Wez Posted July 28, 2007 Share Posted July 28, 2007 It is a divided housing .96 ar, this 4088, whereas the 35 I have is '68. maybe that would have some bearing compared to yours.. what 'ar are you running? .96 sounds big, did you have a choice? Quote Link to comment Share on other sites More sharing options...
Jake Posted July 28, 2007 Author Share Posted July 28, 2007 .96 with a divided tang isn't big (or clever:)). .96A/R For a non-divided is quite large - but it's what I have on my non-DBB 4088 and it's fine, no problem with throttle response here. Quote Link to comment Share on other sites More sharing options...
Wez Posted July 28, 2007 Share Posted July 28, 2007 Mike it might be an idea to get an approved mapper to check out whats going on as I recall you are doing this with the ECU remapping itself. I guess you have already checked the fueling but what about ignition as this can have great affects on how a turbo spools. Quote Link to comment Share on other sites More sharing options...
dandan Posted July 28, 2007 Share Posted July 28, 2007 Mike what AFR's have you got at full throttle from 2000rpm up until she's making let's say 0.5bar? Quote Link to comment Share on other sites More sharing options...
TLicense Posted July 28, 2007 Share Posted July 28, 2007 .96 sounds big, did you have a choice? pffft. .96 is teeny. You should try 1.48.... Now that is big! Quote Link to comment Share on other sites More sharing options...
dangerous brain Posted July 28, 2007 Share Posted July 28, 2007 I am beginning to get a grasp of what all this stuff means now courtesy of garretts technical info from their site http://www.turbobygarrett.com/turbobygarrett/tech_center/tech_center.html Its still all very confusing though. Especially as the same firm has different turbo name types. I thought it was as simple as a T61 is so so size and the T67 is bigger than the T61 but each of those two turbo's come with a variety of compressor and exhaust size options that look to all intents and purposes that you could have a T61 and a T67 the same size? Even the gt4088 has all different sizes. Replacing my T04R with something else seems very complicated a choice now. I can post the dyno sheets from my car from both thors hub dyno and the one dan turner uses in Bletchly when next I am in the UK Quote Link to comment Share on other sites More sharing options...
Wez Posted July 28, 2007 Share Posted July 28, 2007 pffft. .96 is teeny. I think mine is a .70a/r Quote Link to comment Share on other sites More sharing options...
Jake Posted July 28, 2007 Author Share Posted July 28, 2007 Well mine put down 455 bhp at the hubs at JAE on thors hub dyno and 458 at the crank calculated using transmission run down on the dyno at my tuners the day after. Obviously a bit of a difference. That's about normal for Thor. What was it at the wheels at Marlin in Bletchley? I can post the dyno sheets from my car from both thors hub dyno and the one dan turner uses in Bletchly when next I am in the UK That would be intesting. Cheers. Quote Link to comment Share on other sites More sharing options...
Mike B Posted July 28, 2007 Share Posted July 28, 2007 Mike what AFR's have you got at full throttle from 2000rpm up until she's making let's say 0.5bar? I will check for you. from memory she sits around 13 until it kicks in then it goes to 10.5 recovering to a steady 11.3 all the way to the redline. I have done a tank of fuel in the car now and it is settling down, it is actually getting better... but it's still no hare trigger,,, when she goes.. holy cow she goes! still quite unreal just how much power there is in 3rd and 4th. .96 sounds big, did you have a choice? no, the GT488R smallest housing available is a .96... they used to do a .85 non divided housing which Jamie P used, his replacement tubby came with a .96 I believe so it would be interesting to say what he thinks... I would have had the .85 if I had had a choice. so I have jumped from .68 housing to a .96.. maybe that explains a lot? Quote Link to comment Share on other sites More sharing options...
Homer Posted July 28, 2007 Share Posted July 28, 2007 It is a divided housing .96 ar, this 4088, whereas the 35 I have is '68. maybe that would have some bearing compared to yours.. what 'ar are you running? It's a 0.68 ar... Quote Link to comment Share on other sites More sharing options...
