Soarer Central: Archive through March 05, 2006

Soarer Central Transmission Shift kit - prices and results Archive through March 05, 2006

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Ben Evans
TryHard
Qld
"Master Power" Turbo 1J With Xtras

Posts: 331
Reg: 07-2005

Rating: N/A
Votes: 0 (Vote!)

Tuesday, February 28, 2006 - 05:56 pm, by: Ben Evans (Sbyder)

hmmm... well there goes my idea of having 300rwkw

I cant afford to get it rebuilt, so looks like i'll just be slower than i should be in order to save the box.

I want to tune my car to run 300RWKW when i need it, ie: drags, stupid guy in a skyline thinking he has a chance, etc...

I only want to run 200RWKW on low boost which will be 95% of the driving time.

I have a stage 2 shift kit(i think [only one copper pipe]), auto cooler, 3000ish stally and running synthetic fluid. The box is straight from a stocko soarer with 60,000kms on it.

What do you recon the chances are it'll hold up for a few years?

Ben

PS- i know the stally and shift kit helps with traction lose, got the back to slide out at 130km/h last night, scared the sh!t out of a guy in a commonwhore, ahahaha

Russell Newnham
Tinkerer
Victoria
TT

Posts: 20
Reg: 02-2006

Rating: N/A
Votes: 0 (Vote!)

Wednesday, March 01, 2006 - 11:42 am, by: Russell Newnham (Silvercar)

G'day Ben,

I have had one of the MV upgraded autos with 280 rwkW for a few years and it seems strong. I would only be guessing about 300 rwkw and a standard trans with a shift kit, but at over twice the standard power you would have to wonder about reliability. Also, Micheal is very experienced in making very tough trans for drag cars and based on this I would tend to believe him about the 265 rwkw.

You have a few more issues to work on yet as well though I think.

With 550 injectors and 280 rwkw I am at almost 90% duty cycle. In really cold weather and 300 rwkw I suspect you would have absolutely no safety margin.

Your ignition system would also need upgrading -although this depends upon the boost. If you can get the 300 kw at lower boost levels by using a bigger turbo your ignition may not break down - but big turbo means more lag.

Ignore this drivel if you have already sussed these issues out.

Chris Davey
TryHard
QLD
Corona

Posts: 448
Reg: 07-2005

Rating: N/A
Votes: 0 (Vote!)

Wednesday, March 01, 2006 - 11:55 am, by: Chris Davey (Chris_davey)

Ben: I am in the same boat as you

Although my car is a lot lighter so that should help keep gearboxes alive.

I think as always it comes down to how you treat it. If you are only going to use high boost at the strip and you aren't going to be doing that every week then I think it would last a while. You never know for sure but that is my hunch. Change the fluid reguarly and don't flog the crap out of it on the street all the time and minimal stalling it up will help also.

Russell: you know what is weird. Neil I think it was said he made 293rwkw at an average of 85% duty cycle with 440's. Do you know what your air fuel is at 280rwkw? I would hazard a guess that you are running richer than Neil. Which could be why your power is a little lower (or could be dyno difference

)

Also, re spark blow out. You say that running a larger turbo at lower boost will help prevent this. I would have thought that it would be the volume of air entering the cylinder rather than boost pressure. ie. 15psi on stock twins may not blow out but 15psi on GT42 might. Also, if this is the case wouldn't getting longer duration, higher lift cams mean spark would blow out at lower boost levels also.

Sorry about going off topic but I hope it helps people

Cihan Aday
DieHard
Victoria
JZZ30

Posts: 564
Reg: 07-2005

Rating: N/A
Votes: 0 (Vote!)

Wednesday, March 01, 2006 - 02:18 pm, by: Cihan Aday (Cihan)

15psi on ct12s or 15psi on a GT42 will make the same power. The only reason why they never do is because of efficiency and turbine size. Power is lost because of additional heat introduced to the intake charge by the smaller compressor running out of spec. Smaller turbos tend to have smaller exhaust AR's and turbines, this converts to backpressure which limits cylinder flow.

