Guest darrenp Posted October 30, 2008 Share Posted October 30, 2008 OK fellas I’m after some advice or information. I have just done a rebuild plus hi-flowed my JDM turbos. Basically after 3000k both the turbos have shat themselves due to what looks like oil starvation to the bearings while under boost, according to the turbo builder who is looking for reasons not excuses. When engine was cranked over on starter the oil feeds were pumping out at least 400ml in 15 secs so my mechanic thinks there are no oil pump issues or blockages up to that point. The turbo shop want me to drop the sump (now that’s a bastard of a job) and check the pickups, but you would think if the pickup was getting blocked it would have happened during all the Dyno tuning or at least given me issues before the 3000km mark. Engine has been run in properly and now running on 10W-30 Mobil full synthetic. The engine builder I used I’m sure suffers from an almost obsessive compulsive disorder as far as cleaning and checking goes so I really don’t think it was anything he has or hasn’t done. Prior to the turbos blowing the motor was really strong and pulling about 340rwkw at 1.4 bar at 7000rpm. Even when turbos blew the motor still ran and idled fantastic. If anyone here has any clues or thoughts please post back here and I will keep checking as I am not keen on spending more money having 2 turbos rebuilt and then have it happen again. Thanks in advance Darren Quote Link to comment Share on other sites More sharing options...
Wez Posted October 30, 2008 Share Posted October 30, 2008 1.4bar on JDM turbos? What does hi-flowing the JDM turbo do, what is this? If the turbos are still ceramic as they come stock, 3000 miles at 1.4bar seems pretty resonable, 1.2bar is often regarding as the safe limit on the JDM units. Quote Link to comment Share on other sites More sharing options...
Scott Posted October 30, 2008 Share Posted October 30, 2008 Where did the 1.4 idea come from? I'm guessing it was noone on this forum? Quote Link to comment Share on other sites More sharing options...
tDR Posted October 30, 2008 Share Posted October 30, 2008 Yep 1.4bar is just too high for ceramics. If 'hi-flowing' them means actually changing them over to steel internals - our 'hybrids' then theoretically you can run more boost but tbh they are out of their efficiency range over 1.2bar and you're into diminishing gains and outputting superheated air. Hybrids seem to shit themselves 9/10 times going by the history of them on here whilst I've been a member. Suggest going single instead. Cheers, Brian. Quote Link to comment Share on other sites More sharing options...
Guest darrenp Posted October 30, 2008 Share Posted October 30, 2008 (edited) They have steel wheels all Ceramic wheels are gone. Usually I keep them maxed to 1.3 bar with the wheels I have installed but boost was still climbing at 1.4Bar. The 1.4Bar was our limitation not the turbos and the builder of the turbos who is recognized as one of the best in Australia said they would be fine up to 26lb but start to fall off the curve at the 20 - 22lb mark. I am running a Boost Controller, Autronic Stand alone ECU, 650 injectors,Bosch upgrade fuel pump. Basically every thing strong and built to last and running an extremely safe tune. The issue is more to do with oil to the bearings at boost. The turbo builder said it looks like an oil surge issue ( he builds turbo setups for some incredibly powerful road and off road vehicles from racing trucks to International rally cars) but the car has only seen Dyno and normal road use, no track or strip work at all. My mechanic or myself have never heard of 2J's suffering from oil surge even on track days so its a real head scratcher. Replacing the oil feed lines even though they seem clean and obstruction free. I dont want to go down the single route as the Road Authority here in Australia tend to take you out the back for an arse reaming if your car looks even slightly non standard so I was going down the stealth road. My goal was only to make 300 rwkw which has been done easy ,in fact it makes 296 at 5500rpm and has been built to handle 7500rpm with a self set max of 7000rpm. I am running the Turbos in Parallel mode not sequential if that makes any difference. Im devestated as you would imagine so really hope someone here can shed some light on what may have caused the problem before I shell out more money for new turbos. Cheers Darren Edited October 30, 2008 by darrenp (see edit history) Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted October 30, 2008 Share Posted October 30, 2008 If the sump pick up oil strainer is so blocked as to stop enough oil flow to the *turbos* the bearings in the engine will have also failed. . Sounds like the turbos were over speeded. 1.4 bar is far too much for stock ceramic turbos, they'll be revving their little hearts out. Stock ceramics have a much longer normal service life than stock UK / US steel ones, at stock boost. There are serious issues running in parallel mode, IMO. As an aside, if one compared laws on modified cars on the road, in Oz V New Zealand, which country is the more relaxed? (Wishful thinking in case I can persuade `er indoors to leave this sinking ship ) Quote Link to comment Share on other sites More sharing options...
