No Crust Racing Posted April 29, 2017 Share Posted April 29, 2017 Need some ideas. R34 GTR. Car had 354rwkw with -9s at 24psi on e85. N1 manifolds, full 3.5 exhaust with no cat. Added 4bar sensor and kelford L182-A 264 cams and BC springs. Car is making less power than before and is laggier to make boost everywhere. 345rwkw or so on 19psi and will not make anymore boost, solenoid is max duty. I knew max boost would come down but not that much. Spikes to 25psi midrange but once the engine starts to breath it just falls away. Have tried lots of adjustment of cam timing, bench test wastegate actuators, and checked all the connections. I'm gonna go over and boost leak test it with him again and I considered bypassing BOVs for testing. I'm also going to remove intakes and inspect Comp wheels and free play. Given I'm sure I could hear a new turbo bearing/whistle type sound when it comes on boost, is this symptomatic of failing turbo bearing? The car had 2 boost leaks previously and I did a track day not knowing it had those leaks, worried I've cooked a turbo bearing? Other ideas welcome. Yes I know I should have put a single on it. Link to comment https://www.sau.com.au/forums/topic/470243-lack-of-powerlack-of-boost-rb26/ Share on other sites More sharing options...
r32-25t Posted April 29, 2017 Share Posted April 29, 2017 Link to comment https://www.sau.com.au/forums/topic/470243-lack-of-powerlack-of-boost-rb26/#findComment-7826581 Share on other sites More sharing options...
No Crust Racing Posted April 29, 2017 Author Share Posted April 29, 2017 I should add, it had this lag and power loss issue before the cams went in. This was one of the things we were chasing with this visit. Just before your get on your horse Link to comment https://www.sau.com.au/forums/topic/470243-lack-of-powerlack-of-boost-rb26/#findComment-7826582 Share on other sites More sharing options...
Piggaz Posted April 29, 2017 Share Posted April 29, 2017 Does it idle good? Link to comment https://www.sau.com.au/forums/topic/470243-lack-of-powerlack-of-boost-rb26/#findComment-7826583 Share on other sites More sharing options...
No Crust Racing Posted April 29, 2017 Author Share Posted April 29, 2017 Yes it idles perfectly as I also suspected that maybe the timing had been thrown out. He said it is revving cleanly it is just a boost issue. And if you remember from my build thread I was chasing a boost leak and that whistling sound before the cams went in. Would stuffed blow off valves have this kind of effect? Or does the vented pressure just end up back in the intake anyway and have no bearing on Max boost? Link to comment https://www.sau.com.au/forums/topic/470243-lack-of-powerlack-of-boost-rb26/#findComment-7826584 Share on other sites More sharing options...
djvoodoo Posted April 29, 2017 Share Posted April 29, 2017 A symptom of a cooked turbo bearing would be grey/white smoke yea? Link to comment https://www.sau.com.au/forums/topic/470243-lack-of-powerlack-of-boost-rb26/#findComment-7826597 Share on other sites More sharing options...
No Crust Racing Posted April 29, 2017 Author Share Posted April 29, 2017 If it's an oil seal yeah I guess?I'm talking more about bearing wear/pending failure.I can hear a whistle/whirring that wasn't there previously.Sounds like the whistle a turbo diesel 4wd makes as they spool. Link to comment https://www.sau.com.au/forums/topic/470243-lack-of-powerlack-of-boost-rb26/#findComment-7826599 Share on other sites More sharing options...
89CAL Posted April 29, 2017 Share Posted April 29, 2017 Have you checked end-float and side play on the turbo shafts? Link to comment https://www.sau.com.au/forums/topic/470243-lack-of-powerlack-of-boost-rb26/#findComment-7826614 Share on other sites More sharing options...
No Crust Racing Posted April 29, 2017 Author Share Posted April 29, 2017 They only had 7k on them when purchased and play was fine then, they have only done another 1000ks since. I will check them again tomorrow. My thought was that running a track day with a boost leak may have had them working too hard and caused an issue. What would I see from faulty BOVs? Link to comment https://www.sau.com.au/forums/topic/470243-lack-of-powerlack-of-boost-rb26/#findComment-7826615 Share on other sites More sharing options...
