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TTC vs Sequential - the results :)


cheekymonkey
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Does anyone know if i could get similar results to cheekymonkey with an emu??.......im guessing with the ability to adjust timing and fuelling results should be the same?

 

R Black, as for max power with full bpu and stand alone AEM, a certain AEM tuner reckons he saw 460bhp on standard tubbies!!

 

Im gonna possibly try the TTC mode with 650 injectors, EMU and 256/264 cams. I do find sequential very aggresive and unpredictable in the wet at times.

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Does anyone know if i could get similar results to cheekymonkey with an emu??

 

Yes you should be able to get similar results with the EMU.

 

I ran mine in TTC mode for around 5 years with an Emanage, I much preferred the linear power delivery, yes you lose response low down, but gain quite a bit mid to top end power, as you can see from the dyno results.

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I ran mine in TTC mode for around 5 years with an Emanage, I much preferred the linear power delivery, yes you lose response low down, but gain quite a bit mid to top end power, as you can see from the dyno results.

 

Sorry to quote you specifically here Nic, but yours was the most recent post :D

 

I don't understand how the peak power (i.e. once both turbo's are online and at full boost) is any different between TTC and normal. Regardless of whether the ECU is stock or aftermarket & mapped wouldn't the power output would be the same?

 

The delivery will be smoother during the transition point of course, which is what I think you guys are getting at.

 

I tried TTC on a stock ECU once before, not a nice experience unless you like to keep the revs up (IMO)

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Ive been running mine in TTC mode and love it. But i do need to get the mapping done on mine. How much does something like that set you back?

 

Surj

 

That would depend on which ECU you have installed. If you don't have any piggyback or standalone, then budget for that too.

 

If you don't have an unlocked one already it will be very expensive.

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I don't understand how the peak power (i.e. once both turbo's are online and at full boost) is any different between TTC and normal. Regardless of whether the ECU is stock or aftermarket & mapped wouldn't the power output would be the same?

 

seems like all the gains were doing through timing advance....as per Ryan's confirmation earlier

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Sorry to quote you specifically here Nic, but yours was the most recent post :D

 

I don't understand how the peak power (i.e. once both turbo's are online and at full boost) is any different between TTC and normal. Regardless of whether the ECU is stock or aftermarket & mapped wouldn't the power output would be the same?

 

The delivery will be smoother during the transition point of course, which is what I think you guys are getting at.

 

I tried TTC on a stock ECU once before, not a nice experience unless you like to keep the revs up (IMO)

 

You're probably right about the peak power, although from dyno graphs I've seen TTC tends to be slightly higher. Ryan's comment about flowing more air and timing adjustment may be the reason???

 

You do need to stir the gears a lot more in TTC to keep the revs up, mine was a lot more laggy in TTC compared to the GT35R I now have.

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what was your rw figure cheekymonkey??

 

Not sure - can that be calculated from my graph? Since they are measuring the rear wheels anyway and presumably extrapolating the flywheel power. /me waits for an expert :)

 

EDIT: I know it's not going to be as fast as yours until I fully de-cat so around 320-330 or something? :)

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Not sure - can that be calculated from my graph? Since they are measuring the rear wheels anyway and presumably extrapolating the flywheel power. /me waits for an expert :)

 

EDIT: I know it's not going to be as fast as yours until I fully de-cat so around 320-330 or something? :)

 

On one of the sheets Charlie gave you it will be on there. Think its the last page normally.

 

Plenty more to come on this setup because was in a constant battle with high egt's due to the 1st Cat restriction so had to richen off the mixture at the top end to around 11:1

 

Ryan

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On one of the sheets Charlie gave you it will be on there. Think its the last page normally.

 

Plenty more to come on this setup because was in a constant battle with high egt's due to the 1st Cat restriction so had to richen off the mixture at the top end to around 11:1

 

Oh, I get you. In that case, rwhp is 331 point something.

 

When toyota quote stock j-specs at 326 is that at the fly? I hope so :)

 

Ryan I am going to see CW about a first de-cat. Do you think the exhaust will become *MUCH* louder? You've seen my setup! If it's a little louder, that's OK - I just don't want to be pulled over as soon as I get on to the public road...

 

James

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When toyota quote stock j-specs at 326 is that at the fly? I hope so :)

 

Ryan I am going to see CW about a first de-cat. Do you think the exhaust will become *MUCH* louder? You've seen my setup! If it's a little louder, that's OK - I just don't want to be pulled over as soon as I get on to the public road...

