner. I checked for vacuum leaks and such but could not find any. Swapped fuel injectors also. The car does have an intermittent sputter at cruise.

[RSX302]

One of the issues I have is that it runs lean on the driver's side bank. I verified with my Dynojet wide band. Switched the sensor between both banks. Driver's side is a full point leaner. I checked for vacuum leaks and such but could not find any. Swapped fuel injectors also. The car does have an intermittent sputter at cruise.

If you have a lean cylinder(s) it will caugh up the intake.

What intake do you have?

Are you running Sequential or Bank to Bank?

[1bad68cat]

I have the intake from Accel that comes with the DFI kit. I have it running sequential. What do you mean by coughing up the intake? Is there something else I should be looking for? Just a run down of what I have: 68 Cougar w/ 302 SBF. Running World Products Jr heads. Have an off the shelf X-Treme energy cam from comp w/ beehive springs. TKO600 running to a 9" with 3.89 gears and detroit trutrac. One other thing I forgot to mention was that the sputtering only started doing this after the car sat for a year. Although, I did start it everyday. The car has always ran lean on the driver's bank even before the sputtering started. I've installed 3 MSD 6ALs (thinking it was it), 2 coils, and 2 reluctors. The sequential is run using a MSD billet distributor with all but one tooth removed from the reluctor wheel and a MSD crank trigger. I didn't use a dual sink because when I installed the distributor, it was a month old and didn't want to spend the money on a dual sync distributor. When I got the car back from the dyno shop it did make good power for what I had (345 hp/325tq to the wheels). But that's all WOT stuff. The car behaves properly at WOT. I think the car just needs to be tuned better across the RPM range.

[RSX302]

I have the intake from Accel that comes with the DFI kit. I have it running sequential. What do you mean by coughing up the intake? Is there something else I should be looking for? Just a run down of what I have: 68 Cougar w/ 302 SBF. Running World Products Jr heads. Have an off the shelf X-Treme energy cam from comp w/ beehive springs. TKO600 running to a 9" with 3.89 gears and detroit trutrac. One other thing I forgot to mention was that the sputtering only started doing this after the car sat for a year. Although, I did start it everyday. The car has always ran lean on the driver's bank even before the sputtering started. I've installed 3 MSD 6ALs (thinking it was it), 2 coils, and 2 reluctors. The sequential is run using a MSD billet distributor with all but one tooth removed from the reluctor wheel and a MSD crank trigger. I didn't use a dual sink because when I installed the distributor, it was a month old and didn't want to spend the money on a dual sync distributor. When I got the car back from the dyno shop it did make good power for what I had (345 hp/325tq to the wheels). But that's all WOT stuff. The car behaves properly at WOT. I think the car just needs to be tuned better across the RPM range.

I'm more worried about fixing the side to side A/F issue before working on the tune.

A lean condition will have a tendancy to caugh (spit) back up the intake. I believe it's caused by preignition firing before the intake valve fully closes. The leaner it gets the worse it gets. Sometimes it can be mild. Usually hear/feel during tip in if not enough fuel added to accel modifier.

3-6AL's? 2-Coils? Can't say I'm familiar with what you got going on with the ignition. Sounds like more then you need. Got pictures? You only need one 6AL feeding one coil to your MSD distributor.

"The sequential is run using a MSD billet distributor with all but one tooth removed from the reluctor wheel and a MSD crank trigger."

I can assume that the distributor is giving you the cam trigger for sequential. If I remember right, my Accel Dual Sync is the opposite way. All solid around and opens at TDC for cam trigger? I will verify this when I get home.

Easy way to check; put system to Bank to Bank. (removes the need for cam trigger) Engine will run a little fatter, but intresting to see if it clears up? More so evening out the banks A/F?

At WOT does the side to side A/F even out?

[RSX302]

Oh..sorry sweatnblood for taking from your original post..

[RSX302]

3-6AL's? 2-Coils? Can't say I'm familiar with what you got going on with the ignition. Sounds like more then you need. You only need one 6AL feeding one coil to your MSD distributor.

