How much boost can the stock ECM Map handle

[Prymal]

So i am buying a 91 with a lot of mods like a big 16g and an engine rebuild that is .020 over running 15 psi. The ECM however is not EPROM so ill have to get a standalone or convert the ECM for DSMLink. Do i need to tune the car or is the stock ECM map able to handle the increase in boost and horse power without going lean?

 

[habitatguy187]

Stock ecu map is fine until you hit fuel cut, which will happen around 14psi or so with a 16g, you'll need to get something to tune new injectors with before you need to tune the ecu for increased boost.

BTW: What are your goals with this car?

 

[Prymal]

What would be a solution to tune the injectors? i am new to the whole turbo thing

My goals are to make a fun to drive reliable street car between 275 and 300 hp that i can also autocross once in a while

 

[Bluesideup]

If you are going to reach your goals you should upgrade the fuel pump to an EVO 8 or 9, maybe a Walbro 190. You can probably get away without an adjustable fuel pressure regulator using those pumps. Then use an SAFC to tune the car.

 

[Prymal]

Alright it looks like everything should be fine, here is a list of what was done in terms of upgrades to the engine.

Engine - DSM 4G63T:
Less than 20k on rebuild .020” over
Balanced crank, pistons and rods
Balance shafts eliminated
Updated large oil port lifters
ARP head and main cap studs
New turbo – BIG 16G which is larger than stock
2.5” aftermarket upper intake pipe
TurboX’s boost controller
New high flow ported exhaust manifold w/ pyrometer port
Ported O2 housing
3” exhaust turbo back
All polyurethane engine mounts
New Radiator
New fuel pump-walbro performance high pressure/high flow
B&M adjustable fuel pressure regulator and guage
Modified air flow meter [MAF]
NGK Iridium spark plugs
Accel 8mm wires [red]

 

[lacroixdp]

Ditch those spark plugs first thing... replace them with NGK BPR6ES. Why did he do all those mods and not bother to put on the correctly sized injectors for that setup, or any sort of ECU management for that matter?

 

[habitatguy187]

Read this and this.

 

[rEclipserGST]

Read this and this.

Get Bigger Injectors, Fuel Pump, and DSMlink. You have plenty of mods and your almost ready to own.

I wish I could go back in time... I would have DSMlink by now.

 

[habitatguy187]

Get Bigger Injectors, Fuel Pump, and DSMlink. You have plenty of mods and your almost ready to own.

I wish I could go back in time... I would have DSMlink by now.

Link is cool but definitely not needed for 300whp, how about Jackal or an eprom chip which is way cheaper?

 

[jrohner]

Go with an EPROM ECU and a chip burner or emulator. It won't cost much more than an SAFC2, and you'll have control of everything.

 

[toofast82]

Link is cool but definitely not needed for 300whp, how about Jackal or an eprom chip which is way cheaper?

He doesn't have an eprom ecu he stated.
I would definitely suggest just getting one from the classifieds and burning his own chips
Used Eprom ~ $100
Ecu socketing $60
Chip Burner $30-100
Tunerpro for editing $FREE$
Cheap palm and cable ~$50-75 for logging

If you have a laptop, you could also get an Ostrich Emulator $175 and either use DsMap(jackal) or maf system with realtime control via Tunerpro RT

Either of these will give you plenty of control for well past 300whp. You can also program the computer to do almost anything and add features via hex editing.

Money saved can easily get you a wideband and maybe something else

 

[yepes281]

you can pick up an safc for 100 bucks compared to dsm link for 400.

and ide go with 650cc injectors, but nothing bigger than that casue you cant tune them with the safc.

youl easily be able to get 300hp out of your set up.

 

[Prymal]

ok, ill have to do some research on all of that stuff you just said. its got 450cc injectors right now I dont plan on changing the turbo ever so would i really need to bump up to 650cc i would think 550cc would be sufficent but you guys are the experts

 

[toofast82]

you can pick up an safc for 100 bucks compared to dsm link for 400.

and ide go with 650cc injectors, but nothing bigger than that casue you cant tune them with the safc.

youl easily be able to get 300hp out of your set up.

The only problem is he will then have no timing control. The 1g timing curve is very aggressive for pump gas with 15psi+ and will be very knock happy. He can get a few degrees by adjusting the CAS.
Many 1gs have made good power and ran very good times with the SAFC as the sole tuning device.

 

[habitatguy187]

He can get a few degrees by adjusting the CAS.

Please explain.

EDIT: Found it, turning it clockwise will advance timing, counter-clockwise will retard timing. How many degrees can you get by doing this do you know? I'd like to pull some out for piece of mind until I get a fmic.

 

[toofast82]

Please explain.

He can adjust the CAS on the intake cam. If affects the whole timing curve though. Lot of guys set it at 2-3btdc instead of 5btdc to retard it 2-3* Still not much help though when the timing is 24* at 6k rpm stock though.

 

[Prymal]

ok, sounds good i talked to the guy i am buying it from today and he had a walbo 255 with 450cc injectors and the B&M fuel regulator. he says he can run at 22 PSI with no knocking just a slipping clutch. for that reason he normally runs at 15 PSI

Used Eprom ~ $100
Ecu socketing $60
Chip Burner $30-100
Tunerpro for editing $FREE$
Cheap palm and cable ~$50-75 for logging

do i need all of these things or only some of them i am really new to the concept of open source turning software. What is ECU soketing and a chip burner. Also can i get any eprom ecm or do i have to find a specific one for the 91 tsi

 

[toofast82]

do i need all of these things or only some of them i am really new to the concept of open source turning software. What is ECU soketing and a chip burner. Also can i get any eprom ecm or do i have to find a specific one for the 91 tsi

You should be fine with any eprom 91-94 TURBO ecus. The turbo ecu has a knock board which you will need to use with your knock sensor which is why you don't want a nonturbo ecu. You should be able to use a 90eprom turbo ecu with a few changes too maybe.

The chip socket looks like this and is soldered into the ecu board in place of the old chip. Then you can take your custom eprom out very simply for code changes. Here's an example
S4 Aries 28-pin Low-Profile ZIF [S4] - $7.00 : Moates.Net
A chip burner is a eprom programmer like this
BURN2 Chip Programmer [BURN2] - $85.00 : Moates.Net
I use the burn1 which i don't think they make anymore?
You'll need chips too
C2 SST 27SF512 Chip [C2] - $5.00 : Moates.Net

Here's Tunerpro's site:
TunerPro and TunerPro RT - Professional Automobile Tuning Software

You'll need to download a definition(xdf) and bin file that are on the site. Then load them into tunerpro and edit away. There is also a hex editor feature on there where you can edit things like stutterbox, no lift to shift, phantom knock elim, etc
Heres some code changes, but things like revlimit, injectors size, deadtimes, timing, fuel, idle etc., you can just change the numerical values in tunerpro without hex editing because thats what the xdf file is for.

 

[habitatguy187]

ok, sounds good i talked to the guy i am buying it from today and he had a walbo 255 with 450cc injectors and the B&M fuel regulator.

If the car you're buying is a manual trans then you already have 450cc injectors.