Mike B Posted July 28, 2007 Share Posted July 28, 2007 It's a 0.68 ar... That's teeny tiny for a big tubby.. that might be the answer then...? Does your power drop slightly when you hit the upper rev range at all or is it solid right up to the redline? Quote Link to comment Share on other sites More sharing options...
Homer Posted July 28, 2007 Share Posted July 28, 2007 Does your power drop slightly when you hit the upper rev range at all or is it solid right up to the redline? Mine starts to tail off around 6200rpm, but I still have the stock jspec cams in! It's still 'pulling' though, but you can feel it dropping. From what others have said they pull pretty much to redline with some higher lift cams (Ian C I think has some good data on this). Quote Link to comment Share on other sites More sharing options...
jevansio Posted July 28, 2007 Share Posted July 28, 2007 My GT4088R housing is 0.68 and it pulls to the redline very strongly (it is a unit modified by Precision though and I do have 264's) Quote Link to comment Share on other sites More sharing options...
Mike B Posted July 28, 2007 Share Posted July 28, 2007 My GT4088R housing is 0.68 and it pulls to the redline very strongly (it is a unit modified by Precision though and I do have 264's) sounds good... is it divided? my 35 (uses a precision housing too) ran out of puff around 6 on a .68 housing, and I run 264 cams as well. Maybe this is the key; bigger turbo, smaller ar.? maybe we need to meet up so we can check it out!? it would be interesting to see how the two cars compare.. Mine starts to tail off around 6200rpm, but I still have the stock jspec cams in! It's still 'pulling' though, but you can feel it dropping. yup, just what i had on the 35. intersting to see that Javansio's pulls to the line... Quote Link to comment Share on other sites More sharing options...
Homer Posted July 28, 2007 Share Posted July 28, 2007 yup, just what i had on the 35. intersting to see that Javansio's pulls to the line... From what I can find so far it's down to the cams rather than the turbo. Ryan was finding this during the mapping too. The US guys say the turbo should be pulling until 7k rpm, so thats more than enough for a street car. Will be interested to see Jays results too. The BL ones are put together by precision too, I wonder who actually makes them? Shame us guys aren't closer geographically, would be a good excuse for a meet Quote Link to comment Share on other sites More sharing options...
jevansio Posted July 29, 2007 Share Posted July 29, 2007 sounds good... is it divided? my 35 (uses a precision housing too) ran out of puff around 6 on a .68 housing, and I run 264 cams as well. Maybe this is the key; bigger turbo, smaller ar.? maybe we need to meet up so we can check it out!? it would be interesting to see how the two cars compare.. yup, just what i had on the 35. intersting to see that Javansio's pulls to the line... It's not divided Mike, aye we'll def have to meet up, should get the car back this week & mapped on Friday so can sort something out very soon. When I first got the car back after the rebuild & I was running it in it was so hard not to go past 6.5k, it just kept pulling & pulling well past that, I had to keep an eye on the revs all the time as if you changed gear when it felt natural you'd be past 7k Quote Link to comment Share on other sites More sharing options...
Inferno Posted July 29, 2007 Share Posted July 29, 2007 The AR's are quite different on the 2 turbos, that may explain the big difference in throttle response. My GT35R is .82 AR and as you describe throttle response is virtually instant. Hey Nic, How do you think a GT35R with an 0.63 A/R would compare to yours? I am thinking of going with one of these babies as I feel it will give me more then enough power for the time being, and even better response than the other 61mm turbos with larger A/R's.... also I think my 550cc injectors would work quite nicely in addition with my EMU and I might only need a fuel pump upgrade (and the other obligatory parts - intake, header/manifold???, dump pipe, bov, wastegate). Quote Link to comment Share on other sites More sharing options...
jevansio Posted July 29, 2007 Share Posted July 29, 2007 From what I can find so far it's down to the cams rather than the turbo. Ryan was finding this during the mapping too. The US guys say the turbo should be pulling until 7k rpm, so thats more than enough for a street car. Will be interested to see Jays results too. The BL ones are put together by precision too, I wonder who actually makes them? Shame us guys aren't closer geographically, would be a good excuse for a meet I know Daryl, it'd be great to have the side by side to see how they all go on the road. I'd of loved to go to the RR day too but Surrey is such a distance I hope when I say mine doesn't drop off past 6k that it's not in my imagination , I had a look at my last graph (1.25 BAR) and it shows power is on the up & torque isn't really taking a dive just yet as 7k nears: Quote Link to comment Share on other sites More sharing options...
