UK Supra TT Posted July 2, 2008 Share Posted July 2, 2008 Hi all, I've decided to replace my dead single turbo (an XS power T70, which seemed, besides the lag, pretty good until it went bang a month after fitting, but i'm not naive enough not to have been expecting that! lol Anyway, i've decided to replace it with a Garrett GT35R, a few guys running supra's seem to use these and like them, my old turbo was oil cooled, this has oil and water, I presume I take the water feed from the feed on the left side of the top rad pipe, where the stock turbo's got there's? and it returns to the metal pipe about mid way down the engine at the back? What dash size hose do people run for water on these things, I was planning on using an aeroquip braided hose. My next question is on tunning the AFR, some people seem to suggest tunning for lambda 1 (14.7 stoich) throughout the RPM range, others say more like high 12's, i'm a bit worried about this since I don't want to run the car lean and push up the EGT, any fuel experts out there? Cheers guys Link to comment Share on other sites More sharing options...
Wez Posted July 2, 2008 Share Posted July 2, 2008 Get it mapped by a proper mapper. If you are asking about what AFRs to run you shouldnt be mapping it plus I would disregard anything the guys says who recommended 14.7 for the whole rev range on a turbo car, I assume you made it clear about the higher load sites (being turbo) and not atmospheric and cruise/vac. Link to comment Share on other sites More sharing options...
steb9780 Posted July 2, 2008 Share Posted July 2, 2008 I thought 14.7ish on idle was the norm, and at WOT it should be in the low 11's, around 11.3 I think. I can't remember the exact figure for WOT, somebody will be along though shortly who knows the exact figures Link to comment Share on other sites More sharing options...
steb9780 Posted July 2, 2008 Share Posted July 2, 2008 I thought 14.7ish on idle was the norm, and at WOT it should be in the low 11's, around 11.3 I think. I can't remember the exact figure for WOT, somebody will be along though shortly who knows the exact figures Wez beat me too it Link to comment Share on other sites More sharing options...
UK Supra TT Posted July 2, 2008 Author Share Posted July 2, 2008 It's all well and good just getting it mapped by someone else but I'm trying to learn, i'm sorry if I seem I don't know what i'm talking about like you guys but isn't that all part of learning surly?? I'm not just going to rush in there and fiddle, I want to learn, I'm not the sort of person how is happy just to palm off anything there not sure about, I want to know how it works myself. Why does your AFR change so mush under high loads? surly the air/fuel ratio measured in the exhaust should show an "optimum" burn throughout the RPM range regardless of boost pressure and load, surly if you burn fuel weather its combined with atmospheric pressure air or compressed you still want it to burn properly and efficiently, and isn't that what your finding out by looking at your lambda reading? I apologies if my questions seem stupid, but like I said i'm just interested in learning, if i don't manage to grasp it i will get someone else to map the car. Link to comment Share on other sites More sharing options...
Homer Posted July 2, 2008 Share Posted July 2, 2008 If you're asking these sort of questions, then seriously don't even think about mapping it. Mapping is MUCH more complex than just looking an an AFR gauge! If you do want to make a start then a few here can recommend some books and courses to begin with. If you make a mistake or your AFR gauge is slightly out you'll be looking at a new engine. Can you really afford that for the sake of paying £200 for a profesional to do it? Regarding the water pipes, the flow is the other way round, the feed should come from the water pump and to a T to the rear stock line, the return is into the water elbow. Link to comment Share on other sites More sharing options...
Wez Posted July 2, 2008 Share Posted July 2, 2008 I apologies if my questions seem stupid, but like I said i'm just interested in learning, if i don't manage to grasp it i will get someone else to map the car. I appreciate you are trying to learn which is great but as already mentioned its not as simple as just setting up your AFR. If you get it wrong you will blow your engine. Link to comment Share on other sites More sharing options...
Ian C Posted July 2, 2008 Share Posted July 2, 2008 Why does your AFR change so mush under high loads? surly the air/fuel ratio measured in the exhaust should show an "optimum" burn throughout the RPM range regardless of boost pressure and load, surly if you burn fuel weather its combined with atmospheric pressure air or compressed you still want it to burn properly and efficiently, and isn't that what your finding out by looking at your lambda reading? Corky Bell, Maximum Boost. Buy it and read it, if you are actually interested in the subject you'll probably read it at least twice There is also some stuff to learn about heat management and the role fuel mixtures play in that, and your ignition timing too which an AFR gauge can't help you with. And NA power, and throttle tip-in enrichment and so on and so forth. Membership cheque in the post is it? -Ian Link to comment Share on other sites More sharing options...
UK Supra TT Posted July 2, 2008 Author Share Posted July 2, 2008 Thanks for the input guys, have you got any books you can suggest, are there courses in such things? I always assumed it was more of an apprenticeship kind of thing, although I know innovate motorsport run courses in the states, anyone know of a UK equivalent? I appreciate its not as simple as looking at the AFR I'm just trying to work out the relationship between TPS, MAP, EGT, AFR, ignition, etc That the other side of it too the ignition timing, and i know if you adjust one it has a knock on effect to fueling etc. I probably went about asking the wrong way and gave the impression I was about to jump in and throw some figures in, however I presume since at the moment i'm running a piggy back ecu (emanage) the stock ecu will still be doing most of the complex stuff and i'd just be offsetting the values to compensate for larger injectors, different turbo etc? Link to comment Share on other sites More sharing options...
