Running rich???

pormgb.....my injectors are the stock C5 items. I had them serviced and checked.
I tried to publish the flow report here but this forum could not process the file. (Adobe file)

Is that something that would normally be addressed with a street and/or dyno tune?

fliermike45 wrote:pormgb.....my injectors are the stock C5 items. I had them serviced and checked.
I tried to publish the flow report here but this forum could not process the file. (Adobe file)

OK, there are two sizes of LS1 injectors (26lb and 28lb), take a look at your part numbers.

I must agree with Arthropraxis.
My LS6 runs EFILive software and it took me a whole summer to tune the car, I used a Wideband to get the correct AFRs. Mail order tunes get you going but you should find someone who has a Dyno and can tune your car, LS1s need to be perfectly tuned perform properly.


GM Part Numbers
12555894 = 26lb/hr LS1
12561462 = 28lb/hr LS1/LS6

Have to play dumb here, I don't know what tune that SSP put in the PCM, I kinda wish they had left it stock and let me change it after everything was finally checked out.

fliermike45 wrote:Have to play dumb here, I don't know what tune that SSP put in the PCM, I kinda wish they had left it stock and let me change it after everything was finally checked out.

SSP's tune is probably quite standard, they just deleted a bunch of things like VATS, EGR and other emission related items, that stuff you can do your self if you have the right programming software. The trick comes with parameters that control air, fuel, timing, most of these parameters can stay stock but if you have a larger cam, injectors or TB, you will need some custom tuning.

I think you are where you should be at this point (mail order tune), I would recommend finding someone local who can do the fine tuning.

Mike,
One would think that if you had bigger injectors, or more fuel flow, for the programming your LTFTs would be in the "-"; adapting for a rich condition.
It is still possible that the tune is "bad".

Did you get a look at the IAC steps?

To recap:
2001 LS1 from C5 Vette, all sensors were stock.
Then:
New cable TB with new sensors.
New 5 wire MAF.
Injectors were serviced and flowed by Witch Hunter...report attached.
New Temp sensor.
RH Headers.
SSP Wiring modified the PCM.
GM Corvette fuel regulator....fuel pressure is 55 psi at rail.

Will see if my code reader can take a snapshot.

Also looking to find someone near 32962 who can do tuning.

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Your injectors look good, those flow rates don't reflect what you motor will see because the test pressure was 43 PSI. These are probably 26 LB injectors (at 58 PSI), you can check the GM part numbers to verify their size. Are you running the stock cam?

Engine is stock, standard cam.
SSP Wiring admit that the PCM has to be changed/modified for the pressure/flows.

fliermike45 wrote:Engine is stock, standard cam.
SSP Wiring admit that the PCM has to be changed/modified for the pressure/flows.

Ok, you probably won't need much tuning.

I sent my PCM to SSP Wiring along with Injector flow data/fuel pressure and I have just run the car long enought to warm it up. Tach shows idle as 1000, OBDII shows 780 rpm.
This is a stock LS1 from a C5 Vette with cable TB and 5 wire MAF, and headers.

Here is the data as shown on my OBDII scanner, any suggestions or comments. Thanks.

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I see your coolant temperature is at 178 degrees F which means you must be in closed loop, your LTFTs should be within -+ 5% but they show +25%. It looks like your PCM is still adding allot of fuel because it thinks your are running lean.
I've also noticed that you front O2 sensors show .230 and .445, if you scanners display automatically updates and you are in closed loop, you should see these numbers switching between 0 mV to 999 mV. If the voltages are stuck at 445mv it means you may have bad sensors or a wiring problem. It also looks like you only have front O2 sensors because OS21 and OS22 (rear sensors) show around .445mv, is this correct?

Does you scanner have an O2 sensor test?

It'll take more than a single warm-up cycle to set the LTFT values.

How do you like that Actron scanner?

Do you have a wide band O2 gauge installed? My car bounces at stoich (around 14.7) when cruising or under light throttle and goes to 12.9 or so when I'm at WOT.

Thanks guys, I'm learning as I'm an old points,coil and carb guy.

Have two O2 sensors, don't believe Actron scanner can test O2 sensors, otherwise it seems simple to use. I don't have a wideband O2 gauge.

Alternator died today, have to fix that first.

Check the power supply to all of your O2s while running.
The MAP pressure is still off, should be about 19-20 at idle. An intake leak will cause this to go down.
Your timing at idle is still high, should be 15-18 degrees
IIRC, the LTFT should start out at 0 and then change as you drive. So at 25% they are maxed out indicating a lean condition.

Mike, where are you located?

948,
I'm in Vero Beach,FL

Guess I should pulll the intake manifold.