tte turbo boost

firepower · July 7, 2008, 08:54

just a thought , if the tte turbo uses a piggy back ecu could this be mapped to give more performance or do sp do the best map available s:?: :?: s:?: if this can be done could explain why my dyno at hypersports only give 173bhp as sp did not seem to map my car when the turbo was fitted .

Liz · July 7, 2008, 08:57

I thought that the ECU was sealed by TTE in order that it could not be tampered with? The SP240 on the other hand has a different ECU which CAN be tuned!

firepower · July 7, 2008, 09:04

it prob is liz just me thinking , i would like to increase the bhp a little bit as when my car was dyno'd at hypersport it was 173 bhp and other tte turbo's give nearer 200 bhp like yours liz .

aaronjb · July 7, 2008, 09:14

TTE ECU is sealed and non-tunable, however the turbos do seem to get fitted with varying levels of boost - IIRC Liz was close to 10psi, perhaps yours is lower. Obviously the TTE ECU will have a limited range for which it can accurately fuel - as will the rest of the fuelling system, so you can't just turn up the boost unless you know you are within those limits..

Don't forget that others may have the detcat pipe in place, which will free up a reasonable amount of horsepower, and/or different exhaust options which will all perform differently.

Liz · July 7, 2008, 09:15

Hmm, it does seem strange - you have the same set up as me, the Turbo - the exhaust and the downpipe, I have a Markiii pipe as well which I am told that I should not have s:roll: :roll: s:roll: and the TRD air filter - when did you have yours dyno'd?

Quote from: "aaronjb"Don't forget that others may have the detcat pipe in place, which will free up a reasonable amount of horsepower, and/or different exhaust options which will all perform differently.

According to his signature he has the decat pipe.

aaronjb · July 7, 2008, 09:41

Oops, Aaron did not read signature s:oops: :oops: s:oops: Aaron has the dumb, this morning.

evileye_wrx · July 7, 2008, 10:47

Is it not true tho that Dyno's are vastly inaccurate and that they are affected by a wide variety of conditions such as air temperature, atmospheric pressure, calibration? Also, if a car is dyno'ed on one machine it can give greatly different readings to another machine if the s ttings aren't corrected between machines?

Hasn't it been said in the past that certain mappers of unichip seem to give much better bhp numbers after a tune than others, and that this has been put down to their machine reading high rather than a better tune. As we all know anyway peak bhp isn't all that important in the grand scale of things a straight flat torque curve being much more useful.

Phil

firepower · July 7, 2008, 15:06

i had the dyno done before the decat pipe was fitted so perhaps my bhp would now be higher s:D

s:D and also as evileye says different dyno's can give different readings , the car still feels very quick when on boost and is running fine but as always as you get used to the performance you feel like you want more so perhaps i should have it dyno'd again to see what the numbers are now before going for a upgaded ecu or remap or larger injectors .
i would not mind increasing the bhp to around 220bhp or so but do not think i could justify spending £2000 on the car for that increase and i would not wish to risk the reliability of the engine by going to high

muffdan · July 7, 2008, 15:13

It isn't so much the power output that the internals don't like, it's the torque. If you want to acheive a higher output you're going to have to go for bigger injectors and a different ECU. Depending what you're boost pressure currently is, a cheap way to get more power could be just to go for a boost controller. I know Liz had problems with her higher boost pressure, but when I had the TTE and the SP240, it was running at 8.8 PSI with no problems.

Jason

firepower · July 7, 2008, 15:28

thanks for the advice but how long could the engine cope with running 8.8 psi boost and have there been any reliability problems with the sp 240s s:?: :?: s:?: that anyone knows of , i sound like a chicken don't i s:lol: :lol: s:lol:

muffdan · July 7, 2008, 15:48

8.8 is well below what TTE specified as the maximum PSI.

SP have ran their car for 20k I believe, and its been driven hard for those 20k. For the Elise SPT package, they wanted to know the same thing as you as TTE/Toyota/Lotus wouldn't be guaranteeing the engine or kit on an Elise and they'd have to provide the warantee themselves. They stripped their engine down and measured the wear and tear on the internals. After everything was checked, Matt said (and I quote): "It was a waste of time". Now they're shipping Elises with 250bhp conversions based on the TTET/SP240 package but with a bigger intercooler.

So basically, stock internals aren't a problem up to 240lb/ft torque.