KiwiRS4T Posted April 29, 2017 Share Posted April 29, 2017 Test for boost leaks by blocking off the pipe (do you have 2 into 1?) and installing a tyre valve. Apply pressure - first up to 30 psi and then 40 psi and you will see if there is a leak. What kind of wastegate and what spring are you using? Link to comment https://www.sau.com.au/forums/topic/470243-lack-of-powerlack-of-boost-rb26/#findComment-7826618 Share on other sites More sharing options...
No Crust Racing Posted April 29, 2017 Author Share Posted April 29, 2017 Do you mean testing the BOVs?All piping to an from BOVs is factory.These are standard garret actuators that come on -9s so I think they are 1bar.They were both bench tested fine.If the BOVs were leaking I would've thought it wouldn't make 25psi in the midrange? Link to comment https://www.sau.com.au/forums/topic/470243-lack-of-powerlack-of-boost-rb26/#findComment-7826619 Share on other sites More sharing options...
No Crust Racing Posted April 29, 2017 Author Share Posted April 29, 2017 Dose Pipe suggested actuators. I think they are the standard 15.6psi ones that ship with those turbos. Tuner bench tested them, they both crack at 17psi, is that too early for a target boost of 24ish? They "were" working fine. This was them at purchase, those are the actuators. I will test BOVs, actuators preload, and shaft play tomorrow. Anything else? Link to comment https://www.sau.com.au/forums/topic/470243-lack-of-powerlack-of-boost-rb26/#findComment-7826630 Share on other sites More sharing options...
KiwiRS4T Posted April 29, 2017 Share Posted April 29, 2017 My suggestion for pressure testing was for the whole induction system - not just the bovs - also the piping, intercooler - all the connectors. I take it your boost control is by an aftermarket ECU and Mac valve. When you say the solenoid is at max duty - that should mean fully closed so no boost should be getting to the actuators...are you sure you have that right? I forgot you were using IWG. Maybe you need some heavier duty actuators such as the HKS ones. Link to comment https://www.sau.com.au/forums/topic/470243-lack-of-powerlack-of-boost-rb26/#findComment-7826641 Share on other sites More sharing options...
No Crust Racing Posted April 29, 2017 Author Share Posted April 29, 2017 I had pressure tested the entire intake previously when chasing boost leaks, up to 40psi. Will do it again to be sure. One thing a static test doesn't show is BOV leakage as anything going past is still in the same pipework, I'm just not sure what the symptoms are with faulty BOVs when the leak is past the seat and recirculating back into the intake. Haltech with 4bar sensor and Mac solenoid. If need be I'll wire the actuator flap shut to test it. Link to comment https://www.sau.com.au/forums/topic/470243-lack-of-powerlack-of-boost-rb26/#findComment-7826642 Share on other sites More sharing options...
fatz Posted April 29, 2017 Share Posted April 29, 2017 Gasket leak btw engine and tubos Link to comment https://www.sau.com.au/forums/topic/470243-lack-of-powerlack-of-boost-rb26/#findComment-7826643 Share on other sites More sharing options...
No Crust Racing Posted April 29, 2017 Author Share Posted April 29, 2017 Intake gasket is new, new gaskets on exhaust manifold and turbos. Should also show on boost leak test? Link to comment https://www.sau.com.au/forums/topic/470243-lack-of-powerlack-of-boost-rb26/#findComment-7826645 Share on other sites More sharing options...
No Crust Racing Posted April 30, 2017 Author Share Posted April 30, 2017 Found main issue, failed turbo.Thanks for the suggestions. Link to comment https://www.sau.com.au/forums/topic/470243-lack-of-powerlack-of-boost-rb26/#findComment-7826674 Share on other sites More sharing options...
Piggaz Posted April 30, 2017 Share Posted April 30, 2017 What's the plan now? Link to comment https://www.sau.com.au/forums/topic/470243-lack-of-powerlack-of-boost-rb26/#findComment-7826675 Share on other sites More sharing options...
No Crust Racing Posted April 30, 2017 Author Share Posted April 30, 2017 Considering I recently herniated a disc in my back and had a vasectomy on Friday, not much until I recover a bit. Leave it here. Get prices on options. Try not to rage? Link to comment https://www.sau.com.au/forums/topic/470243-lack-of-powerlack-of-boost-rb26/#findComment-7826680 Share on other sites More sharing options...
Piggaz Posted April 30, 2017 Share Posted April 30, 2017 Was it the rear snail that died? Link to comment https://www.sau.com.au/forums/topic/470243-lack-of-powerlack-of-boost-rb26/#findComment-7826682 Share on other sites More sharing options...
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