Vaughany Posted July 15, 2005 Share Posted July 15, 2005 I have just had a PHR Stage 1 kit (similar to Boost Logic T61) fitted that is running and has been mapped at a maximum of 1.4bar. My question is can I raise the boost to say 1.5/1.6bar on Optimax or is this to high for 98 octane fuel. My fuelling is spot on at 1.4bar and also have water injection that will help prevent detonation and keep temps down. Also i suppose I could add an octane booster when I want to run more than 1.4bar. The car is awesome at 1.4bar but was wandering if I could run higher boost on occasion. My Supra is an Auto so the transmission is probably handling all it can but I have added a transmission cooler to help keep the fluid cooler. What is everyone else running on a Single Turbo with 98 octane fuel? Quote Link to comment Share on other sites More sharing options...
JohnA Posted July 15, 2005 Share Posted July 15, 2005 Can you find the compressor map for the turbo mate? Quote Link to comment Share on other sites More sharing options...
Vaughany Posted July 15, 2005 Author Share Posted July 15, 2005 Please explain mate as I do not know what you mean Quote Link to comment Share on other sites More sharing options...
JohnA Posted July 15, 2005 Share Posted July 15, 2005 It's a diagram that sometimes is available for aftermarket turbos. It is very helpful in deciding how far you can push a turbo on a specific engine (among others) Quote Link to comment Share on other sites More sharing options...
Vaughany Posted July 15, 2005 Author Share Posted July 15, 2005 Hello Mate, the link on MVP states that the turbo is rated for 2bar and has been driven at this on a Supra. My issue is rather, what is the maximum boost you can run on a given octane. Quote Link to comment Share on other sites More sharing options...
JohnA Posted July 15, 2005 Share Posted July 15, 2005 It's not cut'n'shut. Depends on compression ratio, ignition timing, cam timing, intercooling and others (and that's just for engine durability) To decide for the turbo itself one would need to look at the compressor map, or else would be guesswork... [30psi boost is quite a stretch for most turbos, even if you run race fuel and manage to avoid detonation in the engine] Quote Link to comment Share on other sites More sharing options...
Vaughany Posted July 15, 2005 Author Share Posted July 15, 2005 Cheers John, guess I am staying at 1.4 for now then. Quote Link to comment Share on other sites More sharing options...
JohnA Posted July 15, 2005 Share Posted July 15, 2005 In very general terms, the engine will be much happier at 1.4 bar from a 'lagre' turbo like yours compared to 1.4bar on stocks. But this really is a very general statement. Quote Link to comment Share on other sites More sharing options...
Guest Usmann A Posted July 15, 2005 Share Posted July 15, 2005 youd have to roughly work out howmuch CFM the motor would flow at your chosen boost level, and then look at the pressure ratio you intend to runm and see in what sort off effieincy % the compressor runs at? its mostly all guess work as to REALLY work out howmuch CFM the motor ingests we start talking about long long calcs ... and VE, which some of the AEM guys can get by just looking at thier fuel tables ... Anyway, if you need to convert CFM to lb/min its CFM*.76(at sea level) to give you a =lb/min. its roughly like this ... 183 cid/1728= .1059 cubic feet of displacement 7100 rpm /2 = 3550 cylces per min 3550 cycles* .1059 = 375.94 CFM 375.94* 99%VE = 372 CFM to get Pr(pressure ratio), gauge boost+14.7/14.7 = pressure ratio. I hope this helps you understand when looking at comp maps, although ive left out loads of variables, like temp rise,boost,adiabatic effic,IC eff,density ratio, etc ,etc. but to get those all correct and in real time is something im working on. HTH Quote Link to comment Share on other sites More sharing options...
JohnA Posted July 15, 2005 Share Posted July 15, 2005 ....all very nice and well, but of limited usefulness without the compressor map, eh? Quote Link to comment Share on other sites More sharing options...
Guest Usmann A Posted July 15, 2005 Share Posted July 15, 2005 mm, John, that is the info needed to look at any comp map. ROUGHLY Its good to know:) I thought id explain to our dear member"Vaughny" on how comp maps work, very simple. its a tech section, and info is taken and given. I expect that little post to be on your website, along with the collection of other peoples stuff. May I call you copy and past king from now on John. Quote Link to comment Share on other sites More sharing options...
