Base tune for HAHN s16 and 680's?

[ronnies88]

Im trying to get my car to run, its been down for about a month now. I put a HAHN s16g with 2g manifold, RC 680's, SAFCll, Walbro 255, FPR, on it. But im lost with tuning the safc, i dont have a widband but i do have a datalogger, i took it down the street it pulled about 10psi and died when i let off, i brought it back turned the boost up a little and tried again it pulled about 12psi and dies again as well its completely gutless my 2.2 s10 would outrun it, i tried turning the fuel down on the afc but it doesnt idle very well it idles great with the fuel +7% from 1-4000 RPMs, i cant figure it out any help would be appreciated thanks....

 

[zhjiln]

should've gotten a wideband as a first mod.... well after the MBC....

 

[TurboTsiThatFly]

Im trying to get my car to run, its been down for about a month now. I put a HAHN s16g with 2g manifold, RC 680's, SAFCll, Walbro 255, FPR, on it. But im lost with tuning the safc, i dont have a widband but i do have a datalogger, i took it down the street it pulled about 10psi and died when i let off, i brought it back turned the boost up a little and tried again it pulled about 12psi and dies again as well its completely gutless my 2.2 s10 would outrun it, i tried turning the fuel down on the afc but it doesnt idle very well it idles great with the fuel +7% from 1-4000 RPMs, i cant figure it out any help would be appreciated thanks....

Is your Bov recirculated? cause if its not then when you let off the cars gas it will die immediately. 1g's are the most prone to do this. thats my first question. also have you done a boost leak test?

 

[JusMX141]

Keep running it like that and you'll flood the crankcase with fuel and wash your rod / main bearings, ruining your engine.

Here's a baseline- 680cc injectors are roughly 33% larger than your stock 450's; this means you'll need to create a global fuel correction factor of roughly -33% with the AFC. A wideband o2 would make this a simple task....you're going to have to wing it based on the seat of your pants.

Now keep in mind an AFC corrects based on airflow, so you're not applying a basic -33% correction factor directly to the ECU's fuel curve like you can with DSMLink. You'll be tuning somewhere between -20% and -40% on both the high and low maps to get the bugs worked out.

Adding fuel probably isn't what you want to be doing.

Is your Bov recirculated?

His profile claims he's running a Turbo XS Real F*ckin' Leaky, so I'd imagine it's not recirculated. Not to mention the giant boost leak probably existing at the base of that piece of shit where the three set screws lock and are prone to strip out of the valve's body.

 

[ronnies88]

Thanks for the help guys im aware of how dumb it is to try to tune with no wideband but what happens when your a poor bastard? .... and no the BOV is not recirculated and yes the base of them leaks because of the set screws stripping out good call jusmx but they sound cool.... im going to go try a boost leak test and turn the fuel down.....

 

[ronnies88]

still no luck, i turned my fuel down 21% across the board, done a boost leak test had 2 major leaks so i fixed them and took it down the road and it still dies, my fuel pressure reads about 38psi and i logged at 6531 RPM my INJD reads 66.4 my o2-F reads 2.73, 0 counts of knock at 5 degrees timing...... what should i do next??

 

[Fejery4491]

recirculate the bov and pull some more fuel

 

[awdjosh]

buy a wideband and tell use your AFR's at idle, 1k,2k,3k,4k,5k,6k rpms constant. remember at idle your AFR's are gonna be leaner then under throttle and even LOWER unders boost.

look up the manual for the safc i actually think it tells you the values you need to put in for a 16g upgrade with 600-700cc injectors.

 

[ronnies88]

i plan on buying a uego but money is tight so i cant afford it but i do appreciate the input so far i feel like you guys are pushing me in the right direction i took my car out today and did a couple pulls although it wasnt the fastest pulls it was still more aggressive than yesterday my logger read at 6281 RPM my INJD was 66.4% with 13 counts of knock 02 V 0.95 (kind of rich???) with 43 degrees timing

 

[mitsu_gst97]

.......43 degrees timing. yeah i dont think thats good. Im no expert on tuning but that timing pull sounds waaay out. not to mention alot of knock

 

[awdjosh]

ahahahaha holy moly knock man and timing pull. stop beating up on the car and driving it hard while your ahead or your gonna end up with a new thread "LTB: 6bolt or 7bolt block..."

 

[mitsu_gst97]

yeah man. slow it down. You need to get this figured out asap or your going to just drop your bottom end. how much fuel have you pulled?

 

[toofast82]

Keep running it like that and you'll flood the crankcase with fuel and wash your rod / main bearings, ruining your engine.

Here's a baseline- 680cc injectors are roughly 33% larger than your stock 450's; this means you'll need to create a global fuel correction factor of roughly -33% with the AFC. A wideband o2 would make this a simple task....you're going to have to wing it based on the seat of your pants.

Now keep in mind an AFC corrects based on airflow, so you're not applying a basic -33% correction factor directly to the ECU's fuel curve like you can with DSMLink. You'll be tuning somewhere between -20% and -40% on both the high and low maps to get the bugs worked out.

Adding fuel probably isn't what you want to be doing.

This is good info and should get you going!
If you have a logger, the fuel trims will help you tune
There is plenty of safc tuning info out there
http://www.dsmtuners.com/forums/frequently-answered-dsm-questions/111005-basics-tuning.html