malibud Posted September 11, 2014 Share Posted September 11, 2014 Below is the turbo that came on my car. This my first turbo car other than diesel truck so I really don't have anything to compare it to. I have a carbed 240 w/l28 on the line they are about the same. The car, 240z has a modified 300zx ecu, 420 injectors, external wastegate, forged pistons... The build sheet says good for up to 20lbs of boost but without a wide band I have it set at 12. My question, it seems to take a while to spool. 1st gear little or no boost 2nd getting some .. 3rd 3000rpm hits boost takes off 4th the same as 3rd nice. 5th lots of fun but cant really drive too much at 100plus mph. So.. is the turbo too big ? will a smaller turbo spool quicker? I thought i fixed the boost leaks but i need to check again. dont have $ for turbo right now but maybe in near future... I am not sure of the cam thats in it n42 head that has had some work not sure what but it came with a brand new cam that I have sitting in a box : 109degrees LC ? Int exh Dur. 280 270 lift 480 480 clear 006 010 open 31 64 close 59 26 I have done some searching but nothing to tell if the cam will add more bottom end >... Any thoughts are appreciated Thanks Dan Garrett GT3076R Turbocharger Ball bearing Oil & Water-cooled bearing system Upgrade turbocharger for GT3071R non-wastegated ball-bearing turbocharger; turbine housing flanges are outline interchangeable T3 turbine inlet flange Ideal for medium displacement engines making up to 525 hp Turbine housing kit options available Compressor Specifications: 56 trim compressor wheel 0.60 AR compressor housing Turbine Specifications: 84 trim turbine wheel 1.06, 0.82 & 0.63 AR turbine housings available Quote Link to comment Share on other sites More sharing options...
roger280zx Posted September 11, 2014 Share Posted September 11, 2014 Get a wide band!!! After that tune timing and fuel, this can greatly reduce spool time. Inlet/ exhaust restrictions hinder spool and breathing all around. What gear are you running? What turbine housing are you running? The 3076 is well documented here and there are many who don't like it for the characteristics you described above. IMO it is better suited for small displacement/ higher boost applications. Quote Link to comment Share on other sites More sharing options...
malibud Posted September 12, 2014 Author Share Posted September 12, 2014 (edited) I am saving for innovative wideband ,boost controller/gauge in one . It is suppose to be able to let you set values to cut boost when lean. I am running a remapped 300zx ecu so I can only adjust fuel by pressure . Most of what I read was people using it on a RB not too many on a L28. Spool time is what I have read is the common complaint with this turbo. I will have to look at the turbine housing . The rear end is a lsd from 300turbo so 3.7 ? I need to clean up the intercooler and check for leaks.ThanksDc Edited September 12, 2014 by malibud Quote Link to comment Share on other sites More sharing options...
Tony D Posted September 15, 2014 Share Posted September 15, 2014 Which AR Turbine Housing do you have? 1.06? Try the 0.63... Most people get carried away and use the AR that is way too big, JeffP can get 17psi at 3,200 on his GT35R.... But he's not running a 1.06 AR Housing, he was loath that he couldn't stay with the 0.63 and ended up using the 0.82. Quote Link to comment Share on other sites More sharing options...
malibud Posted September 16, 2014 Author Share Posted September 16, 2014 I have looked on the turbine housing can't find the a/r housing . The garrett sales guy said its stamped on the inside ? Does not make sense but he said I would have to remove the turbo to get the A/R size . Said it may be stamped on outside I I did not see it . Any ideas ? DC Quote Link to comment Share on other sites More sharing options...
Tony D Posted September 16, 2014 Share Posted September 16, 2014 You don't have a sales invoice that gives the specs of THAT turbo, and not a general cut-sheet of the whole range? The turbo supplier should have been able to tell you what they sold you. How can you apply a turbo if you don't know what specifications it has? Big Mistake. Quote Link to comment Share on other sites More sharing options...
malibud Posted September 16, 2014 Author Share Posted September 16, 2014 I bought the car as is . The PO or someone else put it on . I have some of the build sheet but no mention of the turbo .. Quote Link to comment Share on other sites More sharing options...
Tony D Posted September 16, 2014 Share Posted September 16, 2014 Looks like you're pulling a turbo, and likely asking to buy a 0.63 A/R housing from somewhere... Quote Link to comment Share on other sites More sharing options...
roger280zx Posted September 19, 2014 Share Posted September 19, 2014 I really liked how my old turbo drove in its previous, limited state of tune. I pulled it to measure wheels, clean, exc. learning that it was wrong for my application. You have to know what you have before you can move forward. Quote Link to comment Share on other sites More sharing options...
malibud Posted September 19, 2014 Author Share Posted September 19, 2014 Looks like I will have to pull it out. Quote Link to comment Share on other sites More sharing options...
