JamieP Posted May 19, 2009 Share Posted May 19, 2009 Nice choice on parts, interested to see what the billet wheel T67 is like, what .ar did you go with mate? chuck me a pm of how much and where from when you get a spare min mate. Quote Link to comment Share on other sites More sharing options...
jevansio Posted May 19, 2009 Author Share Posted May 19, 2009 (edited) Cheers guys, I read up on all the info on SF & Garrett's website, I totally understand the billet in itself gives no performance increase, its the new design of Precisions line up that give the increase. I nearly went for the safe T67DBB P-Trim but thought what the hell, may aswell be a guineapig pm's coming PS went for the 0.81 A/R (6765 billet) with the H-Cover (3" outlet as opposed to 2.5" to hook straight up with my 4 Row). T4 non-divided housing 3" vband Edited May 19, 2009 by jevansio (see edit history) Quote Link to comment Share on other sites More sharing options...
Wez Posted May 19, 2009 Share Posted May 19, 2009 Very nice matey, will be interested to hear how this tubby performs, I was looking at the smaller 6265 Quote Link to comment Share on other sites More sharing options...
jevansio Posted May 20, 2009 Author Share Posted May 20, 2009 Very nice matey, will be interested to hear how this tubby performs, I was looking at the smaller 6265 Cheers Wez, I've read that it's not until you push over 25 pounds (I assume that means PSI) that there is any difference between Precisions new & old design so I may not see any difference between a standard T67DBB, we'll have to wait and see. I saw some people (with enough boost) were pushing more power through a billet 6265 than a T67DBB with the spool of a T62 Quote Link to comment Share on other sites More sharing options...
dandan Posted May 20, 2009 Share Posted May 20, 2009 PS went for the 0.81 A/R (6765 billet) with the H-Cover (3" outlet as opposed to 2.5" to hook straight up with my 4 Row). Nice comp housing choice - same as mine (and SimonB as well I think). What was the reason for you 0.81 on the exhaust as opposed to a 0.68? I have both and am going to start with the 0.68 and see how it feels, it may be the cast manifold will allow me to bump up to the 0.81 with similar sppol to a 0.68 on a tubular....time will tell! Quote Link to comment Share on other sites More sharing options...
jevansio Posted May 20, 2009 Author Share Posted May 20, 2009 Nice comp housing choice - same as mine (and SimonB as well I think). What was the reason for you 0.81 on the exhaust as opposed to a 0.68? I have both and am going to start with the 0.68 and see how it feels, it may be the cast manifold will allow me to bump up to the 0.81 with similar sppol to a 0.68 on a tubular....time will tell! Cheers Dan, I went with the 0.81 as I run that on my GT4088R and the balance between spool & boost was perfect, I'm trying everything to reduce EGTs so didn't want to risk any increase by dropping a housing size on a bigger turbo than the GT4088R Quote Link to comment Share on other sites More sharing options...
