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AFR too high; how much more fuel pressure is needed?

KnappAttack said:
How are these PEFI tunes running around with 3" straight thru mufflers then? My bud has a 3" Sandale on his. Ulmer sets them up with 3" mufflers, or at least did. How does Hurricane and TD get by with all these big mufflers without going that lean?
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Whenever I call in to TD for a map on any sled, they ALWAYS ask the details of what is on it for a muffler.(as well as all other mods)
 

justinator said:
TD asks you what exhaust you are running but the tunes are not muffler specific. Same tune for 3" exhaust as 2.5". I asked them because I have the pefi muffler, td sq 2.5" and recently got a 3" viney fab. They recommend 48psi with key on with closed loop because that way the system is mostly pulling fuel rather than adding it and if the sensor or module fails you are safer if you happen to be running some wacky hardware. If you dont have adjustable regulator you are all still fine.The regulator was required for header before they had header specific tunes. Now that they have have header specific tunes you are only required to have big fuel pump for all header tunes.
Now regarding the pefi muffler which I have many miles of use on......It works good overall and yes its more restrictive then some of the straigh through mufflers but there isnt really a big seat of the pants difference. It didnt work as well as the td sq 2.5" muffler on a hurricane tune but that tune had no closed loop and was towards the end of the year so warmer weather and the afrs were a little towards the rich side, probably would of been better with closed loop. No issues running it on the TD sled as thats where it spent 2500 miles of its life, little less power than a straight through yes but doesnt make sled lethargic by any means. Like mentioned earlier, I am the one who shared the dyno results of my buddies 9000rr with stage 3r precision on the dyno comparing the pefi muffler and dd tech 2. I learned today that the previous owner(who is the one who had it dynoed) had it dynoed at D&D. Now I am a bit of a skeptic when someone is running their competitors product vs theirs on their dyno. No doubt the tech 2 flows more but was it as drastic as dyno showed.......I dont know. guys around here fab up straight pipes for lake race days with no issues. Ive swapped between 2.5 and 3" mufflers and viewed my data logs and fuel multiplier is doing very little different to keep afrs in check. Even without closed loop I would be safe to run. I dont understand how a tune can be so different that a muffler swap sends it right over into engine destruction territory. The tech 2 straight through muffler may flow more than some of the 3" baffled muffler but it certainly doesnt flow more than a 3" straight through muffler. All I can say with 100% certainty is that if it were me, after spending all that money on a rebuild, and now seeing this I would buy a gap map sensor and a tune from one of the 2 tuners utilizing gap and enjoy my much safer tuning and have the ability to play with hardware a little bit without having a meltdown and have fully functioning knock protection. You already have larger pump and exhaust so no new hardware required. From the past year or so I have concluded their is some sketchy schit going on in quebec.
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Not for all header tunes that TD makes. The TD MaxSpool 16 SM header tune does not require larger fuel pump, but any of their tunes that produce over 290 hp would need larger volume fuel pump. Part of my reason to stay with the 285hp MS 17 w/2.5” SQ muffler. Bov and 3 bar sensor needed! Haven’t tried it yet...

In fact, the first version of their MS 16 sm header tune was a 2 bar sensor tune! Same tune for header and non header back then. Then came the separate 2 bar tunes for header and non header Sm 16. And then finally the 3 bar MS 16 tunes.

My point: one needs to know the exact requirements of a tune if buying a used Winder with a tune in it because of how fast the tunes have evolved!
 
Motorhead said:
Not for all header tunes that TD makes. The TD MaxSpool 16 SM header tune does not require larger fuel pump, but any of their tunes that produce over 290 hp would need larger volume fuel pump. Part of my reason to stay with the 285hp MS 17 w/2.5” SQ muffler. Bov and 3 bar sensor needed! Haven’t tried it yet...

In fact, the first version of their MS 16 sm header tune was a 2 bar sensor tune! Same tune for header and non header back then. Then came the separate 2 bar tunes for header and non header Sm 16. And then finally the 3 bar MS 16 tunes.

My point: one needs to know the exact requirements of a tune if buying a used Winder with a tune in it because of how fast the tunes have evolved!
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Speaking with Mike last winter they wanted all header tunes to have big pump but none the less, yes you are correct…….The reason they ask alot of questions when you get a tune is to make sure you have correct map sensor, bov if required ,proper exhaust , fuel pump etc . They dont have 10 versions of the same tune for each exhaust on the market……if you buy a power muffler tune you get a power muffler tune and can run a 2.5 or switch to a 3 and be good to go. They are trying to prevent people from having issues and calling back because sled wont run right because customer didnt know the requirements. In the case of pefi, if their tunes only work with their specific muffler it ahould be sold as a kit and only a kit because there is alot of guys out there riding around with exhausts of their choosing. They wont sell you stage 4 without buying their header and they wont sell the header seperate because its matched to the tune. Why is it ok for stage 3 to not include their muffler? At the very least they should include a potato to plug your exhaust so afrs stay safe.
 
