Pro Stock John

iTrader: (34)

He was waiting for the harness the last time I heard.

I am not worried about cold start.

Plan B

[quote]Originally posted by Pro Stock John:
<strong>The other school of thought is the VE Table tuners. VE, however, is a MAP based function, and is seemingly MAF independent. However, these are the experimenters who are doing this. It *works* on LT1 cars. The code hackers say that VE changes
will not result in any operational changes, but the experimenters are (mostly) showing otherwise. Will the LS1 work the same? </strong><hr></blockquote>

Yes. My car runs no MAF. It's perfect.

ChrisB

[quote]Originally posted by 66ImpalaLT1:
<strong>Chris, I think spark is mapped by RPM and a Calculated Load Value on the LS1, not strictly a kpa from the map sensor.
</strong><hr></blockquote>

Yep, doh! Anytime I say MAP or KPA or something above replace it with calculated load value.

Chris

ChrisB

Four main areas


idle
part throttle
WOT
warm up (pre-closed loop)


Part throttle is easy - I would shoot for -4 or so % on the l-trims. If the pcm acts like the LT1 then if you have + l-trims at part throttle you may have fuel added in at WOT - and the amount will change depending on what your l-trims are, etc. 0 percent is perfect, but inreality it will fluctuate, and the goal is to keep it from becoming positive - hence the negative number.
Timing wise you are generally going to have to just use trial and error - check your plugs also. Chritian Milliard had a spreadsheet awhile ago where he attempted to use MAP readings as an indication of engine vacuume and would compare it for 2 runs to determine if timing increased vacuum. This should work in theory, but would also be a bit invovled, since you should only make small changes at time. Good idea though.


Idle
Get your car idling well first - drilling a hole in the TB, whatever. Make sure with the AC on your iac motor isn't maxing out in hot weather - that's the number one thing to look for. Then you will can only really adjust spark at idle - do this and watch your map sensor readings. Make sure your car is fully loaded - it's easy to get a high timing stable idle under light load that just absolutely craps out when the AC is on.
If you go open loop idle or some other trick then you can adjust fueling also. 99% of the time the cars like to be richened up a bit at idle.

WOT
This is going to be PE vs. RPM and your timing tables (I normally use 90-100kpa to represent WOT). I would leave the factory timing in there to start and concentrate on the fueling - use a wideband o2 and check your plugs. Once you have that down (shoot for richest at your torque peak then slowly lean it out) experiemnt with the timing. You may have to go back and change your fuel again but it shouldn't be too far off.
If you are on a dynojet watch out for going to lean/to much advance - the inertial load is equivalent to about a 2800lb car, so your motor will be much less loaded than it would at the track.


Start-up/pre closed loop
Check out your open loop AFR. Don't go to lean though -the motor needs to be run a bit rich when it is cold.


Chris

Cmarsh93z

Good informantion! I had a trial by fire with Ls1 Edit yesterday......got it installed @ noon, tuning cars by 1pm <img src="gr_stretch.gif" border="0"> Everything is pretty straight forward....I just think we need a forum so we can share tricks and hints on how to tune the best.

Chris

QUASAR

iTrader: (6)

Just got done watching a LS1 edit tune a car at a local shop here in MI. 99 SS M6 with a lid, cutout, ported MAF, plugs & wires gained 32.5 hp and 29 ft/lbs at the wheels with a good tune. This stuff is great! They played with the software to get the a/f right across the rpm band and not just the peak power increased but the whole curve showed a big improvement, 50 ft/lbs in some areas! Many many things you can do with this and i cant even mention.

Throw your translators away!! <img src="gr_grin.gif" border="0"> <img src="graemlins/burnout.gif" border="0" alt="[Burnout]" />

gwj

What was the before/after HP??

strife

does it provide a real time tuning capability ?

strife

gotta answer from ken on the real time stuff...
no

QUASAR

iTrader: (6)

[quote]Originally posted by gwj:
<strong>What was the before/after HP??</strong><hr></blockquote>

before 297HP 324TRQ

after 331HP 350TRQ

<img src="graemlins/gr_hail.gif" border="0" alt="[hail]" />

SIKLS1

Orginally posted by Camaroholic
[quote]AutoTap is so **** poor for this stuff... I hate it. I can't wait until TTS introduces Datamaster for OBDII. If you've never used it, you seriously don't know what you're missing. It should be out this spring.

