Milo500 Posted December 4, 2015 Share Posted December 4, 2015 Hi guys, I have a 1995 single turbo converted originally tt supra. I have installed a greddy profec bc and will be putting on the hks fcd, but it has the stock ecu at the moment. What is a safe amount of boost to run without changing the fueling/ecu? Cheers, Tom Quote Link to comment Share on other sites More sharing options...
j_jza80 Posted December 4, 2015 Share Posted December 4, 2015 On stock turbos, 1.2 bar for a j spec Quote Link to comment Share on other sites More sharing options...
np89 Posted December 4, 2015 Share Posted December 4, 2015 On stock turbos, 1.2 bar for a j spec He said its a single converted car. Without an FCD mate you wont be able to run over about 0.8 I think - - - Updated - - - and max boost fuel wise depends on how much air your turbo will actually flow, not so much the boost pressure Quote Link to comment Share on other sites More sharing options...
Milo500 Posted December 4, 2015 Author Share Posted December 4, 2015 Hi buddy, This is what i was thinking, how do i got about finding how much mine flows, is just a single ar/70. After the fuel cut defender goes in this afternoon, roughly what would you think is safe so it doesn't lean out (presure wise so i can set my boost controller to limit it)...pretty sure it's a stock fuel system. Cheers Quote Link to comment Share on other sites More sharing options...
np89 Posted December 4, 2015 Share Posted December 4, 2015 I wouldnt have the in depth knowledge to advise specifically mate. If you could find it somewhere i would GUESS if you can match the stock airflow at 1.2 bar on the stock turbos that would be safe but ive no idea. Pressure and volume and two entirely different things Quote Link to comment Share on other sites More sharing options...
Nic Posted December 4, 2015 Share Posted December 4, 2015 (edited) Hi guys, I have a 1995 single turbo converted originally tt supra. I have installed a greddy profec bc and will be putting on the hks fcd, but it has the stock ecu at the moment. What is a safe amount of boost to run without changing the fueling/ecu? What turbo is fitted? The best advice would be to run NO boost until you have the fueling and ECU to support the single turbo conversion. The stock ECU can not 'safely' run a single turbo conversion. Edited December 4, 2015 by Nic (see edit history) Quote Link to comment Share on other sites More sharing options...
Milo500 Posted December 4, 2015 Author Share Posted December 4, 2015 What turbo is fitted? The best advice would be to run NO boost until you have the fueling and ECU to support the single turbo conversion. The stock ECU can not 'safely' run a single turbo conversion. Thats not what i was hoping for haha, heard standalone ecu's are around the 3k mark. If i ran the equivilent to what would be safe to run on the stock turbo's at bpu, or a slightly less, surely the stock fuel can keep up? Im just guessing though you guys are the pros. Is just a cheap garrett t4 ar/70 Quote Link to comment Share on other sites More sharing options...
np89 Posted December 4, 2015 Share Posted December 4, 2015 You can run a greddy emanage blue to compensate. Not ideal but it will do the job. Its about 300quid. Then whatever it is to fit and map Quote Link to comment Share on other sites More sharing options...
listy Posted December 4, 2015 Share Posted December 4, 2015 You'd be looking at £3k for a Syvecs or an ecu like that. You can pick plenty up for less than £1k, or piggybacks for £250-£500. Best thing to do is find out which ecu brand your "local mapper" specialises with and go down that route. As has been said, without an aftermarket piggyback ecu (at a minimum) of some kind, to control fuelling etc, you cannot safely run a single turbo conversion on a stock ecu. Quote Link to comment Share on other sites More sharing options...
Nic Posted December 4, 2015 Share Posted December 4, 2015 Thats not what i was hoping for haha, heard standalone ecu's are around the 3k mark. If i ran the equivilent to what would be safe to run on the stock turbo's at bpu, or a slightly less, surely the stock fuel can keep up? Im just guessing though you guys are the pros. Is just a cheap garrett t4 ar/70 Yes the stock fuel system is a big limiting factor to how much air you can safely squeeze into the engine. Think air flow, not boost pressure, at a given boost pressure a large turbo will force more air into the engine than a small turbo, which is why asking what boost pressure you can safely run without knowing what turbo is fitted is impossible to answer. The main issue though is the stock ECU, which is mapped to run 2 small sequential turbos, not one large single turbo. It may run but you will have no idea what the air/fuel mixture and timing are doing and there is a very big chance that you will trash the engine. At the very least you need a piggyback ECU fitting and mapping, it's not ideal but it should give you some control over the fueling and timing and you'll know just how much boost pressure you can safely run. If it was my car I'd remove the cheap single turbo kit, fit a set of stock turbos and enjoy the car. Quote Link to comment Share on other sites More sharing options...
