Jump to content
SAU Community

Recommended Posts

  • Replies 58
  • Created
  • Last Reply

Top Posters In This Topic

Avoid driving it dude, because lean afrs on cruise can and will burn your exhaust valves.

why would it be lean on cruise? i think your right with any boost it is leaning out, that must be why the light started flashing on mine, or maybe the tune.:whistling:

Here is how the intake was setup when it was stalling.

IMG_3970.jpg

This is how I had it afterwards to fix the stalling. I'm more convinced it was the ripples in the flex pipe than the extra length and bend, obviously had the air filter on for the test, this was taken before I put it on for the sake of the pic :).

IMG_3972.jpg

Its the angle the BOV enters, not the bend that causes the stalling imo. It looked like a nice intake until you ditched the airbox. :thumbsup:

I have to agree with scotty here

You can imagine the BOV just venting and bouncing around in all directions disrupting the flow.

When Scotty designed mine it dumps into the intake on an angle towards the turbo

Yet another thread full of mafia's condescending crap, i hope it makes you feel tough :thumbsup:.

Not really hey, I've seen the AFRs after many of these upgrades and I know for a fact that they run lean and its not advisable to drive them far or at all.

So, dribble your shit elsewhere.

why would it be lean on cruise? i think your right with any boost it is leaning out, that must be why the light started flashing on mine, or maybe the tune.:whistling:

I wondered the same thing, but I've seen it on a few cars.

I'm thinking that at 2,500rpm and above the turbo is spooling a tiny bit, making the air path easier into the motor. Being a bigger turbo, its able to help more air into the engine. Think about it, at those revs, the turbine is spinning at a notable speed. The compressor would be "helping" the air get into the engine easier on vacuum, allowing it to breathe easier.

What had been tuned to 14.5 - 14.7 afrs on cruise, I'd seen go above 15. Also caused the engine to run a little hotter at cruise due to being a little leaner.

Not all but a number of cars.

Oh no not a 5% rise in AFR's, how on earth are the exhaust valves going to survive that. Load is determined by the AFM, unless theres a leak or something else isnt working as it should then its fine to drive normally. Sure the AFR's arent always going to be EXACTLY the same as they were before but your not going to kill your motor by driving it around under light load. It takes AFR's upwards of 17-18:1 to do any damage to valves and pistons under light-medium load and you'd know all about it if it was that lean.

Not really hey, I've seen the AFRs after many of these upgrades and I know for a fact that they run lean and its not advisable to drive them far or at all.

So, dribble your shit elsewhere.

I wondered the same thing, but I've seen it on a few cars.

I'm thinking that at 2,500rpm and above the turbo is spooling a tiny bit, making the air path easier into the motor. Being a bigger turbo, its able to help more air into the engine. Think about it, at those revs, the turbine is spinning at a notable speed. The compressor would be "helping" the air get into the engine easier on vacuum, allowing it to breathe easier.

What had been tuned to 14.5 - 14.7 afrs on cruise, I'd seen go above 15. Also caused the engine to run a little hotter at cruise due to being a little leaner.

Not all but a number of cars.

i agree to this , the engine seems more powerful even without boosting compared to my old highflow i had, and that is significant , and its odd but i think true... and with cams i find it even more noticable..

Edited by SliverS2

Oh no not a 5% rise in AFR's, how on earth are the exhaust valves going to survive that. Load is determined by the AFM, unless theres a leak or something else isnt working as it should then its fine to drive normally. Sure the AFR's arent always going to be EXACTLY the same as they were before but your not going to kill your motor by driving it around under light load. It takes AFR's upwards of 17-18:1 to do any damage to valves and pistons under light-medium load and you'd know all about it if it was that lean.

No worries. So you just take your nose out of your ass shove your nose up the exhaust and have a sniff, and go "Yep, shes safe enough, thats about 16:1"

My whole point - Unless you have a wideband you have NFI. So is it worth the risk.

I've also seen cars cruise fine at 17:1 without a miss. Wonder how those exhaust valves are doing.

Who knows. But nah, she'll be right hey. Just spent $6k on a turbo upgrade, its just money. Who gives a f**k about the engine.

Its ok though, my cars will always be safe. And the people that listen to my advice.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Similar Content

  • Latest Posts

    • Bit of a pity we don't have good images of the back/front of the PCB ~ that said, I found a YT vid of a teardown to replace dicky clock switches, and got enough of a glimpse to realize this PCB is the front-end to a connected to what I'll call PCBA, and as such this is all digital on this PCB..ergo, battery voltage probably doesn't make an appearance here ; that is, I'd expect them to do something on PCBA wrt power conditioning for the adjustment/display/switch PCB.... ....given what's transpired..ie; some permutation of 12vdc on a 5vdc with or without correct polarity...would explain why the zener said "no" and exploded. The transistor Q5 (M33) is likely to be a digital switching transistor...that is, package has builtin bias resistors to ensure it saturates as soon as base threshold voltage is reached (minimal rise/fall time)....and wrt the question 'what else could've fried?' ....well, I know there's an MCU on this board (display, I/O at a guess), and you hope they isolated it from this scenario...I got my crayons out, it looks a bit like this...   ...not a lot to see, or rather, everything you'd like to see disappears down a via to the other side...base drive for the transistor comes from somewhere else, what this transistor is switching is somewhere else...but the zener circuit is exclusive to all this ~ it's providing a set voltage (current limited by the 1K3 resistor R19)...and disappears somewhere else down the via I marked V out ; if the errant voltage 'jumped' the diode in the millisecond before it exploded, whatever that V out via feeds may have seen a spike... ....I'll just imagine that Q5 was switched off at the time, thus no damage should've been done....but whatever that zener feeds has to be checked... HTH
    • I think Fitmit had some, have a look on there (theyre Australian as well)
    • Hah, fair enough! But if you learn with this one you can drive any other OEM manual. No modern luxury features like auto rev-matching or hillstart assist to give you a false sense of confidence. And a heavy car with not that much torque so it stalls easily. 
    • Actually, I'd say all three are the automatic option. Just the different trim levels. The manual would be RSFS, no? 
×
×
  • Create New...