needy Posted January 9, 2011 Share Posted January 9, 2011 I would like to know what your show at idle and normal driving. like responses from people whos cars running std TwinTurbo and front mounted intercooler. and what fuel pressure is recommended? Quote Link to comment Share on other sites More sharing options...
Homer Posted January 9, 2011 Share Posted January 9, 2011 AFR's should float between 14.0 and 15.0 on idle, it'll go up and down every 2 or 3 seconds as the engine constantly adjusts the fueling. That's the same for any supra regardless of mods. Fuel pressure should be left stock (33 to 38psi), though most with BPU mods and an adjustable FPR set it to 38 or 40 psi to help get that little bit extra fuel in. Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted January 9, 2011 Share Posted January 9, 2011 You forgot the normal driving bit Darryl, anything from the 14.7 down to the 10s on full boost, you will also see 20.9 or 00 on closed throttle deceleration, as the injectors don't fire on closed throttle. Quote Link to comment Share on other sites More sharing options...
needy Posted January 9, 2011 Author Share Posted January 9, 2011 ok. my air/fuel goes from 14.8 to 15.2 at idle, does that seems right.. i have a fuel pressure regulator and it lies at 40 to 44 psi do i have somthing to worry about? Quote Link to comment Share on other sites More sharing options...
needy Posted January 9, 2011 Author Share Posted January 9, 2011 i think at full throttle it goes about 10 til 10.5 as i reamember Quote Link to comment Share on other sites More sharing options...
Homer Posted January 9, 2011 Share Posted January 9, 2011 Whoops, missed the normal driving part. ok. my air/fuel goes from 14.8 to 15.2 at idle, does that seems right.. i have a fuel pressure regulator and it lies at 40 to 44 psi do i have somthing to worry about? Yes, that's normal. Have you checked the static pressure of the FPR? It needs to be done without the engine running but the fuel pump running, it won;t give a static reading with the engine running. i think at full throttle it goes about 10 til 10.5 as i reamember That sounds about right for stock, maybe a bit rich for BPU, what boost are you seeing? Remember AFR's need to be checked at various points during the rpm range, in particular at the transition point to ensure it's not running lean when the 2nd turbo comes online. Quote Link to comment Share on other sites More sharing options...
needy Posted January 9, 2011 Author Share Posted January 9, 2011 static pressure of the frp? can you explain it a little closer.. i am running std setup at boost. 0.9 bar.. Quote Link to comment Share on other sites More sharing options...
Terminator Posted January 9, 2011 Share Posted January 9, 2011 10 sounds very rich! Quote Link to comment Share on other sites More sharing options...
Homer Posted January 9, 2011 Share Posted January 9, 2011 static pressure of the frp? can you explain it a little closer.. i am running std setup at boost. 0.9 bar.. To get a static reading you need to have the engine off, but trick the ECU to running the fuel pump and fuel system at pressure. To do this, bridge +B and FP ports on the engine diagnosics port, then turn the ignition to II and take a reading from the fpr gauge For 0.9 bar a reading of 10.0 on full boost is very rich. What RPM is that at and in what gear? Also 0.9 is not stock, 0.76bar is stock. What modifications have been made? Are the exhaust and/or cats standard? Finally what boost gauge do you have and is it a mechanical or electrical one? Quote Link to comment Share on other sites More sharing options...
needy Posted January 9, 2011 Author Share Posted January 9, 2011 ok, i will trye that.. what should i read at the fuel pressure gauge? 3 and 4 gear at full throttle and 0.9 bar at the boost gauge Quote Link to comment Share on other sites More sharing options...
Homer Posted January 9, 2011 Share Posted January 9, 2011 ok, i will trye that.. what should i read at the fuel pressure gauge? 3 and 4 gear at full throttle and 0.9 bar at the boost gauge I'm not sure what you mean by what you should read at the FPR gauge - do you have an aftermarket FPR with a dial gauge attached? If not, where are you getting your fuel pressure reading from? Regarding the boost, please re-read my post and reply with your input, I edited after clicking reply. Quote Link to comment Share on other sites More sharing options...
needy Posted January 9, 2011 Author Share Posted January 9, 2011 i have another exhaust on the car, std cat. thats all.. i have an electrick boost gauge.. it is an aftermarket fuel pressure regulator located on the hose which is connected to the intake. and is set at the return hosewhich goes to to the fuel tank. and is adjusted to reflect 40 to 44 psi at idle. and it is mechanically. I still have the std fuel pressure regulator installed Quote Link to comment Share on other sites More sharing options...
