marc_w Posted December 8, 2004 Report Share Posted December 8, 2004 I can sympathize with you on the bitterness. If you search for it, you'll find my post from a few months ago that basically said everyone on those other sites don't make any sense / use there knowledge as a 'better than u' stick, and Deezel, Zippy, BigTex, and a few others on here were the only ones who really made sense to me. Yeah, that's definitely how I feel at times. Thank YOU, and thank YOU OTHER GUYS. Link to comment Share on other sites More sharing options...
TurbochargedBerserker Posted December 8, 2004 Report Share Posted December 8, 2004 What's WRT stand for? sorry Bad habit from doing formal proofs... WRT = with respect to About the IFR - The way my truck is set up to see the IFR, is as if it has variable-sized injectors based off of vacuum. At high vacuum, the IFR table is showing the injectors as being larger, because the vacuum is helping 'pull' fuel out of the injector. This tells the computer to hold them open for a shorter period (because they're "larger") to compensate. At low vacuum, they're shown to be lower, because there is not as much vacuum to assist the fuel from being pulled out. This tells the computer to hold them open longer (because they're "smaller") to compensate. It sounds like you don't have a vacuum/boost reference FPR. If you pop your hood and look at the driver's side fuel rail, it's about half way in the middle of the rail and has a vacuum line going to it from the top of the manifold. I know the f-bodies that have the FPR (and non-vacuum referenced) back at the fuel tank all have non-linear IFRs. This leads to a bunch of troubles for FI, but since you're staying NA, it might not be a huge problem for you. I don't really know, though. I've worked with my VE table blindly. I'm currently running one that's been smoothed by about 6 clicks of the "smoothing" button in HPT. ;) I'm not sure whether to do my own SD tuning, or wait for the HPT V1.6 to come out. I've definitely had some tip-in knock, but I'm also getting a lot of false knock now. I'm running the bone-stock HO timing table. I'm seeing 8* of KR at 8* of timing at 4,000rpm with 900 on the 02's. If you want to hear something interesting - I'm scanning 100ft/lbs less power at WOT under these conditions. I'll have to make up my mind about which way to go with SD before looking to desensitize the knock sensors. <{POST_SNAPBACK}> Believe it or not, SD tuning of the VE table is MUCH easier than trying to tune it with the MAF plugged in. Every change you make will have an immediate and understandable effect to LTFTs and performance. Desensitizing the knock sensors is a big no-no in my mind. It's telling to computer not to perform a valid function so that you don't have to fix the trouble maker. I increase my knock decay times and decrease the amount of 'fix' applied to KR, but once I sorted out the tip in, I put them back. Didn't you say you had some noisy rockers? That might be contributing to the KR at 4000rpm. If so, I'd pull the valve covers and check everything out. My KR symptoms went like this: Nothing I did to timing (including running 0 advance) effected KR. Changes to teh VE table (with the MAF plugged in) did nothing either. More fuel? Nada. If you are facing this frustration, take a week off of tuning, come back and do an SD tune. I'll be happy to help every step of the way and will PM you my email / phone if you want more immediate backup than SSS.com. Link to comment Share on other sites More sharing options...
