Melted a piston - unsure why.
Staging Lane
Joined: Jul 2016
Posts: 61
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Several SBC roots blown 12.5/1 comp 28psi 36° timing on methanol. Street blown engines I have done 32° to °34 pump 93 15-16psi. SBF roots 12 -14psi pump 93 32°. The engine you referenced must of had mix matched parts that didn't work together. IMHO
The 2014 F150 3.5 ecoboost (not direct injected) that I scanned myself went to 10.5- 10.8 (per the factory WB sensors) and 9* of advance at wot. The 4 cyl ecoboost cars I've messed with did about the same, except the mustang it went to 14* or so
9 Second Club
Joined: Nov 2003
Posts: 13,616
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From: Norn Iron
On a serious note 19° on my engine combo I feel is very safe and have seen others that are at 22° (same or similar engine) without any problems. In the coming weeks when I get time I'm gonna add a few ° check plugs and if all is good n happy, might even pull some fuel out a lil at a time to determine when she is right on the edge. This engine has been run many times WOT for more than a minute or two without even the temp rising a single degree.
Also, OEM ecoboost operates low 12s down to high 11s AFR when egts climb. Where this 10afr stuff comes from is beyond me. But that is totally irrelevant to this thread as both of my OEM turbo engines are direct injected and the burn rate of the atomized fuel is completely different.
one of my turbo engines operate at 29# of boost @ 29° of timing on pump gas for the last 4 years and not a single issue. Many hours at WOT on that one.
Also, OEM ecoboost operates low 12s down to high 11s AFR when egts climb. Where this 10afr stuff comes from is beyond me. But that is totally irrelevant to this thread as both of my OEM turbo engines are direct injected and the burn rate of the atomized fuel is completely different.
one of my turbo engines operate at 29# of boost @ 29° of timing on pump gas for the last 4 years and not a single issue. Many hours at WOT on that one.
It was a factory roots motor with headers and a pulley....but keep making completely irrelevant posts referencing methanol and direct injection motors....
Staging Lane
Joined: Jul 2016
Posts: 61
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Aint no roots sbc set up correctly gonna want jus 12° timing. If it was knocking then it was from too hot of cylinders from lack of timing. The diffence in power of a blown sbc with 6° more of timing can be worth upwards of a 100hp at wot. That and those using turbos is free hp if you know how to harness it
Aint no roots sbc set up correctly gonna want jus 12° timing. If it was knocking then it was from too hot of cylinders from lack of timing. The diffence in power of a blown sbc with 6° more of timing can be worth upwards of a 100hp at wot. That and those using turbos is free hp if you know how to harness it
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Verdad Gallardo Staging Lane
Joined: Jul 2016
Posts: 61
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Well being that I was referencing SBC and u made the comment about my post I jus thought u were talking about a sbc also. My bad. Have I ever blown up an engine, hell yes. A bunch of them in my early days, thats how I know what works and what dont. But most of the blown engines were with 700/800 hp of N02 on them. As for boosted engines not ever had much problems other than part failures like springs breaking, lifter failures wiping out a cams, had a holley carb come apart and sent boosters, vent tube and some other parts through the blower and into the engine. 30yrs of my experience is from inline 6cyl fords, sbc bbc and in the last few years the LS and Ecotec engines. In the 90s 1/4 racing I was the one that out ran the $25000 engines with a $7000 set up. Over and over again. Mid nines in those days with a 3700 lb daily driver was pretty damn fast. Drive to the track and drive home an hour each way. 2 to 3 times a month. These LS engines with an ECM is easy as hell compared to doing it the manual way of years past. But once you learn to tune, its all relevant, the one you just did is the same as the one your doing now jus a different engine trying to find what it likes. Never said any person on this site was a bad tuner jus that there might be additional power left unfound if ya dont know where the limit is. A good tuner will find that limit b4 he crosses it. Good luck with ur racing and enjoy it while ur here.
At least we can agree that there is more power left on the table with additional timing. I choose to sacrifice power for the sake of reliability. Where we differ is that you think running lesser timing than MBT is dangerous and I don't, that's all.
