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I reconfigured my timing table for "reverse flex fuel", as I plan on running E85 all the time, not pump 93. I'm only going to switch to 93 for winter storage. Had a 2D table that added about 5 degrees over 50% ethanol, I switched that around to remove timing under 50%. I'm still in the tuning process and still learning how to tune, purchased Joe Simpson's tuning program and have a lot better understanding of how things work, but I still would like some feedback as to whether this table is a reasonable starting point or not. Combo is 5.3 with 10.5:1 compression, Summit Pro LS pistons and rods, AFR Enforcer heads. Holley 120 lb./hr injectors:
I reconfigured my timing table for "reverse flex fuel", as I plan on running E85 all the time, not pump 93. I'm only going to switch to 93 for winter storage. Had a 2D table that added about 5 degrees over 50% ethanol, I switched that around to remove timing under 50%. I'm still in the tuning process and still learning how to tune, purchased Joe Simpson's tuning program and have a lot better understanding of how things work, but I still would like some feedback as to whether this table is a reasonable starting point or not. Combo is 5.3 with 10.5:1 compression, Summit Pro LS pistons and rods, AFR Enforcer heads. Holley 120 lb./hr injectors:
A little off topic but I had a set of those Holley 120 injectors and before I sold them I had them cleaned and flow tested and they were actually closer to 135 lb/hr.
Anybody have input here? I've done a few street pulls with this table and so far so good, saw 20 PSI on one pull ( still tuning my CO2 boost control as well ). Seems like a good start, but I'd like people with more experience to chime in.
I reconfigured my timing table for "reverse flex fuel", as I plan on running E85 all the time, not pump 93. I'm only going to switch to 93 for winter storage. Had a 2D table that added about 5 degrees over 50% ethanol, I switched that around to remove timing under 50%. I'm still in the tuning process and still learning how to tune, purchased Joe Simpson's tuning program and have a lot better understanding of how things work, but I still would like some feedback as to whether this table is a reasonable starting point or not. Combo is 5.3 with 10.5:1 compression, Summit Pro LS pistons and rods, AFR Enforcer heads. Holley 120 lb./hr injectors:
I'd say you'd have to add more timing. That table is similar to what I'm running on pump 91 with meth. It'll work. Do a pull and check the plug strap
I wanted to be conservative at first, so I made sure not to give it too much. I plan on going to the track and throwing in some new plugs to see where I'm at. Just want to be sure my table isn't completely out to lunch.
This is with meth though, correct?
I'm down around 12 degrees at 14 lbs. on pump gas only.
Yes sir that's with the meth. My controller is progressive so I start the spray at 7 psi and I'm all in by 15/16 psi. I switched up to snow performance nozzles recently and only have the single 16 and not really seeing any cooling so I'm gonna put the 14 in there as well which should match the 2 AEM 1000cc nozzles
Unfortunately, pump gas with meth ends up being a different animal than E85. I'm sure I can probably add a bit of timing at lower boost, I just don't want to tear something up. I may have to rent a dyno for a couple of hours to make some changes.
Unfortunately, pump gas with meth ends up being a different animal than E85. I'm sure I can probably add a bit of timing at lower boost, I just don't want to tear something up. I may have to rent a dyno for a couple of hours to make some changes.
Are you buying your e85 by the barrel or at the pump?? If pump e85, do you have a test kit or are you using a flex fuel sensor with some custom tables to make adjustments for the different levels of alcohol??
I've seen wildly different results from the same station some as low as e50 which could be catastrophic
Looks really good, wont know for sure until you get on a dyno or at the dragstrip to see your trap speed. I would say it is within a couple degrees either direction of where it will want to be.
Good thing with e85 is there is a pretty large tuning window, very forgiving.
Are you buying your e85 by the barrel or at the pump?? If pump e85, do you have a test kit or are you using a flex fuel sensor with some custom tables to make adjustments for the different levels of alcohol??