mrgee2jz Posted August 22, 2009 Share Posted August 22, 2009 I have removed the turbo. Pics to follow. I spun it when I removed the compressor and it still stuck, it wasn't catching on the compressor housing. The oil everywhere is from me cranking the engine over with the oil feed removed to see if it was getting oil (I figured I couldn't do any more damage to it). The turbine is catching on the central cartridge (not the housing) when I spun it with the housing removed. I can't see how the housing can warp enough to cause that damage, there is nothing in the housing that goes anywhere near that part of the blade (unless I'm mistaken). Also checkout my manifold. I'm assuming this is fooked? Can anyone confirm? I guess I'm looking at new turbo & manifold now? (possibly full turbo kit) http://www.mkivsupra.net/vbb/attachment.php?attachmentid=92636&stc=1&d=1242472905 http://www.mkivsupra.net/vbb/attachment.php?attachmentid=92637&stc=1&d=1242472905 http://www.mkivsupra.net/vbb/attachment.php?attachmentid=92638&stc=1&d=1242472905 http://www.mkivsupra.net/vbb/attachment.php?attachmentid=92639&stc=1&d=1242472905 http://www.mkivsupra.net/vbb/attachment.php?attachmentid=92640&stc=1&d=1242472905 http://www.mkivsupra.net/vbb/attachment.php?attachmentid=92641&stc=1&d=1242472905 http://www.mkivsupra.net/vbb/attachment.php?attachmentid=92642&stc=1&d=1242472905 http://www.mkivsupra.net/vbb/attachment.php?attachmentid=92643&stc=1&d=1242472905 http://www.mkivsupra.net/vbb/attachment.php?attachmentid=92644&stc=1&d=1242472905 http://www.mkivsupra.net/vbb/attachment.php?attachmentid=92645&stc=1&d=1242472905 http://www.mkivsupra.net/vbb/attachment.php?attachmentid=92646&stc=1&d=1242472905 http://www.mkivsupra.net/vbb/attachment.php?attachmentid=92647&stc=1&d=1242472905 Hi. im pritty sure you will find all your problems were down to egt's. I have seen and done this a few times. normally either too much timing or not enough fuel couses this. If you look at the exhaust blades properly you can see that they have been melted, and the same goes for the manifold. although ideally you shouldnt use a divided manifold without a divided housing. i have also seen dented blades from foreign particles, eg, spark plugs ect entering the turbo or metal objects. and they normaly look like they have been hit, but not like this. Either your fuelling is/was inadequate or something very similar. Quote Link to comment Share on other sites More sharing options...
mrgee2jz Posted August 22, 2009 Share Posted August 22, 2009 Cheers Dan, I went with the 0.81 as I run that on my GT4088R and the balance between spool & boost was perfect, I'm trying everything to reduce EGTs so didn't want to risk any increase by dropping a housing size on a bigger turbo than the GT4088R If you dont mind me asking, before it melted the blades how was the spool up? coming on boost vs rpm and full boost vs rpm.?? once you melt the blades like this i know thwlag becomes much grater! but how was it before? Quote Link to comment Share on other sites More sharing options...
jevansio Posted August 22, 2009 Author Share Posted August 22, 2009 Pretty sure it's egts, my fueling is rich on purpose (around 11.0 at WOT in upper revs) The spool was great, can't recall off the top of my head exactly but around 4k it was on strong and pulled like that to over 7k. Quote Link to comment Share on other sites More sharing options...
vvteye Posted August 22, 2009 Share Posted August 22, 2009 Hi J. Are you up and running with the new kit yet or still saving the pennies? I'm still with my 4088R with a .95 housing and discussed dropping this with Dave at interpro to a .81 to improve the lag. He showed some reluctance on the grounds that this restricts the turbo, increasing pressure/temps and and if I had wanted to go down that route then I would be better off with a GT35. I assume he based this on his own experience and discussions with Garrett. I am planning to lift the boost when Ryan gets hold of it in a couple of weeks from 1.35 to 1.6 but you are making me very nervous. I have a turbo beanie and no water/meths kit (haven't a clue what they do!) so I guess I have every cause to consternate as it's my daily drive! I have an egt guage ready to go in so can report these figures back soon. Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted August 22, 2009 Share Posted August 22, 2009 I thought it was pretty much well established that the bulk of the GT4088 failures was due to high EGTs, compounded by unsuitable exhaust housings (wrong material) and the effect being that the housing distorts and melts to a very small degree, thus eroding/melting the exhaust turbine. I think its also pretty much established that those of us who have the Precision turbo exhaust housings have no problems, or have never seen high EGTs for whatever reasons, IE mapping, cam timing etc. Quote Link to comment Share on other sites More sharing options...
jevansio Posted August 22, 2009 Author Share Posted August 22, 2009 I don't think its correct to say people who have Precision hosuings have no problems, I've bust 2 GT4088Rs and both have had Precision housings. I believe my probs are soley EGT related, and it's not possible for the hosuing to warp to the extent that would be required to cause that damage to the baldes Quote Link to comment Share on other sites More sharing options...