JohnA Posted July 15, 2005 Share Posted July 15, 2005 I expect that little post to be on your website, not really, why would you think that I'd copy your post and pass it as mine? (or whatever?) If I feel the need to explain these things I can do it myself, can't I? ...along with the collection of other peoples stuff. I do have lots of links to whatever I see as relevant or interesting. That's the whole idea of the internet, we don't need to reivent the wheel May I call you copy and past king from now on John. Not really, if you think that I created my site using cut and paste you are grossly mistaken mate. If text was taken from another source it's always credited (if it cannot be linked) and usually it's in different font/colour. Quote Link to comment Share on other sites More sharing options...
Guest Usmann A Posted July 15, 2005 Share Posted July 15, 2005 lighten up John, its not nice when someone starts to bitch is it#? I suggest you come off your high horse,as your atitiude simply comes across rather appauling sometimes,I didnt like the way in which you answered my post,it wasnt aimed at you. So, who are you to question it? Ive seen you post countless times on stuff not appilcable, but I dont go out my way to say, "oooo this, ooo that". Evethough you being my senior, I suggest you grow up stop playing grandad "know it all " of the BBS. You are not the only one that knows about tuning, I see you have conflict with nearly everyone of the techies on this site. I wonder why. Now have fun ... ..... I know I will .... Quote Link to comment Share on other sites More sharing options...
JohnA Posted July 15, 2005 Share Posted July 15, 2005 I suggest you come off your high horse what high horse dude, are you for real? ..as your atitiude simply comes across rather appauling sometimes, well if I propose to you, don't marry me Evethough you being my senior, I suggest you grow up stop playing grandad "know it all " of the BBS. I don't know it all mate. If I did I wouldn't need to be here and learn from others. I know that my internet 'persona' is kinda annoying sometimes, I can't help it though. It's not how people find me face to face - I blame the faceless internet . That's why I added the last bit in my signature to account for this . Quote Link to comment Share on other sites More sharing options...
Vaughany Posted July 15, 2005 Author Share Posted July 15, 2005 Gentlemen, I thank you both for your info and expertise. My knowledge is not that in-depth so I think I read up a bit more and try to collate a variety of opinions. In simple terms, I was hoping that someone would be able to say yes you can, no you cant and even better than that actually give examples based on their own experience. I feel my mods cover everything safety wise but I am not sure. For example I have PHR Stage 1 Kit HKS Type R Intercooler Mocal Oil Cooler Mocal Transmission cooler 650cc Injectors and all other main stream fuelling mods Water Injection I apologise for my ignorance but I thought it was to do with the octane rating hence everyone uses race fuel when they are running very high boost. Anyway, thanks again now please CHILL OUT! Quote Link to comment Share on other sites More sharing options...
b_have Posted July 15, 2005 Share Posted July 15, 2005 Woooah! Guys, c'mon! You two are both very knowledgable guys, I read all your tech posts with great interest. Not interested in the ego battles! Quote Link to comment Share on other sites More sharing options...
Guest Usmann A Posted July 15, 2005 Share Posted July 15, 2005 well, I don trun more than 17 psi on my 74, on 93USmon fuel(optimax) on moderate timing. Sorry for the drama. edited, i noticed its a 61mm, if so then I know guys running 1.6 bar, but thier using methanol, and fully mappable EMSs. I cant comment on personal experience, but I know friends of mine who run 61s at around 1.3+ bar on pump fuel ... anything over 1.7 and I think it gets out of its ideal efficiency range ... but id need a comp map to check that.LOL ive got all of PTEs comp maps on my laptop which is not with me, but if no one can get you it by monday, ill post it up. Quote Link to comment Share on other sites More sharing options...
