need Ford 30# injector info, trying to fix jerking/bucking while cruising

[AdsoYo]

I've recently completed the 24x conversion for my LT1. It runs pretty well except it jerks/bucks while cruising slower than 60mph. I dialed in my VE table with the help of this guide: http://gmtune.ru/hptuners-tuning-guide. LTFT's are +/-5 at all times which is pretty exciting. It's nice to see some form of progress. The jerkiness was still there so I made some changes to the injectors. With the help of calculators around the internet I adjusted flow rate vs. kpa, offset vs. volts vs. vac, and short pulse adder. After all that the jerkiness was still there, it was just... different. At this point I think the solution lies in the injector calibrations.

Does anyone have or know where to find info for Ford 30# red tops (the fat ones/ older ones). I would love to be able to compare my numbers to someone else.

This has easily been the most time consuming part of learning to tune. Through all my searching it seems like there was a surge of diy tuner activity about 7-10 years ago and then it all disappeared. There's so many dead links and unfinished threads from 2004-2007!

So if anyone can help me with these injector tables I could sure use it.

[edcmat-l1]

Your jerkiness is not due to, or will be solved by, injector data for those injectors. They're small enough they can be run without even modifying the stock data. Whether it's right or not, it can and will work perfectly.

How about posting a data log of the jerkiness, along with a list of you mods?

[AdsoYo]

Interesting about the injectors. Okay, a log is now attached to my first post of the car cruising in all 6 gears and ending at idle. Cruising was nice and smooth in 6th only. Car is as follows:

383ci LT1 long block built by Golen Engines
Stock heads with Golen's "3 angle valve job, bowl and slight runner porting", 50cc combustion chambers, Comp Cams double valve springs, Ultra Pro Magnum 1.6 roller rockers
Bored stock throttle body to 52mm
Comp Cams Hydraulic Roller 224/230 @ 0.50" 112 LSA
EFI Connection 24x conversion. Using 411 PCM and LS2 coils p/n 12573190
Ford SVO 30# EV1 injectors, part number M-9593-BB302
Walbro 255lph fuel pump, stock fuel pressure regulator
4L60e to T56 conversion, Fidanza aluminum flywheel, McLeod Street Pro clutch, Strange 12 bolt w/ 3.73's
MAC mids, Random Technology Cat, GMMG cat back

I've been running this engine since 2009 and it's always done this. The first tune I ran was pcmforless on the stock PCM. Second tune was from a professional on a mustang dyno. Now I'm still having jerkiness with the 24x conversion. I bought another mail order tune from pcmforless to get the car started and have since adjusted idle, ve table, dfco, injectors. Always been jerky.

[edcmat-l1]

Try this one. Those LT1s will do exactly as you say unless you pull a bunch of timing out of them in the low load areas. You may want to pull even more out. I've had them down to 30 degrees or so before they smooth out nice. Keep as much as possible, just lower it enough to smooth the jerky sensation.

The Precious temp_EH1.hpt

[AdsoYo]

Loaded your file and drove it to work. The drive was about 3.5 miles and speed limit was 35mph. Unfortunately the car doesn't feel any different. It does feel more sluggish though. The exhaust popped a few minutes into the drive. It wasn't a loud backfire but it wasn't quiet either.

Some more information that may help: No matter what file is loaded, the car has always produced faint pop noises out the exhaust while cruising or at idle. Happens every couple of seconds, more frequently cruising. Happened before with the old PCM. It was happening in the log I posted, too. It was much, much worse when I first started driving the car after doing 24x in that the pops were louder, not necessarily more frequent. I replaced 3 bad coils with dark plugs and it brought the popping down a bit. I was still using a tune from a forum member whose spark advance table was about 5-6* higher than mine across the board. We're talking 36* WOT, 47-49* cruising. Was also MAF only. I loaded my current tune in place of that one and the popping is finally back to pre-24x levels. I've always been suspicious that the popping and jerking are related. They seem to coincide.

Haven't driven it home yet so we'll see how it behaves then.

[AdsoYo]

Drove home and the sluggish feeling wasn't there but it was still jerky as ever. Timing while cruising was 33.5*.

[PST]

You're gonna need to start posting logs if you want better help. But in the mean time.. look at the areas of the timing map you were cruising in and pull more timing out as suggested above. Especially in the areas it's jerking.

[AdsoYo]

Here's a log of the car running edcmat's timing table. It was still quite jerky. Afterward I adjusted the timing down even farther in the cells where cruising happens (1400-2000 rpm and 0.20-0.28 g/cyl) to 30*. It didn't make a difference and I noticed the car was still running at 33*. I must've hit the wrong button on my laptop because it didn't save, apologies.

I'm sure there's threads on why actual spark advance isn't in line with commanded spark advance so I'll track those down. In the meantime, I found a thread talking about how leaning out the mixture in the cells where jerkiness takes place could solve the issue. How do I do that? Adjusting the VE table or MAF table won't work because the PCM will readjust the LTFT's or STFT's right?