Mike2JZ Posted December 4, 2015 Share Posted December 4, 2015 Why isn't it safe to run single on a TT ecu. So long as you aren't pushing loads of boost and your afr is in check thought it would be safe enough, just not an ideal setup Quote Link to comment Share on other sites More sharing options...
Mk4Gaz Posted December 4, 2015 Share Posted December 4, 2015 Why isn't it safe to run single on a TT ecu. So long as you aren't pushing loads of boost and your afr is in check thought it would be safe enough, just not an ideal setup It's to do with cfm, flow rates. A single turbo has the potential to flow far more air, than the stock twins. With more air, you need more fuel, which the stock setup may not be able to provide. Also, he hasn't mentioned what fuel pump, and pressure he's running. If it's a stock unit, I'd suggest changing it, as it could also be worn. Personally, I wouldn't risk it, and I certainly wouldn't take a guess at what a 'safe' boost level would be. At the very least, it would be worth paying for some dyno time, to monitor how it runs - using a wideband, and set of det cans. But, I would urge the op to consider investing in some form of after market management, that can be tweaked to suit his setup. Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted December 4, 2015 Share Posted December 4, 2015 First you need the flow map for the turbo if you can find it, but as said its not the boost pressure you need to worry about, the lager turbo will undoubtedly flow much more air than the std setup, and you don't yet know how much, the std ECU timing and fuelling maps will be quite different from what will be needed to run a single, despite the US bods saying you can run a small single on the TT ECU, I would suspect that there will be some rather gaping holes in the mapping. If you don't have a wide band lambda setup fitted I would not run any boost at all, as you have no idea how lean it may run. Quote Link to comment Share on other sites More sharing options...
Milo500 Posted December 4, 2015 Author Share Posted December 4, 2015 (edited) Im pretty sure i've got a stock j spec fueling system, i think the guy who had it before me was a bit of a doughnut and did the single turbo conversion and did nothing with fueling, had no boost controller, blocked off the wastgate hole (with no waste gate) no fuel cut defender etc etc. (Suprised he didn't ruin a 40,000 mile 2j) It now has a boost controller, proper wg setup, fcd is in, but has stock ecu's and i suspect stock fuel. I have bottomed out the greddy profec bc and is running 16 psi at a minium under full throttle...i never put my foot down due to obvious reasons, just once to get that reading earlier. Driving the car normally without booting it should be fine to drive right? It doesn't have a wideband, but i had a narrow afr gauge lying around, and just wired it in to get the basic, lean, normal, or rich reading...ofcourse it bounces all over the place on idle i know, but under full throttle it reads rich with no jumping to normal or lean...i know i don't know by how much, but is definitely reading rich Edited December 4, 2015 by Milo500 (see edit history) Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted December 5, 2015 Share Posted December 5, 2015 I would disable boost until you can equip the car to run the bigger turbo properly, I wouldn't trust a narrow band gauge to be accurate during boost even if it does say rich, it could well be running lean during part throttle, you say you take it easy but 16psi is not easy! you have been given plenty of sound advice regarding this, but you seem determined to drive it so its your car and your bill when it goes bang. Quote Link to comment Share on other sites More sharing options...
Ian C Posted December 5, 2015 Share Posted December 5, 2015 A narrowband reports 13:1 AFRs as "rich" so yeah... Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted December 5, 2015 Share Posted December 5, 2015 A narrowband reports 13:1 AFRs as "rich" so yeah... I am trying to guess if you have stayed up late, or got up early.... Without a deeper insight into how a stock TT ecu is mapped than I have ever seen published one has to assume running a turbo with totally different air density at a given RPM range to the stock sequentials will result in either some or all of its on boost running being outside the maps and into some sort of fail-safe region. It's so far from ideal I wouldn't even contemplate it myself, or recommend it to others, but people in the USA apparently do it. I have never been able to steel myself to go on the US Supra forums again after the first smell of the BS hit me though! Quote Link to comment Share on other sites More sharing options...
