Doing the switchable TTC conversion on a auto

[lui]

So what's the pro's & con's of doing this remembering i have a Auto

 

I was thinking about doing the switchable TTC conversion to my car by fitting a two way switch in my dash so that by a flick of the button I can switch between Sequential mode to TTC mode

 

Is this flicking of the switch instant or does it keep messing up the brian of the ECU

 

Ive heard by doing this conversion theres great savings on fuel economy in TTC mode + what else do you gain

 

Does it effect the running of your engine management system in TTC mode

 

When switching between modes is it damaging you ECU

 

Also heard that it put loads of pressure on some pressure chamber somewhere

 

So is this a good conversion to do or should be well left alone what's your points of view appreciate any advice .

[Chris Wilson]

It's the most pointless thing I have ever heard of, you could also weld the diff up, fit wooden artillery wheels and metal tyres, and run fixed ignition timing if you are really set on undoing all the technology you have paid for

[SUPRALOOPY]

So what's the pro's & con's of doing this remembering i have a Auto

 

I was thinking about doing the switchable TTC conversion to my car by fitting a two way switch in my dash so that by a flick of the button I can switch between Sequential mode to TTC mode

 

Is this flicking of the switch instant or does it keep messing up the brian of the ECU

 

Ive heard by doing this conversion thers great savings on fuel economy in TTC mode + what else do you gain

 

Does it effect the running of your engine management system in TTC mode

 

When switching between modes is it damaging you ECU

 

Also heard that it put loads of pressure on some pressure chamber somewhere

 

So is this a good conversion to do or should be well left alone what's your points of view appreciate any advice .

 

its ok but nothing special. there are no gains in power, it is louder, and lots of fun in the dry. fuel economy is a bit better but nothing major. you just don't show any boost under 3500/4000 rpm. for noise factor its great but you loose the ftshhh at low speed

[SUPRALOOPY]

oh and nothing has gone pop yet, but i don't use it all that much now as i like the fftshhh at low speed to turn heads LOL

[wkdtime]

I use it all the time, 1 year now, i tried both and love this (ttc), i dont know why its always put down like this, this floats my boat, i like the fuel economy as im a student, power is still there if i want it, exhaust note is awsome. I cant fault it, but hey what do i know? i only been driving like this for a year and havent changed back.

 

Mine is a 6 speed btw.

[RedM]

It's the most pointless thing I have ever heard of, you could also weld the diff up, fit wooden artillery wheels and metal tyres, and run fixed ignition timing if you are really set on undoing all the technology you have paid for

 

Got any prices on the wooden artillery wheels and metal tyres? I'm looking for something a bit different.

[Steviekid]

I've ran in both TTC and sequential for long periods of time. Personally I much prefer sequential as I find the delay before you get any power in parallel really annoying and was only running in that setup to get around a problem my car had.

 

As for the noise it depends what you prefer! TTC with nur spec and double decat is LOUD, even at idle and almost to the point where it's too loud while cruising up the motorway! You also don't hear the turbos spinning or your dump valve at lower speeds anymore.

[Dash Rendar]

Doug (Class One) was telling me about his ETTC. He says on a long cruise (i.e. below 3500 rpm), he gets an extra 100 miles out of a tank!! That's a good enough reason for me to do it.

 

Just don't flick the switch with your foot down.

[Nic]

its ok but nothing special. there are no gains in power, it is louder, and lots of fun in the dry. fuel economy is a bit better but nothing major. you just don't show any boost under 3500/4000 rpm. for noise factor its great but you loose the ftshhh at low speed

 

I get positive boost at around 2800-2900rpm with the parallel setup.

 

I've run mine in parallel for quite a few years, mine is permanently converted by switching the vacuum hoses around. I have the emanage mapped for the parallel set up, I wouldn't recommend running TTC without someway of mapping the fueling/ignition.

 

I prefer the parallel operation, you lose a little low down, but gain mid revs with more power/torque, as you don't get the dip when the second turbo comes online, just smooth power delivery from around 2900rpm.

[wkdtime]

I get positive boost at around 2800-2900rpm with the parallel setup.

 

I've run mine in parallel for quite a few years, mine is permanently converted by switching the vacuum hoses around. I have the emanage mapped for the parallel set up, I wouldn't recommend running TTC without someway of mapping the fueling/ignition.

 

I prefer the parallel operation, you lose a little low down, but gain mid revs with more power/torque, as you don't get the dip when the second turbo comes online, just smooth power delivery from around 2900rpm.

 

Thank you, some positive feedback, from tried and tested!

[Pig]

If anyone needs the switch please let me know as i have one.

[Dash Rendar]

PMd.

[SupraJames]

Ok am thinking of doing this, Jake kindly provided me a link to MKIV.com tech section, which shows the mechanical way to do a TTC, so just after advice really what is the best way, mechanical or electrical via the ECU and a switch..?

[RobSheffield]

havent fully read through the thread to be honest, but iirc, the ECU needs a while of driving to relaearn the new way of boosting, and will run a bit rough in the meantime

 

for this reason i hope you arent planning on flicking the swithc back and forth a few times a week as i dont think that will work.

 

people tend to switch and stay, or at least stay TTC a while.

[JamesArup]

I did it too over a year ago. Been fine, had no problems. I run in standard SEQ mode most of the time, but every now and again it's fun to flick the switch and unleash hell .. it's LOUD. And it kicks you right back into the seat when both turbos come on together

 

I even wrote a guide on how I did it HERE if it helps?

