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Just starting off with tuning holden v8 efi and at the moment just trying to get low load AF ratios to get the roughness (shaking) out of engine. 9.2 comp and 218 @50 cam. on 98 ultimate fuel.

When I put the idle and 20-100kpa maps at 11 to 1 AFR the engine runs smoother that at 13-14.7 to 1
What am i doing wrong?

Any leaner and the engine shakes around at the low load points.
I don't have a wideband yet just going by ear and feel at this point but will have a wideband next week.

I'm doing something wrong or maybe kinjflow wrong?. I set kinflow at 0.143 I got this number by taking 2lb/hr off the 775 bluetops and made it 21.90

I went 0.7875 for cyl volume. It is a 383 stroker. and got 0.143

could the trouble be from this or something else?
Thanks

no, you dont change the AFR table like that to get your fuelling, you usually leave it where it is stock as that table is the commanded afr, as in what its aiming for. it has to be 14.7 for most of the cruise areas or you wont enter closed loop fuelling. you have to put your wideband on it and then adjust your VE table until the actual AFR form the wideband matches what the commanded afr is trying to achieve.

Yes, exactly what Jayme said. Use the monitors in TP5 and set one of them to show Target AFR and Wideband AFR. Then let it warm up first of all, then set the injector rate so idle is close, then log some data at different load points and use the histogram to find out how many % to adjust other VE table cells by to bring it all in to line to actual and target AFRs are always close (with the exception of when accelleration enrichment is active and decelleration enleanment).

Also, stop now and get larger injectors, make an intercooler fit somehow, and wait for the wideband. I hate to say it but your on a path to engine ruin at the moment, its very neccesary to do the proper ground work first and make sure all the hardware is exactly right before attempting to tune.

ok thanks men.

like i said before... brand new to this and have no idea at all. about which parts of the cal to play with and what to leave alone.

I'll get some injectors and try to sort out an intercooler. theres room in front of the bullbar and down low if i have it on an angle but then the first roo will surely whack it. They always seem to know the most expensive parts to hit.lol.

There's a couple of things i can't figure out?

Antus said "set the injector rate so idle is close" what did he mean by that? is that the kinjflow? or do i need to adjust something else?

Then with the VE tables... I haven't touched them because I had the ve learn switched on and was thinking it would change all the ve's to what ever it wanted to???

So once i get the wideband etc, I just plug it in through the ecu d8 and then I might start off with a new cal from the v11 and start again. So do i just turn ve learn off and change each cell in the ve tables untill the wideband reads the same as the commanded? and that's it!... tune done.?

What stops the ve learn from changing all the ve tables after i do all that. I take it you guys turn that off if you change the cells manually?
What is the ve learn for? if i have to change all the cells myself anyway.

After i get all the ve's looking good. do i then disconect the wideband or leave it on. There's already my narrowband in the pipe does it always stay there from now on or should i take it off and just let the ecu see the wideband.

thanks

Just jumping in quickly here & not 1000% as I haven't had the chance to use the wonderful $12p yet!

But very basically you need to turn blm off to tune so no corrections are trying to override what your doing tune to what is commanded & then re enable blm so it tries to correct for any imperfections of tune or any other problems!

But I really think you need to read the tuning handbook!

I have been fixing small carby engines and bikes for around 16 years for various shops so understand a little.

Just need to get my head around tuning the air. lol.

On a carby, I set jets,emulsion tubes, floats and needles to get the mixtures i want.
Looks like here in efi... I need to change the amount of air (ve) the engine thinks it has!.

I'm sure once i get the handle of how it works i'll be alright.

So while I'm doing the ve tables... do i just leave the timing as comes in the download v11 and run with that? and just take timing out if needed, to fill the ve tables.

Once the ve tables are done, and i start with the timing/spark. does this affect the ve again much.

I dont have any knock detection. What do you guys use to detect the knock. Is there a stand alone unit with headphones you guys use or just go by torque drop off and ear on the dyno. I don't have a dyno.
If I get desperate I suppose I could rip out a diff from one of the old farm trucks, put the hose on on the brakes and burry it and use that i suppose.lol.

yeah, do the VE first, the worry about timign later. unless you change the timign heaps it wont really affect the mixture much. advancing ususally makes it just a little bit leaner. I use my mates super ping tuned hearing, and a little bit of edumacated guessing to do the timing. generally there are 2 rules at play, as rpm goes up so does spark, at the same time, as pressure increases in cylinder, spark goes down. so usually spark shoudl go up untilt he VE hits the peak of its curve (peak torque) then go down a bit at peak torque, then as the ve trails off, then the spark can skyrocket again.

generally I dont use Ve learn. imho you need to understand how to do it manually before U can do it automatically, it wont make it perfect straight away, and you need to hold it in every VE cell for it to work. I usually do a few VE load points manually with the wideband first up, idle and a few cruise, then use the tunerpro 3d graph to smooth the rest of the points out (click and drag) so its a nice even shape and close enough to drive well, then do some nice long logs and verify the rest.

The part that scares me is when the turbo kicks in...tuning for that!
It blew up almost instantly last time as soon as she came on boost.

I will need to go through the boost timing and AF and try to get it where I think it won't blow up before i hit the boost. What would happen if i set the timing and fuel on the really rich side and bugger all advance. and maybe just put the ve's at say 150 or so. would that make it safe enough to come on boost long enough to be able to get a read of the wideband so i could start with the boost ve table.

Is there a base boost map that is gonsidered really safe ?

The mistake before just cost me thousands to fix so am very nervous now. lol.

first get a vaccum/boost guage. then when you get into it, get into it just enough to stay at 0 boost, then tune the 100kpa VE's. when U are happy, set the boost commanded AFR to 11:1, then copy the whole 100kpa VE column all the way over to 200kpa. that should be a safe startign point. for spark, just copy over the 100kpa sparks and drop a degree of advance for every column of boost. but before you do any of that, go buy some 60lb injectors.

righto thanks.

I will stop playing with it and try to make up a cooler and might even build a water injection while im at it and I'll definitely get some injectors and wait till she's ready i suppose.

Just means the ute has to sit in the shed a while longer.

I have been up your way Jayme/ I went up to Lismore to some guys shed to get it all engineered to the v8.
Do you have a dyno or do it on the road?