Jump to content
SAU Community

Recommended Posts

On 07/04/2021 at 9:18 AM, RB335 said:

8474 didn't deliver anything special in my application, 2.8L high comp RB26 2.8l.  WIth a 1.05 rear, compared to the 9180 it behaved very similar.  It was quite more eager to come onto power faster on full throttle in 1st and 2nd gear, but it felt so restricted as soon as you got it moving.  The 9180 didn't feel like it was choking the engine as much, overall felt much more healthy and a better match  

The 9274 was the next turbo I was going to try, but it looked like it would just be an extension of the drawbacks I had with the 8474.  74mm wheel simply too restrictive to swallow all the flow the larger compressor can give.  Wasn't impressed with the 9280 from very limited testing I done

Why are you chucking money at all these different turbos when your setup isn't optimised?

On 4/1/2021 at 1:19 PM, Robo said:

I went from a 7163 to 8374 to 8474 to 9174 and I am glad I did, it's an incredible turbo with amazing spool.

My car is not a Skyline sorry, it's an EVO X with sleeved and built 2.16cc engine (plazmaman IC, direct port meth injection, S2 cams, sequential 6 speed etc)

8474 was twinscroll  IWG and only 0.8 A/R rear

9174 was twinscroll EWG with 1.45 A/R rear

The 8474 came onto boost way too hard and made it undrivable (like between 3.5k to 4.5k was vertical on the dyno).

The 9174 we all thought being so much bigger rear housing would be lag city but surprisingly it was about the same as the 8474 (we only changed the turbo and nothing else). I see 1.5bar (22psi) by 4,300rpm. I am not done yet, I'm increasing the downpipe and going to S3 cams (Time attack car).

Rob

^ So many people just don't get this, it's a well known fact that too small a turbo while nice for a dyno sheet saying "look kuntz here is superior spool low down power" it is totally shit for applying power after apex to corner exit.

On 4/1/2021 at 1:19 PM, Robo said:

 

 

 

1 hour ago, RICE RACING said:

^ So many people just don't get this, it's a well known fact that too small a turbo while nice for a dyno sheet saying "look kuntz here is superior spool low down power" it is totally shit for applying power after apex to corner exit.

thats a very non-DBW way of thinking of things. a responsive turbo gives you more control authority.

  • Like 1
45 minutes ago, burn4005 said:

thats a very non-DBW way of thinking of things. a responsive turbo gives you more control authority.

That's how the European cars do it, it's not a pedal for the throttle, it's a pedal to request for torque.

On 4/9/2021 at 2:51 PM, burn4005 said:

thats a very non-DBW way of thinking of things. a responsive turbo gives you more control authority.

The DBW does nothing but mask the problem, it is still totally pointless restricting the engine when you actually need the power, the DBW cant magically 'add' power. And this is why its important to use the right turbo, way too many people get hung up on the modern bullshit as a panacea for bad fundamental choices, a loss is a loss, too small a turbo gives power where its useless and not enough where its needed, simple.

11 hours ago, RICE RACING said:

The DBW does nothing but mask the problem, it is still totally pointless restricting the engine when you actually need the power, the DBW cant magically 'add' power. And this is why its important to use the right turbo, way too many people get hung up on the modern bullshit as a panacea for bad fundamental choices, a loss is a loss, too small a turbo gives power where its useless and not enough where its needed, simple.

Thats a pretty "broad statement " turbo size pends on many things. Too big of a turbo is exactly the same as too small of a turbo it depends where you drive the car as to where you need the grunt.

 

2 hours ago, Mick_o said:

Thats a pretty "broad statement " turbo size pends on many things. Too big of a turbo is exactly the same as too small of a turbo it depends where you drive the car as to where you need the grunt.

 

No it is not exactly the same, you are taking me out of context, I realize its a forum and everyone thinks their opinion is worthwhile but its actually useless cause if you take note I replied to the OP who brought it up and he shared his real world track experience and I have same experience personally and through end users.

Too small a turbo is a massive mistake on a track car end of story.

It is similar to adding traction control, this does not solve issue of lack of grip, the TC cant make more grip it can only let you use closer to the limit of what your car has. Too small a turbo cant be made to have more power than it can deliver, so the DBW comment was just a pointless bit of dibble put up to make someone feel good about themselves NOT to understand the point of the OP's post....... just another reason why forums are forums in the main part.

Except a smaller turbo often has more area under the curve. Realistically if you're serious you would evaluate the RPM ranges you use most commonly and do some math to determine where you'd get the most gains.

DBW and TC can make for better lap times for better auto-management of torque so the driver can have an easier time getting the thing out of a corner. A bigger, laggier turbo making less power in this scenario (if its noticeably less than the amount that TC and DBW combined with the smaller turbo can provide) would be slower.

