viper Posted June 6, 2013 Share Posted June 6, 2013 Iv just heard from Thor racing that they have finally manged to map the car but the PI 3600 Hi stall will not lock out. Can anyone shead some light on this as iv had the gearbox refurbished and the oil changed several times now thinking that was the case. WHen should it lock out? or does it never lock out? Quote Link to comment Share on other sites More sharing options...
Kaan W Posted June 6, 2013 Share Posted June 6, 2013 What ecu(s) are you using? Are you getting manual mode and overdrive? It never locks out completely as if it was welded together as one unit and even past the rated stall speed a converter is always slipping, more so on higher stalls bearing in mind they will sacrafice top end power too but it all depends what ecu is controlling the box and how strong the signals are telling it to lock up etc. Quote Link to comment Share on other sites More sharing options...
viper Posted June 6, 2013 Author Share Posted June 6, 2013 Ah interesting, I'm running a piggyback MAP1 ecu so the box is being controlled by the stock ecu, no nothing happens when I press manual Quote Link to comment Share on other sites More sharing options...
Kaan W Posted June 6, 2013 Share Posted June 6, 2013 Hmm strange my Manu mode doesnt work either which makes it a real pita to dyno. To give you an idea my car was mapped at 1.6bar and produced 580hp on the stock converter, after fitting the 3800 high stall I had it mapped again increasing the boost to 1.8bar and I lost 40hp. Quote Link to comment Share on other sites More sharing options...
viper Posted June 6, 2013 Author Share Posted June 6, 2013 i guess that seems about right mine was mapped at 1.4bar and has 540hp (flywheel) apparently with 700ftlb Torque, but the wheel to engine rev ratio was down showing the TC hadnt locked out. Have read this on PI website it states: There is a misconception and a lot of misinformation about the poor vehicle performance numbers that are generated by testing a car with a high stall torque converter on a dynamometer. Most people that are not familiar with how a torque converter operates will automatically think that the torque converter is inefficient. This is totally false and the following facts are why you should not believe the dynamometer numbers while using an unlocked high stall torque converter. All late model dynamometers have a software program that commands the loading and speed of the vehicle over a certain period of time while making a test pull. The software used in these dynamometers is setup to be used with a locked 1:1 connection between the engine and the rear wheels, such as using a standard shift transmission in 3rd gear or when an automatic transmission has the torque converter clutch locked. When an unlocked high stall torque converter is used to make the pull and the dynamometer software has not been changed to allow for the fluid coupling differences the dynamometer readings will all be bogus. For instance, the low rpm torque readings will be high due to the torque multiplication of the torque converter being run in partial stall. Likewise, the high rpm torque readings will be low due to the long period of time the dynamometer takes to allow the torque converter to transition from partial torque multiplication to a hydraulic locked condition. The only cure for this phenomenon is to rewrite the dynamometer software to prevent this from happening. Torque converters with a low STR or low stall are not as adversely affected by this phenomenon. The high rpm transition problems never occur when the vehicle is being driven or raced normally. Therefore, worrying about what the dynamometer numbers are is a total waste of time. If your dynamometer operator refuses to alter the software to give correct readings then the only things you can do is (1.) lock the torque converter clutch and do the testing, (2.) use the readings you get with an unlocked torque converter as a baseline and continue to tune the car like normal until you get the best numbers remembering these are just numbers and not the actual horsepower and torque or (3.) use a dynamometer shop that gives you the service you deserve for your hard earned money. The only really true test of the performance of a vehicle is to take it to the track and see what ET and MPH the car will run. Quote Link to comment Share on other sites More sharing options...
Kaan W Posted June 6, 2013 Share Posted June 6, 2013 (edited) I'll read that in a sec, have you got a picture of the dyno graph and i'll post mine up to see how they compare in relation to torque multiplication? I have a feeling they look pretty simular... Edit: Good read that, that pretty much explains everything except why Manu mode doesnt work when piggy back ECU's are fitted? Edited June 6, 2013 by Kaan W (see edit history) Quote Link to comment Share on other sites More sharing options...
viper Posted June 6, 2013 Author Share Posted June 6, 2013 hub dyno all wheel figures on print out Quote Link to comment Share on other sites More sharing options...
Kaan W Posted June 6, 2013 Share Posted June 6, 2013 Kind of simular, as you can see it was quite a pain to achieve a decent reading, these are flywheel figures btw.. Im confused as to why manual mode doesnt work, has your mapper ever explained why manual mode cant work with piggypacks? Quote Link to comment Share on other sites More sharing options...
viper Posted June 6, 2013 Author Share Posted June 6, 2013 Yeah very similar, I have no idea why manual won't work, I converted from manual to auto as I'm purely dragging it so wanted the hi stall so iv no idea how the manual mode is sposed to work anyway Quote Link to comment Share on other sites More sharing options...
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