To start off with, for those who are gonna attack their keyboards with lightning quick fingers and post witty responses like, "That time sucks", I know, that's what this post is about (why do I feel like someone is still going to post that... lol)

Alright, so here's how the craptastic embarrassmentathon went:

RUN 1 Not a great reaction time, but not horrible, with a little bit of spin for a 60 of 2.3. First and second gears "allowed" me to get it up around redline before shifting, but it was in third and beyond that I started to feel a moderate amount of bog coming on. It was enough that I couldn't punch through them (the gears), and basically just had to step into the gas smoothly, shifting just before 4000. That essentially destroyed any chance of making a valid pass, and ended up tossing me a 15.7 (I still cringe when I type that).

RUN 2 I was pretty pissed about the first run, so I decided to turn the methanol injection on (set to spray from about 7 PSI onward) and lay into every gear with a redeeming vengance. Uh, yeah, huge mistake. A similar 60 time, but with a faster reaction time, which was then followed by a bogorama. Just when I hit 4000 in first, whoomph, it tosses me forward in my seat it bogs so hard. By the time I actually made it into fourth, I was happy just to be in gear and rolling at a consistent speed, so I more or less drove the car to the line from that point out. I think that run was somewhere near the speed of sound, as my time was 17.5.

RUN 3 Screw it. I kill the methanol and lean out the fuel a bit via my BEGi FPR. I'm not even really sure how to explain this run, though one person who had come over to talk to me after put it best, "What the hell happened on that run? It sounded like you were running under water." It kinda went, launch, hit 4000, BOG, shift, hit 4000, BOG, shift, hit 4000, BACKFIRE, shift, then at this point I was in fourth, and actually just started braking before the line so that I could conveniently use the first turnout lane. I'm damn near positive I breached the sound barrier on that one 'cause I laid down a pavement pounding 18 point something-or-other.

That was it for me. In a huge field where I was the only "sport compact" I had a lot of eyes on me, and instead of representing the J-body, I embarrassed the hell out of myself. I guess on a positive note, each run was so bad, and progressively worse, that everyone knew that my car was running like a gigantic pile of steaming turds. Hell, even my mother, who was sitting in the stands, came into the pits after my second run and asked me what the hell was wrong with my car.

So, as for the issue, it would appear as though at 4000 RPMs something happens:

-Yes, I tuned the fuel before I got to the track, with AFRs of around 12-13 in boost (though dipping to 11s in bad spots at higher boost)
-No, I don't know what the AFRs were when was I was running, as being the genius that I am, I forgot to log the data on my Innovate
-The plugs were installed before I left town, and it's only about an hour and a half drive to where the track is
-I actually tripped a CEL for the first time (system too rich), but this also happened the day before when I first ran my methanol injection (50/50 mix)
-I kept my OBD plugged in afterwards to continually clear the code, and it became worse and worse to the point where it only took about 1 second for the code to reappear after it had cleared

This is where I ask for ideas. Some things you might want to know:

-The fuel is tuned with a rising-rate BEGi FMU
-There is no "electronic" tune (no reflash, no HPTuners, no MegaSquirt, but I do have an MS box sitting in my garage that I'll be installing soon...)
-Stock MAP sensor
-Spark is controlled by an MSD DIS-2 (the "old-school" jumper-style)
-The plugs are Bosch HR7DC coppers, gapped to 0.035
-There are no issues up to 4000 RPMs, and it runs like a rocket ship to that point
-Sometimes, it will push past the 4000 mark and continue to pull hard and churn out boost all the way into redline
-Wanting to see what happens if I stay in the gas when it starts to bog, it obviously slows down, then shoots a cannon of a backfire, and then starts to pull nicely again
-No, I haven't checked the plugs since I got back (just wanted to take it easy tonight and leave the car alone for once)
-The wideband has been giving me asinine readings lately when in high boost, sometimes dropping to 10s and then instantly spewing out readings of 28:1 and higher, or barfing out percentages instead of actual ratios