[AdsoYo]

Did a lot of trial and error tuning today. Discovered the engine likes to cruise with spark at 39-40*. As I got closer to 30* the bucking would just get worse. Then made it up to 43* before it seemed to get worse again, so I settled on 39-40*. Then I started messing with throttle follower. It seems to get smoother the smaller the throttle follower values are. I haven't quite found the cars happy place yet, but I wanted to update since I'm taking a food break. Managed to get the LTFT's dialed in and LTIT pretty close, too. It's definitely reassuring after experiencing some success!

[AdsoYo]

Made some more progress again these last few days. Read this marathon thread about EOIT and used the Excel worksheets to figure mine out: http://www.hptuners.com/forum/showth...ereencing-what My "actual normal" values for EVC, IVO, ISP EVC, ISP IVO are 6.48, 5.88, 6.29, 5.69. I've tried multiple values from 4.54 up to 6.55 and 6.29 seems to feel the best. The bucking is still there but ever so slight. It made a noticeable difference in torque and throttle response which is nice. This probably made the most noticeable difference out of everything. Would still like to have bucking gone 100%. Can anyone tell me what the ISP stands for? Can't seem to find it's meaning anywhere.

To recap, in trying to smooth out cruising I've worked on dialing in the VE table so all LTFT's are +/-5, then re-enabled the MAF and dialed that in to keep LTFT's at +/-5. Then adjusted spark to where I was seeing the lowest MAP and feeling the least amount of bucking. (Even though it was recommended here to lower the advance, I found a few threads talking about how some LT1's do better with more advance. I guess I'm a statistic now) Now I've adjusted EOIT to finish with a closed exhaust valve (I think) instead of spraying at who-knows-when in the cycle, most likely sending a lot of fuel out the tail pipe. Adjusting EOIT didn't seem to mess with LTFT's any either.

What I'm still experimenting with is throttle follower and cracker. In my logs, throttle follower is pretty active and I can't tell yet if higher or lower values feel better. Throttle cracker I haven't messed with and it's activity pattern is a mystery to me right now. It only activates at very particular times it seems, even though the description makes it sound like it should always be on and adjusting according to speed and rpm.

I'm still hoping for some answers with my injector settings, too. I've found 3 excel calculators that all throw out different numbers and different-shaped slopes. Does anyone know what vehicles the fat red tops came stock on? There was a lone post out in the internet wastelands saying they came on Ford's turbo 2.3 but that has been a dead end so far.

[AdsoYo]

TTT. Would still like to know what ISP stands for. Also experimented with throttle cracker and got it to work. Just had to enable rolling idle. Now it behaves much more predictably and I have more control over my IAC counts, sweet! Also enabled throttle follower down to 0% tps which cured my rpm dip/ near stall when pressing the clutch. Running out of ideas for curing the jerkiness though. I've tried cruising with timing from 26*-46*, tried IAC from 30-130, tried AFR from 12.8-15.5, adjusted eoit. Is there just some super precise mixture of all these ingredients that I need to find? What else is there?

[Russ K]

Your light weight flywheel is part of the problem. Been there myself, swapped the stock one back in after 2 months.

Russ Kemp

[MikeOD]

Looking at your log, your injector pulsewidth isn't stable...which may be what you're feeling.

Try (just to test) disabling all O2 sensor feedback (closed loop as well as STFT open loop), and then disable the MAF and tune the VE. You've got VE disabled right now, and the MAF sensor numbers look like it's not in the smoothest part of the air intake stream. When you're holding ~46mph, I see your MAF go from ~4000-4500hz...that's directly driving your injector pulsewidth. If you disable it and dial in the VE...you may feel the engine react MUCH differently, and you may find it smoother...

After you've got the VE dialed in, turn closed loop back on, and see how it drives...keep the MAF disabled...if it's still smooth, look into a different intake that'll let the MAF see smoother airflow, or just keep it speed density.

You'll need to copy the high octane spark to the low octane table to do this without converting to one of the enhanced OS's.

[AdsoYo]

Your light weight flywheel is part of the problem. Been there myself, swapped the stock one back in after 2 months.

Russ Kemp

Thanks for the suggestion. However, I had a Spec lightweight flywheel when the car's engine was still stock and it was silky smooth. That convinced me this engine can be smooth with a lightweight flywheel too.

Looking at your log, your injector pulsewidth isn't stable...which may be what you're feeling.

Try (just to test) disabling all O2 sensor feedback (closed loop as well as STFT open loop), and then disable the MAF and tune the VE. You've got VE disabled right now, and the MAF sensor numbers look like it's not in the smoothest part of the air intake stream. When you're holding ~46mph, I see your MAF go from ~4000-4500hz...that's directly driving your injector pulsewidth. If you disable it and dial in the VE...you may feel the engine react MUCH differently, and you may find it smoother...

After you've got the VE dialed in, turn closed loop back on, and see how it drives...keep the MAF disabled...if it's still smooth, look into a different intake that'll let the MAF see smoother airflow, or just keep it speed density.