<hr></blockquote>
Try using Starr Performance EFIlive V5 which is OBDII
They web site is EFILive V5

Price have been reduce to $195.00 US Dollars work's for all OBDII cars, especailly the LS1 engine, which the program was base on.
Here are the Spark and Fuel off and Holden GTS
Can log 10 time faster that Autotap.
Couple of examples of the logging it can do.
Spark Map

Fuel Map

JJH98SS

iTrader: (2)

PSJ-

I know that you knew the VE/ FSAT/ DFI stuff; I was pointing out that it's not that bad of an option, given the power potential. Relatively simple (assuming you aren't super concerned with 'daily driver' stuff), given the potential. I guess I read into your post wrong; I thought you were persuing options, vice just looking for LS1edit stuff. You know how it is sometimes; you can convince yourself "that's what he said / wrote".

Have you done airflow & fuel flow analysis for your combo? That's how I built a base map for my Firebird, and it was pretty damn close (part throttle needed a bit of work, however). The math is a bit laborious, but it can also help point out shortcomings in your system (it doesn't sound like you're in danger of that).

Pro Stock John

iTrader: (34)

Car has been dynoed a few times, but I have changed a few things (straight thru muffler, bigger intank fuel pump, new air intake) and I really have no idea if my 02 readings are what I should use for track tuning since I might have a much more efficient than a stock cube motor and might benefit from running leaner.

Mike TexaSS

iTrader: (2)

Ok ive been tuning with Lt1 edit for a year now and have had great results tuning my 409 impala. Ive done it all from gears to shiftpoints to injector swaps to fuel and spark tuning.

The best way i could find to tune Fuel at WOT is the PE vs. RPm table the fuel is put in as a Precentage. Stock impala fuel tables show a extreme riching of the fuel at the upper rpms (GM does it for saftey) Well we know lean is mean so i took the stock +17% of fuel at WOT and leaned it down to -5% fuel at WOT and picked 10 RWHP with no knock! So i would start there.

I have just ordered LS1 Edit to tune our other impala SS and have fulltime FREE access to a Dyno with Air Fuel readings!! So i will begine to embark on the LS1 Edit route! I will try and post all of my dyno results. To see what really makes power. So lets make this site the place to be for LS1 Tuning. As my ultimate goal is to tune LS1/Lt1 obd2 cars my self and save the tuners of houston some Big $$$$ i mean to have the resources to built big inch strokers then to just turn around and send the PCM off to tune it at like 400 bucks a pop makes no sense in my mind! In house dyno tuning is a must NOO MORE COOKIE CUTTER PROGRAMS every car is different i mean i made about 20 RWHP over Ed Wrights tune in my Impala if thats not enough proof then i dont know what is.

Heres a pic of our LS1 Impala SS its a 382 inch SStroker!




Opps a little advertisement in the last one!

[ January 29, 2002: Message edited by: Mike TexaSS ]</p>

Mike TexaSS

iTrader: (2)

Do not tune that awsome 422 by you o2 readings i repeat DO NOT! Get it on a dyno with some real A/F readings. thats like getting a stroker and putting n20 on it and spraying it to test if you tuning is right not good. You can lean out when trying to program by the o2's but at WOT you should look for like 880 mv on the o2's and like 900-910's if your spraying a WET kit. With dry i recmond richining it even more.

Cool28

iTrader: (2)

now the race cars at phoenix are in closed loop all the time. Can ls1edit make it that it runs in a closed loop all the time.

