My XR, pretty much the next version of the HTA3076, spools like a 3071. No problem hitting 20 psi by 3400 starting at 3k.
I wish I'd be able to participate. I have a HTA3576 but I have a higher CR as well so it'd be too apples to oranges.
Maybe the reason they spool fast is comparatively smaller hotsides, like was referred to in the vid? That would definitely give a spool advantage, at the expense of some top-end.
You can jump in with that, if you want. Originally, I created this thread when talking about the elusive "safe" upper whp limit. We all hear about the "safe" upper wtq limit of ~380 or so, but the whp limit is much less commonly discussed in detail. @Realgib3 raised some very good points. Bigger turbos lend to being safe even closer to 500whp because of how/where they make power, that they don't have to be pushed as hard (so much cooler), and that tons of alky gives you a safety threshold. Though it wasn't specifically mentioned, everything else being equal, a turbo with a larger hotside (i.e., 3076/5858 and above, like he mentioned) won't "bottleneck" the heat in the CC nearly as much, AFAIK. So that's a more specific way of saying what he already essentially said.
Metallurgy and other science FTW! I'm currently working on the master equation that takes every single variable into account to let you know exactly when your engine will fail (down to the tenth of a mile), and by what cause. It's a work in progress....
Yeah, it may take several lifetimes if I'm unaided. It's like the String Theory of engine failure
Unfortunately, I'm on a locked FREEKTUNE map. When I first went S3, I was fully confident in my ability to self-tune it great, but I chose instead to go pro because at the time Justin was still not locking maps. As a student of tuning, I saw it essentially as 1) paying to have a pro-quality tune, 2) paying to essentially have tune tutoring, watching everything he did revision by revision to learn further/refine my craft more. I was very inspired many times in that he did exactly what I would've; other times, he'd do something so elegant/simple that I was amazed by his skill. Anyways, all of that to say that I could get further refinements for 1st and 2nd, but it'd be a re-tune. BTW, I totally agree with you about loving the "gutsy" feel of the S3. That's why I covet the EFR7163 if/when I finally go 500whp: it's the rarest type of turbo - one with that gutsy low-end, but still can support ~550 or so.
Well, electrical engineers in our community, this looks like an awesome project!
With most larger turbos, it's a self-resolving issue due to the nature of their boost threshold and spooling time. But with next-level turbos, like the EFR7163, it'll still be an issue. That's why I'd really LOVE to have 4-port ability. I'm also curious about the EBCS system that already comes on the EFR7163 and how low the boost can be set, especially in 1st and 2nd.
On my 6758 it took about 40% WGDC to see ~1-2 PSI gain; the curve got aggressive after that with 100% peaking at about 20-22 depending on weather.
Definitely. Either that, or I should throw an AWD conversion on the to-do list when going built/EFR7163
Pretty sure that 750 figure is only for the GTX3576r. The 30-frame series doesn't have a big enough hotside, apparently. The rule of thumb is a turbo's horsepower support level is lbs/min x 10. But if you look at the GTX3076r compressor map on this gen 2 version, it only flows ~67 lbs/min. Oddly enough, the compressor map for the GTX3576r looks pretty much identical. Anyways, that's a far cry from a 750hp turbo:
Indeed, but that's an excellent recipe for shortened turbo life. And if I'm going to drop a few grand on the turbo alone, best believe I'm going to stay in the islands, LOL.
This is a game-changer. I'm surprised I never knew about this. Email out to Justin asking his pro opinion/if he'd be able to implement with a re-tune fee.
I just found this forum so I'm going to revive this to share my knowledge on prevention of this from self tuning over the years.