74Nitro said:
Whenever I call in to TD for a map on any sled, they ALWAYS ask the details of what is on it for a muffler.(as well as all other mods)
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That's why I got the hurricane trail muffler for my Hurricane Tunes. IMO, each muffler needs to be tuned for each mapping...
 
justinator said:
Speaking with Mike last winter they wanted all header tunes to have big pump but none the less, yes you are correct…….The reason they ask alot of questions when you get a tune is to make sure you have correct map sensor, bov if required ,proper exhaust , fuel pump etc . They dont have 10 versions of the same tune for each exhaust on the market……if you buy a power muffler tune you get a power muffler tune and can run a 2.5 or switch to a 3 and be good to go. They are trying to prevent people from having issues and calling back because sled wont run right because customer didnt know the requirements. In the case of pefi, if their tunes only work with their specific muffler it ahould be sold as a kit and only a kit because there is alot of guys out there riding around with exhausts of their choosing. They wont sell you stage 4 without buying their header and they wont sell the header seperate because its matched to the tune. Why is it ok for stage 3 to not include their muffler? At the very least they should include a potato to plug your exhaust so afrs stay safe.
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Agree, I'm very concerned for my bud running the PEFI bundle with his 3" Sandale on it after seeing this. He had no A/F gauge on it nor any logging which I know to be invaluable for me. Pissing in the wind not knowing the A/F ratio especially seeing all these PEFI tuned engines go down last season...

Some people just buy stuff and have no idea on the repercussions of how it all goes together and what to expect. I warned my bud about that big muffler on there last season and his answer was the PEFI dealer is selling it and putting it on them, soooo.... Guess he's been warned. The good thing is he does jack the race fuel in all the time, so that's probably saving the engine, maybe he knows more than I think he does.
 
justinator said:
Speaking with Mike last winter they wanted all header tunes to have big pump but none the less, yes you are correct…….The reason they ask alot of questions when you get a tune is to make sure you have correct map sensor, bov if required ,proper exhaust , fuel pump etc . They dont have 10 versions of the same tune for each exhaust on the market……if you buy a power muffler tune you get a power muffler tune and can run a 2.5 or switch to a 3 and be good to go. They are trying to prevent people from having issues and calling back because sled wont run right because customer didnt know the requirements. In the case of pefi, if their tunes only work with their specific muffler it ahould be sold as a kit and only a kit because there is alot of guys out there riding around with exhausts of their choosing. They wont sell you stage 4 without buying their header and they wont sell the header seperate because its matched to the tune. Why is it ok for stage 3 to not include their muffler? At the very least they should include a potato to plug your exhaust so afrs stay safe.
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Ha Ha, I love that potato plug thing!
This is another great post for those who are thinking tunes! I have stayed mild in comparison to many on here that have the correct info and hardware with data logging, AFR’s, and other safety monitors that keep motors from burning down when looking for more then (mild) tunes!

Just really great info from all of you guys that have been, or are there now in regard to more safe power and what it takes to keep it safe motor wise!

I rely completely on my tuner for all tunes that I have tried, and have to say that the info that I have gained about all theses tunes have mostly come from TY prior to making a Decision and talking it over with the people at TD. No AFR gauge but that deto knock protection has been my only thing to watch for during my race/rides, besides rpm’s and speed and temps!!



My simplistic tunes of so far have kept all safe so far!

Thanks for all of this high tech info on tunes, it is very insightful to say the least!
 
sideshowBob said:
I just did a 100 mile ride a few days ago. I left the AFR display up on my display the whole ride. On the 240 PM tune it would momentarily read up to 14:1 at part throttle slower cruising but mostly between 12:1 and 13:1 and would immediately go to high 11s or low 12s with any aggressive throttle inputs. I don't typically leave my Gap flasher connected so I didn't do any data logging.
This was on the 240 tune with closed loop.
My mileage was good as well.
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I do just the opposite, my flasher is on the sled all the time along with my iPhone in the charger in front of me, live data is always right there at a glance and I log every second it's running. I can go back and look at the entire ride every time to dial everything right in for the day.
 
KnappAttack said:
I do just the opposite, my flasher is on the sled all the time along with my iPhone in the charger in front of me, live data is always right there at a glance and I log every second it's running. I can go back and look at the entire ride every time to dial everything right in for the day.
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Next ride I will try data logging the whole time...I need to get used to using it. Is there no end to its memory on long rides?
 
sideshowBob said:
I just did a 100 mile ride a few days ago. I left the AFR display up on my display the whole ride. On the 240 PM tune it would momentarily read up to 14:1 at part throttle slower cruising but mostly between 12:1 and 13:1 and would immediately go to high 11s or low 12s with any aggressive throttle inputs. I don't typically leave my Gap flasher connected so I didn't do any data logging.
This was on the 240 tune with closed loop.
My mileage was good
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That about the same with 300 header
I recorded this data with a screen recording app
 
At one time pefi stated any 2.5" free flowing muffler for stage 3, stage 2 was 2.25" muffler, and they made sure you understood ONLY stock airbox, this was back in 2019 when speedwrks did mine, things change since then? Dont know.
 
sideshowBob said:
Next ride I will try data logging the whole time...I need to get used to using it. Is there no end to its memory on long rides?
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Not that I have found. I use it ALL the time as I have my phone charging and staying warm in my Qi charger and case right in front of me.
 
"and would immediately go to high 11s or low 12s with any aggressive throttle inputs"

Thinking this is what we want to see. Every time handle barred it would immediately go to 11.7 and stay at that number.. New 2022 with TD max17 . Couple second holds.. Small sample size with 220 miles on sled.
 
After playing around with my Motec now in the apex, I realize how blind I was running the PEFI tune in my sidewinder. You know my thoughts on them. If I am going to play with the Winder again it will have a PnP Motec on it. These flashes are just chances as so many things are different from sled to sled and even day to day.

@Turboflash I would keep cranking the PSI up, no harm unless it gets so high it wont idle but it sounds like you are a long ways off from that.
 
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