Jason

firepower · July 7, 2008, 15:57

sounds good to me then , but stripping down the engine was not a waste of time if they can now honestly say that the internals can cope with higher boost pressure and the other sp 240 upgrade's s:D

s:D

muffdan · July 7, 2008, 16:27

Reliability wise, I did have a cracked pipe on the TTE precat where it joined the turbo. That significantly reduced power (by about 25bhp) until it was fixed. Might be worth checking yours.

Jason

firepower · July 15, 2008, 21:16

fitted a boost controller and terrified myself s:scared: :scared: s:scared: it was nothing to do with the cars performance but while setting it up the boost gauge went round to 1 bar S**t took my foot of the pedal immediately and drove slowly listening for any strange noises that would signify impending doom for my engine s:(

s:( everything seems ok and the car is running fine s:)

s:) as for the boost controller i don't know if it has given the car any more performance but i can now easily adjust the boost with it but i will not be cranking it up to much

Anonymous · July 15, 2008, 21:25

And you've got what controlling the fuelling? Forgive me for not reading back (8 pages is too much for me this time of night s;)

s;) ), but I don't think you're running any kind of piggyback at all (not including the TTE one), so I really wouldn't suggest putting the boost up at all: In fact, I'd remove it to make sure you can never overboost, just in case.

kanujunkie · July 15, 2008, 21:46

Dan's right, the TTE kit runs on MAP based fuelling, go over the end of that fuelling map and your in unknown territory, litterally for the fuelling, dependant on the way it works, it may just keep the maps highest duty cycle for the fuelling and then the overpressure cause a lean situation, or it may just cut out, to be honest i'm not sure how the TTE works on this score, want to risk it either way?

muffdan · July 15, 2008, 22:03

14PSI is high but shouldn't damage your engine over such a short period (a second or two right?)! You'll have ran very lean for a moment. Could you hear it knocking?

The maximum pressure the TTE piggy-back is mapped to deal with is 9.7PSI

If your turbo from the factory is running under this, then you can use your boost controller to raise and achieve up to 9.7PSI. I'd map it a little under to account for boost spikes. My controller records maximum boost achieved so you can easily tweak the pressure to keep the spike peak below your chosen threshold.

Even if you don't increase boost pressure with the controller, you can simply use it to hold the waste gate FULLY closed until you hit your desired boost pressure. This will massively reduce lag (but increase boost spiking). A good controller will cycle the solenoid to reduce the spikes whilst keeping the reduced lag gains. It can take a few runs to tweak this to get it right though.

Jason

firepower · July 15, 2008, 22:11

thanks for the advice folks at the moment the boost is set at 0.65 bar which is what the turbo was boosting to before i fitted the mbc , i do not intend to increase the boost any more but can reduce it a little if needed .
i thought the mbc would just transfered the adjustment of the boost from the actuator rod to the mbc , but i can easily return to stock set up if the mbc will cause engine trouble , the reason for posting this reply was to get feed back from others who know more than me so thanks again for your help s:D

s:D

muffdan · July 15, 2008, 22:27

A MBC can't reduce the boost. The minimum boost is achieved by the spring holding the waste gate closed.

Running at .65 bar is about right. If I were you I'd simply set the controller to the same pressure and just use it to reduce your lag, not that there's much anyway with the TTET!

Jason

markiii · July 16, 2008, 12:03

I don't believe an MBC can reduce lag you need an EBC for that

spit · July 16, 2008, 12:14

With a decent ball/spring valve I'm not sure about that: I noticed quite a difference at the stock wastegate setting. Whether and why an EBC's solenoid would have a different effect again, I dunno.

muffdan · July 16, 2008, 12:31

Quote from: "markiii"I don't believe an MBC can reduce lag you need an EBC for that

The waste gate will crack open below the Set PSI, with an MBC you can keep it fully closed up to the required PSI. It definitely made a difference to my lag. It should also reduce the boost threshold a tad too.

Jason

Anonymous · July 16, 2008, 12:54

You'll need to set it slightly below the required boot level though, else you risk it spiking and over-boosting.

markiii · July 16, 2008, 13:33

Quote from: "muffdan"
Quote from: "markiii"I don't believe an MBC can reduce lag you need an EBC for that

The waste gate will crack open below the Set PSI, with an MBC you can keep it fully closed up to the required PSI. It definitely made a difference to my lag. It should also reduce the boost threshold a tad too.

Jason

my understanding was that an MBC worked by bleeding sufficient pressure to fool the wastegate hence it alwyas sees some (the wastegate is always opening a bit, it;s not an off switch)

an EBC will allow you to completely keep teh wastegate shut as it sees zero psi until a preset point