gaz1 Posted April 22, 2007 Share Posted April 22, 2007 If you take the time to read the 1st thread you will realise that i don't give a shit about the bhp. My point is this. Buy a car with Nur Spec exhaust induction system and according to Dyno running 350 bhp at 1 bar boost. I did a 13.25 quartermile. I then decatted the car, FMIC, hybrids, 550 injectors, running 1.3 boost etc etc. This should in principal give me a better result and it is not. I only want to know if there might be something in that combination that I am overlooking. Not interesred in another boring dyno argument. as homer just said there is a lot of other factors that don,t mean you will better your time on that occasion, because you have more power but you may well a different day ie better grip, cooler air Quote Link to comment Share on other sites More sharing options...
leonv Posted April 22, 2007 Author Share Posted April 22, 2007 Ric was making a very valid point - that RR figures cannot be relied upon. The inital power figure is way off what a stock car would be, which means the 2nd shouldn't be relied upon (bad RR/operator). What it does show is the car has made an apparent 60bhp increase with the decat & hybrids (assuming the results are form the same RR). However that won't necessarily mean a better time. One thing the results from yesterday showed is drag times are much more down to driver, weather, track condition (it changes dramtically between days, and even time of day, humidity, sunlight, what has run before you, etc), blah, blah. Now, that answer is all I am looking for. Positive feedback on my question. Cheers Homer Quote Link to comment Share on other sites More sharing options...
JamieP Posted April 22, 2007 Share Posted April 22, 2007 Hey leon, id start with checking for boost leaks then take the car back to the same dyno to see what effect the mods have made and take it from there:) Quote Link to comment Share on other sites More sharing options...
leonv Posted April 22, 2007 Author Share Posted April 22, 2007 How have you remapped it to take account of the new boost curves? I am not a fan of hybrids, even on an engine with a proper ecu. They just don't work well as the EXHAUST side is too small, and it's not possible to make it a worthwhile amount larger, so with a bigger or cut back compressor the things become imbalanced. The car has never been remapped Chris. Was under the impression and advised that with this mods the standard mapping is still sufficient. Quote Link to comment Share on other sites More sharing options...
leonv Posted April 22, 2007 Author Share Posted April 22, 2007 Hey leon, id start with checking for boost leaks then take the car back to the same dyno to see what effect the mods have made and take it from there:) Cheers Jamie Will check for boost leaks as a first step and get it on a dyno. Quote Link to comment Share on other sites More sharing options...
R Black Posted April 22, 2007 Share Posted April 22, 2007 What was the temperature like this time last year? Quote Link to comment Share on other sites More sharing options...
Bobbeh Posted April 22, 2007 Share Posted April 22, 2007 Can I just make a suggestion here? Wasn't it Santa Pod that had a resurface recently? I seem to remember reading about how cars were generally getting slower than expected times. Just a thought. Nothing to do with that, lots of people have raced there before and tbh it didnt feel any different to me. 350 bhp isnt stock.. so the term shouldnt be used. I remember someone saying Ryan Woon got a 13.0 in a stock Supra.. I just cant believe that no matter how good of a driver on the 1/4 he is. Quote Link to comment Share on other sites More sharing options...
Whitesupraboy2 Posted April 22, 2007 Share Posted April 22, 2007 whats the theroitical best quarter you could get in a stock supra? or what is the best seen with timing slip proof? Quote Link to comment Share on other sites More sharing options...
jaymdee Posted April 22, 2007 Share Posted April 22, 2007 FWIW, I ran 13.25 with 110.3 mph terminal @1Bar yesterday. I also ran a range from 13.7-14.2 @0.8 Bar (which is how I run the car on the road) I do have a single decat, exhaust & FMIC, which I think may have helped at the higher boost pressure, but at stock boost I was getting times consistant with other stock cars. Quote Link to comment Share on other sites More sharing options...
