As for open loop all the time, I was speaking to a well knowledge tuner out in New Jersey a while ago and he said they always disable the O2's on these cars which means they would run the bin in open loop all the time.
As for open loop all the time, I was speaking to a well knowledge tuner out in New Jersey a while ago and he said they always disable the O2's on these cars which means they would run the bin in open loop all the time.
Oh I see... I told you what was wrong with your sticky throttle when engine was running, your tuner said to me hahaha... then you did what I said and it worked?Originally Posted by ZEDRATED
So base timing in bin is 6*? Your distributor is set to 10*? So you have added 4* to entire timing table that the ECM knows nothing about? Looking at your timing table in high RPM deceleration the timing is already MAX capable of distributor and you have 4* more so you'll be firing the wrong cylinder... How does that sound like a good plan? You spent $600 on a tune that used the oldest cheapest trick in book to increase power improperly?
Are you recording data to see what is going on? Are you sure your knock sensor is working properly?
No, that means they don't know how to tune the car properly and the only way they can get it to run decent is by disabling CL feedback! I can tune a motor with your specs in Closed Loop! Why can't they?
So they tune a car Open Loop on a 70 degree day and it's spot on right? So only drive the car on 70 degree days and all is well? Hotter and colder days don't matter? Why would you want the car to run good on all days? Why would you want it to be efficiently adjusted all the time? Carburetor didn't so why should EFI?
1990 Chevy Suburban 5.7L Auto ECM 1227747 $42!
1998 Chevy Silverado 5.7L Vortec 0411 Swap to RoadRunner!
-= =-
well i dont want to seem too critical as im still new around here, but i cant belive others here havent pointed this out... first before a tune should be correctly matched parts. sorry, ive been reading this a while now and all i keep seeing is 350 and 30# injectors and my brain jus registers why.
mostly i see whoever put that engine combo together bought parts that seemed impressive rather then to buy parts that matched the engine combo. i mean really 30#injectors and a 1000cfm 58mm throttle body seems way overkill and mismatched, thats like putting a 750 double pump carb on a stock 305 and wondering why it doesnt run right.
no offense and i hope you dont take this observation wrong or to heart but seems most of your tunning issues (battles) are mostly because your base engine/mechanical parts dont match, efi or carbed is all the same when the parts dont match most the effort to get it tuned is wasted on compremises just to get it to run rather then to get it to run great when using correctly matched parts..
tbh i would have probably ditched the accel injectors for a set of 24# bosch III's and 52mm throttle body and i bet half your struggles would go away and your tunes would be way more easily successfull.
just my 2 cents best of luck with it though
also i saw you mentioning why would you want to go with the $6e over what your using , well obviously gm thought there was enough improvment with that file that they bothered upgrading to it.. its pretty much the standard for the 165 f and y maf cars used by tuners. also have you seen how aggressive the spark table is on like the ARAP for $6e as opposed to some of the older files, that alone would be worth it as a great start point although idk without aluminum heads if it would be freindly in stock form. guess it would depend how much compression you have and how much you lose with the cam to know how much advance your engine could take.
Last edited by xtreamvette69; 08-07-2013 at 05:32 PM.
FWIW, I drove my car for about 4 years in OL. Until this summer when I took the car on a 3 hour trip (one way). My tune wass very good in most areas, usually in the mid 14s or leaner while in steady state cruise. I did have it tuned as lean as 16:1 at one point for, in steady state cruise. But that night I had to drive at 60 MPH or below, otherwise my AFRs would go well into the 13s or 12s. Well me being a miser, and not wanting to wash down my cylinders decided it was time to once again try out CL. So I pulled over, pulled fuel out of some of the rich areas, and turned on CL. I have been driving in CL ever since, and it's been great. Well, I did go to open loop for a bit after swapping to much larger injectors that needed more time than I have to tune them in, so I'm back to the original injectors. The only reason I didn't go to CL sooner was because I tried CL early on in my car, and the tune wasn't close enough, so it may drivability poor. I had always intended to turn it on sooner, just never got around to it.
What I find is that many "tuners" believe they are tuning race cars, most race cars don't need CL. Sure they may say to you "This is a street tune", but in the back of their minds they know they are tuning like it's a race car.
The man who says something is impossible, is usually interrupted by the man doing it.
Good points.
I've never understood the 1000 CFM throttle body upgrades for the TPS, when the throttle body has never been the restriction, it's been the runners and base plate that are limiting breathing capability.
This relates to my "I'm building/tuning a race car" mentality. I see so many people who install huge throttle bodies, huge exhaust, big brakes, all of the aftermarket goodies, just to drive near the speed limit on the street with no intention of actually racing the car at a track where the parts might actually be useful. They then wonder why their "Race prepped street car" doesn't perform as well as less modified or even stock versions of the same car.
The man who says something is impossible, is usually interrupted by the man doing it.
Finally some good common sense!
1990 Chevy Suburban 5.7L Auto ECM 1227747 $42!
1998 Chevy Silverado 5.7L Vortec 0411 Swap to RoadRunner!
-= =-
agreed to everything you said six_shooter i see alot of that on vette forums but mostly on the camaro forums (biggest race parts on near stock street cars) i guess people like throwing out those impressive big number parts, my favorit is the ones that put the huge loppy cams in there tuned port engines because they like it sounding tough then find out there came starts where the rest of the motor is done lol
and thanks eaglemark , just glad nobody thought i was too critical but i been itching to post here a while now.
i dont know much about tuning computers yet but i do know a bit about engine combos, basic old school stuff before all this tech. lol
Last edited by xtreamvette69; 08-07-2013 at 05:59 PM.