 

James

 

Yes Fly

 

I dont think it will become much louder TBH with you as you will have to fit a restictor ring further down the exhaust anyway to control the boost.

 

If Wes can get away with the noise of his silver car then you will be fine.

 

Ryan

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I dont think it will become much louder TBH with you as you will have to fit a restictor ring further down the exhaust anyway to control the boost.

 

Where should the RR go - further end of the first de-cat or in the second de-cat?

 

Also, given that with no back-box I'll have even less restriction than most, do you think a 1.0 bar RR will be adequate?

 

Ideally I would like to have the RR restrict to 1.0 bar with the boost controller turned off, then raise the boost to 1.1 or 1.2 with the boost controller when I want a bit more fun, unless you tell me this isn't the best idea for whatever reason.

 

If Wes can get away with the noise of his silver car then you will be fine.

 

:D

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It would be interesting to know why the max power varies with the two set ups.

come on techies......

 

In sequential the second turbo produces the desired boost as set on a boost controller, i.e 1.2bar, where as the first normaly produces around 0.8bar.

 

In TTC would it be reasonable to assume both turbos are now producing the selected boost, i.e 1.2bar and therefore more air??

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Nice result but gotta agree the peak power should really be the same between sequential and TTC modes - after all they're both doing exactly the same thing at peak power RPM and means there was likely room for more timing advance up top in sequential mode.

 

Cheers,

 

Brian.

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It would be interesting to know why the max power varies with the two set ups.

come on techies......

 

In sequential the second turbo produces the desired boost as set on a boost controller, i.e 1.2bar, where as the first normaly produces around 0.8bar.

 

In TTC would it be reasonable to assume both turbos are now producing the selected boost, i.e 1.2bar and therefore more air??

 

both contribute to the boost pressure in either mode - the only difference is with sequential all 6 exhaust manifold branches are feeding the 1st turbo which is why you get more low end power and instant response because of how quickly those exhaust gases spool the 1st turbo. Then at the transition point you get a little dip as the VSV system diverts some of that boost to then pre-spool the 2nd turbo before then halfing the exhaust gases equally to feed each turbo. All TTC mode does is take away that sophistication by splitting the exhaust gases equally between the two turbos completely immediately.

 

Cheers,

 

Brian.

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both contribute to the boost pressure in either mode - the only difference is with sequential all 6 exhaust manifold branches are feeding the 1st turbo which is why you get more low end power and instant response because of how quickly those exhaust gases spool the 1st turbo. Then at the transition point you get a little dip as the VSV system diverts some of that boost to then pre-spool the 2nd turbo before then halfing the exhaust gases equally to feed each turbo. All TTC mode does is take away that sophistication by splitting the exhaust gases equally between the two turbos completely immediately.

 

That's the best explanation of the sequential system I've seen, thanks!

 

Would be interesting to see what Ryan says though, once both turbos are on-line there should be no difference. Obviously, in my case the difference in the peak power is because they were running slightly different maps but there must be a reason for that.

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As SimonB mentioned earlier on in this thread about when running in TTC it normally makes more boost, i found this the same with Cheekymonkeys car as well as my own personal car also. To make the comparison fair then with the graphs attached in this thread i added the extra duty with the boost controller to make the Seq Mode run the same boost as the TTC was running but found i was unable to get in as much timing (1-2 degrees) at the top end and that the EGT's were hotter also with the Seq setup.

 

The funny thing also was that the Injector duty was more also in TTC mode meaning it was supplying alot more air.

 

The main aim of this test though yesterday was not the final figure it was to see how much midrange was lost with the TTC setup after mapping to suit and we were all very pleased to see that after some adjustments had been made to the Ign and fuelling.

 

I must add again tho that on a stock ecu you will not get the same results!

 

Ryan.

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I can only imagine that the huge choke that the stock manifold running only one turbo puts on the exhaust system causes higher EGTs, by heatsoaking the manifold et al during the start of the power run. That and the backpressure causing more reversion possibly heats up the combustion chamber more initially, so you can run less timing.

 

A mapped TTC car is nice, a let-god-sort-it-out one isn't so nice :)

 

-Ian

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A mapped TTC car is nice, a let-god-sort-it-out one isn't so nice :)

 

-Ian

 

Agreed :)

 

Also Ian if you want to see the timing map just let me know via e-mail. As im sure some BPU owners with a EMB or EMU might like to try it.

 

Also if you have some datalogs of TTC and Seq have a look at the INJ Duty on both to see if they are the same as i seriously found the TTC to flow more at Top end. I was abit shocked to find it TBH.

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