Your exactly right...when a turbo motor is under boost there is a ton of fuel and compression in it. It comes a point where the temperature rises to dangerious levels and "fuel" is what cools things.{Intercooler or water injection helps some as well} The reason people use c-16 is that it burns very slow and resists preignition to a point. Running a turbo engine on big boost at 12.7:1 for a long pull[1 mile] with c-16 and an intercooler, timing pulled and your still toast. Call and talk with Velocity, RCC, or NLR and they will tell you the same.Which is why I think you could pull timing. Heat is power. That is why we add more fuel and compression to engines. The more fuel being burned, the more heat there is. The more heat there is the less timing "advance" is needed to complete the cycle.
I thought that was the reason we coat pistons and headers also. To keep the heat in the chamber to promote velocity and combustion efficiency.
I would agree that there is a point when lean is "too lean", but 12.2 doesn't seem like that is the point.
I would have to hear a better argument than "lean is heat". I'm not picking on anyone. I'm just saying that is not a very descriptive response.![]()
Your exactly right...when a turbo motor is under boost there is a ton of fuel and compression in it. It comes a point where the temperature rises to dangerious levels and "fuel" is what cools things.{Intercooler or water injection helps some as well} The reason people use c-16 is that it burns very slow and resists preignition to a point. Running a turbo engine on big boost at 12.7:1 for a long pull[1 mile] with c-16 and an intercooler, timing pulled and your still toast. Call and talk with Velocity, RCC, or NLR and they will tell you the same.
he was using the mile as an example
but he is also referring to having an intercooler and everything else and still burning up
i know of people who log there intakle temps in the low 200's at the end of the 1/4 mile and the intake temps also are going to burn things up
and that also with the a/f and the compression and all that is in your stock motored busa will burn parts up
i lost a motor at 8 psi at 9500 rpms in 6th and all 4 were burnt up
it only take a millisecond to burn the stock pistons
even ryan posted in his last post he wouldnt trust the stock setup at anything over 6 psi and you brag of a stock motor and yet you run it that lean?
reread his post about stock motor stock pistons
should i post pictures of a set of burn pistons? (not tryin to be a smartalik just saying its not the safest)
and my prostreet bike i wont run that lean sorry just wont
i like to keep some parts
Your exactly right...when a turbo motor is under boost there is a ton of fuel and compression in it. It comes a point where the temperature rises to dangerious levels and "fuel" is what cools things.{Intercooler or water injection helps some as well} The reason people use c-16 is that it burns very slow and resists preignition to a point. Running a turbo engine on big boost at 12.7:1 for a long pull[1 mile] with c-16 and an intercooler, timing pulled and your still toast. Call and talk with Velocity, RCC, or NLR and they will tell you the same.
Hey man it's a real nice bike you have there, we just don't want you to blow it up. I've seen a stock busa last 20,000 miles on a fat map at 12 psi. I also saw one let go at 200 miles on 6 psi because he was lean...Just tring to help.
First of all, Vtakt that is a sweet bike! I'm just curious of the breaking point of a "stock" motor. Your post insinuates that a stock motor is fine at the A/F ratio, boost, ect because of the AEM. I don't dispute that and your times make a strong statement. I think keeping the bike together will make a stronger statement.I'm interested in what happens and will follow very closely if you post results and times.
So what are you calling a "maximum safe" A/F ratio. Is 11.8 what is typically tuned for?
Vtakt be sure to post some more vids this year when you make some runs! I would love to see some high 7's out of that bike!!
Hey man it's a real nice bike you have there, we just don't want you to blow it up. I've seen a stock busa last 20,000 miles on a fat map at 12 psi. I also saw one let go at 200 miles on 6 psi because he was lean...Just tring to help.
I'd say your right. It's a street bike that he only "hammered" for short intervals. The occasional big pull was done but not often. He just enjoyed that first "boost" hit I think...I love reading stuff like this...
I bet in reality you saw a bike with the capacity to run 12 psi, last 20,000 miles.
He rarely ever actually hit 12 psi during that time i bet.
The reason most everyone tunes a bike at 11.5:1-11.8:1 is because the extra fuel aids in cooling the intake charge and lowering combustion temps. In our liq/air Ultra kits you can tune them at 12:1 safely. Now a race bike that runs for about 8.5 seconds then shut down, may live for a while at leaner airfuel settings, but it is definitely on the edge, intake temps will be fairly high, and the engine life will be much shorter.
In my own opinion I do not see any reason to run slightly lean, increasing the chances of detonation and engine failure. Please keep in mind these little bits of information I am sharing is not speculation, or opinion. We have done years and years of R&D, build 20 plus turbo engines per year, sell hundreds of turbo systems per year, and recommend 11.8:1 on every kit. We also continue to tune turbo bikes daily, constantly working to improve our own kits and also make improvements to customers bikes that have competitors kits installed as well.
All this is for your information only, you are most welcome to use it or ignore it, I have only posted it for your benefit.
Richard
Hey Ryan does this AEM unit have inputs for air temp, water temp, or baro pressure. If so can compensation tables be created to compensate for temperature and elevation changes? This is the biggest probelm with stage 1 and 2 turbo systems now is that they do not adjust for these factors, a standalone bike using a Motec or Magetti Marrelli can obviously run comp. tables but they are a lot more money then a lot of people want to spend
Richard