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^^^^This X2^^^^ you will generally see an island form in the mid-range area of a properly developed VE table. Peak torque always occurs at the highest cylinder pressure which also happens to be the most likely area to experience detonation. This is why I have posted many times that RPM is your friend and logging an engine is more likely to cause major damage due to this peak VE area. If you are trying to keep the heads on it I would ease up on the timing and try to get thru this area of the power curve as quickly as possible. Hope this helps.
 

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My situation is a little different than a lot. My car is light. It's track only. Yes you can have combinations where using peak torque can make a faster combination. But for turbo cars, my opinion is that there is no reason to have the converter load the engine during the run at or near peak torque for any time. That area is DANGER IMO. If it is track only and reasonably light for the hp you are making, use the HP and rpm. Your bearings and head gaskets will thank you.
 

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Discussion Starter #5
Thanks a lot! Looking at the VE Table there is a fat spot between 4400-4900.. Should I pull around 2 degrees? What else would you suggest?
 

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Discussion Starter #7
What's the preferred way to map timing? Are you guys all in say around like 2500, or do you guys ramp it up gradually with max timing at the redline??
 

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Depends what you are doing. Dyno can help determine what timing should be as max torque and power produced will show up when timing is correct. But depending how you want the power curve to look like, for traction purposes, you may choose to ramp it in slowly to create the curve you want
 

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I have posted on this forum several times how to create a safe/consistent timing map. Once this is accomplished you can start optimizing it for your needs. Use the search engine and I'm sure you will find multiple posts.
 

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I have posted on this forum several times how to create a safe/consistent timing map. Once this is accomplished you can start optimizing it for your needs. Use the search engine and I'm sure you will find multiple posts.
 

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Go find the post and the logic and math I use to generate the timing map. There is no one number, generalized values etc. That will end up with disappointment and a pile of broken parts. If you really want to learn, do your homework and actually learn something along the way. The info is here for the taking. I honestly don't want to go thru the whole process again. A lot of people have told me it was the best info and concept on boost timing maps they have seen.
 
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Go find the post and the logic and math I use to generate the timing map. There is no one number, generalized values etc. That will end up with disappointment and a pile of broken parts. If you really want to learn, do your homework and actually learn something along the way. The info is here for the taking. I honestly don't want to go thru the whole process again. A lot of people have told me it was the best info and concept on boost timing maps they have seen.
If you have some knowledge about what the heads, CR and fuel type would run for timing N/A there is a better way than big chunky adjustments that generally don't drive as good or perform as well at the track. Generally speaking a stock valve angle SBF with decent compression and good fuel like E85 that is ~105 octane 30* is a reasonable place to start. My race formula works the same way but is more aggressive and only pulls 0.5*/LB of boost after 10psi and up. RPM is your friend, don't lug the engine and definitely don't run a lot of boost around peak torque. Peak torque always happens at the highest cylinder pressure which is also where it's most likely to detonate. This method allows you to build a safe, consistent timing table that you can still tweak once it's working good and you can read the plugs etc.
That being said let's say 30* is our base timing so it's not a turd down low or hard to get up on the converter. We don't pull any timing until 5psi(super safe) then pull 1* for every 1# of boost. So at 10psi - 5== 5psi net boost.
5×1==5* timing to pull
30 - 5 == 25* @ 10psi

15psi - 5 == 10psi net boost.
10psi × 1 == 10* to pull
30* - 10* == 20* @ 15psi

20psi - 5 == 15psi net boost.
15 × 1psi/lb == 15* to pull
30* - 15* == 15* @ 20psi

25psi - 5 == 20psi net boost.
20 × 1psi/lb == 20* to pull
30* - 20* == 10* @ 25psi

You can do this in 1lb, 2lb, 5lb etc increments for whatever resolution you have in the timing table. You can also spot check your cells to make sure there following the curve and you don't have highs or lows that can effect performance or hurt parts. On race fuel I'm not afraid to run timing even higher than base if it needs it to spool or get up on the converter and still not pull any until 10psi. I generally only pull 0.5* per/lb of net boost. If you start off with a valid max timing value I have never seen it ever hurt parts. If I have info from where someone used a shitty map that hurt the engine and run the numbers my map would have never hurt the engine. This takes a little base knowledge but it really does work well and allows you to build a safe base map to start testing and tweak it in from there. Hope this helps.
 

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Thanks for posting it. There are also some older examples I have posted but the logic and math are the same but with slightly different examples. The most important thing to know is what the engine/head/chamber design uses for safe peak timing values in naturally asparated form. Hope this helps.
 

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Discussion Starter #15
I have posted on this forum several times how to create a safe/consistent timing map. Once this is accomplished you can start optimizing it for your needs. Use the search engine and I'm sure you will find multiple posts.
YES, I've seen and reviewed that thread!
I just need to get to a track and read plugs.. However, my kit in tight as fuck, and realistically will only let me change either plug 1 or 5 on the fly as everything is just to crowded and buried by the downtubes...




I modified my timing map.. I'm open to any criticisms.. The motor is 9.6:1 on Shell V-Power NiTRO+ Premium..


 

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Discussion Starter #17
It's been said that TFS 11R Heads make most power around 30 degrees.
Just trying to not blow it up!
It's a lot of work to tear things down with this setup.. I don't wanna do that! LOL
 

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I have seen this a lot and I'm by no means the Moderator but I feel like I need to say this for everyone's benefit. Don't get me wrong here, everyone wants to help and that's what makes this forum great. However, this is one of those times that if you don't know or don't have enough experience to give advice then you shouldn't. A SBF with modern aluminum heads does not need timing like a SBC or BBC. They are much more like a LS or a LS is like them. Either way 30* of timing is a lot and way plenty on pump fuel. Tempname runs a low boost, high rpm SBC in a BRACKET RACE APPLICATION on METHANOL in a ULTRALIGHT DRAGSTER that is nothing like most of us are trying to run at full tilt. Not everyone knows this because only about 3 people in the country run such a uncommon combo. The other thing I take issue with is if you have only tuned one car and it's a unicorn don't give tuning advice like an authority. If it's a comparable combo by all means share your experience but do so in such a way that they don't take it as the gospel and tear up a bunch of shit. Guys please be careful taking tuning advice from anyone online that doesn't know your combo entimently and you don't know their experience level. Go slow and read the plplugs. Happy Mothers Day you bunch of Motherfxxxxxs!!
 
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Tempname, I'm not trying to bust your balls. However my point is that if you have no experience with the combo being discussed and have only tuned one engine ever, I would not be offering unrelated advice that has no value to the person seeking help. I'm not being an asshole, I'm just being honest. There is a saying, "A drowning man will grab ahold of anything". It is quite possible a person struggling on their first EFI/boosted combo may take what they see here as the truth and the way then proceed to hurt a lot of parts at a minimum. I'm in no way saying you would intentionally misguide anyone but most people don't know what your combo/application is or it is the only turbo/EFI you have ever had and you have only run it for only one season if I'm not mistaken. If someone needs help on a low boost, high stall, high rpm, bracket raced SBC running Megasquirt EFI you are the authority on here for sure. It's a free country and you have every right to post whatever you want to. All I can ask on behalf of people needing help is to be clear about your level of experience and the combo you have experience with before offering advice. This is what I try to do myself. I don't know everything and don't claim to. If someone needs help tuning a blow-thru carb, I don't post. This goes for several different topics as far as I'm concerned.
 
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