Hypergear Turbochargers and High flow Services Development thread

[hy_rpm]

Ss1.5

[GTScotT]

Dyno didn't go the best today

On 20psi was making 250rwkw and power to limiter which was same power as before on 25psi but before power dropped off at 5600rpm now pulls to limiter

Yavuz said this turbo has more legs than the other turbo but as the boost was turned up detonation started to set in on 23psi was 263kw but slight pinging so left it at 20psi

I'm going to try the .86 rear on it in a few weeks and see how I go as he said the engine will be a lot happier with the .86rear on the higher boost pressure better

Hopefully doesn't hurt response too much but now it always starting to boost on any throttle

This is almost the same issue I had with mine. We got to 20psi but as we turned it up more it would ping straight away.

Ask Yavuz if the symptoms are the same as mine... Maybe its something in the design that Stao should be aware of.

[Dose Pipe Sutututu]

This is almost the same issue I had with mine. We got to 20psi but as we turned it up more it would ping straight away.

Ask Yavuz if the symptoms are the same as mine... Maybe its something in the design that Stao should be aware of.

sounds like too much exhaust back pressure, if you could externally gate this thing you would be able to add more boost (judging from the statements above)

[GTScotT]

The new owner of my turbo has it plumbed EWG, so we will see what result he whips out.

[hypergear]

Its on a .64 rear housing. I was on 255rwkws @ 20psi and only gained 15kws with 5psi of extra boost. Those turbines are good for the 250rwkws mark. Any thing large on the exhaust end would hurt response by a lot for the SR20det specially without VCT. Ideally they are best working on a variable turbine geometry. Still work in progress at current stage.

[GTScotT]

Or a noisy dirty gate

[hy_rpm]

Or a noisy dirty gate

If I reach 270rwkw I will be happy as now if he upped the boost he said he had to remove a lot of timing to the point that it made the same power up top with less boost and more timing

It was

So hopefully with the .86 rear the engine can breathe better and won't knock with 20+psi and the timing can be added back in

Was yours with the .64 rear aswell ?

[GTScotT]

Yeah mine was a .64

At the drags I bumped the knob on my EBC shifting to 3rd and got 23psi. It pinged really loud in 4th but went over 119mph lol (117mph @ 18psi real power roughly 238kw)

Get that issue resolved and there is a lot more power stowed away.

[hy_rpm]

Yeah with 250kw before with the atr28g2 trapped 120mph and 260kw with the td05h trapped 122mph

Hopefully the .86 fixes it

[hypergear]

Another option is run the ATR28G3 turbine wheel. This is also a customized turbine wheel that I've made to suit a T28x bearing housing originally for high flowing Stock T28. This CHRA isn't very popular on the CA/SRs how ever used often on the CT20 Supra twin high flows.

It appears to be 500RPMs laggier on paper when its first trailed in 2009. Now using FNT turbine and SS1.5 billet comp wheel I might be able to gain 300RPMs in response to what it was, using a .64 turbine getting 20psi by 4000RPMs while not chocking the SR20det motor in upper revs. Will update photos once its been made.

[hy_rpm]

Yeah but is it the turbine chocking the engine or turbine housing ?

As the turbine housing ar is the measurement of the turbine housing inlet so wouldn't that the first bottleneck for the engine ?

I'll still give the .86 a try on my car to see how it goes but are you going to try the atr28g3 turbine on the ss1.5 ? Also what size is it and you got your s14 engine fixed yet ?

[hypergear]

Unlikely to be chocking, just like high flowing a small R33 turbocharger using factory housing and get full potential of that. I just didn't like lag.

I've fixed the timing chain, and ordered a brand new VCT cam gear form US. Will be back on the dyno very soon.

[hy_rpm]

What is unlikely to be choking the turbine or housing ?

As you aren't running very high boost on most of the r33-34 highflows most around 15-20 psi max

[hy_rpm]

As can be seen in you 21u and op6 high flows there is a difference in power due to rear housing ar

Also are you using the same size wheels in both the op6 high flows and 21u ?

[hypergear]

OP6 and 21U run the same high flow profile. and makes about 30kws differences in power.

Run larger wheels also has a "bigger housing" affect. Means it enables the housing to discharge air faster, less back pressure, less heat. On the same time needs higher velocity to spool. Which is lag. Just like as if I can drop in a GT35 turbine in a .64 rear it will be making 300rwkws+.

[hy_rpm]

Ok I get you as the turbine wheel is bigger the bore for its much bigger and it needs more gas to turn it so less back pressure

If I get the 20-30kw gain I'll be happy as my injectors will be maxxed anyway thanks

[discopotato03]

From what I've read in the past the 76 trim GT28 turbine works alright in the matching 0.64 AR GT28 turbine housing but can have response issues in the larger 0.86 GT28 housing . When you team this up with a 2L four banger the "time to torque" gets annoying when you want grunt now .

IMO the turbine has to spin fast enough to run the compressor in its useful speed range and not create too much resistance to flow - with the engine in a boosted state .

Some claim that using the larger 0.86 housing slows the exhaust velocity too much and the turbine/compressor speed is less creating lag .

I had one on the old GT2860RS (FJ20) but these have relatively small 60mm OD compressors which didn't need much turbine power to spin up anyway . The theory here was low exhaust pressure when running in a supercharged state possibly maxing the small compressor but power out of these wasn't that high .

Now days similar or slightly larger diameter GTX etc billet compressors get more out of that turbine but eventually it becomes the limiting factor .

A .

[hy_rpm]

Well the ss1.5 is fitted with a 68mm compressor not the usual 71mm used in the gtrs or larger so will see how I go with the .86

I won't be able use the full potential of it with a g3 turbine as my injectors are too small anyway

[jay-rod]

Hey Stao

Wondering if u got my turbo safe and sound ?

[hypergear]

Sorry I didn't get any names in the package, I assume you are the guy from WA correct? if so then yes it has been received. just more power in this upgrade?