Dale FZ1

Re-checking that thread it looks like the owner misread the query and its actually a GTX3071. Makes much more sense how it might hit the numbers recorded. I didn't look closely enough at the overlay, and yep you were right, that unit made more everywhere. Pity the GT2871 was not ramped from the same rpm but the picture is there to see. While that graph depicts only what the thing can do in a loaded state (ie not transient), it's telling a story. I will remain circumspect regarding these GTX compressor units. Looking over the comp map, it is clear that the main advantage over the GT-RS 71mm 52T is that it doesn't fall away quite as much at PR>2.25. But the rotor speeds are much higher to pump the mass. But they both do roughly the same max mass flow, say 45lb/min. Observation only. Shame that guy got his model numbers mixed up. Either way, yes it's an interesting unit, and no I don't think GTX3067 is best suited to an RB25.

He's nominated a 0.73 housing - wonder what that is. I'm cautious about accepting the numbers quoted - 460rwhp @20psi when the performance map indicates the thing will do 45lb/min 2.5PR doesn't quite stack up. But the improvement from a better flowing/more efficient turbine is there for all to see when it was making almost the same power number (would like to see the torque curves overlaid actually for area under the curve) from 11psi vs the 2871 on 20psi. Notice that the GT28 comes on-song nicer down low - predictable. On an SR this could be a decent setup, not so sure on the larger capacity RB25.

Any ideas on manifold/gate setup you intend to use? Be sure to post up some pics of the setup and at least link your results into this thread so we get some continuity and a bit of direct comparison to what Disco's setup does.

Performance map for the GTX67mm suggests it is spec'd for high boost (>2bar) applications. Interestingly I see the current Garrett catalogue also shows a GTX2860 (rally), complete with marked choke point on its map for a 34mm restrictor. Again, specs show good flow capacity at very high PR. Seems like a bit of targeted marketing. With a bit more info at hand I'm confident Disco's existing spec will probably be the best for his aims. Given the 0.82 housing is also in the parts inventory, the pragmatic view would be to give it a run. I didn't think that the "feel" was much different, just that the 0.63 shifted the curve to the left so it all happened sooner (and tapered off sooner).

I’d consider the set performance parameters GT30 turbine ~300kW output best transient response, GT-RS as a benchmark max torque at lowest rpm The 0.63 housing is a compromise in itself, depending on hardware and fuelling choices. The two blokes I know that have used the 0.63 option on a GT30 both went with internal gates. Both experienced boost control issues in that they could not successfully run boost levels under 18-19psi. That to me says there are issues in bypassing sufficient gas via the gate to control turbo speed. Maybe no issue if the target output is 300kW because that’s the sort of boost required to hit that mark. I feel it’s about balancing things, because if the easiest gas path through the turbine assembly is via the turbine exducer then the gate is under-engineered and a potential problem. Best option to deal with that is via a reasonably engineered and large capacity external gate that gives the boost control Lithium suggests. A 1.4 bar mid range tapering to 1 bar @ 6500 would certainly give a huge shove in the 3-5000rpm range, if a little flat in comparison above there. With good (and effectively tuneable) boost control he could play and get what best suits his preferences. Disco’s thread on the TR30 unearthed a few photos of manifold/gate/turbo setups that I think have relevance to this GT30 unit and performance targets. The TR30 runs smaller exducer dimensions (smaller trim size) so the venting capabilities via the gate are addressed properly by good design engineering. I think it’s not hard to connect the dots here, and use the experiences gained in a pretty hard-core environment. As the 0.63 housing provides an increasing obstruction to gas flow as rpm and boost (mass flow) increases, the potential for reduced scavenging and heat retention also give cause for concern about reduced knock threshold for the engine at those high rpm. I agree that Disco’s use of ethanol blend fuel will provide resistance to knock not reliably available via pump 98. The GTX67mm compressor would certainly be an interesting oddity that would be difficult to predict until flow maps and dimensions are known, and even looking at how the rotor looks in comparison to the GT76mm and the GTX71mm. My thoughts would be that it would be more of the same as the GTX71. Higher rotor speeds before the thing pumps decent air mass, and a small but detectable difference in where/how it responds to a whiff of throttle on steady inclines. I don’t see the GTX67 as offering any likely practical benefit, so the existing 52T GT3076 would get the nod. The fact that Adrian already owns that unit says it would involve a dive into the unknown, with a cost associated. The slightly reduced throat size and flow potential of that unit (compared to the 56T GT3076 or the GTX3071) won’t prove to be detrimental, and I reckon this compressor spec will do close to “best match” for his performance targets and operation characteristics. All the above is just an opinion, but standing in Disco’s shoes that is the direction I would go.

