Jump to content
SAU Community

Recommended Posts

The bigger the torque spike the more of the push back in the seat feeling. As torque is proportional to acceleration.

The torque spike will be biggest with the smaller turbos running dickloads of boost, massive midrange spike.

I disagree with that...small turbos are more likely to come on early and give the car more low down torque but not a massive spike. Like the turbos used in turbo diesels, they aren't going to throw you back. And you can only run so much boost before it's outside it's efficiency range. Keep in mind we are talking about an RB25DET here, not a 2 litre. It's the big turbos that take forever to spool and throw on the power in the upper midrange...when they do it's a lightning bolt.

Anyway this "hold on feeling" is all subjective, no real point arguing it when to some people that's a turbo that holds strong throughout the range while others want a huge turbo to come on boost later and eat curbs.

I'm assuming you talking about 200kw turbos on SR motors? I found the 'push-in-seat' more epic in a couple of Jap spec s15s I drove with boost wound up high. But maybe thats because of the nature of the less torquey 4 bangers - lag.. then strong boost, RBs seem a lot mre linear and less crazy maybe because they already have the down-low torque pushing the car along..

Yeah my experience with the .86 I mentioned is on my SR. To be honest I consider a 2L 4pot to be more brutal in nature to a 6cyl of whatever size.

Whether it be some sort of lag and zap effect or that they actually product better torque for power is a difference of opinion really. I am happy for you to come and get an impression of my car once I change the exhaust housing. You will see there is no lag and zap effect but only a really strong pull effect through the midrange.

As a point of reference the TD05-18g SR I did recently made over 530nm on only 207kw, thats 300kw skyline material and it had peak torque at 4200rpm. I believe brutal delivery at a low RPM showcases actual torque, not that linear wind up toy feeling everyone normally misconceives as torque (pretty much what my setup has now, with 440nm at 5000rpm).

I reckon its the rate of increase of torque = crazy rush and quite often wheelspin.

Yes torque does give you the push in the back but if it is just slowly increasing then it doesnt feel like a rush. Remember someone posting about the LS7 Corvette ZR1 and saying it actually felt slower then his worked jap car with large turbo except when you looked at the speedo it would kill it. To me that is because the Corvette would have quite a flat torque curve whereas the jap car with large turbo would have no torque, no torque then a steep rise in torque.

Hahaha yeah but you're a drifter :P

For a street car just spinning your wheels at the wrong time can mean confiscation of your car for a month I think it is now.

I believe in Victoria it's now 25 to life.

I disagree with that...small turbos are more likely to come on early and give the car more low down torque but not a massive spike. Like the turbos used in turbo diesels, they aren't going to throw you back. And you can only run so much boost before it's outside it's efficiency range. Keep in mind we are talking about an RB25DET here, not a 2 litre. It's the big turbos that take forever to spool and throw on the power in the upper midrange...when they do it's a lightning bolt.

I wasn't talking small turbos, just smaller turbos. Eg one of hypergears 280kw turbos is going to give a bigger torque spike than his lag monster 320kw ones.

Harey I agree with what you are saying, it is the spike that does it really.

Edited by Rolls

I reckon its the rate of increase of torque = crazy rush and quite often wheelspin.

Yes torque does give you the push in the back but if it is just slowly increasing then it doesnt feel like a rush. Remember someone posting about the LS7 Corvette ZR1 and saying it actually felt slower then his worked jap car with large turbo except when you looked at the speedo it would kill it. To me that is because the Corvette would have quite a flat torque curve whereas the jap car with large turbo would have no torque, no torque then a steep rise in torque.

I used to have this debate all the time with my old man. Theres an obvious point where usable torque comes into play, that being the happy area in your powerband. V8s feel linear because they make all their torque too early, its the energy of a big motor that makes them fast. But imagine you could harness all the wheel spinning torque they make at 200rpm and translate that to full traction acceleration... now that would be crazy.

The problem is there are sheer limitations of that sort of thing, like tyres and road conditions.. But thats where our little turbo toys come into play. We start with a boring little donk and add a turbo onto it. The right turbo and cam choice can shift the torque around to suit what gear ratios were limited by, and create a fast car.

I once built a front wheel drive turbo, most epic car I have ever owned. The theory of the turning wheels pulling you around a corner was a total win (driving wheels in a RWD point straight, so how can you expect it to propell you around a corner?). I set about finding the perfect balance between power and delivery to make the car really quick through the hills. I was finding as an NA it would understeer because it had not enough power or not enough energy in certain gears, but then the right cam/turbo choice ended up with only 120kw but a car that could punch through corners 2 gears above what it was prior (with the obvious speed increase to match).

End of the day its not all about how much torque or power or even where... But how its delivered. Said it before and will say it again, delivery is KING.

I believe in Victoria it's now 25 to life.

NSW is no different... been there, done that.