Heck I thought it was a great post! Keep it up and don't hold back.
We're pretty open here to all views and opinions, although a lot are just plain wrong and we try and get back to facts instead of internet rumors and BS...
1990 Chevy Suburban 5.7L Auto ECM 1227747 $42!
1998 Chevy Silverado 5.7L Vortec 0411 Swap to RoadRunner!
-= =-
@EagleMark, the tuner didn't say hahaha to what you said, you misunderstood me. I was just laughing because my tuner said that the iac wasn't set up right but I had set it right. As for closed loop on this car with the one wire O2 sensor only on the left bank of the engine, I don't think disabling it is a really big deal. What if for some reason the right bank misfires or runs richer than the left for some reason, it'll never be picked up. We used a wideband connected right where the y-pipe meets so I think we got the AFR ready off both bangs when the tune was done. As long as my car runs good that is all that matters. I will drive it around for the next little while and if I am not happy with the way it runs then I'll bring the car back.
Also, I don't think 30lb injectors are overkill for a motor making over 350HP. 24lb injectors would not deliver enough fuel at WOT!
eliminating the o2 sensor is kinda like making your car into a none efi tbh except with more electronic gismos around on it, thats basically how they ran engines before fuel injection .. sure it still has some feedback for self adjustment but the o2 is one of the most important for drivability and economy of a street car.
and belive me you dont have more engine there then 24# injectors could happily handle.. start talking stroker with mods and i will say 30# is where you should be looking.
now dont get me wrong i'm not saying they wont work, i'm just saying there not best suited for your engine not even going to mention how fuel atamization is soo important and when running injuctors that are too large will ruin atamization.
let me explain.. big injectors have a big hole and smaller injectors of course a smaller hole. now when running too big of injectors you will run rich and need to adjust there pulse rate down and or run less pressure or both.
now lets visualize this big hole with little pressure= a wet puddly squirtlike a fire hose or one of them squirt bottles set on stream
littler hole higher pressure= nice mist like the sprayer on a garden hose or one of those squirt bottles set on mist
now wich do you suppose burns faster, cleaner and makes more power?
which do you suppose burns slower, less efficiantly, not as completly and makes less power not to mention passes more unburnt raw fuel to the exhaust?
like i said not trying to pick or be critical here were just all here to learn and i just wanted to point out faults as i see them.
30# will easily handle 450HP+ when you figure they usually will flow 36# @ 58# without even going past 80% duty cycle and those specs are where the 30# would be having nice atamization as well.
many corvettes rolled out of the gm assembly plants sporting 400+ HP and still running under 30# injectors
Last edited by xtreamvette69; 08-07-2013 at 06:44 PM.
Oh! OK...
Yup it's an old system but it worked! Newer systems do have O2 sensors in both banks. Do you think GM and every car company in the world added another O2 sensor because it did not work or because it worked well? The other reason there are now O2 sensors in both banks is newer PCMs can adjust fueling in both banks, yours can not so only one O2 sensor is needed. If you have a problem on the other bank it is a techs job to diagnose it. There is no MisFire detection on your system like there is on newer dual bank fueling dual O2 sensor systems.
I think the real issue is Accell 30LB injectors suck and they won't even give the needed Batt voltage offsets needed for the tune to be properly calibrated. I've done 2 sets now and it's to much work/fudging to get things right and will never do another tune with these injectors.
1990 Chevy Suburban 5.7L Auto ECM 1227747 $42!
1998 Chevy Silverado 5.7L Vortec 0411 Swap to RoadRunner!
-= =-
I forgot to mension that my tuner said that when it was going into closed loop that it was doing funny things and the O2 was either running rich or lean, can't remember which way but I then looked at the wire heading down and sure enough it was burnt because it was touching the header. When I get some time I am going to repair that wire and could I not just set the closed loop temp back down to normal and would it be fine? Can't I just do that. Would the O2 just do some fine tuning to the open loop settings?
If he noticed something wrong with an O2 sensor reading it should have been looked into and fixed. Pretty simple to see a burnt O2 sensor wire if your O2 sensor reading is wrong... ahh never mind just turn it off! That's the icing on cake for me that this guy is worthless and just took your money! There's a big difference in it runs and it runs right!
You could try to enable CL by lowering temp, but how are you going to burn a chip? I doubt you'll have much luck. In the $32 XDF the parameters needed for adjustment for cam and headers are not there. No one has worked on $32 much and even TunerCat does not have them. Reason being is there is no need to. Just swap in a $6E bin file and use the mask/XDF that is ready to use. It was GMs update and enhanced version of a very early system.
These masks are not my strong points and the reason I did not want to do your tune by mail. If the vehicle was left with me I would have, things like throttle blade adjustment or sticky throttle and burnt O2 sensor wires are so easy to fix in person. But at this rate I could have made half what he did and you'd still be way better off...
These situations just really PISS ME OFF! We end up helping people like you that have spent hard earned money and get nothing but poor quality in return. In the last 6 months or so that I decided to do mail order tunes most of my work is fixing other tuners work! The people are very spectacle of paying again and I have done quit a few with "Pay at end if your happy!" So far everyone has paid!
On the other hand you came here for info and we were willing to teach, but that was not your goal. You could have spent half what you did and had all the equipment you needed to do this yourself. I'm really sorry we failed helping you, we also recommended a tuner hands on... sorry.
1990 Chevy Suburban 5.7L Auto ECM 1227747 $42!
1998 Chevy Silverado 5.7L Vortec 0411 Swap to RoadRunner!
-= =-
Well I have a chip burner and 2 chips. I also have a cable so I can datalog.
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