Guest yiros Posted October 30, 2008 Share Posted October 30, 2008 If the sump pick up oil strainer is so blocked as to stop enough oil flow to the *turbos* the bearings in the engine will have also failed. . Sounds like the turbos were over speeded. 1.4 bar is far too much for stock ceramic turbos, they'll be revving their little hearts out. Stock ceramics have a much longer normal service life than stock UK / US steel ones, at stock boost. There are serious issues running in parallel mode, IMO. As an aside, if one compared laws on modified cars on the road, in Oz V New Zealand, which country is the more relaxed? (Wishful thinking in case I can persuade `er indoors to leave this sinking ship ) Turbos are far from stock. The photo below is a comparison between stock ceramic JDM and Darren’s hi flowed (Hybrid) turbos. The wheels are Mitsubishi (Trust) 20G TD06s. Possibly an over speed issue however many guys here in Oz push their stock ceramic JDM turbos above 18 psi with only wheel delamination problems, not bearing problems. Similar hi-flowed setups has been performed various times with no known issues. Please explain why parallel setup causes more problems? Our turbo guy is the best in the business. Other than being an ex-racer, he has worked with Formula 1 teams (back in the 80’s) and uses a ex F1 turbo balancing machine. Picture of my turbos with GT28 wheels. I am running these in the conventional parallel setup, i.e. separate waste gates, separate dumps (4-2-1 setup). We expect these to out perform a moderate single conversion plus look stealthy. To answer your question re Oz & NZ – Too hard to answer as every state in Oz has different rules. Some states make no sense i.e. You are allowed to make 2 or 3 induction modifications i.e. Air filter, FMIC etc with minimal restrictions – how stupid is that? Our state says you can do what ever you like providing emissions and safety etc meet the relevant Australian Standards at the time of manufacturer and need to be approved by an automotive engineer… Being an engineer and working for a Tier 1 OEM supplier, I know which rules make more sense… Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted October 30, 2008 Share Posted October 30, 2008 Having run hybrids in parallel, i can't see any problems with this, if anything i would have said they are not likely to suffer overspeed as much as in sequential mode, but i would ask if the spindles and bearings where increased in size? as this might be a factor in this, as a smaller diameter spindle/shaft would suffer more friction. Even so i doubt that this alone would cause failure, i would suspect an oil supply glitch. One other question, what where the max EGTs, and where was the reading taken? Quote Link to comment Share on other sites More sharing options...
tDR Posted October 30, 2008 Share Posted October 30, 2008 That's some interesting work you're doing over there with the stock turbo housings - 2x effective TD06 20G's must be able to chuck out a fair amount of power? Any idea the horsepower ability with that kinda setup or with the T28 wheels? Also what's the spool like, when's full boost? Very different to hybrids here... Quote Link to comment Share on other sites More sharing options...
Guest yiros Posted October 31, 2008 Share Posted October 31, 2008 (edited) Having run hybrids in parallel, i can't see any problems with this, if anything i would have said they are not likely to suffer overspeed as much as in sequential mode, but i would ask if the spindles and bearings where increased in size? as this might be a factor in this, as a smaller diameter spindle/shaft would suffer more friction. Even so i doubt that this alone would cause failure, i would suspect an oil supply glitch. One other question, what where the max EGTs, and where was the reading taken? Good suggestion re EGTs. I asked the question and no measurements were taken. If EGTs were a problem, the exhaust wheels would show signs of excess heat would they not? Both the mechanic and turbo specialist have inspected the turbos and there are no visible signs of heat stress. The tune was absolute perfect and very safe. Autronic SM4 is rated very highly and people in Oz compare Autronic with Motec. Only issue with Autronic is support sucks big time. The turbo specialist is 100% certain the failure is caused by oil starvation to the turbos. Darren’s cars is running a new oil pump and the engine is still running strong (even with the blown turbos). I spoke with the mechanic this morning and he will be cutting the 200,000km old oil turbo feeds to see if there are any signs of restriction (similar to arteries blocking up over time). I have suggested that an oil analysis be performed (oil was changed a day or two prior and yes I said to check the levels) to see if we can find any metal particles such as bearings etc prior to pulling the sump. That's some interesting work you're doing over there with the stock turbo housings - 2x effective TD06 20G's must be able to chuck out a fair amount of power? Any idea the horsepower ability with that kinda setup or with the T28 wheels? Also what's the spool like, when's full boost? Very different to hybrids here... Both the 20G TD06 and GT28 are capable of around 200rwkw each so based on this we are hoping for mid 300rwkw. Darren has measured around 340rwkw on a safe tune (Dyno Dynamics). Main problem is the cars was lighting up the rears at 6,000 rpm and difficult to tune or get an accurate ready. I am hoping for more as I have gone an extra 4 steps:- i.e. slightly more aggressive turbos, race porting and polishing with 1mm valves, forged bottom end and individual dumps from the back of both turbos. Edited October 31, 2008 by yiros (see edit history) Quote Link to comment Share on other sites More sharing options...
tDR Posted October 31, 2008 Share Posted October 31, 2008 Both the 20G TD06 and GT28 are capable of around 200rwkw each so based on this we are hoping for mid 300rwkw. Darren has measured around 340rwkw on a safe tune (Dyno Dynamics). Main problem is the cars was lighting up the rears at 6,000 rpm and difficult to tune or get an accurate ready. What do those figures equate to in real money? Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted October 31, 2008 Share Posted October 31, 2008 200 Khw = 268 BHP 300 Khw = 402 BHP Quote Link to comment Share on other sites More sharing options...