So you would be right on the money Chris. Cylinder flow is what blows out spark, a larger turbo = potentially, higher cylinder flow = more chance of spark blowout.

Cheers,
Cihan.

Simon Triantafillou
DieHard
NSW
Soarer Turbo

Posts: 544
Reg: 07-2005

Rating: N/A
Votes: 0 (Vote!)

Wednesday, March 01, 2006 - 02:27 pm, by: Simon Triantafillou (Soarer)

Cihan Aday wrote on Wednesday, March 01, 2006 - 02:18 pm:
15psi on ct12s or 15psi on a GT42 will make the same power. The only reason why they never do is because of efficiency and turbine size.

Make up your mind... first you say they make the same power, then in the following sentence, you say it can never happen.

Believe me, 20psi on twin hybrids gave me about 100kw less than my GT3540R on 20psi. Same boost, more airflow.

Chris Davey
TryHard
QLD
Corona

Posts: 454
Reg: 07-2005

Rating: N/A
Votes: 0 (Vote!)

Wednesday, March 01, 2006 - 02:32 pm, by: Chris Davey (Chris_davey)

Thanks for the confirmation Cihan

Maybe I should spend some money on a HKS DLI instead of some cams then

Emanuel Spinola
Moderator
NSW
JZZ30, UZZ32

Posts: 682
Reg: 07-2005

Rating: N/A
Votes: 0 (Vote!)

Wednesday, March 01, 2006 - 02:50 pm, by: Emanuel Spinola (Manny)

Boost doesn't blow out spark - it's not a candle with a naked flame blowing in the breeze ??

Russell Newnham
Tinkerer
Victoria
TT

Posts: 21
Reg: 02-2006

Rating: N/A
Votes: 0 (Vote!)

Wednesday, March 01, 2006 - 04:03 pm, by: Russell Newnham (Silvercar)

Did Neil really get 290+ rwkw with 440s? What was his duty cycle? Must have been close to 100%.

My tuning was done by the Motec dealer with a wide band oxygen sensor and was as lean as he thinks was safe. I think he must be a little more conservative than other, if others are getting these power figures with 440s. Either that or something else is not right, but I can't think what.

I was lead to believe that it is was increased cylinder pressure that causes problems with cylinder ignition which, in turn, is linked to increased boost.

Comments?

I tried a HKS DLI and it made no difference in my car, although some say they have observed improvements. I ended up with a Motec CDI which was bloody expensive but very effective.

Emanuel Spinola
Moderator
NSW
JZZ30, UZZ32

Posts: 683
Reg: 07-2005

Rating: N/A
Votes: 0 (Vote!)

Wednesday, March 01, 2006 - 04:35 pm, by: Emanuel Spinola (Manny)

Russell
My 550cc injectors were also at 95%+ duty cycle at 302rwkw which matches what others have since got as well as your own experience. To have a lower duty cycle with smaller injectors at similar boost/power figures defies logic and would indicate a comparison between apples and oranges.

Yep, elevated cylinder pressure (higher boost) requires a stronger spark to be able to arch from the central electrode to the ground electrode.

I personally can't praise the HKS DLI enough as my ignition system has been faultless at any boost level since I wired it in a few years back.

Cihan Aday
DieHard
Victoria
JZZ30

Posts: 567
Reg: 07-2005

Rating: N/A
Votes: 0 (Vote!)

Wednesday, March 01, 2006 - 05:30 pm, by: Cihan Aday (Cihan)

Simon Triantafillou wrote on Wednesday, March 01, 2006 - 02:27 pm:
Make up your mind... first you say they make the same power, then in the following sentence, you say it can never happen.

Believe me, 20psi on twin hybrids gave me about 100kw less than my GT3540R on 20psi. Same boost, more airflow.

Simon, they can make the same power at the same boost... But, as i said before it wont happen for various reasons (nothings perfect, simple physics interveins).

