costas1 Posted February 4, 2015 Share Posted February 4, 2015 i decided to take my bpu (3' exhaust hks 4' intercooler) j spec on the dyno yesterday after 5 years of driving with no issues..the car made 425hp on the wheels @1.2 bar but it hitted 14 afr on high boost(beyond 6000 rpm) and the tuner there said it was very dangerous and wonders how my engine did not explode all these years..so i am installing a wallbro 255lph for now..will that fix the problem a little bit? Quote Link to comment Share on other sites More sharing options...
mellonman Posted February 4, 2015 Share Posted February 4, 2015 I was just writing in your other thread but see this you seriously need that fuel pump fitted asap, I do expect if you have been running at that afr for some time you have done some serious damage to that engine, I expect its been detting all over the place, get a bore scope down a spark plug hole and see if there is piston damage Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted February 4, 2015 Share Posted February 4, 2015 Something not right there, the first being able to make 425BHP at the wheels on an AFR of 14??? it just wouldn't do it that would equate to around 460BHP at the fly...NEVR heard of that at BPU levels, especially with no ECU. And as said there would be serious engine damage, like I said there is something no right with the figures, try another dyno, and get a decent AFR gauge/wide band lambda fitted, also run a compression test. Quote Link to comment Share on other sites More sharing options...
costas1 Posted February 4, 2015 Author Share Posted February 4, 2015 if i had damaged the engine all these years would i not notice it by now..the car runs very smooth and sounds perfect all these years..and still pulls hard...i do not know..all i want to know is if the pump will help the situation.. I was just writing in your other thread but see this you seriously need that fuel pump fitted asap, I do expect if you have been running at that afr for some time you have done some serious damage to that engine, I expect its been detting all over the place, get a bore scope down a spark plug hole and see if there is piston damage Quote Link to comment Share on other sites More sharing options...
costas1 Posted February 4, 2015 Author Share Posted February 4, 2015 i also posted on the dyno section where you can see the graph of the dyno..i also have a EGT gauge in the car and if i am correct shows about 800 degrees celcious on full load..is that ok?.. what numbers should i expect to see for a healthy compression test? Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted February 4, 2015 Share Posted February 4, 2015 if i had damaged the engine all these years would i not notice it by now..the car runs very smooth and sounds perfect all these years..and still pulls hard...i do not know..all i want to know is if the pump will help the situation.. You need to do some investigation, test fuel pressure, like I said I seriously doubt any of those figures give, and in particular the AFR, throwing a fuel pump at it in the hope that it will fix it is wasting money, test first, then fit whats necessary. Quote Link to comment Share on other sites More sharing options...
costas1 Posted February 4, 2015 Author Share Posted February 4, 2015 the tuner at the dyno shop said that the car made more power cause it was running lean but its dangerous..he said that normaly the car should made 380 on on the wheels if the afr was correct...do not know..i am lost here..anw thx for the opinions Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted February 4, 2015 Share Posted February 4, 2015 i also posted on the dyno section where you can see the graph of the dyno..i also have a EGT gauge in the car and if i am correct shows about 800 degrees celcious on full load..is that ok?.. what numbers should i expect to see for a healthy compression test? 800c is quite low, and would also indicate that its not making anywhere near that sort of power in std trim, 900-950c is about the limit, compression wise you should see about 140- 160psi on a good healthy motor, but make sure you test with a fully charged battery, with all the plugs out, and the throttle plate fully open, and the engine turned the same number of times...at least 6. Quote Link to comment Share on other sites More sharing options...
Mk4Gaz Posted February 4, 2015 Share Posted February 4, 2015 I think the figures you're quoting are fwhp not whp. 380 fwhp is about right at 1.2 bar. If yours is 420, it's feasible with being that lean, but far from ideal Quote Link to comment Share on other sites More sharing options...
costas1 Posted February 4, 2015 Author Share Posted February 4, 2015 it was a dynojet dyno and it measures wheel horse power..for the afr he put a sensor at the end of the exhaust-muffler..thx tricky for the info Quote Link to comment Share on other sites More sharing options...
mellonman Posted February 4, 2015 Share Posted February 4, 2015 (edited) 800c is quite low, and would also indicate that its not making anywhere near that sort of power in std trim, 900-950c is about the limit, compression wise you should see about 140- 160psi on a good healthy motor, but make sure you test with a fully charged battery, with all the plugs out, and the throttle plate fully open, and the engine turned the same number of times...at least 6. Also depends where the egt sensor is also, being its stock tt I wonder where itis located? Have a look at his post in the dyno section with the print out looks pritty normal before full boost afr wise and leaning out considerably indicating fuel pump Edited February 4, 2015 by mellonman (see edit history) Quote Link to comment Share on other sites More sharing options...
