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How to: TTC?


AlexJames

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Been searching for ages... cant find a link for how to do TTC?

 

And ideas?

 

Also... Will TTC give any noticeable benefit to fuel economy? surly the ecu is still shoving loads of fuel in where the 1st tubby should be? or does it re-set itself after a while?

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Been searching for ages... cant find a link for how to do TTC?

 

And ideas?

 

Also... Will TTC give any noticeable benefit to fuel economy? surly the ecu is still shoving loads of fuel in where the 1st tubby should be? or does it re-set itself after a while?

 

Is it the 5 min ttc mod you want, to try it, or are you looking for permenant?

 

I changed to TTC to drive to and from japfest and managed 32mpg.

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...so is that a trip to see Ryan then? or is it poss to do it myself?

 

Do you have a stand alone or piggy back ecu?

 

As Scott says, you need a stand alone ECU or something else to control the fuelling, then need it set up by a decent mapper (Ryan) unless you really understand what you're trying to do. You'll need an electronic boost controller too.

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I have a mines ECU, I don't think it's re-mappable. So what actually has to be done to change regarding the fuelling.? It says in the second article posted that the ECU will re-learn values the more you drive it in TTC mode and you may get puffs of black smoke until this happens.

 

Also, I have an AEM tru boost controller which is setup fine ATM, so if I put it in TTC mode, what would have to be changed?

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I have a mines ECU, I don't think it's re-mappable. So what actually has to be done to change regarding the fuelling.? It says in the second article posted that the ECU will re-learn values the more you drive it in TTC mode and you may get puffs of black smoke until this happens.

 

Also, I have an AEM tru boost controller which is setup fine ATM, so if I put it in TTC mode, what would have to be changed?

 

It will get a little better through time but there is only so much that the stock/mines ecu can change.

 

There is a lean spot around the 4k mark, as the 2 turbo's are coming online at once this will run a little bit TOO lean. Its probably a good idea to have an AFR gauge if you plan to run TTC mode for good without an ECU.

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Cheers Scott M. Running lean is one thing I don't want to be doing................ever. I think I'll be leaving mine in sequential mode for now :D

 

Thats the trouble though, the lean spot is inherent in both modes. I think the difference with TTC is that your on full boost a bit earlier than in sequential making it that little bit worse.

 

The fueling guru's would be able to explain it much better than me lol.

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Is that lean spot soing to be present on my Mines ECU?

 

Actually, I have some RR printouts at home, I'll check when I get in and report back.

 

Yeah, i have a mines too and its meant to be even leaner at the high end of the revs.

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I have a mines ECU, I don't think it's re-mappable. So what actually has to be done to change regarding the fuelling.? It says in the second article posted that the ECU will re-learn values the more you drive it in TTC mode and you may get puffs of black smoke until this happens.

 

Also, I have an AEM tru boost controller which is setup fine ATM, so if I put it in TTC mode, what would have to be changed?

 

You'd have to get someone to adjust the Mines ECU to get full benefits.

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i have a uk 550cc injectors and on the SRR in TTC it was actually running in the 9's so very rich, i also have water + meth injection so it runs a little rich anyway, i have ETTC and love it, can swith between twins or single mode, need to get a AEM or Solaris to really get the most out of it.

Can also run more boost on TTC i was only at 1.2 that day but mostly run 1.3 -1.4 for trackdays.

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i have a uk 550cc injectors and on the SRR in TTC it was actually running in the 9's so very rich, i also have water + meth injection so it runs a little rich anyway, i have ETTC and love it, can swith between twins or single mode, need to get a AEM or Solaris to really get the most out of it.

Can also run more boost on TTC i was only at 1.2 that day but mostly run 1.3 -1.4 for trackdays.

 

Isn't Apexi FC enough? I tought TTC just needs fuelling sorted, so why would you put fully blown standalone ECU?

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You'd have to get someone to adjust the Mines ECU to get full benefits.

 

I've heard there is no adjusting the Mines ECU.

 

Apparently not all Mines ECU's are the same either. Some have the rev limit raised, some don't.

 

Some are specified for the auto, some for manual.

 

I saw a thread once where you could put the serial number of the ECU into a jap website and you could get details from it.

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Thats the trouble though, the lean spot is inherent in both modes. I think the difference with TTC is that your on full boost a bit earlier than in sequential making it that little bit worse.

 

That's a bit misleading so here goes in an attempt to clear it up:

 

Toyota runs the first turbo at AFRs of 13:1. Due to the relatively low boost pressures and the low RPMs, this is perfectly OK and normal and is not a problem. When the second turbo comes on at 4000rpm there is a lightswitch-like dramatic increase in fuelling to handle the cooler air, higher pressures, and higher rpms.

 

The problem with the 5 minute TTC mod is that you get more than stock boost at 3500rpm or lower (depending on gear and engine load). You can easily see 1.2bar at 3500rpm, and while there is an outlying fuel map extrapolation for that, it's still aiming for 13:1 AFRs, and it's not very accurate at that. At those boost levels, with denser air from two turbos instead of one, you need a richer mix because the cylinders are going to start heating up fast. Add to that a massive boost spike at 4000rpm - up to 1.5bar - as the stock wastegate is only brought into action by the ECU at 4000rpm and above, and you are looking at a nice steady erosion of your pistons with detonation in my opinion.

 

A proper TTC conversion uses a boost controller to stop the boost spike, and an ECU of some sort to change the low down high boost mix to your more usual 11:1 area. You can also advance the ignition timing to make low down response better - with two turbos online the air charge is cooler. But that's not 5 minutes or "free" and you can't easily revert it back to sequential.

 

The ECU won't "learn" diddly squat about TTC, don't know where that came from. All it does regarding 'learning' is change ignition timing based on knock and closed loop (i.e. off-boost) fuelling. And some idling stuff but that's even more irrelevant.

 

-Ian

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