Yes, straight fitment.

Trawling around I found a bit of info regarding the Mazda MZR-R, as developed by AER. I understand that AER was the an offshoot from Cosworth following their sale and corporate split-up, and this company does a lot of contract development work specifically for race/competition engines. I was already aware of a lot of speed gear available through the UK to suit the Mazda MZR, reference typically being made to Cosworth as the supplier. That production engine is what we see in things like the MX5, CX5, Ford Focus, and Falcon Ecoboost 4 cylinder. There is some pretty serious internal gear that is used in the MZR so we see them installed in 2.3 litre N/A form into Mark 2 Escorts, as a modern and cheaper equivalent of the 70s original BDA Cosworth. Seems that Mazda have been involved with this project engine powering LMP sports cars, and reference is made to the use of the TR30 in restrictor equipped form. Check http://www.racecar-engineering.com/articles/technology/mazda-mzr-r-lmp2/ and http://www.aerltd.com/products.html Pics of that engine in its proper environment, TR30 installed. One significant design outcome is very light weight of the TR30. I saw a claim of 8 pounds.

Poking around, I found these two pics. One is of the WRC Ford Zetec (restricted, 2.5 bar), the other is Ken Block's Ford Fiesta(unrestricted, 4 bar). The detail is quite amazing when you go through them. I think there was a link somewhere indicating a Mazda LMP was running a TR30 but no pics found. There is also a Garrett spec sheet/blurb posted up here http://www.freshalloy.com/showthread.php/153372-Tial-vs-Twinscroll/page2 that makes for interesting reading too. They state explicitly that a couple of their compressor specs are for restrictor type classes. Makes Lithium's dyno sheets and comments about that Evo hold pretty true. Adrian there will always be a reason to want something different than the next man. Mick's R33 would be difficult to improve upon for a very streetable and innocuous road car perspective. It's quiet, and it hammers in a refined way. It's that much fun I would challenge anyone to not laugh aloud during/after a drive. Some day I look to repaying the favour to him. Given you have the hardware available, I would think that a bit of a run with Mick would see your 52T GT3076 fitted up and the car tuned for ethanol. I wouldn't be holding my breath for massive improvements in transients from that spec and the GTX3067. Noticeable, yes, but only slight. Consult with Wolverine if necessary regarding what happens when the turbine spec is unchanged and comp is altered from 82 to 76mm. .Your Vipec can handle any changes necessary with a turbo upgrade, and the pump is easy - just be sure to get a direct full-voltage feed. Be good to see a bit of info regarding the EFR gear flowing into this thread too.

After a few rounds of views being exchanged, it seems everyone agrees this rare item is for competition use only. And it's going to be a tough thing. Don't know who would care to run their RB25 with 3 bar boost, maybe it could be effective in IPRA category where restrictors are part of the deal. Wish lists are great but it wouldn't be a good idea to hold your breath waiting to see the TR30 turbine in production this decade at least. Honeywell are probably happy that there are threads like this in existence since it keeps the Garrett name bubbling upwards in consumer's minds. I think the best outcome is that enthusiasts learn what they can about what is effectively a development prototype and see how that fits with commercially available units. Then pick the option that best suits your needs. The only way I could suggest low rpm transient response and higher rpm torque is achieveable is to go along the lines of a Lancia Delta S4 (supercharged + turbocharged), or accept a degree of compromise. I know of nobody who has argued Mick-o did not achieve a very strong and driveable result. 450rwhp might exceed Adrian's requirements but I would suggest accepting a trial would help to make any person decide what they like or what they need. Still waiting to see what pics emerge from the motorsport world regarding fitment of these TR30 things too.