costas1 Posted February 4, 2015 Author Share Posted February 4, 2015 the egt gauge is aftermarket and it was already installed when i bought the car..i think the sensor is located at the second decat if i am not mistaken.. Quote Link to comment Share on other sites More sharing options...
mellonman Posted February 4, 2015 Share Posted February 4, 2015 the egt gauge is aftermarket and it was already installed when i bought the car..i think the sensor is located at the second decat if i am not mistaken.. This is why its so low then its ment to be as close to the engine block as posible often before turbo on the manifold, so the egt readings wont mean anything at all, ricky is a very knowledgeable man if he sees your dyno print out im sure he will be shocked. Im actually amazed the dyno operator carried on with the afr that lean most would stop if it went into the 12's Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted February 4, 2015 Share Posted February 4, 2015 the egt gauge is aftermarket and it was already installed when i bought the car..i think the sensor is located at the second decat if i am not mistaken.. In that case pointless, and if reading 800c way too high at the exhaust runners, which would be also reinforce the fact that the AFRs are way too lean. Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted February 4, 2015 Share Posted February 4, 2015 Just had a look at the dyno graph, apart from the AFRs:bang: must have been detting its tits off! I don't like the fact that its scaled by speed rather than RPM, which also begs the question what gear was it making those figures in and was the dyno calibrated correctly...I suspect not, Its very lean IF the AFR figure is correct, but nothing else is so I am doubtful. A compression test and a leak down test would give a good indication of its condition and if there is indeed any damage, next test the fuel pressure and volume, post up a pic of the plug condition? Normal AFRs at 1.2Bar are usually in the 10s Quote Link to comment Share on other sites More sharing options...
Gpro Posted February 4, 2015 Share Posted February 4, 2015 (edited) He is running a stock fuel pump hence his running lean at high rpm (Can't cope) I'm sending him a Walbro 255lph ASAP so hopefully it will fix the issue. But like everyone else said I hope he hasn't damaged anything internally, It doesn't help that his in a very very hot country Edited February 4, 2015 by Gpro (see edit history) Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted February 4, 2015 Share Posted February 4, 2015 The stock fuel pump will flow plenty for BPU and more, unless its faulty, no need to change unless. Quote Link to comment Share on other sites More sharing options...
costas1 Posted February 4, 2015 Author Share Posted February 4, 2015 all pulls were made in 4th gear..the tuner did not here any detonation..most probably we used some octane booster in the fuel..so there is a chance that all numbers here are wrong including afr? Quote Link to comment Share on other sites More sharing options...
Samurai 20V Posted February 4, 2015 Share Posted February 4, 2015 Normal AFRs at 1.2Bar are usually in the 10s Mine actually goes into the 8s at 1.2bar on WOT... Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted February 4, 2015 Share Posted February 4, 2015 Mine actually goes into the 8s at 1.2bar on WOT... Yes the std ECU is a bit OTT once it sees WOT, although 8 is a bit on the excessive side, I would be a little worried about excess wear. Quote Link to comment Share on other sites More sharing options...
Gpro Posted February 4, 2015 Share Posted February 4, 2015 The stock fuel pump will flow plenty for BPU and more, unless its faulty, no need to change unless. All these years everyone says change to a walbro 255lph for bpu was that a mith? Quote Link to comment Share on other sites More sharing options...
Mk4Gaz Posted February 4, 2015 Share Posted February 4, 2015 All these years everyone says change to a walbro 255lph for bpu was that a mith? Not a myth, it's just a safeguard as stock pumps are more than likely circa 20 years old now. I believe, that a new denso 'stock' pump, actually out performs a 255 walbro Quote Link to comment Share on other sites More sharing options...
Samurai 20V Posted February 4, 2015 Share Posted February 4, 2015 Yes the std ECU is a bit OTT once it sees WOT, although 8 is a bit on the excessive side, I would be a little worried about excess wear. I have been meaning to map the car, just never got around to do it.. Got some momentum with the car at the moment, gonna target it by March. Quote Link to comment Share on other sites More sharing options...
Samurai 20V Posted February 4, 2015 Share Posted February 4, 2015 Not a myth, it's just a safeguard as stock pumps are more than likely circa 20 years old now. I believe, that a new denso 'stock' pump, actually out performs a 255 walbro I do believe this is the case, think there is an issue with the Jspec hanger needing mods to accept the Denso.. Walboro is easier to fit... Quote Link to comment Share on other sites More sharing options...
Tricky-Ricky Posted February 4, 2015 Share Posted February 4, 2015 Yes std pump will out perform the Walbro, but as said although the std pump is very good at 20 odd years old its not unusual to replace it for safety, especially if modding for more power. Quote Link to comment Share on other sites More sharing options...
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