thehelix112

Well thats the high side of 200 so wind is providing quite enough load. Still pulling at close to 0.3g according to my datalog calculations though. Dave

Just worked it out. GT35R turbine wheel trim: 84 (2.68^2/2.45^2)*100 T3 Stage V turbine wheel trim: 76 (2.798^2/2.439^2)*100 Was it a T3 turbine wheel you were testing? I assume so because the T4 turbine wheels are measured in letter trims? N...Q I think? I'll be surprised if they behave the same. Dave

Except of course, that a GT35R does not run a stage V exhaust turbine I don't think. Thus the wheel itself, while you are correct in saying it is the same exducer diameter, makes better use of whatever air it is being fed, and will increase exhaust backpressure over the stage V turbine wheel for a given A/R. I think. Unsure of the `stage' spec of a GT35R wheel. Dave

Data log function and a hill. Works a treat. Need some long arse hills for 4th gear runs though. Dave

To be fair, the GT30 0.63 is going to be smaller than the GT35 0.63. And also the internally gated XR6T 1.06 housing isn't going to flow as well as the GT35R 1.06 housing. The 0.5 front won't make any difference to how the turbo spools, its only the wheels' inertia and turbine housing that do it. Dave

Looking good!. This is for a forced induction application I presume? Will be very interested to see your plenum design. Dave

I don't know why people still much about with T3/T4 (assuming they have money of course). Everything on a GTXXR is better, then ITS turbochargers are better again! Dave

Which GT28 exactly? http://www.turbobygarrett.com/turbobygarrett/products/turbochargers.html#medium As you can see, there are atleast 9 various BB combinations ranging from 250hp up to closer to 450hp. Dave

Ya. Small cam too. Makes max torque 4500 or so. Dave

Chris, Yes they are, but when you move the LCA outwards you are moving the steering arm outwards too (and the bottom of the strut), if you don't adjust the tie rod end outwards too then you end up with mega toe-in. Make sense? Dave

Twin turbos have theoretically better performance (over non-twin scroll single turbochargers), but you have to route twice as many oil feeds, oil returns, water feeds, water returns, air inlets, intercooler piping, dump pipes. Headfuckmuchness. Dave

All good. Dave

I'm struggling to see how the data from an old turbo (assuming its not a 0.63 GT35R) has any influence on the effect a GT35R turbo with that small a turbine housing will have. I'm not trying to have a go, I'm just curious. I'm also curious as to the 0.05" dur of your camshaft. Mine is just over stock at around 220 deg and I make max power around 6000 (I think). Advertised duration means jack ****. Can't wait to see your dyno graph of 0.63 GT35R @ 7000. Dave

Guys, I run out of thread on my steering tie rod ends when I try to wind in anywhere near decent track camber settings. Has anyone used spacers or other components to fix this problem? I want 3-4 degrees and am nowhere near it with the std rack/tie rod ends. Thanks, Dave

tannji, Being a devils advocate simply means asking questions, you've asked them. This is the answer. zguy36 is not saying STS systems don't work. He is simply stating quite correctly that heat increases pressure differential across a turbine, and there is less heat at the back of the exhaust (both of which didn't I see STS say themselves as quoted by someone in a previous thread?). Dave

TimZ, I tune to AFRs and detontation. Wind timing back to whatever doesn't ping, get AFRs right, then wind timing back in slowly until it pings, then back off a touch. Done. Sound reasonable? Dave

Jeff, I'm still not sure what you're talking about. Have you revved your car past 5000 with the GT35R 0.63 configuration? If so, is this http://www.angelfire.com/extreme/280zxt/images5/Graph1.jpg the dyno graph for it? Dave

You're running the 0.63 on a 3.0L, and you've never revved it above 5000 and you're telling us to get them? Are you SURE its not going to die over 7000rpm? I remain to be convinced I'm sorry. Edit: I suppose for a std engine the 0.63 would be great: wider power band as most L28s get max power around 5600 unless they've got some work/camming. I want more power than that, and later on so I'm happy to sacrifise some low down response. 3500-3700 is perfect for me, revs never drop anywhere near that on the track, and i can drive it off boost happy as larry. Depends what you want to use the car for I suppose. We'll have to compare dyno graphs (apples and oranges given you've got a stroker) but anyway. What cam are you running jeff? Dave

Are you comparing that with anti-lag on non-bb turbos? Apples with apples? Dave

They are small as hell T25s I believe. They're designed for excellent response being fed by 1.3L each. Will have boost very low being fed by 1.4L. Get steel wheels so you can wind them up a tad. Apparently good for close to 300rwkw with steel wheels. Good luck, Dave

587hp, 26psi, 6000rpm. Dave

Oh and fwiw I believe all Garret GTs have 360deg thrust bearings which are options on older turbos so they're really essentially the same? Dave

MatMan, You I think are talking about the thrust bearings? The garrett catalogue says the BB cartridges are 10 times more durable than the plain journal ones. That combined with the higher nickel content turbine housings.. no contest IMHO. Friend used to have his T4 go soft every 3 race meetings. 3 seasons on a GT35R and no change. Good enough for me. Dave

You two can stop anytime. FWIW, zguy36 is making a lot more sense to me. Dave

Fair enough. I'd prefer to have a fast car that may or may not shoot flames (who give a damn really) than a slow car that make people think it was fast when you drove it down the street. Dave