Some ideas floating around are:

-Issues with the FMU
-Plug gap may need to be altered
-Loose connection at the MAP or TPS
-Issues with the MSD

If you read this far, thanks, and the same goes for anyone offering helpful suggestions.

wow..... sounds like its running about as well as our drag car has the last few times out. I just got home from work (last week on 2nd shift, WOOT), so I wont be much help right now...... I'll try to remember to post back in the morning. I do my best thinking while I'm sleeping




SPD RCR Z - '02 Z24 420whp
SLO GOAT - '04 GTO 305whp
W41 BOI - '78 Buick Opel Isuzu W41 Swap

Quote:

-The fuel is tuned with a rising-rate BEGi FMU
-There is no "electronic" tune (no reflash, no HPTuners, no MegaSquirt, but I do have an MS box sitting in my garage that I'll be installing soon...)
-Stock MAP sensor

There is your problem.

you are running 17psi of boost without any real tune? Get rid of the FMU and start the megasquirt install. Even without the Megasquirt controlling the spark.... just fuel, your going to see a massive improvement.

In addition your RC 320cc injectors are NEVER going to keep up with 17psi of boost. We are talking 550cc here. Your 320s would have to run at like 200% duty cycle (im exagerating they wont even function) to keep up!

To sumerise:

a) propper tunning, take out the FMU and thow it in the ditch if your running more than 5 psi of boost.
b) you need way bigger fuel injectors.... like waaaaaaaaay bigger (and for oversize injectors you needd accurate fuel control...... see "a")




"Go Before Show Yo."
CARCUSTOMS.NET, THE BEST SERVICE ON THE ORG!!!

Gameoverracing. wrote:

Quote:

-The fuel is tuned with a rising-rate BEGi FMU
-There is no "electronic" tune (no reflash, no HPTuners, no MegaSquirt, but I do have an MS box sitting in my garage that I'll be installing soon...)
-Stock MAP sensor

There is your problem.

you are running 17psi of boost without any real tune? Get rid of the FMU and start the megasquirt install. Even without the Megasquirt controlling the spark.... just fuel, your going to see a massive improvement.

In addition your RC 320cc injectors are NEVER going to keep up with 17psi of boost. We are talking 550cc here. Your 320s would have to run at like 200% duty cycle (im exagerating they wont even function) to keep up!

To sumerise:

a) propper tunning, take out the FMU and thow it in the ditch if your running more than 5 psi of boost.
b) you need way bigger fuel injectors.... like waaaaaaaaay bigger (and for oversize injectors you needd accurate fuel control...... see "a")

I concur.

Also, check into the MSD if installing megasquirt doesn't solve the problem. Backfires and loud pops are usually the ignition system retarding timing too much. Thats how I get the skwirl to shoot large flames out the exhaust. If the MSD has a reference for boost, it may be pulling WAY too much timing in relation to MAP sensor input.

in fact, you may want to start there first.

defiantly ditch the fmu and get some real type of tunning software aboard, you spent all that money on the motor shouldnt of bandaided it with a fmu and try and run 17psi, i would say with your setup you might be able to run 5-7psi safely, those 320s will never be enough to support 17psi, brian maxed out his 650s on 15psi...... so if i was you i would turn the boost down to 5-7psi for now to make the car driveable, buy new bigger injectors 750cc, and start installing your mega squirt




R.I.P. Brian Klocke, you will never be forgotten

It seems as though the general consensus is an incorrect injector/FMU to boost pairing. There are a number of issues I have with just accepting this theory and moving forward:

-I can get the exact same results running 5, 6, 7, 8, 9, 10, etc PSI.
-The fuel is there when I'm running higher boost. If anything, there appears to be too much, as it's always in the higher boost ranges that I'll see "trouble spots" of 9:1 and 10:1 AFRs.
-It pretty much always happens at around 4000 RPMs, regardless of what gear I'm in, or how much boost is being produced.
-Backfires are characteristic of unburnt fuel, not lack off.
-It is throwing "system too rich" codes, not system lean CELs.
-It's not misfiring and choking itself out, it's bogging and drowning itself, and with the exception of being able to feel a few "pre-shudders" sometimes, it happens all at once, not like when a car begins to cough out misfires.
-If I keep the same fuel curve and introduce the methanol, it runs worse. If the system was leaning out, or the injectors were failing, or the FMU wasn't allowing for proper fuel delivery, the methanol would help to compensate, not hamper it. I'm not in any way, shape or form saying that it would be a magical cure, but, to at least some minor extent, I would see a minute and tiny improvement, and not a total and complete worsening scenario.

Just as PJ had touched on, I'm leaning more in the direction of too much timing pull via the MSD. If I'm still not being grumpy about the whole thing, I'll check that out tonight.

I'm also going to try to get video. I'll try to have the tach, boost and wideband controller in the same shot so everyone can better see what I'm talking about, as well as have a visual reference for the AFRs in comparison to everything else that's happening .

As for the FMU being a "band-aid", I just want to touch on that and state that I comprehend that it's far from the ideal setup, but after dropping $2000 that I don't have (and am still paying back) on a transmission and plane tickets, my car won't being seeing another dime for quite some time. I do however, have the MS in my garage along with some 550 RCs, so once I finish a few things on my GF's car and get my Jimmy up to par so that I can sell it, I'll focus my efforts on the MegaSquirt install.

Thanks.

DaFlyinSkwirl (PJ) - BPU++ wrote:

Gameoverracing. wrote:

Quote:

-The fuel is tuned with a rising-rate BEGi FMU
-There is no "electronic" tune (no reflash, no HPTuners, no MegaSquirt, but I do have an MS box sitting in my garage that I'll be installing soon...)
-Stock MAP sensor

There is your problem.

you are running 17psi of boost without any real tune? Get rid of the FMU and start the megasquirt install. Even without the Megasquirt controlling the spark.... just fuel, your going to see a massive improvement.

In addition your RC 320cc injectors are NEVER going to keep up with 17psi of boost. We are talking 550cc here. Your 320s would have to run at like 200% duty cycle (im exagerating they wont even function) to keep up!

To sumerise:

a) propper tunning, take out the FMU and thow it in the ditch if your running more than 5 psi of boost.
b) you need way bigger fuel injectors.... like waaaaaaaaay bigger (and for oversize injectors you needd accurate fuel control...... see "a")

I concur.

Also, check into the MSD if installing megasquirt doesn't solve the problem. Backfires and loud pops are usually the ignition system retarding timing too much. Thats how I get the skwirl to shoot large flames out the exhaust. If the MSD has a reference for boost, it may be pulling WAY too much timing in relation to MAP sensor input.

in fact, you may want to start there first.

No offense but 320cc's even with an fmu are laughable at least. I was running 650's and seeing 60% injector duty cycle at 18 psi... those injectors are like... heeelllpppp meeee....

lol yeah get your fuel straightened out and check the msd out



LE61T PTE6262 Powered

if you want to check the MSD first, thats fine. Its a little easier to check that out since all it is is some settings

but bear in mind, FMUs are difficult to tune since they're purely mechanical and don't compensate for slight changes in situation (weather, altitude, etc) nobody's saying this is making you run too lean.. it could be making you run way too rich.

also, anything over 100% duty cycle means you have an injector firing into a closed intake valve, which means once the exhaust stroke happens all that extra fuel is going to pre-load the cylinder and unburnt fuel will make its way out the exhaust and onto your O2 sensor (giving you rich codes) as well as fouling plugs and just making the car run like crap.

upgraded injectors would not hurt at all and wouldn't cost that much (ebay 650s or bigger go for what? $250 a set or so?)duty cycle HAS to stay below 80% so the injector can accurately control its pulsewidth and get the proper AFR you're looking for. anything more than 80% the injector is going to be rushing to get the fuel in that it gets backed up and is forced to "rush"

ever see the "I love Lucy" episode where she's on the assembly line making pies and it keeps going faster and faster? same principal with your injector. If there were more people on the line (bigger injector) the extra work load can be compensated for. your basically getting fuel everywhere because the injector is just blindly firing as fast as it can.