jevansio Posted August 22, 2009 Author Share Posted August 22, 2009 Hi J. Are you up and running with the new kit yet or still saving the pennies? I'm still with my 4088R with a .95 housing and discussed dropping this with Dave at interpro to a .81 to improve the lag. He showed some reluctance on the grounds that this restricts the turbo, increasing pressure/temps and and if I had wanted to go down that route then I would be better off with a GT35. I assume he based this on his own experience and discussions with Garrett. I am planning to lift the boost when Ryan gets hold of it in a couple of weeks from 1.35 to 1.6 but you are making me very nervous. I have a turbo beanie and no water/meths kit (haven't a clue what they do!) so I guess I have every cause to consternate as it's my daily drive! I have an egt guage ready to go in so can report these figures back soon. Hey Jon, not up and running yet, there is a massive delay on the units, been waiting around 10 weeks for mine now I would get the EGT probe in pre turbo and based on my experience keep the EGT's no higher than 850, I've been seeing 900-950 (5th-6th gear) and that was enough to cause the damage to mine I believe Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted August 22, 2009 Share Posted August 22, 2009 (edited) I don't think its correct to say people who have Precision hosuings have no problems, I've bust 2 GT4088Rs and both have had Precision housings. I believe my probs are soley EGT related, and it's not possible for the hosuing to warp to the extent that would be required to cause that damage to the baldes Both of your's Precision exhaust housings then, didn't realise that, just how high did your EGTs go then? Has anyone else had a problem with a GT4088 with Precision housing? I'm afraid both Turbo Technics and Turbo Dynamics would disagree with that statement, as the non precisions housings IE Garrett, are made of the wrong material to withstand the high EGTs of a petrol engine, and both of their opinions are that the housing is capable of warping enough to cause damage, but the main consensus is that the housing actually melts, which causes the main damage to the turbine, however i do agree that the source of the problem is high EGTs for whatever reason. Edited August 22, 2009 by Tricky-Ricky (see edit history) Quote Link to comment Share on other sites More sharing options...
jevansio Posted August 22, 2009 Author Share Posted August 22, 2009 Yeah both of them, over 900, 950 on occassion If the hosuings warp , they would remain warped after cooling? Is there any photographic evidence of the warped hosuings or is it just an expert opinion? Quote Link to comment Share on other sites More sharing options...
vvteye Posted August 22, 2009 Share Posted August 22, 2009 Hey Jon, not up and running yet, there is a massive delay on the units, been waiting around 10 weeks for mine now I would get the EGT probe in pre turbo and based on my experience keep the EGT's no higher than 850, I've been seeing 900-950 (5th-6th gear) and that was enough to cause the damage to mine I believe Thanks for the advice, is there a wholly agreed standard place where the EGT probe should go as I've heard 6th runner, 6inches from the hotside, etc. Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted August 22, 2009 Share Posted August 22, 2009 Yeah both of them, over 900, 950 on occassion If the hosuings warp , they would remain warped after cooling? Is there any photographic evidence of the warped hosuings or is it just an expert opinion? Just opinions over the phone when i spoke at length over the issues with GT4088s failing, but they did say they had seen it, so who am i to argue with a well respected turbo specialist:search: Quote Link to comment Share on other sites More sharing options...