Staging Lane
Joined: Jul 2016
Posts: 61
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agreed with a little twist, I feel that low timing when combined with a rich mixture leaves unburnt fuel that can accumulate and that can and will cause problems. Contamination of the oil will also result. Now I'm no guru or high paid tuner, jus an ole motor head that still loves HP only trying to help not discourage.
That's fair. And my twist is that if its tuned for MBT timing, you leave no margin for a bad tank of gas or high IAT/heat soak. Also less margin should fuel pressure drop for whatever reason.
Staging Lane
Joined: Jul 2016
Posts: 61
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High IATs bad fuel, thats why we have an ecu/ecm to control what we can't. Ecu programed to pull timing if over the safe temp and if knock is detected to pull timing until knock is gone. That is jus too easy to write into the tune to protect the engine. Now do that without an ecu while still trying to stay at the top of ur game and making consistant back to back passes from early morning mid day to late afternoon while keeping the car hooked up. Back to the fuel, I can say aside from a sitting tank of gas, Ive never ran into a bad tank of fuel from the pump or race gas. Ethanol in the new fuels helps tremendously with a cushion as u call it. Now pushing a relatively stock engine past the limits for more power than it's design, well **** happens and parts will fail in time. I have seen time and time again where $30,000, $50,000 engines and more self destruct with very little run time. Was it part failure or tune, never seeing the build sheet or tear down, prob the result of the tune combined with the applied load. Lug a high hp engine and she's likely to rattle apart.
TECH Addict
Joined: Dec 2004
Posts: 2,177
Likes: 627
From: Florida
just keep adding timing a degree or two at a time til you crank a ring land, then back it off a little.
on a more serious note, i like 11.8 afrs past 10psi and 14* at 14psi ala sloppy has been my go-to timing
This forum is littered with examples of over-timing both in this section and in the N2O section. And now we're comparing SBE to $30-$50k engines....I'm sure they're all real street cars on regular gas too. Like I said, there's more than 1 way to skin a cat.....but until my stuff blows up I'm pretty happy with my method.
Staging Lane
Joined: Jul 2016
Posts: 61
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This forum is littered with examples of over-timing both in this section and in the N2O section. And now we're comparing SBE to $30-$50k engines....I'm sure they're all real street cars on regular gas too. Like I said, there's more than 1 way to skin a cat.....but until my stuff blows up I'm pretty happy with my method.
man o man, no where did I compare a OEM engine to a high dollar engine. I gave an example that no matter what engine you have if the tune is off and you subject that engine to too much load, it will not live. I don't studder nor do I type in tongues. Maybe the post should be read again you obviously missed everything.
TECH Addict
Joined: Dec 2004
Posts: 2,177
Likes: 627
From: Florida
Have you ever gotten a tank of bad gas? the only time ive seen the indicator of bad fuel is once in my evo. the evo will flash the CEL light when it sees more than like 5 knock counts, and one tank made it flash a lot more than usual.
almost two years ago i switched to only using shell. ive always used only 93 in cars that care.
almost two years ago i switched to only using shell. ive always used only 93 in cars that care.
Staging Lane
Joined: Jul 2016
Posts: 61
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I buy about 12 to 15,000 gallons per year and I say that never have I had a problem. 4 of my vehicles are turbo daily drivers and 3 of the 4 are tuned strong. Never a burnt plug, ring piston high engine temp DIC light on nothing. Maybe I'm jus lucky that the fuel gets used fast around here and doesn't have time to go bad. LOL
man o man, no where did I compare a OEM engine to a high dollar engine. I gave an example that no matter what engine you have if the tune is off and you subject that engine to too much load, it will not live. I don't studder nor do I type in tongues. Maybe the post should be read again you obviously missed everything.
Have you ever gotten a tank of bad gas? the only time ive seen the indicator of bad fuel is once in my evo. the evo will flash the CEL light when it sees more than like 5 knock counts, and one tank made it flash a lot more than usual.
almost two years ago i switched to only using shell. ive always used only 93 in cars that care.
almost two years ago i switched to only using shell. ive always used only 93 in cars that care.