Texas_WS6

iTrader: (9)

Here is my starting tune. I have just completed my rear mount GT-88 build and this is my starting tune. Please look it over and give me advice on this starter tune. I am realy concerned with the VE maps above 105kpa.

Here are the specs;

92 Fast TB
GMPP single plane EFI carb intake
L92 heads, ported
Iron block 408 with 10.25:1 compression
80# Siemens injectors (I used Greggs injector data for this)
Stock manifolds with wrapped SLP "Y" pipe to mandrel bent 3" wraped to turbo.
230/240 .600/.600 114 cam (I plan to change this cam latter to a 240/230 115 or 116 split)
Front mount intercooler. Methonal injection is not on the car yet.
3800 stall with 3.70 gears

I think thats the big stuff.

Thanks

LS1x2

iTrader: (11)

The VE looks pretty reasonable for getting started. It will look much different once you tune it on meth. So you have 10.25 compression, will be running more than 15psi, and you are going to start with 25* timing? I start off with 10* so I don't detonate while dialing the AFR in. You will want to disable burst knock as well.

Matt@SNLPerformance

iTrader: (1)

Are you using a return style fuel system? Also it does not look like you correctly copied Greg's data correctly. Your Offset and Short Pulse Adder tables are not right.

Texas_WS6

iTrader: (9)

I left some stuff out on the one I posted. Here is what I have now.

What is wrong with the Offset and Short Pulse Adder? Yes I am running a return style fuel system.

Here is the current tune. If all looks good I will flash it in tonight and get started tuning this thing.

Matt@SNLPerformance

iTrader: (1)

They just don't look like Greg's spreadsheet. Might be HPTuners rounding.

Texas_WS6

iTrader: (9)

Yes, I did notice HP Tuners rounded alot of the numbers. SO does the timing look ok to start or should I bring everything above 80 and over 2400 down to 10 to start with?

What does disabling burst knock do for me? Not arguing just trying to learn and trying to do this right. I realy can not afford to screw this thing up. I have a ton of money tird up in the engine and turbo build. I have spent at least $15000 on this thing.

LS1x2

iTrader: (11)

That timing is probably fine with good fuel. I just like to keep it really though in case I see AFR in the 13's while adjusting the AFR. These PCM's pull timing when they see boost via burst knock retard.

Texas_WS6

iTrader: (9)

I did not know that, so If I do not disable Burst knock it will pull the timing due to Boost, right?

Texas_WS6

iTrader: (9)

I think I have the burst knock off now, did I do it right?

LS1x2

iTrader: (11)

Yes and yes.

Texas_WS6

iTrader: (9)

Thanks. So after I am done tuning I will not want to turn the burst knock back on right?

LS1x2

iTrader: (11)

Nope. Leave it off. It is just 1 of those quirks since these pcm's were not designed for boost. Your knock sensors will still pull timing when they sense knock. Burst knock kicks in when tons of air gets shoved into the MAP suddenly.

Texas_WS6

iTrader: (9)

K thanks