Homer Posted January 9, 2011 Share Posted January 9, 2011 i have another exhaust on the car, std cat. thats all.. i have an electrick boost gauge.. it is an aftermarket fuel pressure regulator located on the hose which is connected to the intake. and is set at the return hosewhich goes to to the fuel tank. and is adjusted to reflect 40 to 44 psi at idle. and it is mechanically. I still have the std fuel pressure regulator installed The aftermarket exhaust may explain the increase in boost, do you have both cats still in place? The FPR sounds a little strange.. If the stock FPR is still in place there certainly shouldn't be anything else in the fuel line, particularly another FPR! An additional FPR will screw up the operation of the original one and can't change the fuel pressure, other than restrict it. Can you post a picture of it so we can try figure out what it is? It may just be a gauge (which shouldn't be there, even if intended) Quote Link to comment Share on other sites More sharing options...
Swampy442 Posted January 9, 2011 Share Posted January 9, 2011 and is adjusted to reflect 40 to 44 psi at idle. Thats too much pressure, it should indicate that with the engine off. Quote Link to comment Share on other sites More sharing options...
needy Posted January 9, 2011 Author Share Posted January 9, 2011 Thats too much pressure, it should indicate that with the engine off. it is with the engine running, it shows 40 to 44 psi on the fuel pressure regulator Quote Link to comment Share on other sites More sharing options...
Homer Posted January 9, 2011 Share Posted January 9, 2011 it is with the engine running, it shows 40 to 44 psi on the fuel pressure regulator The fuel pressure at the gauge will be lower with the engine running, which is why static pressure needs to be found. Quote Link to comment Share on other sites More sharing options...
bignum Posted January 9, 2011 Share Posted January 9, 2011 Probably why he`s running rich on wot. Quote Link to comment Share on other sites More sharing options...
Homer Posted January 10, 2011 Share Posted January 10, 2011 Probably why he`s running rich on wot. Yep, that's what I'm getting at Quote Link to comment Share on other sites More sharing options...
Swampy442 Posted January 10, 2011 Share Posted January 10, 2011 Think the best thing you can do is to run the fuel pump with the engine off, knock the fuel pressure back to about 38psi and see what happens Quote Link to comment Share on other sites More sharing options...
needy Posted January 10, 2011 Author Share Posted January 10, 2011 The fuel pressure at the gauge will be lower with the engine running, which is why static pressure needs to be found. then I tried b + og fp diagnostic connector. and it showed 60 psi with the engine off. has so adjusted fuel pressure down to 40 psi with the engine off, and started the engine then the fuel pressure shows 25 psi, but if i takes b + and fp with the engine on, it shows 38 psi, is it my aftermarket fuel pressure regulator which is defective? with running hot engine, the AFR shows 14.8 to 15 at idle now Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted January 10, 2011 Share Posted January 10, 2011 then I tried b + og fp diagnostic connector. and it showed 60 psi with the engine off. has so adjusted fuel pressure down to 40 psi with the engine off, and started the engine then the fuel pressure shows 25 psi, but if i takes b + and fp with the engine on, it shows 38 psi, is it my aftermarket fuel pressure regulator which is defective? with running hot engine, the AFR shows 14.8 to 15 at idle now Running two FPRs is not a good idea, and certainly not necessary on a BPU Supra, take one out, and if the the aftermarket one is a cheap type, thats the one that needs to go. Quote Link to comment Share on other sites More sharing options...
needy Posted January 10, 2011 Author Share Posted January 10, 2011 Running two FPRs is not a good idea, and certainly not necessary on a BPU Supra, take one out, and if the the aftermarket one is a cheap type, thats the one that needs to go. yes i have the original which sits at the fuel bridge, and the aftermarket which are connected by the return pipe to the tank. yes it aftermarket fuel pressure regulator is a cheap one off the kind.. Quote Link to comment Share on other sites More sharing options...
Homer Posted January 10, 2011 Share Posted January 10, 2011 Well 60psi is WAY to high, so ast least that is one thing partially resolved You need to get rid of it, you can't have two FPR's on a car or it could seriously screw up the fueling. I'm interested as to what's been done here, can you post a pic of it? Quote Link to comment Share on other sites More sharing options...
needy Posted January 10, 2011 Author Share Posted January 10, 2011 Well 60psi is WAY to high, so ast least that is one thing partially resolved You need to get rid of it, you can't have two FPR's on a car or it could seriously screw up the fueling. I'm interested as to what's been done here, can you post a pic of it? as I also tried to explain further up, then there is an original fuel pressure regulator which sits on the fuel bridge, and then I have the aftermarket fuel pressure regulator attached to the return page that goes to the tank, this shuld after signing give a higher pressure in fuel bridge .. hope you understand what I mean Quote Link to comment Share on other sites More sharing options...
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