Jump to content
SAU Community

Hypergear Turbochargers and High flow Services Development thread


Recommended Posts

Further updates:

We've done few modifications to the oil galleries in side the bearing housing hopping for less oil drag on the balls, as well as separate oil feeding setup for the comp side collar. Feels very smooth to spin.

Following some advises, I've added anti surge slots onto the comp housing. In theroy it reduces pressure resistance to comp wheel while acts as additional suction ports once boost hit. So the general benefit would be faster response and quicker spool time. Hopefully it works as expected.

comphousing.jpg

compturbo.jpg

This time its a ATR43G3 duel ceramic ball bearing unit. I'm hopping for 300rwkws with very fast response.

Link to comment
Share on other sites

Putting it back into the car today. If every thing goes as planed should have it tuned the week after.

Also we are in the process of designing a duel ball bearing profile for OP6 high flow. Which has the capacity of 320rwkws with GT3076's response while looks stock standard. I will post photos of it when manufacturing process begins.

Link to comment
Share on other sites

To get that comp housing with the surge slots to a ATR43G3 assume you have the .60 comp will cost $260. or just $100 to drill the slots if you have the .70 version.

Upgrading with ceramic ball bearing cartridge would cost way too much at moment.

I’m still exploring the actual benefits of having those ceramic balls and try to get them to work at their peek efficiency. We will be able to build them at an acceptable price with small batches. I will announce the final price after having a mature product.

Link to comment
Share on other sites

Surge slots wont really make a difference unless the turbo is surging, it actually decreases the compressor effeciancy because it bleeds off air, it doesnt suck air through the holes, rather it releases air.

Link to comment
Share on other sites

Surge slots wont really make a difference unless the turbo is surging, it actually decreases the compressor effeciancy because it bleeds off air, it doesnt suck air through the holes, rather it releases air.

Not all true. engine normally surges on low rpms while throttle is half closed. So its really taking out the opposing force out of the comp wheel.

The exducer or the bottom blades throws air out so that leaves more access area.

Thats all theory, and every one believes in different things. So I'm testing it out.

Link to comment
Share on other sites

would a bov (plumb back) that leaks at idle/low throttle basically perform the same thing?

That only acts after the throttle is shut. The surge slots releases surge while accelerating.

Ie. exhaust wheel still spins while I’m half throttle, how ever the open on my throttle body does not create enough volume to swallow all that boost. So some bounces back, creating this Tu tu tu sound. I've seen quite few people mentioning that in the force induction section. But how much pressure exist while throttle is fully opened, If so, having the slots would show a increase in response.

Link to comment
Share on other sites

Oh I meant similar to how the stock bovs operate, how they leak on idle and very low load, if you could tweak it so they leaked on slightly higher load (10% throttle) to give a feedback effect similar to the anti surge slots, this way you could tune it to suit so that you dont waste too much energy with air recirculating, but also achieve the anti surge effect.

Link to comment
Share on other sites

Oh I meant similar to how the stock bovs operate, how they leak on idle and very low load, if you could tweak it so they leaked on slightly higher load (10% throttle) to give a feedback effect similar to the anti surge slots, this way you could tune it to suit so that you dont waste too much energy with air recirculating, but also achieve the anti surge effect.

It certainly feels like the case, I guess Nissan did put in lots of thinking in their design.

Also it leads me to think if the upper blades do any thing if the anti surge slots are set in between. I might just machine them all flat which leaves more induction area. Also I don't remember seeing any anti surge slots in the new machined wheeled turbos that Garrett is bringing out, apparently they don't run the lower blades.

Link to comment
Share on other sites

Oh I meant similar to how the stock bovs operate, how they leak on idle and very low load, if you could tweak it so they leaked on slightly higher load (10% throttle) to give a feedback effect similar to the anti surge slots, this way you could tune it to suit so that you dont waste too much energy with air recirculating, but also achieve the anti surge effect.

The stock Stagea bov has a 4mm hole which seems to bypass all the time, I filled the hole with a grub screw and it surged badly, only at part throttle, and the whole car surged in time with the noise, I removed it and noticed the part throttle surge gone and bov response back to normal. This will be part of why I cant hold 20psi though. Perhaps a solenoid bypassing when the throttle is at less than 50% is the go?

The stock turbo has a surge groove but no port, I had that machined out with the highflow.

I havent seen the stock RB valves close up, I didnt realise they were different.

Link to comment
Share on other sites

Photos of the bearings before installation:

bearings.JPG

Turbo's installed.

oncar2.JPG

Regarding to those anti surge holes, I think the best description would be driving with a massive air leak. Or unless I am driving with a massive air leak. They do make heaps of noises. I'll going to machine another housing without surge holes for comparison.

Link to comment
Share on other sites

Technically you should just do testing on the "abe" spec atr43g3 without the surge holes so you can compare the journal bearing to the twin ceramics as a direct comparison...

If you are also adding anti-surge slots as well you are adding another variable and can't show true results!

After you compare the bearing types, then move onto anti surge slots :laugh:

Link to comment
Share on other sites

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

    • There is a LOT of stuff that can be done, it all depends on how much time and money you want to spend on doing in.  Not all ECUs will be able to do it, and the more control you need the more time and knowledge needs to be put into making it work.  If you're willing to spend the time and money and have the right hardware and skills involved there's a lot that can be done. 
    • I am impressed with all this level of adjustment. I didn't expect all this possibility
    • Correct.  In the case of the 500kw dyno plot I showed you the car actually runs two boost control solenoids for boost control and a 5psi wastegate spring.  It allows me to control how much boost pressure is applied to both sides of the wastegate valve at any point and fairly accurately control boost target as a result. I've tuned it so that it's able to target anywhere from 5psi to 25psi depending on what's needed.  The target tables I've set up in that car are Gear vs RPM, so every gear has potential for a different boost (and torque) curve.   First and second gear have quite low boost targets, third gear actually has different target boost all the way through the rpm range as it's a stock RB25 gearbox - the boost targets have been chosen to maintain a peak of 600nm (what the owner has set as the maximum torque he's happy with putting through the stock 3rd gear) but it carries that to the rev limiter.   The boost curve to achieve that is something of a ramp up, then hold, then ramp up again and the power curve looks more like a flat line haha.  
    • so you can decrease or increase the boost depending on the diet as you wish?     by acting on the wastegate?
    • That's torque and power, it's all from a single run.  The boost curve is "held back" from it's peak target in the 3500rpm to 5000rpm range from memory, so it ramps hard to something like 18psi then climbs more progressively to 23psi nearer 5000rpm.   It makes the torque (and power) ramp more "natural" and less hard on parts and traction, it doesn't feel artificially held back.   
×
×
  • Create New...