Where Is The Wow!

[N1GTR]

In pictures, here's the answer for people searching in the future;

Single;

Twins;

While the twins make more power, the single felt faster as there is a sharper rise in the graph towards the end of the scale.

[R31Nismoid]

Concidence with car setup, driver etc? I am pretty sure Superlap was dominated by guys with singles on even smaller motors The quickest NZ track GTR I am aware of runs a T04Z. The odds are a quickest track GTR would be running twins because the majority run twins anyway...

I was talking about his specific example @ Vic tracks for that power range/setup in a GTR - not EVO's/dedicated/stripped cars

Comparing near as possible - equals - with that comment

Of course there will be other cars, different setups, bigger budgets that will out perform the fairly specific example.

[Rolls]

Apparently you've never compared the torque and power curves for a car, where often torque will start decreasing near the top end, while power continues to increase.

You have misinterpreted what I said. More torque means more power at a specific rpm. Eg at 5000rpm if you increase the torque, you will always increase the power at that exact rpm. Looking at the relationship between torque and power you can see this will always be the case.

[Harey]

While the twins make more power, the single felt faster as there is a sharper rise in the graph towards the end of the scale.

I find it hard to come to that conclusion just by looking at those 2 dyno sheets. The powers are basically identical (using hp=kw*1.3) and its is very hard to compare the response of either as they are very different plots. The single is zoomed out so much and with speed at the bottom, the twins graph is too zoomed in and with rpm on the horizontal axis. I probably sound like a whinger, it is excellent info, I am just finding it hard to compare those two thats all.

[Rolls]

If they use less revs then, they are actually producing more torque to make the same power. The higher torque figure could be what makes them feel more 'wow'.

The same power will feel identical, you just get the benefit of not needing such high diff ratios hence it will feel faster with the same gearing, if you adjust the gearing to compensate for the higher up power then it will feel identical.

[N1GTR]

I find it hard to come to that conclusion just by looking at those 2 dyno sheets. The powers are basically identical (using hp=kw*1.3) and its is very hard to compare the response of either as they are very different plots. The single is zoomed out so much and with speed at the bottom, the twins graph is too zoomed in and with rpm on the horizontal axis. I probably sound like a whinger, it is excellent info, I am just finding it hard to compare those two thats all.

Look at the angle of the power curve, the sharper the angle the more agressive the "hit"

I understand the scales arent perfect, but the alternative is spending $10000 and trying it out for yourself.

[Harey]

Look at the angle of the power curve, the sharper the angle the more agressive the "hit"

I understand the scales arent perfect, but the alternative is spending $10000 and trying it out for yourself.

But thats my point if the scales arent even then how can you compare the angle?

Hahaha yup point taken, I wont be spending 10k to find out.

[R31Nismoid]

You take the speed reading, and power reading, and compare in excel if you cant work it out by looking

It'll give you a nice relative graph with just 4 or 5 plot points

[Lithium]

In pictures, here's the answer for people searching in the future;

Single;

Twins;

While the twins make more power, the single felt faster as there is a sharper rise in the graph towards the end of the scale.

Got propeganda? Clearly the most laggy/violent possible setup for that power level with a single and the smoothest possible for twins, that is SO not a fair representation. There are plenty of twin turbo setups which look like the plot you posted for the single turbo, and vice versa for single turbos with the twin turbo power curve.

[Rolls]

There are plenty of twin turbo setups which look like the plot you posted for the single turbo, and vice versa for single turbos with the twin turbo power curve.

Exactly, twins might come on ever so slightly sooner than the equivalent single, but theres not a huge difference. You can get laggy twins and a responsive single and vice versa. Both setups can be poorly setup to give you a massive kick when the come on boost.

Your best option is going the responsive setup and doing as nismoid said, use half throttle till 5000rpm and then stomp on it, that'll give you the best kick out of them all lol.

[N1GTR]

Got propeganda? Clearly the most laggy/violent possible setup for that power level with a single and the smoothest possible for twins, that is SO not a fair representation. There are plenty of twin turbo setups which look like the plot you posted for the single turbo, and vice versa for single turbos with the twin turbo power curve.

Dont think that was a single vs twins post

It was meant to show, in pictures, the "WOW" factor the OP was trying to find. Of course there's singles with good curves and twins with bad ones, no one's debating that, but they are the results ive personally had so to answer the question of how to feel the kick in the pants that should give people an idea of how to do it.

Wether its a fair comparison or not? Id say its a perfect comparison for this thread and not many others. Want it on the same scale? Do as Ash said, take the time and plot it out. Sure the scale isnt as fair as it could be, that just exaggerates the point

[Harey]

The same power will feel identical, you just get the benefit of not needing such high diff ratios hence it will feel faster with the same gearing, if you adjust the gearing to compensate for the higher up power then it will feel identical.

Point taken about the gearing reducing the effect of different rpm.

Although the same power level will feel completely different in a different weight car.

[bodge]

well T04Z cars would be making another 50-60rwkw given they usually run over 400 with ease.

