Jake Posted January 9, 2007 Share Posted January 9, 2007 I'm having my car's MoTeC M600 remapped by Dan Turner next week because I'm not 100% happy with how it idles when hot and the off-boost AFRs. (Car spec here) Now, there's a few things I'm wondering about; The fuel pressure is currently set quite high, about 50psi at tickover if I remember right. Should I get this reset to stock pressure before the remapping? I can't see why the 800cc injectors would need raised fuel pressure, or is it because I'm still using the stock fuel rail? The exhaust cam (HKS 264) is currently advanced four degrees. http://img404.imageshack.us/img404/7538/img0191largedn6.th.jpg This seems excessive, I believe the stock cam timing is best, right? So I should reset it before having the mapping done? Spark plugs. Does it matter for the mapping whether I the use NGK coppers (BCPR7ES) that are in there at the moment or should I fit the Denso Iridium IK24s I intend to use in future? Thanks. Quote Link to comment Share on other sites More sharing options...
Homer Posted January 9, 2007 Share Posted January 9, 2007 As you know, I'm no expert but have asked very similar questions in the past few months. Stock cam timing, stock fuel pressure and NGK's should be fine with your setup. Terry S ran (or still runs?) the same setup in the purple monster. Is that Dan the Turbofit mapper? Quote Link to comment Share on other sites More sharing options...
Jake Posted January 9, 2007 Author Share Posted January 9, 2007 Ah thanks. A subtle way of saying SEARCH YOU MOFO!!!ELEVEN! Is that Dan the Turbofit mapper? The very same. Quote Link to comment Share on other sites More sharing options...
Homer Posted January 10, 2007 Share Posted January 10, 2007 Ah thanks. A subtle way of saying SEARCH YOU MOFO!!!ELEVEN! I honestly didn't mean that Jake! Most question were asked outside the forum BTW what gap are the ngk's? 0.8? Quote Link to comment Share on other sites More sharing options...
Jake Posted January 10, 2007 Author Share Posted January 10, 2007 I honestly didn't mean that Jake! I know mate. Wouldn't bother me if you did though. what gap are the ngk's? 0.8? Yeah. They seem fine at that and 1.4bar. Quote Link to comment Share on other sites More sharing options...
Gamer Posted January 10, 2007 Share Posted January 10, 2007 I would leave the cam timing as it is Jake. Dan will be able to adjust them for you if need be. Mine has been tweaked a bit on both the intake and exhaust cams. Quote Link to comment Share on other sites More sharing options...
Jake Posted January 10, 2007 Author Share Posted January 10, 2007 Really? 4 degrees advance sounds like a lot though, doesn't it? I thought maybe he'd prefer to start for a stock position. I suppose it would make more sense if I asked him about it rather than trying to guess. I'm sure he'll make a good job of it. I'll hold you personally responsible if he doesn't Joseph, seeing as you recommended him! Quote Link to comment Share on other sites More sharing options...
Gamer Posted January 10, 2007 Share Posted January 10, 2007 Haha, no problem I am confident that he will do a good job. Just so you know, Both of mine are advanced more than 4 deg. Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted January 10, 2007 Share Posted January 10, 2007 Is that 4 degrees advamced as per the marks on the cam pulley, or 4 degrees real advance, as measured by a degree wheel on the crank and a dial indicator on the cams? It's pointless and almost ceratinly inaccurate to treat the cam pulley marks as gospel. You need to reference them against a reading off the crank, a true TDC measurement from the pistons, and cam lift via a dial gauge. I'd drop the static line pressure to near stock, too, and if you don't have a REALLY good FPR take the opportuinity to swap to one, now. The latest software for the M800 allows dual maps, dunno about the M600, but if it offers this facility you could get another map done on decent fuel, which makes a MASSIVE MASSIVE difference to how much torque and power you can make safely. Quote Link to comment Share on other sites More sharing options...
Ian C Posted January 10, 2007 Share Posted January 10, 2007 It's 2deg on the cam wheel, 4 on the crank, judging by the picture Jake uploaded Advancing the exhaust cam is supposed to have benefits in low and mid range, idle, emissions, and economy -Ian Quote Link to comment Share on other sites More sharing options...