I've seen wildly different results from the same station some as low as e50 which could be catastrophic
I buy mine at the pump, I have a station that is consistently over 65%, which from what I can tell works as well as full E85. I have a custom table to adjust for E85 percentage, as well as one to pull timing if the level drops below 53%.
Looks really good, wont know for sure until you get on a dyno or at the dragstrip to see your trap speed. I would say it is within a couple degrees either direction of where it will want to be.
Good thing with e85 is there is a pretty large tuning window, very forgiving.
It rips pretty violently at 18PSI, I can tell you that much. After installing my CO2 system, it spools quick as hell. I'm seeing positive manifold pressure all the way down at 2K rpm, and I've hit nearly 18 lbs. in first gear, which it never did before. I was lucky to see 12 just running off the spring last year. I plan on going to Martin on Saturday, as I simply can't justify hitting redline in 4th gear on the street, it's going WAY too fast. I may also rent some dyno time at a place in Plainwell and get some more data.
Your commanded 15* could be 20*… or 10*… Or anywhere in between. So could the guy you are copying from. Unless you and the person you are copying from used a piston stop. Found TDC exactly. And know for certain your ECU is sync’d and follows that TDC dead nuts through the entire RPM band (not common) then it’s a gamble. Even then, different setups/combos will want different timing.
The only way to tune is to start at a known low and work your way up watching plugs. Personally, I’d find true TDC and make sure the ECU is sync’d correctly first. Generally, you want to run NA timing up to 4-5psi on e85. So 28-32* in most cases on mild 5.3. That will give you a healthy transition into boost aka best “spool time”.
5psi and up start low. Dial in fuel and boost first. I usually make runs in 5psi intervals up to 25 to start 10* at 25psi and I interpolate back to 4psi for a decent curve. Then I take a degree or two out around PK TQ. From there adjust the table as a whole form 5-25psi. Adding 1* until the heat mark on the plug strap is about half way down the strap and just into the first thread. (or until you stop gaining MPH at track, draggy, dyno gains stop, etc)
If you are into the bend or the 2nd thread on the plug you are too hot IMO. I tune with a 7 NGK and move to an 8 once I'm tuned in most cases.
Your map looks very conservative for E85, esp. down low. But without seeing the plugs and knowing you are sync'd perfectly, its impossible to be sure.
Your commanded 15* could be 20*… or 10*… Or anywhere in between. So could the guy you are copying from. Unless you and the person you are copying from used a piston stop. Found TDC exactly. And know for certain your ECU is sync’d and follows that TDC dead nuts through the entire RPM band (not common) then it’s a gamble. Even then, different setups/combos will want different timing.
The only way to tune is to start at a known low and work your way up watching plugs. Personally, I’d find true TDC and make sure the ECU is sync’d correctly first. Generally, you want to run NA timing up to 4-5psi on e85. So 28-32* in most cases on mild 5.3. That will give you a healthy transition into boost aka best “spool time”.
5psi and up start low. Dial in fuel and boost first. I usually make runs in 5psi intervals up to 25 to start 10* at 25psi and I interpolate back to 4psi for a decent curve. Then I take a degree or two out around PK TQ. From there adjust the table as a whole form 5-25psi. Adding 1* until the heat mark on the plug strap is about half way down the strap and just into the first thread. (or until you stop gaining MPH at track, draggy, dyno gains stop, etc)
If you are into the bend or the 2nd thread on the plug you are too hot IMO. I tune with a 7 NGK and move to an 8 once I'm tuned in most cases.
Your map looks very conservative for E85, esp. down low. But without seeing the plugs and knowing you are sync'd perfectly, its impossible to be sure.
Do you have a part number for those heat range 8 plugs?
I'm running BR7EF's currently and also think this is good idea especially when running methanol injection.
Do you have a part number for those heat range 8 plugs?
I'm running BR7EF's currently and also think this is good idea especially when running methanol injection.
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How's this timing table look? 