Guest yiros Posted October 31, 2008 Share Posted October 31, 2008 (edited) What do those figures equate to in real money? Not sure what you mean but the rest of the world have adopted the metric system… 1HP = 0.75kW If you are talking about ‘bang for buck’, to build these turbos cost around AU$1,500 each. Edited October 31, 2008 by yiros (see edit history) Quote Link to comment Share on other sites More sharing options...
tDR Posted October 31, 2008 Share Posted October 31, 2008 Not sure what you mean but the rest of the world have adopted the metric system… 1HP = 0.75kW If you are talking about ‘bang for buck’, to build these turbos cost around AU$1,500 each. Some things in life should always remain the same: 1. Horsepower - BHP 2. Torque - lb/ft 3. Speed - MPH 4. Distance - Miles Anything else is just wrong where cars and travelling are concerned So you're talking maybe 500 BHP (340rwkw) at the fly tops with one of these turbo setups - not particularly great IMO, especially as you don't retain the sequential setup. Then again £1,250 for the pair rebuilt is good value - there's no doubt other fabrication involved so I'm guessing we'd be looking at a minimum of £1,500 to get one of these setups working, plus delivery to here. It would be worthwhile as a viable alternative to going small single if they were reliable... Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted October 31, 2008 Share Posted October 31, 2008 Some things in life should always remain the same: 1. Horsepower - BHP 2. Torque - lb/ft 3. Speed - MPH 4. Distance - Miles Anything else is just wrong where cars and travelling are concerned So you're talking maybe 500 BHP (340rwkw) at the fly tops with one of these turbo setups - not particularly great IMO, especially as you don't retain the sequential setup. Then again £1,250 for the pair rebuilt is good value - there's no doubt other fabrication involved so I'm guessing we'd be looking at a minimum of £1,500 to get one of these setups working, plus delivery to here. It would be worthwhile as a viable alternative to going small single if they were reliable...[/quote 340KW equates to 455 BHP, so really no more than a lot of hybrid setups available in this country, when set up and tuned properly. Quote Link to comment Share on other sites More sharing options...
Guest yiros Posted October 31, 2008 Share Posted October 31, 2008 So you're talking maybe 500 BHP (340rwkw) at the fly tops with one of these turbo setups - not particularly great IMO, especially as you don't retain the sequential setup. Then again £1,250 for the pair rebuilt is good value - there's no doubt other fabrication involved so I'm guessing we'd be looking at a minimum of £1,500 to get one of these setups working, plus delivery to here. It would be worthwhile as a viable alternative to going small single if they were reliable... Once we find the cause of the oil starvation, reliability shouldn’t be a problem. Yes the numbers aren’t huge but we weren’t chasing huge numbers – plus the car looks stock. Let’s face it, why does anyone need more than 300rwkw for a street car other than bragging rights? Darren’s car was making over 200rwkw at 4,000 rpm. Plenty of mid range grunt with nice pull all the way to redline. Sure it doesn’t have huge top end power but we are more interested in the power curve – which we don’t have a copy to show you guys (yet). Cheers Quote Link to comment Share on other sites More sharing options...
Scott Posted October 31, 2008 Share Posted October 31, 2008 Some things in life should always remain the same: 1. Horsepower - BHP 2. Torque - lb/ft 3. Speed - MPH 4. Distance - Miles Anything else is just wrong where cars and travelling are concerned So you're talking maybe 500 BHP (340rwkw) at the fly tops with one of these turbo setups - not particularly great IMO, especially as you don't retain the sequential setup. Then again £1,250 for the pair rebuilt is good value - there's no doubt other fabrication involved so I'm guessing we'd be looking at a minimum of £1,500 to get one of these setups working, plus delivery to here. It would be worthwhile as a viable alternative to going small single if they were reliable... 340KW equates to 455 BHP, so really no more than a lot of hybrid setups available in this country, when set up and tuned properly. 455 at the wheels from hybrids? Not seen that anywhere on here. Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted October 31, 2008 Share Posted October 31, 2008 455 at the wheels from hybrids? Not seen that anywhere on here. Missed the "at the wheels" bit,in that case if they are using inducer/exducers big enough to achieve that sort of power on std size spindles, i am not overly surprised that the turbos failed. Quote Link to comment Share on other sites More sharing options...
tDR Posted November 1, 2008 Share Posted November 1, 2008 Hence I 'guesstimated' 500bhp fly I think a small single on stock cams will produce a nicer power curve and have more peak power. Quote Link to comment Share on other sites More sharing options...
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