Having been in various cars, im pinned to the seat with -5s.

obviously a bit more lag and another 50rwkw or so is going to feel different.

If the big single is better as you say, then the -5 equipped cars wouldnt be doing the faster lap times compared to the guys with the big singles from other workshops close by

The cars l am talking about that have big singles, have similar power to what my lady boy setup has, some have even less. From my personal experience my setup is no match for single setups. There may be alot of other factors that influence this, as my setup as you problably already know uses alot of stock standard components which in my opinion hinders my setup and gives me some doubt that the power figure that is quoted for my car is very optimistic.

As for -5 being better around a circuit l do agree to some extent and can see where the benifit can be from using a twin setup where it comes on boost earlier and has more bottom end to punch out of corners.

As for application l have no intention to chase other people around a circuit. My purpose was to have a quick street car that has the ability to run a 10 second pass with a change of tires and most importantly when it comes on boost you get that shove in the back and it puts a smile on my face, which at the moment it does neither.

[R31Nismoid]

If you cannot run a 10 sec pass on -5's, in daily street rubber - then you aren't using the pedals correctly.

Leewah ran 11.2 @ 130mph (normal daily tyres, no special rubber) with 347 @ the wheels...

So -5's, 20+ psi you have a LOT more. You dont even need to swap tyres.

End of the day if you don't like it then change it, there is always one that isn't happy.

[bodge]

If you cannot run a 10 sec pass on -5's, in daily street rubber - then you aren't using the pedals correctly.

Leewah ran 11.2 @ 130mph (normal daily tyres, no special rubber) with 347 @ the wheels...

So -5's, 20+ psi you have a LOT more. You dont even need to swap tyres.

End of the day if you don't like it then change it, there is always one that isn't happy.

I would like to see that. l heard it was 11.5 at 127mph.

Trust me l am using the "pedals correctly", l have been in a few 10 second cars and have raced a few ten second cars and there is no way in the world these super piss ant -5, with standard dump pipes running 25 psi of boost can cut a 10 second pass taking into consideration all of the other supporting mods are stock standard. I think we should agree to disgree. If you think GTRS with lady boy -5 are quick then good luck to you. As for my car making a claimed 380 rwkw, if it did why do l get my doors blown away with cars with less power? l think it proves a point that the dyno the car was tuned on is optimistic and if it is a true figure, l must be the only RB26 powered skyline in the whole of Australia making 380RWKW using stock standard parts.

[R31Nismoid]

Well given he is a good friend of mine and we were actually discussing it yesterday, I'd be inclinded to believe my version.

You aren't the only one, plenty of cars out there are using factory dumps and making 330-380rwkw.

If you are so dead certain the car doesn't have anywhere near the power spend $80 and put it on another dyno and see, would be the first thing i'd do.

(i've gone from racepace to dr.drft, varience of a whopping 10rwkw)

Anyway, proof will be in the pudding - I'll remember this thread for a time when i run a 10 with "super piss ant -5's!"

Till then

[DVS JEZ]

my old 419kw 32 GTR with T04Z ran 10.98 on street tyres. my mates 370kw GTR with -5s ran 10.89 on street tyres. on the street his would beat mine almost every where.

IMO big single is for dyno queen, external gate is for showing off. must admit i do miss the sound.

so different uses and benifits for each setup, each to their own, no point asking everyone on the internet which is better for their personal car because every one has their own opinions.

[FineLine]

Stop spammin nismoid or I'll lock this thread onya.

to the op. The wow factor is probably there but its spread a bit more evenly across the power band. As an example my original 25 and my current 30 run identical times and mph across the 1/4 mile yet the 30 feels tame compared to the hit I got from the 25.

Power levels are within a few hp of each other and if anything the 30 could probably go a tad better than the 25 but I drove it ladyboy fashion for fear of breaking the drive train, The 25 I used to flat shift and rev its tits off and whilst it was no lag monster it did come on like a hammer blow compared to the 30 which delivers it in a much more linear fashion.

If I were to placebo evaluate each engine without hard data I would tell you the 25 was probably the quicker but in real world that just isnt the case.

[Rolls]

Stop spammin nismoid or I'll lock this thread onya.

lol his posts are on topic and reasonable informative, i dont see the issue.

Point taken about the gearing reducing the effect of different rpm.

Although the same power level will feel completely different in a different weight car.

Yep, a lot of people forget to take into account weight and gearing, two big factors that can make a big difference.

[Turbo Dave]

I posted earlier about settling on an RB30 with -5's but am now leaning towards the RB26 I have with the -5's after reading about a few horror stories.

I don't mind spending the $$$$ on rebuilding and getting it all going but don't really want to spend it 2 or 3 times as I have read with the 30 conversions.

It was an old thread and things may have changed lately with the 30 conversions so I wont rule it right out for now but I'm not as keen as I was on the idea...

Will definitely be going for twins on my future setup to keep with a hopefully sleeper stock look under the bonnet.......