and FMUs just aren't flexible enough for a higher boost EFI car. a computer controlled injection system is a much, much better option

even tho you see the same afr no matter what psi doesnt mean your injectors are working in the proper way, im saying your injectors are probably only good for 5-7psi before you duty cycle is too high



R.I.P. Brian Klocke, you will never be forgotten

Well, I can check this out too. I have a set of RC 550s in the garage that I've kept out of the car as cold starts already turn into an exhaust smoke show with the 320s, and I didn't want to be blindly (due to lack of "electronic" tune) dumping anymore fuel in there with the whole closed loop issues.

Before I go wasting my time, is it even going to run half-assed with the 550s in there sans HPTuners (or the MegaSquirt)?

If so, yeah, I'll take the time to dump those in there as time-wise, that's nothing compared to getting the MS operating properly (Eventually, as mentioned, yes, I'll get the MS box running. But for now, I've spent way too much time dicking around with the car, and not enough time on other crap that needs to be done. It is a slap in the face though every time I'm in the garage and see the MegaSquirt lying there, "Install me dumbass, install me now", lol).

Thanks again.

i agree with running the 550s... a buddy of mine has an Integra LS b18b1 on RC330 injectors... and his boost controler went bad, so instead of maxing out at 10 lbs, it kept going... at about 15 lbs (around 5000 RPMs ) his car started to bog, and you can hear the blow off valve starting to blow off before he let off the pedal...so we ran it straight to the waste gate which defaults at 8 and the problem has gone away... hes waiting on getting his HonData installed to put in the 550 injectors....

i would agree too that you would want to be tuned before running the 550s

its not your msd,spark plugs,injectors,fmu or your tune. your leaning out or i should say running out of gas let me guess when u get on a dyno u have no problems getting good a.f ratios and pulls strong when u drive the car normal its fine but when u go to the track (with very little gas in the tank to save weight )it takes off good in first but than u run out of power at the end of each gear and it starts bogging and back firing. all these problems sound like some one has a blazer pump in there tank. when u take off all the gas goes to the back of the tank and the pump sucks the cup dry and u run out of power than the car slows down the gas runs back to the front than the pump gets its gas again it makes power again the car takes off and the gas runs to the back of the tank and on and on we go that why your getting the crazy a f readings. the easy way to make sure this is the problem is fill your tank as full as u can get it before u go to the track if its the problem ether swap in a new stock pump or put a low pressure pump under the car that sucks the gas from the bottom back corner of the tank and puts the gas back into the cup around the in-tank pump so its always primed. u will need a 2000 up pump cup that has not been cut up for this to work i did this to my car and it works perfect .

hot damn even i pull a 15.2 all day--14.976 best

injector clipping?

when you say it it tosses me forward in my seat it bogs so hard....

does it feel like the car suddling stopped making power like a wall stopped it? or kinda slowly started to loose power and fell on its face then bogged.

from what you describbied, it sounds like it was running lean and starving from fuel.. 13s a/f isnt really safe at 17psi.. or any boost....


if u were running to rich it would bog down and kinda die out power wise but still semi pull.

sounds like injectors clipping possibly.

with that kind of boost, an fmu alone cannot supply a safe amount of fuel accross the rpms. it just increases fuel pressure.

11s a/f is perfect.. and the fact it still did it with meth injection (assuming 100% that the meth injection worked that pass) then it pretty much narrows it down to your fuel system.



12.5@116 2.0 60ft

what was the mph



1989 Turbo Trans Am #82, 2007 Cobalt SS G85

i just looked at your mod list. u have a nice setup, why on earth would u even chance running at that kind of boost level with only a fmu!?

a built motor will last longer in dangerous conditions like that, but its not unbreakable.. id highly recomond not boosting until u get a real fuel sytem in there.... your gonna kick yourself in the ass hard if you toast a fully built motor because you didnt wanna wait to do it right or spend a few extra hundred bucks.