Well arent you the pot calling the kettle black lol, Mr Corvette LS7 ra ra ra :nyaanyaa:

Its all relevant anyway, were talking about the rush you get from certain turbos and if thats torque or just the 'feeling' it gives you. I did my best to eleborate on my theories by describing how I utilised this 'rush' torque feeling to better drive a car. Be it FWD or not. Trying to describe that the feeling is relevant to actual torque and speed.

About as relevant as comparing it to a V8 :whistling: which Id say is entirely relevant in open discussion. Sorry if I didnt make my point clear enough, I hope I have now. Its hard to put everything down when at work.

I agree with Rolls and Harey saying it is the torque delivery that you feel. My G3 only really comes on strong at about 5000rpm, and you get a little bit of a shove but nothing extreme. Most likely due to the lack of VCT. Comparing that to a mates 25 with an almost identical setup to me except with a smaller TD05, so less torque and less power, his turbo comes on song at about 4000 and it gives you a real shove. My car is still quicker, his just feels more brutal.

I need a retune dammit happy.gif

As a point of reference the TD05-18g SR I did recently made over 530nm on only 207kw, thats 300kw skyline material and it had peak torque at 4200rpm.

No it didn't... Power is directly related to torque. If it made 530Nm at 4200RPM it is making 233kw at 4200RPM.

I just read all the replies so now I might ask you all a question

and also let you know what I was talking about when I mean "push back in seat"

So right now I am running a stock 33 with a greddy profec 2

Its running about 11PSI and bleeds to about 10PSI

When I take off in 1st and also putting my foot down in 2nd gear it gives me the rush feeling of I better hold on. No wheel spin or anything just that pressure that sits you in your seat

I was wondering if the SS1PU will do this but a fair bit harsher because its not a stock turbo or because the spool is close to the same as a stock turbo only the end result in kw gain changes?

Hope I am not to confusing guys :rolleyes:

**edit** The car wont be stock when the SS1PU is installed it will have all the extras to get 250rwkw

Edited by Kasko

I was wondering if the SS1PU will do this but a fair bit harsher because its not a stock turbo or because the spool is close to the same as a stock turbo only the end result in kw gain changes?

Hope I am not to confusing guys :rolleyes:

**edit** The car wont be stock when the SS1PU is installed it will have all the extras to get 250rwkw

Yes it will do it harsher because it is making a solid 25-50% more torque in the midrange. I think this will be the best turbo for the feeling you want. I have a gcg turbo that comes on strong about 4k, and I describe it as the same thing, about 3.5-4k it just snaps you back in the seat due to the midrange, it then tapers off towards redline.

I agree with Rolls and Harey saying it is the torque delivery that you feel. My G3 only really comes on strong at about 5000rpm, and you get a little bit of a shove but nothing extreme. Most likely due to the lack of VCT. Comparing that to a mates 25 with an almost identical setup to me except with a smaller TD05, so less torque and less power, his turbo comes on song at about 4000 and it gives you a real shove. My car is still quicker, his just feels more brutal.

I need a retune dammit happy.gif

Hahaha but thats not what I am saying. I am saying the G3 should give you much more of a rush due to the change in torque (steepness of the torque curve). The smaller TD05 should be quite a gradual build of boost whereas the G3 typically will be more nothing and then holy sh*t. You need to get your setup sorted so its like the latter :)

Im so fricken excited for all the things happening to the car in the next few months!

When everyone was talking about the big laggy turbos making the feeling im looking for I was thinking about how I get the feeling from my stock one launches in 1st and and that surly isnt a laggy turbo

Hahaha but thats not what I am saying. I am saying the G3 should give you much more of a rush due to the change in torque (steepness of the torque curve). The smaller TD05 should be quite a gradual build of boost whereas the G3 typically will be more nothing and then holy sh*t. You need to get your setup sorted so its like the latter :)

That's... Exactly what I said. Lol.

Most likely because of my lack of VCT, my G3 doesn't build torque very quickly. It still creates a lot of torque, but it's not a steep curve. My mates TD05 actually has a steeper torque curve, despite being more responsive. It makes less peak torque and less peak power, but the shape of his curve gives his car more of the rush.

Kasko, you need to be aware that the feeling you're after doesn't last, you do get used to it. Like you keep referring to your stock turbo giving the feeling you're after, yet if I was to go for a ride in a stock GTT I bet it would feel like I was in a Getz.

A good way to reset that feeling is to have it off the road for 3 months, you forget what it is like completely, get back in it and go wholy shit this is ridiculous all over again heh.

A good way to reset that feeling is to have it off the road for 3 months, you forget what it is like completely, get back in it and go wholy shit this is ridiculous all over again heh.

This is what I do :D Having another daily is great.

No it didn't... Power is directly related to torque. If it made 530Nm at 4200RPM it is making 233kw at 4200RPM.