Tony D Posted September 19, 2014 Share Posted September 19, 2014 At least to find out the A/R, for sure. It should be good with a 0.63, even an 0.82... but that 1.06 will suck donkey testes in terms of getting spool in any gear but when you got loads of load on it! Quote Link to comment Share on other sites More sharing options...
malibud Posted September 19, 2014 Author Share Posted September 19, 2014 So from what I have read a turbo cam install would not help much. Is there any way I can figure out whats in there ? n47 head some porting . Quote Link to comment Share on other sites More sharing options...
Tony D Posted September 21, 2014 Share Posted September 21, 2014 (edited) So from what I have read a turbo cam install would not help much. Is there any way I can figure out whats in there ? n47 head some porting . Huh? The issue is in your turbo. Pull the turbo and find out what it is and then get the right housing to match the displacement and rest of the build. The boost you SHOULD get is 20psi in 1st gear at 3,000 rpms or below. The ONLY thing in your list of parts that will cause what you are describing is a misapplied turbo hot side A/R that is far too large. I'll say it again: I bet money you got some B.S. 1.06 A/R as some racerboy thought they needed the big A/R 'for all the flow through the engine' and all they did was ABSOLUTELY kill the proper response from the turbo. My bet, a 0.63 A/R will get you full boost in 1st gear at 2500-3,000 rpms. The External WG will likely control any creep issues at 7,000 just fine. Fix the hot side A/R, nothing internal to the engine except for a 175 shot of NOS is going to pick up your bottom end. Edited September 21, 2014 by Tony D Quote Link to comment Share on other sites More sharing options...
malibud Posted October 3, 2014 Author Share Posted October 3, 2014 Got it Tony, I talked with another member Hoke240z who is going to help down the road. One thing I forgot to mention which he though might effect boost was the wastegate is attached to a long flexible pipe it dumps out at the front of the engine block. the pipe is a bout 2 foot long. The new plan is to take it all apart. Check the AR on the turbo. weld the Wastegate close to the manifold and have it dump back in the the exhaust . It will be a fall/winter project let you know how it goes.. Thanks Quote Link to comment Share on other sites More sharing options...
Tony D Posted October 3, 2014 Share Posted October 3, 2014 2' of 1 5/8" tubing will fill to pressure almost instantly. If anything that will be minimally noticed on spool, but result in boost control lag on boost, or possibly slight excursions into over boost. You can fix it to be more responsive... But that A/R... Quote Link to comment Share on other sites More sharing options...
malibud Posted November 30, 2014 Author Share Posted November 30, 2014 Update: Pulled the turbo and YES Tony you were right 1.06 AR turbine housing guess I am ordering a .63 unless there are any other better options.From what I have read .83 is still too big for autocross and having fun in 2-3rd gear. I plan to run around 12 -15lbs of boost maybe turn it up a bit here and there. Primarily wanting more bottom end..... Oya and I did install a wideband about 12-14 at idle dropping steadily under boost to about 8-9a/r a little rich ? Thanks again for all the info/help DC Quote Link to comment Share on other sites More sharing options...
Pac_Man Posted November 30, 2014 Share Posted November 30, 2014 8-9 AFR sounds pretty rich although it may be a necessity to prevent detonation from occurring at your boost levels with an ECU that has limited tuning capacity. A .83 housing would help but if you want to autocross the car it sounds like .63 would be ideal for you. I want to say that's what the stock T3 was on the L28ETs. Quote Link to comment Share on other sites More sharing options...
Tony D Posted December 1, 2014 Share Posted December 1, 2014 (edited) Way rich, as in puke black smoke out the tailpipe. 0.63 should give you boost at 3,000 or before in any gear. The 0.83 will be higher, over 3,000 but well before 4,000. It's a nice A/R for sustained high speed driving in places like West Texas where you can cruise in vacuum at 75-80 mph and hammer it to pass with instant boost. With the 0.63 in my car at that speed it was "zero" manifold vacuum and any sort of throttle application put my into 3psi of boost...manageable, but not the greatest for fuel economy. The 0.48 I had was on the wastegate at those speeds, in an AutoX it was making full boost at 1,700 and I would short shift to second to let the torque pull me. You need 11-12:1 AFR up to around torque peak...then you need to pull fuel like crazy. The final runs on the S130 were near 12.8:1 AFR at 7,200 at 17psi making over 600hp on a GT35. The GT30 will obviously be lower flow, but you get the idea. Edited December 1, 2014 by Tony D Quote Link to comment Share on other sites More sharing options...
Tony D Posted December 1, 2014 Share Posted December 1, 2014 And don't forget...these always that cheater shot of NOS to aid spool! LOL Quote Link to comment Share on other sites More sharing options...
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