This thread is a bit of an interesting oddity, would be good to hear from Stao regarding the trim sizes and maybe what Kamak do have available to trial. I'd also like to see it keep on-track, and maybe pics of other machines that run the TR30.

I'll stand corrected, but believe that in the transition from Group B to Group A rally, restrictors were mandated at an early stage to limit hp production to ~300 @ crank. FIA have then since played with the actual size, from 40-32mm depending on category and the comp series. Circuit racing Group A cars were not restrained in the same way. Without a mandated max boost pressure for the rally machines, and anti-lag permissible they were able to push 2 bar (so 3 bar absolute) into the engine and make the massive, low-mid range torque that slingshots them out of corners. Restrictors make the torque fall over very quickly, and current restrictor-equipped cars typically use 5000rpm as a change point, making them sound like a John Deere tractor while they blast past. So I can see a lot of sense in spec'ing those compressors according to rule driven restrictors, and also the turbines according to drive requirements - hence the rally-spec 73 trim rotor. Both the 71mm and 76mm comp maps do appear very similar to what is published for the GT3071R and GT3076R, in shape at least. On-thread, the TR30 turbine is an interesting piece of gear, both from the housing used, and also the design features. Drop the blade count increases high-speed efficiency and flow but at the cost of response. Build it from ultra light material, and regain some of the lower end response via reduced inertia. Also shape the blades according to current knowledge/experience to make the best use of the gas flow. All of that I like. Disco's advocacy of reduced trim sizes contributing to response, and comments from Lithium in another thread drove me to check out a few things regarding production items available from other manufacturers, focus on MHI and the Kinugawa copies. What an interesting find: TD06H, broadly similar dimensions to the GT35 turbine is a 77T and available in 12, 11, and 9 blades. Inconel is the metal used, not titanium. Blade shape looks very similar to the Garrett design also, maybe a little more open in the exducer area. TD06SL2 has broadly similar dimensions to the GT30 turbine, 79T and available in 12 and 11 blade options. I'm sure a bit of fishing around would (maybe) yield availability of either a 9 blader or titanium options, given that was the extent things went to with the Evo TDO5H. Neither of those components are comparable to a high cost, competition only prototype but it is interesting to see what design features other manufacturers are making available to the public, and perhaps what sort of home-brew developments can be bought at affordable prices. It would be good to see some detailed pictures linked into this thread, maybe including some of the BW EFR gear so we can try to gauge the variety of ideas being implemented into current, (relatively) up-to-date turbine technology vs the low volume racing prototypes.

Looking at the performance maps, and some of the dimensions, this range appears (to me at least) to be 100% designed for racing within rules. Mention of defined turbine exducer diameters, rally spec turbines, and compressors with inducers not much larger than rule-mandated intake restrictors all point the way to engineering gear that can do the business with high PR efficiency but not necessarily (spec dependent) flow great amounts in absolute terms. Both the WRC engines and LMP diesels run very high boost but within their own design parameters are not intended/able to exceed certain hp due to inlet restrictions. Blade shape, blade count, and hub sizes also no doubt contribute to the performance characteristics, but I wouldn't think they are likely to be the type/spec of unit you would use anytime soon on a mild/responsive road application. I'd think the use of smaller trim turbine might give the transient response you've made comment about, but given the obvious restriction to exhaust flow through the turbine itself, design focus on flow efficiency through the wastegate system would become more important. The use of round turbine inlet is a good thing, don't really get why Garrett persist with the rectangular flange and flow paths with angular edges on regular production items. MHI are onto it, and the engine manufacturers generally use circular cross sections in their head port shapes. "Because they've always done it that way" doesn't cut it for me when the rest of the engineering/design world has moved on. The asking price of $3500 per unit is high but not exorbitant and it would be interesting to see someone with the budget and drive to acquire and fit one just for kicks. Wonder how you'd go for spares or an overhaul kit? Good find.