Vaughany Posted July 15, 2005 Author Share Posted July 15, 2005 Hello B'have I noticed you are running te same kit as myself, what boost pressure are you running and have you had he car dynoed. Just interested to see what results you have had. Usmann A - I am fairly sure the stage 1 is a GT60 Quote Link to comment Share on other sites More sharing options...
b_have Posted July 15, 2005 Share Posted July 15, 2005 well, I don trun more than 17 psi on my 74, on 93USmon fuel(optimax) on moderate timing. Sorry for the drama. PHR stage 1 is a GT67 right? if so, and it runs a .81hotside, ive got comp maps for that on my PC somewhere, let me dig them out. even if not, you'll be fine for running over 1.5 bar easy pesy on a 67mm. Yeeeeeeees! thats great (as I have a T61!) Quote Link to comment Share on other sites More sharing options...
Guest Usmann A Posted July 15, 2005 Share Posted July 15, 2005 all edited now guys, I dont know what PHR class thier turbos at, just when I saw Bhaves sig, I realised...... Quote Link to comment Share on other sites More sharing options...
b_have Posted July 15, 2005 Share Posted July 15, 2005 Hello B'have I noticed you are running te same kit as myself, what boost pressure are you running and have you had he car dynoed. Just interested to see what results you have had. Usmann A - I am fairly sure the stage 1 is a GT60 Hi Vaughany, yes, fitted the PHR kit 3 years ago. Im not going above 1.5 at the mo as the SAFC is maxing out on 550 inj+FSE @ 40psi static. Have some 650's here for when i go e-mange ultimate or motec Quote Link to comment Share on other sites More sharing options...
Vaughany Posted July 15, 2005 Author Share Posted July 15, 2005 Hello Mate, I noticed your sig states 103 race fuel, is this what you are running at 1.5Bar. I am currently running a maximum of 1.4bar on 650cc with Emanage and my Dyno Graph shows my fuelling as spot on. I was going to increase the boost a bit and use the water injection to compensate so I dont get any det but I was unsure if this is safe on 98octane. Supraforums had a thread stating safe boost pressures on certain grades of fuel but unfortunately all there numbers seem to be different and they are quoting RON etc. Quote Link to comment Share on other sites More sharing options...
JohnA Posted July 16, 2005 Share Posted July 16, 2005 I was going to increase the boost a bit and use the water injection to compensate so I dont get any det but I was unsure if this is safe on 98octane. You can run silly boost pressures on SUL if water injection is set up accordingly, but I wouldn't exactly call it 'safe' You're playing with fire, any failure in the W.I. circuit will end up in tears. At the very least you'd need a flowmeter (Aquamist do one that acts as a sensor - produces 0-5V depending on fluid flow) Supraforums had a thread stating safe boost pressures on certain grades of fuel but unfortunately all there numbers seem to be different and they are quoting RON etc. I've seen it, and frankly can't think how it can really be of any use. There are so many variables involved that it is meaningless if you haven't got the same setup as it assumes. You'd need knock monitoring if you start pushing the envelope towards DetLand. [ Quote Link to comment Share on other sites More sharing options...
Ian C Posted July 16, 2005 Share Posted July 16, 2005 Vaughney - it varies slightly from setup to setup mate. Some people can't run more than 1.4bar, some people can, but probably not *much* more. Intercooling is a big factor as well as octane, and compressor efficiency at that CFM flow (not *quite* boost pressure as it takes engine speed into account, thanks for the earlier explanation Usmann) as these are all factors in keeping the charge temps down to stave off det. I know a T61 that detted at 1.4bar and needed timing pulled to even stand a chance, even that was marginal and that's on a cold day with some moisture in the air! I also know a T67 that could run 1.4bar on a hot dry day with no timing pulled. However, if your car has been mapped for 1.4bar then I really wouldn't take it above that Your tuner will have monitored AFRs, and started off nice and rich and sorted the ignition timing out and be listening for det... Except they haven't done any of that for more than 1.4bar (well maybe a smidge more to allow for boost fluctuation). It may handle more boost in theory but it'd still need mapping to that boost level -Ian Quote Link to comment Share on other sites More sharing options...
Vaughany Posted July 16, 2005 Author Share Posted July 16, 2005 Thanks Guys - Ian are you still taking your Laptop to JAE? If possible and you have the time I would like you to download my current Emanage map. We have previously spoke about me bringing my Supra to you for tweaking? Are you there on Sunday? Quote Link to comment Share on other sites More sharing options...
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