 

Cheers, J

[JohnA]

Doug (Class One) was telling me about his ETTC. He says on a long cruise (i.e. below 3500 rpm), he gets an extra 100 miles out of a tank!! That's a good enough reason for me to do it.

 

Just don't flick the switch with your foot down.

 

When we're talking economy, we are off-boost or steady-state obviously. So it's a fair assumption that we will be in closed-loop operation all the time.

 

Under these conditions, the only way to improve the fuel economy (apart from reducing vehicle weight or friction losses) is to feed the engine with less air, so the ECU will pair it with less fuel.

 

During TTC there is a LOT less air fed to the engine under 4K rpm, especially with the throttle at low settings. A lot less air in comparison to sequential operation at the SAME throttle position.

 

So under these conditions, half throttle at TTC will produce the same airflow as 1/5 throttle in sequential (example). Fuel will be dispensed accordingly.

 

The fallacy is in trying to compare MPG at the same throttle settings --- that is not a fair comparison though.

 

If you stick to 80mph (or whatever) in TTC you'll realise that you need more throttle than sticking at the same speed (and same road) in sequential. Don't fool yourself that you're getting more power because the throttle is half-way: that is inevitable since the car is operating with no boost and the parasitic restriction of two turbos. Much worse than a N/A in fact.

 

If you do the same trip in sequential but try to keep your foot away from the throttle, then you'll see that MPG is the same. It's just not easy to restrain yourself in sequential since it is so much more responsive.

[wkdtime]

Ok am thinking of doing this, Jake kindly provided me a link to MKIV.com tech section, which shows the mechanical way to do a TTC, so just after advice really what is the best way, mechanical or electrical via the ECU and a switch..?

 

ELectric is the best way, but the easiest way is mechanical, the problem witht he mechanical is that when the car has not pressurised i.e no positive boost whens its been left overnight you sometimes get a a metal clicking sound which i think is the IACV valve fluttering, i maybe wrong, but its nothing to worry about. once pressurised it goes away.

 

plus points, louder exhaust (if that floats your boat), linear boost, 100 miles extra from a full tank (for me J spec).

 

Bad points, no boost until around 3-4k RPM, doesnt bother me though.

 

But if your Auto it maybe even worse. Ideally for manuals.

[Gazboy]

I'm sure right now there is someone on the Corvette forums asking how to disconnect cyls 6,7 & 8....

[wkdtime]

I'm sure right now there is someone on the Corvette forums asking how to disconnect cyls 6,7 & 8....

 

why would they do that? better fuel yeah? same power? course not, so pretty much pointless.

 

YOu dont get any less power with the TTC conversion, just late boost, if its a problem for some then switch back, this isnt a TTC VS sequential thread. Dont really see why theres always sarcy comments in regard to TTC.

[Gazboy]

why would they do that? better fuel yeah? same power? course not, so pretty much pointless.

 

YOu dont get any less power with the TTC conversion, just late boost, if its a problem for some then switch back, this isnt a TTC VS sequential thread. Dont really see why theres always sarcy comments in regard to TTC.

 

Peak power means jack shit if it's all at the top end. Power 'under' the curve is what counts, not the headline bhp- drive an E36 M3 evo back to back against a stock Supra- at ten tenths there is nothing in it, thing is, we don't drive at ten tenths.....

[JohnA]

I'm sure right now there is someone on the Corvette forums asking how to disconnect cyls 6,7 & 8....

There are actually current designs of multi-cylinder engines that disengage some of the cylinders on idle/low-load.

They do 'rotate' the cylinders all the time of course, but it makes sense as a concept.

[Gazboy]

There are actually current designs of multi-cylinder engines that disengage some of the cylinders on idle/low-load.

They do 'rotate' the cylinders all the time of course, but it makes sense as a concept.

 

Vauxhall did/started doing this around about 1990 in the Senator 24v- they used to shut off cyls 4,5,6 at low rpm's. I belive they dropped the idea (and the daft adverts) with the V6 Omegas????

[SupraJames]

So electrically is the way to go ?. Does look a little complex for me to attempt by myself. Have heard Emin does the TTC conversion, as he did Steve's (Mr Angry), is it worth having a word with him. The reason for wanting to do this TTC is explained in my post in Tech here

 

http://www.mkivsupra.net/vbb/showthread.php?t=63609

[wkdtime]

Peak power means jack shit if it's all at the top end. Power 'under' the curve is what counts, not the headline bhp- drive an E36 M3 evo back to back against a stock Supra- at ten tenths there is nothing in it, thing is, we don't drive at ten tenths.....

 

mate it dont mean jack shit so according to you big singles which have boost coming in late are pointless too? have you had ttc? well you would notice that when sprinting down a road or motorways you'll always be above 4k RPM, always in full boost.

 

The switch would mean pon motorway driving you would save loads on fuel, and when you want to drive it as a normal supe in sequential you can do so.

 

Where did the BHP come into this, i have clearly stated this is not a performance mod, i did it for the exhaust sound and fuel saving and i love the linear boost i get.

[Nic]

Peak power means jack shit if it's all at the top end. Power 'under' the curve is what counts, not the headline bhp- drive an E36 M3 evo back to back against a stock Supra- at ten tenths there is nothing in it, thing is, we don't drive at ten tenths.....

 

As said before, I would not advocate doing the TTC mod without someway of remapping the fueling and ignition, but with the car properly set up, you lose only a little bottom end and actually gain mid range torque/power, which is after all where you need it once you have got rolling.

 

The power delivery is smoother and you don't get a dip in power as the second turbo comes online, as you do in sequential mode. This is a dyno of mine running in parallel.