12.5@116 2.0 60ft

Alright, where to begin:

First off, I'm getting bigger injectors. Yes, bigger than the 320s that are currently installed and bigger than the 550s I have sitting in my garage. Most likely I will be throwing in 1000s, as though 750s might do, the motor, when built, was built to run 20 PSI and withstand spikes to 25. According to the RC site, using their calculator (being that they actually manufacture injectors for a living, I'm going to throw quite a bit of trust in their corner) 750s, seeing a maximum duty cycle of 80%, are good to around 350 HP, and that's teeming right on the upper limit. Any more power than that, and you need bigger, hence the 1000s to be on the safe side.

Secondly, I will hopefully be installing my MegaSquirt soon. Right now the Sunfire is my daily driver, and until I pick up a truck, I can't have any downtime with the car.

Third, the car was not running lean. It was running rich, pig rich, too rich. As soon as the car saw a decent amount of boost the AFRs dropped to 9-ish (which is not something to brag about), and at extreme points, started to spit out percentages. When an Innovate WBO2 starts to read percentages, that means that Lambda is greater than 6 (which equates to an AFR of 88.2:1). This obviously doesn't make any sense, and to confirm this, I contacted Innovate. They stated that the gist of what is happening is that the car is running so rich at that point that the WB02 can't comprehend it and just spits out nonsense. For the record, any time I've ever seen it read percentages, I immediately back off the throttle.

Fourth, the car is currently in the tuning process. These aren't settings that I've had for some while, or that I've just accepted and drive around with. I'm at the point of having almost everything in this car that's going to be in it, and subsequently, figuring out optimum settings.

Fifth, being that car is in a tuning stage, I never drove it that hard (as hard as I did at the track). Yes, on occasion, I somewhat leaned into it and had noticed similar results, and that's what I was trying to get rid of/thought I had got rid of. Hell, I had the car up to 19.8 during one night of tuning with not even a hint of an issue (this was not intentional as I was tuning the boost controller and the limiter decided not to "limit" my boost). As for that instance, every now and then things fall into the right place at the right time. This is why we have the word "anomaly".

Sixth, I wasn't purposely "chancing" anything. I didn't head out to the track with the mindset of, "Let's see how much $hit I can put this car through before I really mess things up." I just wasn't thinking about everything correctly, plain and simple. Reason being, the car had always run rich, so rather than think, "Hey, my injectors might be stuck wide open", I was trying to figure out why I had too much fuel, targeting the FMU. Alternately, the problem was always occurring at 4000 RPMs. So, the basics of what I had to work with were, "My AFRs are way too rich, and something is happening at 4000 RPMs".

Seventh, I have since tunned the car to run super-safe LO settings of 5 PSI, and a HI setting of 10 with a 20% boost reduction if it happens to see 10.1. I have not however, had the car past 5.3 PSI since.

In the end, I'm kicking myself in the ass for not taking duty cycle into consideration. Even more so, as I'm also a tattoo artist, and duty cycle is one of the main properties of tuning your machine (as in, if the needle hangs out for too long in it's cycle, depending upon the speed at which you tattoo, you may be "dragging" the needle through the skin as you move). Add to that the fact that I ultra-baby my car. I can guarantee that I check my AFRs more often than any two people on here combined (no, I'm not stating that I'm some kind of hero, I'm just emphasizing). I pretty much check over the entire car every single night to the point of "unnecessary" (just ask my girlfriend). That is why, aside from altering the boost levels, I have not really touched anything since having the car at the track. I just wanted to actually sit down and think of what the issue(s) may be, and then figure out what path I'm going to take as far as solutions and tuning. $hit, for all I know, the injectors might not even be the primary heart of the issue (thought obviously they need to be upgraded regardless) and it still could be some of the other ideas (MSD, Blazer pump, etc., whatever...).

