Tuning for turbo

[brianjw4]

I'm planning on running a single MP t70 on an 5.3L that I'm putting in my 69 camaro. I've been reading a lot about getting started with tuning and some of the concepts are starting to make sense.

The question I've got is when tuning for a turbo, do you start with the same basics as with the NA setup? Or is the foundation of the tune that much different.

Going with EFIlive, I think.... been looking at HPTuners as well, and will be hooking up a wide band.

[johnboy1065]

I think it's a lot different. In the import turbo world (which I know about) you usually shoot for 11.3-11.5 air fuel ratios while under moderate to high boost.

while off boost while crusing around my car will usually get up into the 15-16 afr range.

[camcojb]

forced inductions tune to different parameters than n/a. Less timing under boost, and definitely richer a/f under boost. The tuning isn't necessarily a lot harder, but you have less room for error, so sneak up on it.

Jody

[brianjw4]

Thanks guys. I figure I'm probably getting over my head a little bit with the turbo, but I really want to run that setup. Been going back and forth about trying it for a few years now.

Is there a ball park timing while under boost or at least a good starting point?

[camcojb]

Originally Posted by brianjw4

Thanks guys. I figure I'm probably getting over my head a little bit with the turbo, but I really want to run that setup. Been going back and forth about trying it for a few years now.

Is there a ball park timing while under boost or at least a good starting point?

timing is relative to boost, fuel octane, engine/head design, intake air temps (intercooled or not), etc. For an LS most tuners start in the 16-18 degree range max timing at 10-12 psi of boost. This should be a safe starting point, assuming air temps, a/f, etc. are where they should be.

[Pantera EFI]

I agree with the above statements.

Two items MOST IMPORTANT:

The EMS choice, "degree based" OR "event based" ?
1. Crankshaft ignition or distributed ignition ?
2. The number of teeth on the target wheel ?
3. The ability to "detect" a missing tooth WITHOUT a CAS.

The EGO choice, wide band UEGO.
1. The LM-1 will read 1.0 richer than other brands.
2. The LS-9 UEGO will "read" correct in a high pressure exhaust.
3. Too RICH will "melt" piston tops.
Lance

[64duece]

I'd suggest getting a good plug reader and get an idea of what a properly tuned plug should look like. Reading the plugs along with the WBO2 and EGT *if available* will get you the best idea vs. trying to rely on WBO2 only.

[buds87gn]

EFI Live software should be able to record data when making passes. I would keep checks on your air fuel ratio and fuel pressure. I know with my Buick, i run 30psi static fuel pressure and additional 1psi per pound of boost. Fuel and timing are critical, and just like nitrous it can blow a head gasket quick.

Good luck