How's this timing table look? 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: https://cimg3.ibsrv.net/gimg/ls1tech...7bd2509af6.png |
Originally Posted by LS1Formulation
(Post 20604961)
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: https://cimg3.ibsrv.net/gimg/ls1tech...7bd2509af6.png |
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. |
Originally Posted by LS1Formulation
(Post 20604961)
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: https://cimg3.ibsrv.net/gimg/ls1tech...7bd2509af6.png |
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. |
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Originally Posted by 91 Z28
(Post 20605315)
I'm down around 12 degrees at 14 lbs. on pump gas only. |
Originally Posted by The BallSS
(Post 20605322)
This is with meth though, correct? I'm down around 12 degrees at 14 lbs. on pump gas only. |
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. |
Originally Posted by LS1Formulation
(Post 20605335)
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. 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. |
Originally Posted by 91 Z28
(Post 20605340)
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 |
Originally Posted by wlink14
(Post 20605348)
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. |
Absolutely zero way to tell. 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. |
Originally Posted by Forcefed86
(Post 20605481)
I tune with a 7 NGK and move to an 8 once I'm tuned in most cases. |
Originally Posted by Forcefed86
(Post 20605481)
Absolutely zero way to tell. 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. I'm running BR7EF's currently and also think this is good idea especially when running methanol injection. |
Originally Posted by The BallSS
(Post 20605509)
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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