JustGav Posted January 10, 2007 Share Posted January 10, 2007 It's 2deg on the cam wheel, 4 on the crank, judging by the picture Jake uploaded Advancing the exhaust cam is supposed to have benefits in low and mid range, idle, emissions, and economy -Ian Now please tell me I'm talking bollocks, because I am out of my depth here... But I seem to remember on that vid which jamiep put up with that big build, that when degree'ing the cams, that it allows big power, HOWEVER it isn't emmisions friendly, because at some stage both cams are open and effectively the any air the engine is sucking in, goes straight out the exhaust port including any unburnt fuel. I'm only going on what was said, so looking for a correction on my point really. Gav Quote Link to comment Share on other sites More sharing options...
Jake Posted January 10, 2007 Author Share Posted January 10, 2007 Is that 4 degrees advamced as per the marks on the cam pulley ... if you don't have a REALLY good FPR take the opportuinity to swap to one, now. ... you could get another map done on decent fuel, which makes a MASSIVE MASSIVE difference Yes, 4 degrees advance on the crank. I have an Aeromotive FPR which I don't plan on changing. When you say decent fuel makes a massive difference, I presume you're talking about race fuel, right? Quote Link to comment Share on other sites More sharing options...
Ian C Posted January 10, 2007 Share Posted January 10, 2007 Now please tell me I'm talking bollocks, because I am out of my depth here... But I seem to remember on that vid which jamiep put up with that big build, that when degree'ing the cams, that it allows big power, HOWEVER it isn't emmisions friendly, because at some stage both cams are open and effectively the any air the engine is sucking in, goes straight out the exhaust port including any unburnt fuel. I'm only going on what was said, so looking for a correction on my point really. Gav That's overlap and is great for tuning NA's for maximum power. The exhaust valves are still closing on the end of the exhaust cycle and the intake valves are opening early for the intake cycle and the velocity of the exhaust gas expanding down the exhaust manifold runners causes a vacuum in the cylinder which drags the intake charge in. Works great at high revs full throttle, as it can push an NA's engine up to and even a bit beyond 100% VE. Under any other circumstances though it has a negative effect. If the engine is turning slowly then what you said happens - the intake charge of air and fuel has enough time to partially whistle straight back out of the exhaust valve, thus buggering up your cylinder filling. On a turbo car a lot of overlap is bad because the turbo puts a load of back pressure in the way, and removes the exhaust tuning pulse effect. This causes the opposite effect from an NA engine as the exhaust gas expands in the other direction - towards the intake valves. It's the path of least resistance. So you get reversion, and the intake charge is contaminated with exhaust gas, losing you power but not necessarily causing environmental concerns I'm far from sure what's good for turbo cars but I know overlap isn't all that great. Apparently the most important bit is when the intake cam closes, that's the one which makes all the difference and that explains why some VVTi systems are intake only. It's fascinating stuff but reading only gets you so far. I'm working with someone to figure out an easy way of finding if changes are 'better' or 'worse' and at what points they are better or worse across the rev range (as I very much doubt it's linear), all from a quick blat-and-datalog. Then I can mess with my adjustable cam gears when the weather improves -Ian Quote Link to comment Share on other sites More sharing options...
JustGav Posted January 10, 2007 Share Posted January 10, 2007 Hmmm, very interesting... This is something I will have to start reading into as well. Cheers for the detailed answer btw, filled in some holes in my understanding. Will post up any info I find. Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted January 10, 2007 Share Posted January 10, 2007 What I am asking is has anyone degreed in the cams, or have they just assumed the crank TDC mark, and the cam O degree marks are accurate, `cos they probably are not. The 4 degrees on the cam pulley(s) may well not be a real 4 degrees from where they should be. Quote Link to comment Share on other sites More sharing options...
JustGav Posted January 10, 2007 Share Posted January 10, 2007 Again, this comes from the video... They appeared to pretty much ignore the TDC markings on the crank , and double checked that no 1 was at TDC, and then rolled the crank over till they had 0.05" (I think) lift on the cam (Again, why is this figure used, it can't be fully open at 0.05 can it?). Here is a link http://www.hotrodder.com/kwkride/degree.html Edit : Correction to the above.. It appears that you roll the cam over completely and reset the gauge on the valve to zero when it is at maximum lift and then degree the cam to suit 0.05" from fully open. Quote Link to comment Share on other sites More sharing options...
Ian C Posted January 10, 2007 Share Posted January 10, 2007 5 thou is an industry standard accepted level of lift to class as "starting to open", as far as I know. Chris, would you say that once you degree the cam gear in the first time, and get it to a known state, you could then make subsequent adjustments by simply changing the position of the gear according to it's degree marks. For example, you degree it in and have to set them to -1.5deg. If you wanted then to try 2deg retard, you could simply move the gear to -3.5deg without taking the top part of the engine apart and setting up the measuring gear again? (Er bit of a hijack this, sorry Jake, let me know if you want this thread split up) -Ian Quote Link to comment Share on other sites More sharing options...