But yeah if you're at this point you probably have telemetry you can lean on on to see what RPM's you're actually in, when you're in them, and how much average power you're making when you want it.

I won't say bigger is better but generally if you're under 5000rpm you may be in the wrong gear.

  • Like 1

100% agree with above.

And from practical experience I am 1.5-2secs slower on a Rally Sprint over a 150sec lap when using a 8474 vs 8374.

There are times in 2nd gear I am below 4000rpm and that’s where the smaller turbo picks up time even though I have less power and top end speed.

  • Like 1
On 11/04/2021 at 1:52 PM, Kinkstaah said:

Except a smaller turbo often has more area under the curve. Realistically if you're serious you would evaluate the RPM ranges you use most commonly and do some math to determine where you'd get the most gains.

DBW and TC can make for better lap times for better auto-management of torque so the driver can have an easier time getting the thing out of a corner. A bigger, laggier turbo making less power in this scenario (if its noticeably less than the amount that TC and DBW combined with the smaller turbo can provide) would be slower.

But yeah if you're at this point you probably have telemetry you can lean on on to see what RPM's you're actually in, when you're in them, and how much average power you're making when you want it.

I won't say bigger is better but generally if you're under 5000rpm you may be in the wrong gear.

it gets more complicated than that as you also adjust what gear you are in based on the power available in rev band....  for example in my old RX8 i was always in lowest gear i could find so i was revving the thing out as much as i could as all the power is up top, now im using a few gears higher as all my torque is in the middle of the rev range. I guess theres a point that you will also adjust your driving based on the powerband...

  • Like 1
On 4/11/2021 at 11:00 AM, RICE RACING said:

No it is not exactly the same, you are taking me out of context, I realize its a forum and everyone thinks their opinion is worthwhile but its actually useless cause if you take note I replied to the OP who brought it up and he shared his real world track experience and I have same experience personally and through end users.

Too small a turbo is a massive mistake on a track car end of story.

It is similar to adding traction control, this does not solve issue of lack of grip, the TC cant make more grip it can only let you use closer to the limit of what your car has. Too small a turbo cant be made to have more power than it can deliver, so the DBW comment was just a pointless bit of dibble put up to make someone feel good about themselves NOT to understand the point of the OP's post....... just another reason why forums are forums in the main part.

ok I'll bite.

traction control gives you CONTROL to allow you closer to the limit. if it is done correctly, you will be faster.

DBW doesnt give you more power. it gives you CONTROL of available power. if it is done correctly, you will be faster. "big turbo good" isnt the answer. the post was about the 8474 coming on too hard. DBW can linearise the power developed. and compared to an 9280, sure the peak power isn't as high, but the spread of controllable power is wider. a larger turbo just gives you a smaller band you have torque demand authority. if your gearing dictates a second gear hairpin or third gear chicane complex down to 4000rpm, i garantee the smaller turbo with DBW torque demand will get you around it MUCH faster than a larger turbo with a cable throttle.

if we are talking about turbos of this size you dont need more peak power at the apex, you need more control  of midrange torque and having a large turbo so it doesn't come on as hard is a bandaid solution. sure, at QR "big turbo good". but at lakeside/morgan park its not useful.

  • Like 1

I've been doing traction control before most of you could walk lol. You missed the point actually you dont get any of it I think as you are not an engine person nor someone who drives properly on track or road? just guessing there cause I cant really work out other than you wanting to type to read back your own posts what is the point.

You have two experienced people telling you why a wrong (smaller) turbo is inferior yet you keep on about doing it the ghetto way and not addressing any points.

I get it if you want to go slower and stress the engine more, other than that don't really get what you are on about honestly.

  • Like 1
1 hour ago, burn4005 said:

I need a 700kw turbo and a cable throttle to drive my no aero no slicks car on a twisty track because more peak power is faster. got it.

You're still not getting it m8. You need to stop running that shitty e85, toss the emtron in the bin and upgrade to a syvecs and rice racing water injection kit tuned by the rice master himself. 

Then and only then will u truly understand what quick is m8.