UK Supra TT Posted July 2, 2008 Author Share Posted July 2, 2008 Thanks Ian, i'll have a look for that book, sounds good! To be honest I didn't even relies there was a membership fee, don't come on here often, just noticed that notice under my name though on the left, how does that work, is it a yearly fee or something, who do i talk to about it? Link to comment Share on other sites More sharing options...
UK Supra TT Posted July 2, 2008 Author Share Posted July 2, 2008 Is this the book? http://cgi.ebay.co.uk/Maximum-Boost-Designing-Testing-I-Bell-Corky_W0QQitemZ330248162320QQcmdZViewItem?hash=item330248162320&_trkparms=72%3A12%7C39%3A1%7C65%3A12&_trksid=p3286.c0.m14 Link to comment Share on other sites More sharing options...
UK Supra TT Posted July 2, 2008 Author Share Posted July 2, 2008 Oh by the by while i've got all you technical bods here, do you know what kind of frequency band knock occures in teh 2JZ-GTE engine? i know knock can occure between 6-9KHz but i'm designing my own Fourier transform analysis device, using a microcontroller, knock monitoring seems to be really expensive so though it would be interesting to make my own Link to comment Share on other sites More sharing options...
Wez Posted July 2, 2008 Share Posted July 2, 2008 knock monitoring seems to be really expensive so though it would be interesting to make my own What is the purpose of your device, is it visual like this unit :- http://www.phormula.co.uk/KnockDetection-KS-3.aspx Link to comment Share on other sites More sharing options...
UK Supra TT Posted July 2, 2008 Author Share Posted July 2, 2008 Yeah basically, more of a graphical LCD display though showing effectively a spectrum analyzer, knock can then be seen clearly at specific frequencies in the graph, but I'd imaging each engine type knocks at fairly specific frequencies due to the construction, resonance etc. That one is pretty well prices though isn't it Link to comment Share on other sites More sharing options...
Wez Posted July 2, 2008 Share Posted July 2, 2008 That one is pretty well prices though isn't it Yep, they also make this knock box which is nice and can be linked to the above screen. http://www.phormula.co.uk/KnockAnalyserPro.aspx If you are serious about mapping then you should invest in something like this or a KnockBox. Here is the complete kit from Phormula :- http://www.phormula.co.uk/ProTuningSolution.aspx Link to comment Share on other sites More sharing options...
UK Supra TT Posted July 2, 2008 Author Share Posted July 2, 2008 Yeah but like I said i'm going to make my own, at the end of the day knock is just a vibration picked up by the knock sensor (effectively a microphone) the "knock analyzers" out there are just a band pass amplifier to a set of head phones, and the display types, if there any good, are a Fourier transform analyzer which just show you the number of spikes at a specified frequency over a specified threshold Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted July 2, 2008 Share Posted July 2, 2008 Knock on the TT engine occurs at 6.6 MHz so anywhere between 6.4 and 6.7 should cover it, i will say if your going to make your own, use a new Bosch widband sensor as per the Phormula set up, which i have and find very good, as it has an alarm for knock alert, you try keeping an eye on all the gauge's etc while doing a high load pull:blink: As said don't even attempt mapping until you have a good understanding of all the processes, and have all the relevant feedback devices/data logging. Link to comment Share on other sites More sharing options...
Ian C Posted July 2, 2008 Share Posted July 2, 2008 and have all the relevant feedback devices/data logging. Especially for individual cylinder trimming Link to comment Share on other sites More sharing options...
Chris Wilson Posted July 2, 2008 Share Posted July 2, 2008 If you want to experiment with mapping an ecu start on an N/A engine of little monetary value. Once you are happy ith mapping ignition and fuelling on an N/A move onto a basic turbo engine, which is a LOT more complex to map. There are courses, Motec have them, possibly other ecu makers too. I have yet to read a GOOD book on how to map, it's very much something that you pick up with experience, but the errors you can make could be expensive! I'd have a go mapping an N/A, but not a turbo engine unless it was sacrificial Link to comment Share on other sites More sharing options...
T2 MSW Posted July 2, 2008 Share Posted July 2, 2008 If you make a mistake or your AFR gauge is slightly out you'll be looking at a new engine. Can you really afford that for the sake of paying £200 for a profesional to do it? £200?, you need to share where you get your mapping done!! Link to comment Share on other sites More sharing options...
Chris Wilson Posted July 2, 2008 Share Posted July 2, 2008 £1000 a day is more realistic, IMO. Link to comment Share on other sites More sharing options...
Homer Posted July 2, 2008 Share Posted July 2, 2008 £1000 a day is more realistic, IMO. Engine dyno? Otherwise Ryan isn't charging enough Link to comment Share on other sites More sharing options...
Wez Posted July 2, 2008 Share Posted July 2, 2008 £1000 a day is more realistic, IMO. Link to comment Share on other sites More sharing options...
Chris Wilson Posted July 2, 2008 Share Posted July 2, 2008 Yep, current dyno time, with oils, fuel and stuff is circa a grand a day, sometimes more. Add in making any adaptors and the price can rise higher. At least on the dyno you can address leaks, tweak cam timing and control temps to map for out of the ordinary air and water temps accurately. Soul destroying pulling an engine to fix some inaccessible leak,or whatever. Link to comment Share on other sites More sharing options...
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