Bobbeh Posted April 22, 2007 Share Posted April 22, 2007 Both Scooter and myself have run 13.8s in our UK manuals, with both cats in and standard boost. His was running in TTC mode according to him when I asked about his time. Mine was in sequential. I dont know what he did with his tyres - like pressures etc tho. Quote Link to comment Share on other sites More sharing options...
leonv Posted April 22, 2007 Author Share Posted April 22, 2007 Nothing to do with that, lots of people have raced there before and tbh it didnt feel any different to me. 350 bhp isnt stock.. so the term shouldnt be used. I remember someone saying Ryan Woon got a 13.0 in a stock Supra.. I just cant believe that no matter how good of a driver on the 1/4 he is. Give it a rest. All I was saying is that it was not full BPU, not hybrids, not single. Please send me how to use the forum handbook. I apologise deeply for saying stock and for the RR giving me the wrong bhp. Quote Link to comment Share on other sites More sharing options...
Bobbeh Posted April 22, 2007 Share Posted April 22, 2007 Hey, its only confusing for the rest of us when we're trying to benchmark cars etc No worries 13.25 is still a nice time, stock or not! Check out jaymdees time, very similar to yours at 1 bar! Quote Link to comment Share on other sites More sharing options...
Gazboy Posted April 22, 2007 Share Posted April 22, 2007 The car has never been remapped Chris. Was under the impression and advised that with this mods the standard mapping is still sufficient. I may have this wrong, but I was always under the impression that the stock ecu only has fuel maps for upto 1 bar- over 1 bar and the ecu switches the injectors to maximum duty cycle, with your 550's even more juice is being squirted in than if you had left the 440's in??? Have I got this wrong chaps? Quote Link to comment Share on other sites More sharing options...
Homer Posted April 22, 2007 Share Posted April 22, 2007 I may have this wrong, but I was always under the impression that the stock ecu only has fuel maps for upto 1 bar- over 1 bar and the ecu switches the injectors to maximum duty cycle, with your 550's even more juice is being squirted in than if you had left the 440's in??? Have I got this wrong chaps? Good point Gaz, I completely missed that in the first post! Leonv, was your car originally a Jspec? You mentioned you had 550's installed, what was done to remap the ECU to cope with the larger injectors? If no ECU changes have been done your car will, if anything, be down on power due to overfuel. That would explain the slower times for sure. Quote Link to comment Share on other sites More sharing options...
leonv Posted April 22, 2007 Author Share Posted April 22, 2007 Good point Gaz, I completely missed that in the first post! Leonv, was your car originally a Jspec? You mentioned you had 550's installed, what was done to remap the ECU to cope with the larger injectors? If no ECU changes have been done your car will, if anything, be down on power due to overfuel. That would explain the slower times for sure. It is a Jspec. Was advised that I would not need remapping putting in 550's and the resistor pack. Quote Link to comment Share on other sites More sharing options...
Homer Posted April 22, 2007 Share Posted April 22, 2007 It is a Jspec. Was advised that I would not need remapping putting in 550's and the resistor pack. Ah, no you cannot do that mate The ECU is designed to fuel for the 440cc injectors, fitting 550's means it is overfueling across the entire rev and boost range by 25%. Though this means an increase in power at the peak rev range (as you decatted at the same time), it will be massively overfueling everywhere else. You must have an aftermarket ECU (or piggyback) and it fully mapped to run 550 injectors on a jspec. A cheap alternative is to purchase something like an SAFC2 to fudge the AR map. It also explains the weird RR results, they are just wrong. I wasn't going to mention it earlier but only a 60 bhp increase is far to little, most see at least 100bhp increase at peak with a full decat (never mind hybrids). It must run like a dog now, especially at lower boost levels. Sorry to be the bearer of bad news. On the plus side, it can be fixed and you have a potential for a massive power increase over how it runs now Quote Link to comment Share on other sites More sharing options...
Kranz Posted April 22, 2007 Share Posted April 22, 2007 It is a Jspec. Was advised that I would not need remapping putting in 550's and the resistor pack. And our survey says........ XXXXXXX Someone gave you wrong advice there dude. Especially if you're running over 1 bar. 440's would have overfuelled big time, but 550's will be pouring it in by the bucket full! If you have no fuel controller at all you'll be so rich it'll not burn properly, resulting in MUCH less power than its good for. Edit - Gruggs has a SAFC2 fuel controller I was going to buy. Was £100. Something like this will get you the 100hp you're missing Quote Link to comment Share on other sites More sharing options...