Things that effect power = flow(CFM), temperature, pressure, humidity.

Increase flow through engine = more power.
Decrease temperature = more power.
Increase intake charge pressure = more power.
Decrease humidity = more power.

By changing the turbo size, intercooler piping diameter, dump pipe size or various induction parts, you can increase the flow rate of the engine leading to more power. When we talk about flow we MUST consider RPM, naturally a larger turbo will make its boost later and hold that boost to higher RPM, which means more torque at higher RPM which means more peak power. Peak torque may be less or similar, but the flow rate of the engine will be higher because of the RPM associated with turbo size, not the turbo size directly.

Now that thats covered, take twin hybrids VS a single GT3540R running at 20psi as an example.

The hybrids compressors are running close too, or out of their efficiency island supplying the amount of flow required to presurise the whole induction system to 20PSI. Because of dump pipe diameter, we can assume that the exhaust turbine and low AR ratio of the Hybrids are causing additional backpressure to buildup as the boost raises.

Since the Hybrids are moving out of their efficiency range, the compressed air leaving the compressor raises in temperature. Also, because of the backpressure building up as boost raises - the flowrate of exhaust gas leaving the cylinder is limited/resticted.

If we look at the GT3540R setup, you would have a nice and large 4" intake pipe setup to a heatsheilded pod filter, 3" diameter piping off the compressor outlet into a large low pressure drop intercooler. The large compressor, designed specifically for larger than 500Hp applications is having no trouble supplying the airflow required to keep the intake charge pressurised to 20psi. It is within the high efficiency island of the compressor (usually btw %75-%78), hence, the intake charge is pressurised with the highest efficency (lowest temperature increase) possible with this compressor.
The exhaust turbine is suitably sized to flow the required volume of exhaust gasses, with a nice and large dump pipe and minimal bends. A suitibly exhaust side AR ratio would have been picked to find a nice balance between peak power, response and backpressure.

Your confusion is simple. Your saying bigger turbo = more power because of flow.. But in reality, the flowrate of air through the engine has little to do with the turbocharger used. It has everything to do with the size of the intake piping and subsequent restrictions before or after the cylinders.

For a given power, boost and RPM, it doesnt matter what turbo you use.. flow will be the same.

A 30cm 3" pipe at 10psi holds a same volume of air as a 30cm 3" pipe at 20psi, just more oxygen (in context). It doesnt matter what fills it, all that matters is what its filled 'with'. The turbo's job is to fill the pipe without heating its contents or causing a restriction when it comes out the other side.

Cheers,
Cihan.

Ben Evans
TryHard
Qld
"Master Power" Turbo 1J With Xtras

Posts: 333
Reg: 07-2005

Rating: N/A
Votes: 0 (Vote!)

Wednesday, March 01, 2006 - 05:40 pm, by: Ben Evans (Sbyder)

nah, i dont think so.

We need it MORE INDEPTH!

AHAHAHAHA

Paul Brockbank
TryHard
WA
Soarer TT

Posts: 410
Reg: 07-2005

Rating: N/A
Votes: 0 (Vote!)

Thursday, March 02, 2006 - 01:56 am, by: Paul Brockbank (Brockas)

Emanuel Spinola wrote on Wednesday, March 01, 2006 - 04:35 pm:
My 550cc injectors were also at 95%+ duty cycle at 302rwkw which matches what others have since got as well as your own experience. To have a lower duty cycle with smaller injectors at similar boost/power figures defies logic and would indicate a comparison between apples and oranges.

Has anyone experimented with options in the Wolf etc like 'batch fire'?

Also, if the ignition is retarded enough, whats to stop someone running leaner afr's?
Might be a pig to drive, but would stop you upgrading injectors.
(I ask because I have a friend who made 511rwhp on stock rb25det injectors, using a wolf. I know it sounds impossible, but its been discussed many a time).

As for the initial question about the shift kit.
My time went from 13.41 to 13.21 with just the installation of a stage 1.5 shift kit.