Nic Posted July 29, 2007 Share Posted July 29, 2007 Hey Nic, How do you think a GT35R with an 0.63 A/R would compare to yours? I am thinking of going with one of these babies as I feel it will give me more then enough power for the time being, and even better response than the other 61mm turbos with larger A/R's.... also I think my 550cc injectors would work quite nicely in addition with my EMU and I might only need a fuel pump upgrade (and the other obligatory parts - intake, header/manifold???, dump pipe, bov, wastegate). The .63 AR should have a little more response and less top end. My GT35R with .82 AR though has virtually instant power, with very little lag; positive boost around 2K rpm and peak boost at 3Krpm and will spin the wheels when accelerating in first 3 gears. I can't imagine wanting any faster response than I already have. 550cc injectors will be close to their limit, I personally use 680cc injectors on mine. If you're still using the stock rail then Power Enterprise do drop in 650cc injectors that will fit. Quote Link to comment Share on other sites More sharing options...
Mike B Posted July 29, 2007 Share Posted July 29, 2007 I hope when I say mine doesn't drop off past 6k that it's not in my imagination , I had a look at my last graph (1.25 BAR) and it shows power is on the up & torque isn't really taking a dive just yet as 7k nears: can't argue with that... that's a lovely power curve there. I'd be really interested to see how yours goes. I may be sending my tubby of to get a smaller housing. Quote Link to comment Share on other sites More sharing options...
Wez Posted July 29, 2007 Share Posted July 29, 2007 Interesting information here guys, its good to see how the different spec turbos are changing spool charateristics. FYI The BL T67 is available with DBB and Journal Bearing with these options :- ar: .58, .68, .81 and .96 cover: E, H and S I have no idea how the various covers affect anything but from information gathered here I would say a .68 or .81 would prob be the best option. Quote Link to comment Share on other sites More sharing options...
dandan Posted July 29, 2007 Share Posted July 29, 2007 What are the compressor cover options and who has which one on here? Homer, Ian, SimonB? Quote Link to comment Share on other sites More sharing options...
Marty Posted July 29, 2007 Share Posted July 29, 2007 This is the graph off my dyno run, im running a sound performance T67. The car made 480rwhp at only 1.1bar. Very nice turbo to drive with, i have cams on mine so i dont feel the power dropping off one bit , even though the graph does show a slight dip over 6000rpm, its not noticeable. Not sure of the AR on the housing on mine, i'll have a look in a bit. Quote Link to comment Share on other sites More sharing options...
Wez Posted July 29, 2007 Share Posted July 29, 2007 I wonder if anyone has a dyno plot from a BL T63 turbo as this should sit in the middle of a T67 and T61, could be a nice compromise. You can see on my dyno that stock j-sepc cams and a small PHR Stage 1 are choking the motor in the higher rev range. Quote Link to comment Share on other sites More sharing options...
Jake Posted July 29, 2007 Author Share Posted July 29, 2007 the GT488R smallest housing available is a .96... they used to do a .85 non divided housing which Jamie P used, his replacement tubby came with a .96 I believe so it would be interesting to say what he thinks I think you're confusing the gt4088R with the non-R journal bearing turbo there Mike. I'm pretty sure Jamie has never had a 4088R, both his were plain 4088s. You can't really make comparisons between the housings of the two types because so much is different between them. so I have jumped from .68 housing to a .96.. maybe that explains a lot? I'm wondering if your ECU needs remapping for the new turbo. I know you said it's self-mapping but how well is it managing the ignition timing really? Can the V Pro really remap itself for a different turbo? It just seems unlikely to me, but I'm no expert. You can see on my dyno that stock j-sepc cams and a small PHR Stage 1 are choking the motor in the higher rev range. I don't believe the stock cams are a problem with the PHR1 turbo as it ran out power just the same on my car, which has 264/264 cams. Quote Link to comment Share on other sites More sharing options...
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