I seem to recall the 2871 range going 390hp, 420hp, 450hp for the 48T, 52T, 56T. Most of Garrett's ratings seem to factor use of the biggest A/R turbine

The TD06SH + 12cm should offer a fair bit more turbine flow than the SL2 + 10cm found on the T67 25G. I think that the SH will be enough to handle all the flow a 25G can throw at it so maybe pointless going for bigger turbine unless you're looking at capacity bigger than 3 litre. I can't find hard evidence on the TDO7 specs but it seems likely to offer nothing other than a 0.5mm bigger shaft. I'd say run the SH and see how it performs.

+1 Regardless of whether you're running a 52 or 56T, this combination is one of the best matches around for a RB25. Ethanol is only going to make it better. If you really want the transient response and lower rpm urge that the GTRS gives, you're basically going to need a RB30 bottom end.

Kando have had a few oddball (unexpected) units on offer, including the Hino (truck) spec GT3576 (plain bearing, split pulse IW turbine). Not surprised to see that GT3071. Likewise the TD06 hybrid with TO4R compressor, it's been around as have other hybrids with the old-school 60-1 compressor. Maybe not the most efficient stuff but they can work reasonably well at the price. Re the TD07 unit, I think the main thing that will differentiate them from the TDO6 based units is the size of the centre section, bigger diameter shaft, and no water cooling option. Take a cue from the T67-25G.

Twin injectors per runner was used in the YB Cosworth Sierra RS500, although the second rail was inactive for road/emissions. The old 2 litre Supertourer Audi A4 also used twin injectors. Prior to easily flashable ECUs, it was relatively common to see overall enrichment via a potentiometer on the coolant sensor. Made the ECU think it was still in warm-up mode and push more fuel in.

My 30DET produces torque much the same way - peak torque from 3400-6900 in a wide dead-flat plateau. It makes for an incredibly easy drive, as for track work it is never really out of its "best" zone. Reviewing data it seemed to matter very litle whether some technical sections were run in either 3rd or 4th gear - point to point there was little variation in time. With that style of delivery there does not seem to be that "rush" generally associated with some turbocharged engines, and traction relatively easy to find, even running 225/50 semi slicks and knocking out a conservative 415rwhp. I get Brad's approach, although it might not be for everyone's preference.

I think yours will be the third R35 on the coast. Hopefully ownership will be a satisfying experience.

Be interesting to know if the core design is exactly the same ie. shape/type of turbulators (if any) and the fins/inch count between the PWR and the copper unit.

Cams and inlet manifold change not necessary at the targeted output. This has been discussed frequently on this forum. Divert the funds into the necessary ECU and decent tuning.

It seems that the benefit of billet compressor design is in improved efficiency at higher PR, not in dramatically reduced boost response times. Still be interesting to try them back to back if only to see whether response and power delivery is any more/less progressive. I'd say unless you are planning on running 20+psi stick with the std comp wheel. For my money I would be asking about the thrust bearing - seem to recall spotting a "race" upgrade to 360 degree version in the Kamak catalogue.

Under what conditions? Presuming road use.

And is there any sign of the surge you reported with the other setup?

Consider whether the cam spec has excessive overlap and not suitable for forced induction? Exhaust valve opening way early could cause hot gases to blow out through the turbine leading to high EGT and not hitting the potential power output. Running an adjustable cam gear won't alter the phasing between inlet and exhaust, so the overall valve timing is either advanced or retarded, but the relationship between valve events does not change. Try another cam grind altogether, but only after you spend the time/effort by checking cam timing against the card that presumably was supplied by Camtech.. If your brother won't play ball, then close the garage door and let him to it while you do your thing.