Goofy me..I guess I need to read your thread a little better...DOH!

[RSX302]

I can assume that the distributor is giving you the cam trigger for sequential. If I remember right, my Accel Dual Sync is the opposite way. All solid around and opens at TDC for cam trigger? I will verify this when I get home.

Verified; the Accel dual sync distributor has the cam sensor armature running through the hall effect sensor all the way around until it gets to #1 cyl where it is open. Don't know if this would be of any reason why you'd experience a side to side A/F difference. Again I think running in bank to bank mode would confirm that.

One thing I'd say is that you may not be lean on one side, but maybe too rich on the other making you think you're too lean.

Fatten the lean side up (VE fueling table) and drive it around. Check the plugs and see if there is a single cylinder rich or the whole bank. Also make sure the individual cylinder fueling adjustments are all the same.

Just throwing a bunch out there to see what sticks...It can be very difficult troubleshooting without being at the car. Sometimes it can be difficult at the car too..

My most difficult to date was diagnosing a cracked pin on the hall effect sensor on a Accel Dual Sync distributor. That was fun...but now I know

[1bad68cat]

Yeah, using the MSD as my cam signal. I've tried running in batch but no change. The AFR starts at 15.1/14.1 then fattens up to 13.8/12.8 by WOT. The whole bank runs lean. How do I go about fattening up the one bank? I tried accel's website, google searches and even searches here but could not find anything. As for the coughing up the intake part, I want to assume yes because of some carbon build up in the throttle body. However, the carbon buildup may also be from my PCV valve. But I'm not sure. Thanks for your help RX302. I apologize SweatnBlood for hijacking your thread.

[RSX302]

Yeah, using the MSD as my cam signal. I've tried running in batch but no change. The AFR starts at 15.1/14.1 then fattens up to 13.8/12.8 by WOT. The whole bank runs lean. How do I go about fattening up the one bank? I tried accel's website, google searches and even searches here but could not find anything. As for the coughing up the intake part, I want to assume yes because of some carbon build up in the throttle body. However, the carbon buildup may also be from my PCV valve. But I'm not sure. Thanks for your help RX302. I apologize SweatnBlood for hijacking your thread.

Is it carbon dry or is it more oily? I've had intake manifold leaks from under the manifold in the valley that creates an oily intake.

http://www.accel-dfi.com/pdf/gen7-instructions.html

You don't want to fatten up one side only. We need to find out why it's different first. Check in the CalMap program to see if the Cylinder #1 - #8 Fuel Coefficient are all the same. Should be al around .990 or 1.00.

To increase or decrease fueling for all, go to the VE fueling table. Shortcut= F2 Tab (Base Volumetric Efficiency section in instructions) There you will see many cells. Increasing and decreasing these numbers will change your A/F. If you are not familar with this, you will need to be careful and not change to drastically. If not comfortable with this, you may want to send your file to someone to look at it. I can try if you want to PM me.

[1bad68cat]

Is it carbon dry or is it more oily? I've had intake manifold leaks from under the manifold in the valley that creates an oily intake.

You don't want to fatten up one side only. We need to find out why it's different first. Check in the CalMap program to see if the Cylinder #1 - #8 Fuel Coefficient are all the same. Should be al around .990 or 1.00.

I believe it is dry carbon, but I will recheck when I return home this weekend. If it is dry carbon, then I assume that is what you are referring to about coughing back up the intake? As for the fuel coefficients they are all @.992. I did adjust them to see if it would help my problem, but there was no change so I returned them back. The only thing I wondered is if both banks are making the same power. When I had the block machined, I requested to have the decks squared. I also remember when checking piston to valve clearance for all 8 cylinder, they were the same.

Just throwing out some ideas going through my head. Can the timing required for each bank be different? If so, can the timing be controlled individually for each cylinder in the ACCEL computer? If the timing required is different for the banks, should I re-degree the cam for each cylinder to verify the valves are actuating at the correct time? How can I adjust fuel injector offset to match the cam timing events?