jevansio Posted August 22, 2009 Author Share Posted August 22, 2009 I'll believe it when I see it, going off the damage to the turbine blades I've seen from my (and other failures), the hosuing would have to be the shape of a blob of plastercine to cause that much damage, and I'm sure if that's the case pics would be all over. As far as I am concerned if it's their opinion, it never happened unless they can provide pics & damaged units. To be fair when this whole saga kicked off (to which I am concened as it's happend to me twice), Precision were deemed shit, & the people with Garrett units looked down their noses at the "poor boys" who bought the shitty Precision units. I don't understand now why you say the Garretts are the inferior units & Precsion have the better hot sides. I stand by my thoughts, EGT's cause these failures due to nibbling the blades, the hot side warping is a myth. I will believe otherwise when I see a hotside warped so bad it can nibble 10mm from a turbine blade. Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted August 22, 2009 Share Posted August 22, 2009 I'm inclined to agree, but i subscribe mostly to this explanation, not just because its Chris Wilson, but i have also had the same replies from turbo specialists, including the warping bit as well. I needed to have a meeting with my turbo suppliers over a new project, and having the head Honcho's ear for a while I asked about the current crop of failures of 4088 Garrett turbos. IMO you can take the following as Gospel. The 4088 turbos listed and sold by Garrett in the US are DAF truck turbos. Whilst the turbine wheel itself should withstand EGT's seen in a properly fuelled and mapped gasoline engine the exhaust housing won't. It's not made of Ni-Resist cast iron, which high performance gasoline turbos should have. The housing is eroding and superheated incandescent particles in turn erode the turbine wheel. To compound matters the stock 4088 has a 6 bolt turbine housing, which is unusual. Sellers in the US have Chinese cast V band turbine housings made afor two and six, and fit these. These housings are even less heat tolerant than the stock Garrett ones, and not only erode, but warp and distort, sometimes to the extent the turbine wheel catches, or the housing leaks. The only answer is to either fit them to diesels or sell / bin them and get a turbo that has the proper high performance Ni-Resist (trade mark name for high nickel content cast iron) turbine housing. To quote, you get what you pay for, 900 quid buys a proper turbo, 500 quid buys an improper turbo.... HTH. Quote Link to comment Share on other sites More sharing options...
jevansio Posted August 23, 2009 Author Share Posted August 23, 2009 (edited) I guess I'm a cynic I can believe the "eroding and superheated incandescent particles" theory definately, I'm just having trouble swallowing the warping bit. I did have a big post typed up but I lost it, I'm off down the club so will try & put it together when I come back (depending on how many pints I've had ) Basically I found all the failure pics on this forum and IMHO the turbine blade damage could not be caused by warping. Reasons off the top of my head: 1. Inside the turbine hosuing there is only 1 area that can cause that damage, for that to warp that far the housing would be so badly mishaped the turbine wheel could not fit inside it (nevermind spin). 2. All blades are damaged in different shapes on the same turbine, warping would make the same profile on each blade. The idea of the hosuing eroding is interesting though, look at the closeup pics of my housing earlier in the thread, does it look to you like thin slivers of material have come off the hosuing. Just to re-iterate, I'm not being an ass here on purpose, I just want to get to the truth ("You can't handle the truth" I hear you shout ) PS anyone know where that post was showing a perfect GT4088 that had just been taken off? Sure it was Charlie Edited August 23, 2009 by jevansio (see edit history) Quote Link to comment Share on other sites More sharing options...
b_have Posted August 23, 2009 Share Posted August 23, 2009 'twas me Infact I just removed it again since having a boost issue at Suprapod (couldn't get above 1.3 bar) thinking I had burned the hotside. Still looks as new. Quote Link to comment Share on other sites More sharing options...
jevansio Posted August 23, 2009 Author Share Posted August 23, 2009 Cheers bud Quote Link to comment Share on other sites More sharing options...
b_have Posted August 23, 2009 Share Posted August 23, 2009 This was the cause of the boost problem (I'm suprised it made 1.3 bar like this) Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted August 23, 2009 Share Posted August 23, 2009 Like i said i agree, and thinking about it logically, i can see no way that any of the damage i all of the pics posted on this board could be down to warping, but this was related to me over the phone, you never know it may have been a different model the guy was thinking of, they also make mistakes;) I should have posted pics of mine when i took it off for a rebuild, (weak seals) the exhaust turbine was perfect, however i had only run it at 1.35 BAR and never seen EGTs over 800c. Quote Link to comment Share on other sites More sharing options...
paul mac Posted August 23, 2009 Share Posted August 23, 2009 I don't think its correct to say people who have Precision hosuings have no problems, I've bust 2 GT4088Rs and both have had Precision housings. as a point of interest i contacted two well known turbo re-builders with regard to giving my Precision T61 a "refresh", both refused my bussiness, the first without reason the second was more forthcoming stating the quality of Precisions turbos was not condusive to them being able to do a quality job or indeed offer a warranty, it was nothing to do with parts availability as i offered to get the bits myself, i think this speaks volumes Quote Link to comment Share on other sites More sharing options...
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