The bottom line is: Yeah, I F'd up, and I comprehend this more than anyone else. The car's getting monster injectors, my MegaSquirt installed, and an HPTuners dyno tune. End of story.

Thanks for any help offered.

Tuning stages? You took it to the track on a half assed fueling setup.

For 350hp you don't need 1000cc injectors... 750cc will be fine up to 380ish horsies. You should also be actually happy that you were running rich, when I read up there that you were doing 13:1 a/f in some parts, that worried me. Personally I'd advise tuning your car to around 11.7-12.3 : 1 a/f's to be safe and still make plenty of power.

As everybody is saying get rid of the tiny 320cc injectors, that are probably burning themselves out from you making them run so hard and clip.

While you're at it, start saving money for a good clutch, you'll need it if you plan on pushing the power that your setup is capable............................... with the right tuning of course.


-Trailblazer SS - not so custom 6.0L - custom intake - custom tune
- (1) 2.4L on an engine stand (1) blown trans (2) good quad trans (1) eco trans = party

Well, I'm more than done explaining the tuning, AFRs, injectors and $hit like that.... Everything wasn't so cut and dry, but regardless, I know what it was when it was, and now it's going to be 1000s, my MS, my MSD and HPT.

As for the clutch, I was previously running a SPEC Stage 3, then my Isuzu decided to take a dump, so it was replaced with a Getrag and SPEC Stage 2 (the clutch came with the used transmission I bought). I've commented before that I have nothing positive to say about the Stage 2, and want at least a Stage 3 back in there (which is supposedly being provided by a friend here on JBO sometime this winter).

try SPEC Stage 3+................ there's not much to explain, you went to the track and ran what you ran by not going out with a proper setup.


-Trailblazer SS - not so custom 6.0L - custom intake - custom tune
- (1) 2.4L on an engine stand (1) blown trans (2) good quad trans (1) eco trans = party

Have you owned/driven a SPEC Stage 3? If so, in comparison to the "+", is there a commanding difference, or is it negligible?

Tell me everything you know about your fuel pump, your fuel pressure, and injector size... FUEL FUEL FUEL... just a thought, it was my issue again tonight, and I have a 255 intake and a 255 inline about 3" from my fuel rail.. DAMNIT


HP Tuners | Garrett T3/T04B | 2.5" Charge Pipes | 2.5" Downpipe | 650 Injectors | HO Manifold | Addco front/rear | Motor Mounts | HKS SSQV | Spec stage 3 | AEM UEGO Wideband | Team Green LSD | FMIC | 2.3 cams | 2.3 oil pump swap | 280WHP | Now ECOTECED

HELFENBEIN wrote:Have you owned/driven a SPEC Stage 3? If so, in comparison to the "+", is there a commanding difference, or is it negligible?

I've had the stock GM clutch, a SPEC stage 3, and a Clutch Masters twin disc.

The SPEC stage 3 and 3+.. the differences, one is technically able to hold more power than the other.

stage 3 I think is 400ft lbs
and stage 3+ is like 450ft lbs


I killed a 3 with three dyno pulls of 432hp 424tq, two pulls on the highway, and it died on the first run on the drag strip.


-Trailblazer SS - not so custom 6.0L - custom intake - custom tune
- (1) 2.4L on an engine stand (1) blown trans (2) good quad trans (1) eco trans = party

sorry to hear about your problem. I really hope you can get it sorted out. And when you do, make sure to post up some kick ass numbers!!!

Later



2004 Cavalier
13.2@105........
Mods...
BFG Drag Radials
Saab Turbo kit
2.5 exhaust, w/cutout
Spec Stage 2+ Clutch

SpyhunteR wrote:I killed a 3 with three dyno pulls of 432hp 424tq, two pulls on the highway, and it died on the first run on the drag strip.

So in other words, what you're saying is, F the 3 and go with the 3+...?