Milo500 Posted December 5, 2015 Author Share Posted December 5, 2015 Im not driving it on 16psi, that was just to get the figure to see how low it was running once. When driving it im not boosting it at all. How do you go about "disabling" the boost? As i've allready bottomed out the boost controller Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted December 5, 2015 Share Posted December 5, 2015 You can't "disable" the boost altogether, the wastegate spring and exhaust back pressure level is the limit of how low it can get. A VERY weak wastegate spring would lower it more. Quote Link to comment Share on other sites More sharing options...
Milo500 Posted December 5, 2015 Author Share Posted December 5, 2015 Just did an old school check of checking the spark plugs (as i don't have a wideband) just to see what is going on, and annoyingly all 6 plugs look completely perfect, no white residue on the electrode :/ so I'm not sure. I know it's supposed to be running stupidly lean. Quote Link to comment Share on other sites More sharing options...
a98pmalcolm Posted December 5, 2015 Share Posted December 5, 2015 Hi mate. I wouldn't use the car at all.. Until the below mods are sorted 1. Bigger fuel pump, about 400lph 2. Bigger injectors(I have some perfect 650cc SARD one for sale that fit the OEM fuel rail) 3. After market ECU, I'd recommend Syvecs These are essential. Don't waste money on the FCD as you wont need one with an after market ECU Big single turbo turbo kits aren't just a bolt on ans drive job, I wish they were. If you under fuel you could melt a piston or something Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted December 5, 2015 Share Posted December 5, 2015 [ATTACH=CONFIG]207289[/ATTACH] Just did an old school check of checking the spark plugs (as i don't have a wideband) just to see what is going on, and annoyingly all 6 plugs look completely perfect, no white residue on the electrode :/ so I'm not sure. I know it's supposed to be running stupidly lean. Old School plug check is useless unless you cut the motor at the RPM/load that you want to check, otherwise if it idles you just see the idle fueling. they do retain an impression of the average fueling and that plug looks decidedly grey...so yes its weak IMO. Quote Link to comment Share on other sites More sharing options...
Ian C Posted December 5, 2015 Share Posted December 5, 2015 I am trying to guess if you have stayed up late, or got up early.... Technically staying up late, but really just past lunchtime - I'm on nightshift What most people forget/don't realise/cross their fingers and hope it goes away, is that below 4000rpm the stock fuelling runs at 13:1AFRs on boost by design, as it's only on the first tiddler of a turbo. Stick a big single on and get a decent bit of load on the engine in a higher gear and you'll det the nuts off it below 4000rpm. Quote Link to comment Share on other sites More sharing options...
Milo500 Posted December 6, 2015 Author Share Posted December 6, 2015 Hi, Will be ordering a walbro fp and a greddy emanage piggyback for the time being I don't see how larger injectors are needed when im not running anywhere near the power that max out the stock injectors, won't be going anywhere above 450 because of the trans anyway. Thanks for the help guys but when people say don't drive it at all, isn't what IanC correct? Surely the standard map will be running more than enough fuel down the bottom end of the rev range to drive normally with no boost? Im not trying to go against what people have said, as im very appreciative of the sound advice, but at the moment this car is my daily as my capri is off the road. If if not spooling the turbo at all, is it nkt safe to drive? Quote Link to comment Share on other sites More sharing options...
mellonman Posted December 6, 2015 Share Posted December 6, 2015 (edited) Mate LeeP has a aem fic 8 for sale, it not a stand alone ecu its apiggy back and utilizes the stock ecu and sensors, I have been running one on my sigle turbo tt with a T67 turbo for over 4 years now , there is a few bugs to work out in regards to the ecu and firmware to run a supra but I have got over all that and could send you over a base map which would sort all the annoying stuff out and all you would have to do is have it tweaked to suit your turbo and set up. Your still going to need bigger injectors though if your aiming for more then 550bhp then you should go for bigger then 650 injectors to have some head room. I also have a auto and its been taking 524bhp with 510ftlb for that time also , im a strong believer that piggy back is the best way for longevity of the auto box , many that run standalone fail within a year Edited December 6, 2015 by mellonman (see edit history) Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.