Jump to content
SAU Community

Recommended Posts

At the end of the day it just flows X amount of air through the compressor, how much of it the engine can't ingest gives you the boost figure. I couldn't run more than 23psi on the final tune with the GTX3071 with 1.06 rear, the compressor was way out of efficiency and it made less power from heating the air with no benefit.

I just slotted the GTX3076 with .82 rear in today so I will let you know the outcome Wednesday hopefully. I can already tell its much more responsive... :)

giddy up, will be watching for your results, one day mine will get tuned too to add to the GTX results. Just need a resonator and wait for a dyno to be available, they all booked out in brissy for winterinternationals and jamboree i think.

he first tuned it without E85 and made 288kw with a 0.82rear on about the same boost,

4300rpm to get 200kw so they are comparable , take 20kw off for the rear housing difference and its very close, take into account a slipping clutch was was noted, and they would be very close at that point.

so looks like the two are not far apart, and personally the sound of the 76 even in GTX form is awesome. :whistling:

Edited by SliverS2

I should be able to get an overlay of both graphs but I can feel the .82 is perfect, probably for either turbo, and as they have the same turbine, they should feel much the same on the road.

Mine with the stock airbox is still silent. :(

So you both will be running .82 ext. gates in the gtx3076? Interested to see the results.

Was mickos 98 tune with a low mount .82 internal gate? 200rwkw by 4300 is pretty responsive in my view. I know he was pumping a fair bit of boost, but that might have just been on e85.

a .63 housing on a gtx3076 is a little silly. you'd be much better off with a gtx3071 or a normal gt3076 as with the .63 you'll be limited to a fair bit less than the x76 compressor can flow.

still, not a bad graph considering. the advantage is when you want a little more you can simply bolt on a bigger housing and maybe a better manifold and make a fair bit more

You could try to up the gain on the boost controller and possibly end up with a slight boost spike. Looks like the boost is set to 18psi but doesn't quite control it near max torque (~45-5000rpm). I suspect the thing is VERY close to compressor surge while boosting and your getting some very slight symptoms from that. With a compressor bigger than a 76mm 56 trim and with a 0.63A/R it'd have to be close to surge.

You can't tell driveability or response from a dyno sheet. How does it FEEL coming onto boost? Does it actually make fast boost at 4000rpm? What are the mixtures like?

Edited by simpletool

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • The oil pressure sensor for logging, does it happen to be the one that was slowly breaking out of the oil block? If it is,I would be ignoring your logs. You had a leak at the sensor which would mean it can't read accurately. It's a small hole at the sensor, and you had a small hole just before it, meaning you could have lost significant pressure reading.   As for brakes, if it's just fluid getting old, you won't necessarily end up with air sitting in the line. Bleed a shit tonne of fluid through so you effectively replace it and go again. Oh and, pay close attention to the pressure gauge while on track!
    • I don't know it is due to that. It could just be due to load on track being more than a dyno. But it would be nice to rule it out. We're talking a fraction of a second of pulling ~1 degree of timing. So it's not a lot, but I'd rather it be 0... Thicker oil isn't really a "bandaid" if it's oil that is going to run at 125C, is it? It will be thicker at 100 and thus at 125, where the 40 weight may not be as thick as one may like for that use. I already have a big pump that has been ported. They (They in this instance being the guy that built my heads) port them so they flow more at lower RPM but have a bypass spring that I believe is ~70psi. I have seen 70psi of oil pressure up top in the past, before I knew I had this leak. I have a 25 row oil cooler that takes up all the space in the driver side guard. It is interesting that GM themselves recommend 0-30 oil for their Vette applications. Unless you take it to the track where the official word is to put 20-50w oil in there, then take that back out after your track day is done and return to 0-30.
    • Nice, looks great. Nice work getting the factory parts also. Never know when you'll need them.
    • Thanks @jtha7 I will have a look around tomorrow but it is a prick of a spot. These are some photos i tried taking 
    • I take it that the knock retard is from bearings tapping a little tune? Thicker oil is a fragile bandaid. You need a much bigger oil cooler and probably the bigger pump being discussed.
×
×
  • Create New...