No worries, DVS JEZ on this forum tuned it - he has the dyno data for it also :action-smiley-069:

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

    • Place the new daughterboard in the case and mount it using the 3 small black rivets provided, and reconnect the 3 factory ribbon cables to the new board Then, use the 3 piggyback cables from the daughterboard into the factory board on top (there are stand offs in the case to keep them apart. and remember to reconnect the antenna and rear cover fan wires. 1 screw to hold the motherboard in place. Before closing the case, make a hole in the sticker covering a hole in the case and run the cable for the android unit into the plug there. The video forgot this step, so did I, so will you probably. Then redo the 4 screws on back, 2 each top and bottom, 3 each side and put the 2 brackets back on.....all ready to go and not that tricky really.      
    • Onto the android unit. You need to remove the top screen because there is a daughterboard to put inside the case. Each side vent pops out from clips; start at the bottom and carefully remove upwards (use a trim remover tool to avoid breaking anything). Then the lower screen and controls come out, 4 screws, a couple of clips (including 3 flimsy ones at the top) and 3 plugs on the rear. Then the upper screen, 4 screws and a bunch of plugs and she is out. From there, remove the mounting brackets (2 screws each), 4 screws on the rear, 2 screws top and bottom and 3 screws holding in the small plates on each side. When you remove the back cover (tight fit), watch out for the power cable for the fan, I removed it so I could put the back aside. The mainboard is held in by 1 screw in the middle, 1 aerial at the top and 3 ribbon cables. If you've ever done any laptop stuff the ribbon cables are OK to work with, just pop up the retainer and they slide out. If you are not familiar just grab a 12 year old from an iphone factory, they will know how it works The case should now look like this:
    • Switching the console was tricky. First there were 6 screws to remove, and also the little adapter loom and its screws had to come out. Also don't forget to remove the 2 screws holding the central locking receiver. Then there are 4 clips on either side....these were very tight in this case and needed careful persuading with a long flat screw driver....some force required but not enough to break them...this was probably the fiddliest part of the whole job. In my case I needed both the wiring loom and the central locking receiver module to swap across to the new one. That was it for the console, so "assembly is the reverse of disassembly"
    • But first....while I was there, I also swapped across the centre console box for the other style where the AV inputs don't intrude into the (very limited !) space.  Part# was 96926-4GA0A, 284H3-4GA0B, 284H3-4GA0A. (I've already swapped the top 12v socket for a USB bulkhead in this pic, it fit the hole without modification:) Comparison of the 2: Basically to do the console you need to remove the DS and PS side console trim (they slide up and back, held in by clips only) Then remove the back half of the console top trim with the cupholders, pops up, all clips again but be careful at the front as it is pretty flimsy. Then slide the shifter boot down, remove the spring clip, loose it forever somewhere in the car the pull the shift knob off. Remove the tiny plastic piece on DS near "P" and use something thin and long (most screwdrivers won't fit) to push down the interlock and put the shifter down in D for space. There is one screw at the front, then the shifter surround and ashtray lift up. There are 3 or 4 plugs underneath and it is off. Next is the rear cover of the centre console; you need to open the console lid, pop off the trim covering the lid hinge and undo the 2rd screw from the driver's side (the rest all need to come out later so you can do them all now and remove the lid) Then the rear cover unclips (6 clips), start at the top with a trim tool pulling backwards. Once it is off there are 2 screws facing rearwards to remove (need a short phillips for these) and you are done with the rear of the console. There are 4 plugs at the A/V box to unclip Then there are 2 screws at the front of the console, and 2 clips (pull up and back) and the console will come out.
    • So, a bit of a side trip, but one that might be interesting for people with JDM cars and japanese head units. I know @Pac previously posted about a carplay/android auto adapter he installed which used the AUX input, and @V35_Paul put in one of the Tesla style units that replace both screens. The option I went with was a Lsait LLT-YF-VER5.87_2 (https://www.alibaba.com/product-detail/Lsailt-8GB-Android-Multimedia-Interface-for_1601187633672.html). Price was $1,150 for a single unit although they are much cheaper if you are willing to buy 2....$857ea. Make you you get the version 2 not version 1, it is faster and has a better UI - this is the manufacturer listing: http://www.lsailt.com/product/348.html. BTW if you've never bought from Alibaba before, don't be concerned....these guys can't stay in business unless they are responsive, ship fast etc, they were excellent (probably faster shipping than most local places) So, this was my task for a lazy Sat afternoon....looks complex but was all done in a few hours (it probably helps that I had some of it apart before so it was a bit familiar). I also decided to add a HD USB drive recorded at the same time and the unit also supports an aftermarket reverse cam (if you don't want to retain factory) and also AV in and HDMI out It looks much worse than it is, in fact in was genuinely all plug and play (no custom wiring at all). This video was pretty good (skipped a few steps), unfortunately they are an Aussie seller but no longer sell this unit (I guess Carplay/AA adapters are easier to install and much cheaper) https://www.youtube.com/watch?v=T5hJfYOB8Dg
×
×
  • Create New...