You'll need to copy the high octane spark to the low octane table to do this without converting to one of the enhanced OS's.

I went out to do some more logging and adjusting today. One of things I discovered a few days ago was that it seemed to like a richer mixture so before trying your method Mike, I was going to see what lowering the O2 switch points would do. I set the switch points down to 451 in the airflow modes where I cruise (10-12) and the bucking is almost non-existent. It made as much of an impact as adjusting eoit. I'll keep playing with it to see if I can eliminate it completely but even if I had to drive it in its current condition forever, I'd be satisfied.

[MikeOD]

Thanks for the suggestion. However, I had a Spec lightweight flywheel when the car's engine was still stock and it was silky smooth. That convinced me this engine can be smooth with a lightweight flywheel too.

I don't really understand your logic...a stock cam engine was smooth with a light flywheel, so a built stroker with a decent sized cam should also be smooth with a light flywheel?

That's like saying brand new tires are good in the rain, so I like bacon.

[edcmat-l1]

Thanks for the suggestion. However, I had a Spec lightweight flywheel when the car's engine was still stock and it was silky smooth. That convinced me this engine can be smooth with a lightweight flywheel too.

That doesn't make sense. A stock cam engine is smooth to begin with.

I went out to do some more logging and adjusting today. One of things I discovered a few days ago was that it seemed to like a richer mixture so before trying your method Mike, I was going to see what lowering the O2 switch points would do. I set the switch points down to 451 in the airflow modes where I cruise (10-12) and the bucking is almost non-existent. It made as much of an impact as adjusting eoit. I'll keep playing with it to see if I can eliminate it completely but even if I had to drive it in its current condition forever, I'd be satisfied.

If you lowered the switch points numerically, you did not richen it, you leaned it.

[AdsoYo]

If you lowered the switch points numerically, you did not richen it, you leaned it.

Yes! You're right that makes sense. When I was manually controlling AFR with the VCM controls, it seemed to feel better in the 12's than it did in the 15's. That got me confused. So today I tried driving with O2 switch points at 551 and it felt much worse than 451. Not sure about why, I'm just going to accept it.

I don't really understand your logic...a stock cam engine was smooth with a light flywheel, so a built stroker with a decent sized cam should also be smooth with a light flywheel?

That's like saying brand new tires are good in the rain, so I like bacon.

That doesn't make sense. A stock cam engine is smooth to begin with.

Wow. That comment really hit a nerve. 2 LT1's with lightweight flywheels aren't the preposterously unrelated items they're made out to be with that little tire vs. bacon comment. I don't even know where that came from

Yes a built stroker with a decent cam should be smooth with a lightweight flywheel. That's because the flywheel isn't the problem, it's the tune. I've had this engine for 5 1/2 years and after 1 month with hptuners it's running better than the mail-order and professional dyno tune files ever had it. There are engines out there wilder than mine that drive with stock manners. It can be done.

Nothing against Russ. Every time I do a google search about anything tuning related, a thread pops up where he's dishing out some great knowledge. A heavier flywheel with more momentum would certainly help with smoothness. I simply want to keep the Fidanza.

Also drove around in SD one more time and that changed nothing as far as jerkiness. Haven't tried messing around in OL yet. That will have to wait until this rainy weather passes. I'll update the thread.

Would still love to know what ISP stands for. Would also appreciate short pulse adder values for these EV1's.

[Jabbott]

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[AdsoYo]

Finally got a dry day to try out open loop. The car is silky smooth! I'm running open loop with MAF and it feels great. Right now I've got table values set at 0.93 for cruising and idle. My injector pulse widths are in the same ballpark as before, just not jumping around at all any more. My O2's are behaving similarly.

Concerning the O2's, I've found plenty of threads talking about what they're good for and what they aren't good for when it comes to tuning but haven't had any luck finding info on what millivolt corresponds to what lambda or afr value. It makes sense that 450-500mV would be about 1-ish lambda so would 001mV be about 0.96-ish? And 999mV would be 1.03-ish? Or with a stoich of 14.7 that would be a range of 14.2-15.2. Right now with <50kpa table values at 0.93, the O2's are showing 750-850mV bank 1 and a pretty solid 900mV bank 2. I feel like I should be shooting for 500mV, but at the same time I had a huge O2 split at 45mph below 46kpa until I fattened the 50kpa cells up to 0.98. Bank 1 was down around 050mV while bank 2 was up at 850mV. So now I'm not so sure what's going to happen if I lean it out more.

[MikeOD]

You're going to have trouble dialing much in with the narrowband sensors...this is why http://400ford.info/images/o2grph.jpg A very broad voltage range on a narrowband sensor is a very very very tight AFR/Lambda range...once you're ever so slightly away from Lambda 1.0...the sensor curve is unpredictable.

If you search more, you'll also see how greatly they're affected (away from Lambda 1.0) by both EGT and pressure...so the high and low range readings can be very inconsistent/unstable.