Jump to content
SAU Community

Recommended Posts

Hi guys,

Not sure whats going on but on the way home from work this afternoon my powerfc showed a knock level of 65 when it came onto boost. I thought it may have been a one off so i took for another little run to see what it would do and it came up with a level of 73 and the engine light flickered i believe. Car records a knock level of 1 when first started at idle and when off boost around 6. The engine has only done around 15,000k's and is an rb30/25 conversion. I filled up this morning from a shell using there premium fuel and as far as i can recall didnt come onto boost untill i was on my home when the kock level spiked. Any suggestions on what it may be or anything to check?

Thanks in advance,

Matt.

Link to comment
https://www.sau.com.au/forums/topic/304396-high-knock-levels/
Share on other sites

Hey gfunk,

I am running a cataltic converter. I knocked 4 degrees out of the tune last night and took it for a hard boost and knock levels were fine. According to an experienced friend of mine it indicates the fuel is rubbish. Ill run this fuel out with the timing knocked back and keep the car off boost and fill up with some trusty bp fuel and let you know how it goes. Caltex you break my balls.

Yeah thanks mate. Am planning on using bp ultimate from now on after this incident. Any particular reason why i should use a few more tanks before i put the tune back to normal? Was planning on bumping it up a degree at a time after getting new fuel and giving it a boost and checking levels untill tune is back to normal on the next tank. Im no expert but from what i was told the knock levels i experienced in 2 short bursts yesterday is nothing to worry about in terms of damaging the engine? Of course having those knock levels everyday would be another story.

few tanks means there is no more of the other fuel left, but shouldnt matter much

the knocks wouldnt of done much to the engine, the knock needs to get over 80 to be considered a "true knock"

mine hits 80 one or two times a track day, its not the end of the world :P

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

    • Oh, that's grim. Something bad has been happening there.
    • Put an endoscope down the hole and saw this. Not quite all around the bore but a good 60% at least. Chin to the chest and towards further disappointments I guess.
    • 2 does "sort of" applies, maybe......but looking at what parts would be needed for the swap to get engineered, registered, and insured, and basically that's everything under the car, the modifications the make it legal would be problematic and horrendously expensive, all for a street car that just cruises around and hits a few twisty roads on the weekends Also, from looking at the NSW rules and Regs, with all modifications that is required just to make the car safe and not twist itself to pieces, and then actually get registered for street use, may still be impossible nowadays As for 1, when you add in a fresh engine, fresh transmission, rear cradle and diff, tailshaft, suspension, brakes, cooling, and all the other fabrication required, your probably looking at up to $100k to do it right, all for a 20 year old MX5 that is over engineered and you would never be able to actually use the power it has on the street, much like your beastie, which I love, but you actually track that thing and can use all of its powers in anger, in a safe environment  Hell, the old Bogan Cruise Ship had more power than I could use on the street, and in hindsight, I went a bit silly on that thing, it didn't really need the 500hp it had for what I actually used the car for, it was fun, but basically unusable on the street if you value your licence  As for cams, yeah, I'll probably book it in for them to get installed and tuned soonish, like next month after MX5 Mania are back at work....... and yes, I've already sent a email to bin the turbo quote and quote instead to install cams and a new Fluidampr balancer that will suit the 2.5 better than the OEM 2.0 balancer that is swapped over for the 2.5 install, as the balancer needs to get pulled to time the cams it's a while your in there sort of thing I did think a bit about flex fuel for a laugh, but being na, and no where really around locally anymore to get E85, I've binned that idea, so no sweet sweet corn smells are set for the car I wish E85 was more of a standard fuel, it's better for the environment, better for tuning, plus that sweet sweet smell we all love As for fitting in the family, that's not needed, as everyone in the family already owns a car that can seat 5 humans comfortably enough, the MX5 is "my toy" As for buying a car that is already built, nah, I would rather pick and choose my parts, I enjoy the process, and in the big picture, the additional cost is well worth the enjoyment, and the occasional frustration, I get out of doing it, albeit with other people spinning the spanners, and me, just paying the invoice 🤣
    • Excuse me, but 2) does apply 1) Would also apply if you consider how much is spent in the alternatives. Also there's the option of 3), buy one pre-built that you can put your family in (it's me, it's my car)   That said, I went on a ~500km drive the other day. I didn't use anything more adventurous than 3rd/4th gear at about ~3000RPM and 50% throttle and I was going as fast as anyone has any sense doing on a public road, with enough grip to the point where I didn't want to go any faster. I was obviously under the limit of the current car etc etc. MX5 with 2.5 N/A to achieve the same speed would be more fun for any road scenario. Maybe consider cams. I wouldn't boost it. The use case is just not there and it won't actually make the car more enjoyable unless you really do plan on wringing gears from 1st to 3rd (at least) at 100% WOT on a public road to 150+kmh.
    • Great if: 1. You had all of the money for everything else that is required  2. Lived in a country where you could actually do this and drive it legally on the road Sadly, neither applies to me As for the turbo, I am having second thoughts, mainly for engineering/registration legality reasons and insurance  Not saying I've finished doing stupid things that I probably should do to the MX5, but boost, and V8 engine swaps isn't on the cards Strange, but true 
×
×
  • Create New...