[RSX302]

I believe it is dry carbon, but I will recheck when I return home this weekend. If it is dry carbon, then I assume that is what you are referring to about coughing back up the intake? As for the fuel coefficients they are all @.992. I did adjust them to see if it would help my problem, but there was no change so I returned them back. The only thing I wondered is if both banks are making the same power. When I had the block machined, I requested to have the decks squared. I also remember when checking piston to valve clearance for all 8 cylinder, they were the same.

Just throwing out some ideas going through my head. Can the timing required for each bank be different? If so, can the timing be controlled individually for each cylinder in the ACCEL computer? If the timing required is different for the banks, should I re-degree the cam for each cylinder to verify the valves are actuating at the correct time? How can I adjust fuel injector offset to match the cam timing events?

"Can the timing required for each bank be different?" Not thru a distributor. You can set the fuel injector timing. (should be around 310) this is based on the cam profile. That will affect all injector firing not just a side.

Minor timing won't create that wide of an A/F split. Typically its either Air or Fuel, but I have seen distributor phasing be out which caused stumbling at around 2500rpm, but ran fine otherwise. It did cause irratic A/F readings. We drilled a hole in the cap at #1 to find the rotor was sparking 1/4" before it got to the plug. That was cool looking, but...
I've also found a complete bank lean due to a bad ECU.

I was looking at riching up the lean drivers side to see if that equated to all cylinders on the passenger side going equally richer. If only one cylinder goes rich, that will cause the A/F on that side to show richer. It will also make the car drive nicer and get rid of your lean stumble while you search for the problem. Well, that's assuming your stumbling is being caused by a lean condition and not something else. If one cylinder is causing it, you will pick it up reading the plugs.

[1bad68cat]

"Can the timing required for each bank be different?" Not thru a distributor. You can set the fuel injector timing. (should be around 310) this is based on the cam profile. That will affect all injector firing not just a side.

Minor timing won't create that wide of an A/F split. Typically its either Air or Fuel, but I have seen distributor phasing be out which caused stumbling at around 2500rpm, but ran fine otherwise. It did cause irratic A/F readings. We drilled a hole in the cap at #1 to find the rotor was sparking 1/4" before it got to the plug. That was cool looking, but...
I've also found a complete bank lean due to a bad ECU.

I was looking at riching up the lean drivers side to see if that equated to all cylinders on the passenger side going equally richer. If only one cylinder goes rich, that will cause the A/F on that side to show richer. It will also make the car drive nicer and get rid of your lean stumble while you search for the problem. Well, that's assuming your stumbling is being caused by a lean condition and not something else. If one cylinder is causing it, you will pick it up reading the plugs.

How do you change injector firing? I've tried looking for it in the past but could not find it.

As for the lean condition, it is the entire bank the way the plugs read. Is there a way to richen just the one side without affecting the other side?

[RSX302]

How do you change injector firing? I've tried looking for it in the past but could not find it.

As for the lean condition, it is the entire bank the way the plugs read. Is there a way to richen just the one side without affecting the other side?

I'm going off memory, but I think the Inj Firing timing is in the Fuel drop down in Steady State section. I don't think that is the issue, but good to check out what it is.

Even though you can't, you don't want to try and fatten up one side only. The system only has fine tuning with individual inj coefficient. This will only be used/needed if you have egt's on each cylinder.

I'm assuming the O2 is on the passeger side? Can you flip it over to the drivers side? Run it and what does it do? I would assume 14:1/13:1 A/F. Do you have O2 bungs in the same spot on each side (near/on the collectors)

[1bad68cat]

I'm assuming the O2 is on the passeger side? Can you flip it over to the drivers side? Run it and what does it do? I would assume 14:1/13:1 A/F. Do you have O2 bungs in the same spot on each side (near/on the collectors)

You are correct about the placement of the oxygen sensor. I did flip the )2 sensors, but still had the intermittent sputtering + more fuel consumption which confirmed to me...in my eyes... that the driver's side bank was running leaner. The dyno shop also had confirmed by putting exhaust analyzers in both pipes just downstream of the O2 sensors.