JustGav Posted January 10, 2007 Share Posted January 10, 2007 5 thou is an industry standard accepted level of lift to class as "starting to open", as far as I know. Chris, would you say that once you degree the cam gear in the first time, and get it to a known state, you could then make subsequent adjustments by simply changing the position of the gear according to it's degree marks. For example, you degree it in and have to set them to -1.5deg. If you wanted then to try 2deg retard, you could simply move the gear to -3.5deg without taking the top part of the engine apart and setting up the measuring gear again? (Er bit of a hijack this, sorry Jake, let me know if you want this thread split up) -Ian Assumption here as well... Ian, seems to make sense for quick checks. Although I suppose for absolute certainty you would want to degree the new setting again to be sure. Since it is unlikely for the crank to have moved out of alignment I wouldn't have thought it would be needed and you could adjust using the cam pulleys. (Just need to make sure you don't forget what your original settings where)... Might be an idea to split this to a new thread perhaps (apologies Jake) Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted January 10, 2007 Share Posted January 10, 2007 5 thou is an industry standard accepted level of lift to class as "starting to open", as far as I know. Chris, would you say that once you degree the cam gear in the first time, and get it to a known state, you could then make subsequent adjustments by simply changing the position of the gear according to it's degree marks. For example, you degree it in and have to set them to -1.5deg. If you wanted then to try 2deg retard, you could simply move the gear to -3.5deg without taking the top part of the engine apart and setting up the measuring gear again? (Er bit of a hijack this, sorry Jake, let me know if you want this thread split up) -Ian If you are happy to assume the marks are accurate, yes. I'd double check the marks if you are not 100% happy about them, using the degree wheel on the crank. This is something that's a LOT easier with the engine out of the car, and one of the reasons I love engine dynos, as you can easily bugger about with stuff like this. Quote Link to comment Share on other sites More sharing options...
Ian C Posted January 10, 2007 Share Posted January 10, 2007 If you are happy to assume the marks are accurate, yes. I'd double check the marks if you are not 100% happy about them, using the degree wheel on the crank. This is something that's a LOT easier with the engine out of the car, and one of the reasons I love engine dynos, as you can easily bugger about with stuff like this. Yes, that's true, but santa didn't bring one of them so it's test track alpha one one for me If doing a battery of tests 2deg apart I think the cam degree markings would suffice. -Ian Quote Link to comment Share on other sites More sharing options...
b_have Posted January 10, 2007 Share Posted January 10, 2007 5 thou is an industry standard accepted level of lift to class as "starting to open", as far as I know. Chris, would you say that once you degree the cam gear in the first time, and get it to a known state, you could then make subsequent adjustments by simply changing the position of the gear according to it's degree marks. For example, you degree it in and have to set them to -1.5deg. If you wanted then to try 2deg retard, you could simply move the gear to -3.5deg without taking the top part of the engine apart and setting up the measuring gear again? (Er bit of a hijack this, sorry Jake, let me know if you want this thread split up) -Ian Its 1.25mm (0.050") Quote Link to comment Share on other sites More sharing options...
Ian C Posted January 10, 2007 Share Posted January 10, 2007 Its 1.25mm (0.050") Oops I saw fifty thou and wrote five. My bad. -Ian Quote Link to comment Share on other sites More sharing options...
JamieP Posted January 10, 2007 Share Posted January 10, 2007 Hi jake, did tunning jap give up the password then? what day are you over there? he is doing mine next week aswell. Quote Link to comment Share on other sites More sharing options...
Jake Posted January 10, 2007 Author Share Posted January 10, 2007 Hi Jamie, Tut tut, Hi-jacking Gav's cam overlap (or whatever they're going on about now) thread. Next Wed's he's doing it. "Wellington place, Bletchley" is that TurboFit's place then? I didn't know they had a Dyno there. Quote Link to comment Share on other sites More sharing options...
JamieP Posted January 10, 2007 Share Posted January 10, 2007 Hi Jamie, Tut tut, Hi-jacking Gav's cam overlap (or whatever they're going on about now) thread. Next Wed's he's doing it. "Wellington place, Bletchley" is that TurboFit's place then? I didn't know they had a Dyno there. No thats the place they use for dynoing till they get there own. Quote Link to comment Share on other sites More sharing options...
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