ChrisB

[quote]Originally posted by Cool28:
<strong>now the race cars at phoenix are in closed loop all the time. Can ls1edit make it that it runs in a closed loop all the time.</strong><hr></blockquote>

Closed loop as in O2 sensor can bias the a/f mixture?

It is not in closed loop on initial startup, but that is because the O2 sensor is not up to temperature yet, so it really can't be in closed loop.

It is probably in closed loop at WOT, but learning is disabled (if LS1 follows the previous LT1 schema). But with a standard switching type O2 you can't get feedback at WOT that means anything if the a/f ratio isn't targeted at 14.7:1. The LS1 would have to support a wideband type O2 for any kind of meaningfull feedback at WOT.

So basically the LS1 is in closed loop as much as it can be, as are almost all modern cars.


Chris

sross

iTrader: (1)

[quote]Originally posted by Camaroholic:
<strong>OK, now to PSJ's question (just for giggles <img src="gr_stretch.gif" border="0"> ).

40# injectors, 60 PSI fuel pressure.

What I would do, is to start by asking - is that a 40# injector rated at 43.5 PSI? That means that at 60 PSI, its rating goes up by approx sqrt(60/43.5) 46.98#/hr.

Of course, in LS1Edit, now we have a learning curve. I see an injector size table based on intake manifold vacuum in KPA. Stock, these range from 3.62 g/sec at 5 kPa, to 3.96 g/sec at 85 kPa. Huh.

OK, taking the stock 28 #/hr rating of a '98 LS1, I get 3.53 g/sec rating.

Taking a 46.98 #/hr rating, I get 5.92 g/sec. So, what I would try and do would be to 'fit' this new base rating with the curve given. Going from something like 6 g/sec up to 6.35 g/sec in a somewhat linearized fashion.

That would get your injector sized properly. Note that you may have to tweak your injector offset.. and damn, that's one helluva table! I have no idea where to start with that one. <img src="gr_images/icons/wink.gif" border="0">

From there, then you start tackling your block learns. I would do this for partial throttle by adjusting MAF values.

For WOT tuning (AFR with a wideband), I'd use the PE vs. RPM table. It's pretty darn plain in a stock LS1, though. But it's the fuel multiplier used during Power Enrichment mode.

My ramblings probably don't make sense, but they're a point to discuss...

-Andrew</strong><hr></blockquote>

Camaroholic:

Let me make sure I understand what you're doing. I've got 30 #/hr SVO injectors on my car. I'm assuming that they are rated at 43.5 psi (anyone know for sure)? Using the formula above (sqrt(60/43.5)*30) I get 35.2#/hr which converts to 4.44 g/sec I think. So if I'm following you correctly (and my math is right), you'd suggest I use a range of about 4.40 through 4.80 in the injector size table?

By the way, care to explain the injector offset? My LS1-Edit is should arrive "some time next week" and I'm trying to get a head start.

Thanks!

chasgiv3

iTrader: (1)

LS1edit looks great. I'm looking at it as a temporary solution for my setup. However a couple of things about the two different methods of tuning.
1. The MAF can only support so much flow. After that it ceases to be functional. I believe the number is around 670FWHP or so and that's with full MAF table modifications. After that you need to perform the 2nd method.
2. The reason I'm still going with a different engine management system is due to the fact that I want the ability to tune and adjust in real-time with an on-board wideband o2 sensor. The stockers are ok for a limited range but I would'nt want to bet my hard earned work on it.

I'm looking at DFI and YES I'm still waiting on a harness. I could cut up my existing harness but I don't want to do that YET! <img src="gr_images/icons/wink.gif" border="0">

Now...as far as the multiple coil packs being an issue....that's been solved. Not a problem with an add on device.

pugs

FAST or DFI for an LS1 is not going to be had for 2000 because of the "add on device" chas talks of. Your going to need something like that new FAST ignition box to make everything work which jacks up the price <img src="gr_sad.gif" border="0">

This is some good info here. Even us LT1 guys can learn a bit <img src="gr_images/icons/wink.gif" border="0">

I just wish the lists were in a UBB type format...so much easier to follow.