Gazboy Posted April 22, 2007 Share Posted April 22, 2007 Ah, no you cannot do that mate The ECU is designed to fuel for the 440cc injectors, fitting 550's means it is overfueling accross the entrie rev and boost range by 25%. Though this means an increase in power at the peak rev range (as you decatted at the same time), it will be massively overfueling everywhere else. Under 1.0bar boost shouldn't he have the correct fueling as the car still has those maps? Quote Link to comment Share on other sites More sharing options...
Kranz Posted April 22, 2007 Share Posted April 22, 2007 It also explains the weird RR results, they are just wrong. I wasn't going to mention it earlier but only a 60 bhp increase is far to little It hsan't been on an RR since the 550's were fitted and all the other mods, so it may have even gone backwards from 350 bhp Quote Link to comment Share on other sites More sharing options...
Homer Posted April 22, 2007 Share Posted April 22, 2007 Under 1.0bar boost shouldn't he have the correct fueling as the car still has those maps? Nope, the ecu is expecting to have 440cc injectors so will supply X amount of duration and duty to them. As the injectors are 25% larger, they will supply 25% more fuel. (Techie guys, thats a simplistic expaination, I know ) Quote Link to comment Share on other sites More sharing options...
Homer Posted April 22, 2007 Share Posted April 22, 2007 It hsan't been on an RR since the 550's were fitted and all the other mods, so it may have even gone backwards from 350 bhp The rest of the rev range would be terrible, but it will have more at peak power (high boost, high rpm) as it was decatted and hybrided (is that a word?) at the same time Quote Link to comment Share on other sites More sharing options...
Kranz Posted April 22, 2007 Share Posted April 22, 2007 Under 1.0bar boost shouldn't he have the correct fueling as the car still has those maps? No, it will only (possibly) have the right fuelling within closed loop operation whan the O2 sensor can control the fuellings. Outside of there it will have Jspec richness (11 AFR??) plus 25% more fuel (maybe 9 AFR???). Quote Link to comment Share on other sites More sharing options...
leonv Posted April 22, 2007 Author Share Posted April 22, 2007 Ah, no you cannot do that mate The ECU is designed to fuel for the 440cc injectors, fitting 550's means it is overfueling across the entire rev and boost range by 25%. Though this means an increase in power at the peak rev range (as you decatted at the same time), it will be massively overfueling everywhere else. You must have an aftermarket ECU (or piggyback) and it fully mapped to run 550 injectors on a jspec. A cheap alternative is to purchase something like an SAFC2 to fudge the AR map. It also explains the weird RR results, they are just wrong. I wasn't going to mention it earlier but only a 60 bhp increase is far to little, most see at least 100bhp increase at peak with a full decat (never mind hybrids). It must run like a dog now, especially at lower boost levels. Sorry to be the bearer of bad news. On the plus side, it can be fixed and you have a potential for a massive power increase over how it runs now Cheers Homer. I will look into this. I've heard negative feedback before on the forum about hybrids. I just didn't want to throw even more money at a lost cause. Quote Link to comment Share on other sites More sharing options...
Homer Posted April 22, 2007 Share Posted April 22, 2007 Cheers Homer. I will look into this. I've heard negative feedback before on the forum about hybrids. I just didn't want to throw even more money at a lost cause. This has nothing to do with hybrids mate, ignore those for now. You have a serious fueling problem. TBH, I wouldn't even drive the car as it is with the 550's in. Quote Link to comment Share on other sites More sharing options...
Kranz Posted April 22, 2007 Share Posted April 22, 2007 The rest of the rev range would be terrible, but it will have more at peak power (high boost, high rpm) as it was decatted and hybrided (is that a word?) at the same time Hybridised? Hybridated? Hybrated? I think he needs to get a wideband and a SAFC2 as a minimum Quote Link to comment Share on other sites More sharing options...
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