chief455

iTrader: (21)

I am trying to correct my cars tune and want to understand the tables better. I am new to tuning a PCM
In my 30+ years building old cars the key has been research, reading and looking at known good running combinations.

Anyone offer to share their tune (similar to specs below) please pm me.

I'll just be asking for your specs and give you my email

Or, if you want to look at my tune to evaluate it - let me know.

The issue is it goes very rich at high rpms / under boost.

thanks

95 f-body
383 well built forged blower bottom end
9.3:1
ported LT1 heads
227/239 @ .050 .560/.577 lift, 114 lsa/110 intake c/l
Siemons Deca high imp 60lb injectors
58mm BBK
Walbro 255
SLP 1 3/4" mid lengths
y-pipe, 3" catback
DISC twin intercoolers
12 rib, 12lb pullies
neal Chance 3600 stall, TH400
9" 3.75 gear
315/35/17 nittos

MEAN LT1

iTrader: (2)

Have you data logged it yet to see when exactly its going rich?. Also are you running a speed density tune or still running a maf? Im assuming no wide band right?

chief455

iTrader: (21)

I am trying to get my cable to read my PCM - no AFR gauge in the car yet.

MAF, yes.

On a dyno with wideband the car was running ~ 14.2:1 up to around 3,000rpm then under a WOT pull A/F ratio dropped from 5100 rpm = 10:1 to 5800rpm = 8.8:1 with ~51psi fuel, 10.9lb boost


I would like to see how other similar builds have their tables set up - just as a learning tool. I read tons of 'how to tune' things, but actually comparing numbers helps me see the picture.

gregrob

iTrader: (8)

You need to get a mail order tune from Moehorsepower and start from there. He knows what he is doing with a boosted LT1.

It's probably going dead rich due to losing control of the fueling under higher boost. You can go 2 bar, althought with shitty resolution.

chief455

iTrader: (21)

Actually this car was successfully dyno tuned before I bought it. A few mechanical things have been changed and now I am here.

I don't think it is too far off in most areas.

I am open to your idea, guess I will end up on the local dyno again to verify results. A few others brought up 2 bar, but with more complicated tuning involved.

I was hoping to see other boosted 383 cars VE, WOT etc. tables just to compare.