 

  • Like 1
  • Thanks 1
  • Haha 3

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

    • Fark what are the changes of that snapping like that, clean. Nek minnit, custom radiator goes in, with built in oil cooler like those discontinued PWR ones from yesterdeacades ago
    • I thought I'd do a write up on an auto transmission fluid change for a the nissan 7 speed Automatic. At some stage the genius engineers decided that the fluid in the trans was "for the life of the transmission", (which seems kind of self supporting to me) and removed the dip stick and fill tube (funnily enough there is still a casting for it). Anyway, for this job you do need 2 specialist tools in addition to regular hand tools, jack and good chassis stands. You need a way to pump fluid up to the transmission; I got one of these but there are plenty of other options: https://www.ebay.com.au/itm/364584087070 Don't trust the generic listing though, it does not come with the required adapter for the Nissan 7 Speed. You need one of these, can't do the job without it: https://navarapart.com.au/product/genuine-nissan-patrol-y62-d23-np300-navara-re7-dipstick-fill-connector1 You need a heap of compatible transmission oil. Could be Nissan, could be anything else rated for Nissan Matic S. You need at least 10 litres, I had 15 to give it a better flush... Also, you need some biiig oil catch trays, at least one of these, or bigger if possible (volume was fine, size was very marginal): https://autobarn.com.au/ab/Autobarn-Category/Tools-%26-Garage/Specialty-Tools/Oil-Service/Garage-Tough-Oil-Drain-Pan-Black-16L---GT1068/p/TO03191 Finally, a measuring jug is very useful if your pump does not have volumes marked on it, I got a 6l one: https://www.repco.com.au/oils-fluids/fluid-accessories/measuring-jugs/penrite-measuring-jug-6l-pmj006/p/A5322648 Oh, and gloves.....this stuff is horrible (not as bad as diff oil, but getting there) ....First, jack up your car.....
    • So I mentioned the apprentice, @LachyK helped take the bonnet off. We just undid the nuts on the hinges and unclipped the gas struts, then pulled the bonnet back a little as the front was catching on the front bar.  I had a good look at everything today and have removed the rams, repaired/reset the hinges and bolted it back together like it never happened. I'll do a separate write up on the repair, and I also removed the poppers from the Fuga today too to save grief down the road.....as said above it is at least $5k to repair retail. I'm also happier about my ability to prepare a race car, and less happy about Nis-nault's engineering (I can hear @GTSBoy sAfrican Americaning) because the top hose of the radiator didn't slip off.......it snapped clean off. By practice I put the hose clamp hard up against the flare on a neck to make it least likely to ever move (thanks @Neil!). I guess that puts a little more pressure on the end of the pipe as it is further away from the rad, but still, that is pretty shit. I've put it back on for now as there was a fair bit of neck still there, but obviously there is no lip on the neck any more so I don't think I'll track it again until I have a new rad. Speaking of which....more research required. It looks like Koyo makes a standard size radiator in ally which I'll grab in the meantime, but I really want something thicker so might have to go custom in the medium term (ouch) Coolant still needs a refill and I have the pressure tester on it over night, but other than a wash down of the engine bay it seems alright. And @MBS206 noted something noisy on the front of the engine and I think I agree....time for a new accessory belt and tensioners I think.
    • our good friends at nismo make a diff for it, I have one (and a spare housing to put the centre in) on the way. https://www.nismo.co.jp/products/web_catalogue/lsd/mechanical_lsd_v37.html AMS also make a helical one, but I prefer mechanical for track use in 2wd (I do run a quaife in the front, but not rear of the R32)
    • What are we supposed to be seeing in the photo of the steering angle sensor? The outer housing doesn't turn, right? All the action is on the inside. The real test here is whether or not your car has had the steering put back together by a butcher. When the steering is centred (and we're not caring about the wheel too much here, we're talking about the front wheels, parallel, facing front) then you should have an absolutely even number of turns from centre to left lock and centre to right lock. If there is any difference at all then perhaps the thing has been put back together wrongly, either the steering wheel put on one spline (or more!) off, and the alignment bodged to straighteb the wheel, or the opposite where something silly was done underneath and the wheel put back on crooked to compensate. Nut there isn't actually much evidence that you have such a problem anyway. It is something you can easily measure and test for to find out though. My money is still on the HICAS CU not driving the PS solenoid with the proper PWM signal required to lighten the load at lower speed. If it were me, I would be putting either a multimeter or oscilloscope onto the solenoid terminals and taking it for a drive, looking for the voltage to change. The PWM signal is 0v, 12V, 0V, 12v with ...obviously...modulated pulse width. You should see that as an average voltage somewhere between 0V and 12V, and it should vary with speed. An handheld oscilloscope would be the better tool for this, because they are definitely good enough but there's no telling if any cheap shit multimeter that people have lying around are good enough. You can also directly interfere with the solenoid. If you wire up a little voltage divider with variable resistor on it, and hook the PS solenoid direct to 12V through that, you can manually adjust the voltage to the solenoid and you should be able to make it go ligheter and heavier. If you cannot, then the problem is either the solenoid itself dead, or your description of the steering being "tight" (which I have just been assuming you mean "heavy") could be that you have a mechanical problem in the steering and there is heaps of resistance to movement.
×
×
  • Create New...