marc_w Posted December 8, 2004 Report Share Posted December 8, 2004 It sounds like you don't have a vacuum/boost reference FPR. If you pop your hood and look at the driver's side fuel rail, it's about half way in the middle of the rail and has a vacuum line going to it from the top of the manifold. I know the f-bodies that have the FPR (and non-vacuum referenced) back at the fuel tank all have non-linear IFRs. This leads to a bunch of troubles for FI, but since you're staying NA, it might not be a huge problem for you. I don't really know, though. No, I don't think I have one... Ignore the red line in the picture (I was trying to highlight a hose that I didn't know anything about)..... http://yo_marc.tripod.com/images/unknown2.jpg Believe it or not, SD tuning of the VE table is MUCH easier than trying to tune it with the MAF plugged in. Every change you make will have an immediate and understandable effect to LTFTs and performance. That's cool... I like immediate results... Desensitizing the knock sensors is a big no-no in my mind. It's telling to computer not to perform a valid function so that you don't have to fix the trouble maker. I increase my knock decay times and decrease the amount of 'fix' applied to KR, but once I sorted out the tip in, I put them back. Didn't you say you had some noisy rockers? That might be contributing to the KR at 4000rpm. If so, I'd pull the valve covers and check everything out. My KR symptoms went like this: Nothing I did to timing (including running 0 advance) effected KR. Changes to teh VE table (with the MAF plugged in) did nothing either. More fuel? Nada. I'm really not sure what do to about the KR. I pulled down the amount that KR attacks, and turned up the recovery rate... I did that to the point where I could actually HEAR the engine knock, but I wasn't comfortable with it at all. It's back to stock now. I did have a bit of a noisy valvetrain (especially with the old cam), but any extra noise is really non existant now. My headers make a bit of noise, but I think it's just the exhaust gasses. They quieted down a huge amount. I can get a video to verify this stuff. I was thinking of turning down the sensitivy a hair at a time until this stuff goes away.... but looking at my logs, I guess a good amount of the hits could very well be from transient problems. If you are facing this frustration, take a week off of tuning, come back and do an SD tune. I'll be happy to help every step of the way and will PM you my email / phone if you want more immediate backup than SSS.com. I'm DEFIINTELY facing this frustration. I'll get familiar with the SD proceedure and setup over the next few days. I'd like to jump into it by the weekend or so. I'll see how far I can get, but you may see a PM or two from me on here. Thanks, I REALLY appreciate the help everyone. Link to comment Share on other sites More sharing options...
TurbochargedBerserker Posted December 8, 2004 Report Share Posted December 8, 2004 No, I don't think I have one... Ignore the red line in the picture (I was trying to highlight a hose that I didn't know anything about)..... http://yo_marc.tripod.com/images/unknown2.jpg Nope, you don't. It would be right around the aluminum pipe that heads over to the passenger side. I'm really not sure what do to about the KR. I pulled down the amount that KR attacks, and turned up the recovery rate... I did that to the point where I could actually HEAR the engine knock, but I wasn't comfortable with it at all. It's back to stock now. I did have a bit of a noisy valvetrain (especially with the old cam), but any extra noise is really non existant now. My headers make a bit of noise, but I think it's just the exhaust gasses. They quieted down a huge amount. I can get a video to verify this stuff. I was thinking of turning down the sensitivy a hair at a time until this stuff goes away.... but looking at my logs, I guess a good amount of the hits could very well be from transient problems. I'd really try to address the tip in first. It may be that you have some valve noise or some noise from the exhaust that should be dealt with, but I think desentizing at this point is just going to mask a potentially more serious problem (real knock) I'll get familiar with the SD proceedure and setup over the next few days. I'd like to jump into it by the weekend or so. I'll see how far I can get, but you may see a PM or two from me on here. Thanks, I REALLY appreciate the help everyone. <{POST_SNAPBACK}> PM sent. Let me know if you have any trouble. Link to comment Share on other sites More sharing options...
zippy Posted December 8, 2004 Report Share Posted December 8, 2004 with the injector location, there is vacuum where the injector is at even under w.o.t. unless you are under boost. with the injector at the intake port, the velocity there gets high enough that it will try to pull fuel out of the injector as the air is rushing past. Link to comment Share on other sites More sharing options...
TurbochargedBerserker Posted December 10, 2004 Report Share Posted December 10, 2004 On the A4 line pressure thing -- here's a quote from Chris@HPT well i've tuned many an A4 MAFless and probably run into line pressure bias on about 3. If you have 9381344 or earlier code there is a higher chance you will have an issue. All it is is that the PCM commands a line pressure bias when the MAF DTC is detected, the capability is in all code, just that GM seemed to stop calibrating things that way after '99. If you run into trans hard shifting with the MAF disconnected email me your bin and i'll fix it up for you. Well be adding the trans DTC options to the editor in future. The other thing to remember is the trans uses calculated torque to determine shift pressures. And calculated torue is based on airflow, so it's important that your airflow numbers (VE table) are in the ballpark. Addresses the torque thing from NoGo's post as well. Link to comment Share on other sites More sharing options...
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