OK, so i'll list the motor specs below. We have recently put this motor together and cannot get it to idle. Using Crome with chipped P28 and P30 ROM. We have adjusted battery offset, changed multipliers etc, etc to no avail. Also, we have the idle set at 1,100 but the motor will not hold idle. I cannot give an AFR because the car will not idle long enough for the gauge or datalog to catch up. I know some of the items listed below should not affect idle but wanted to list them just in case. Yes this is a build for turbo. We would like to get the car broken in and running properly before installing the turbo components. Any suggestions would be great and if you need more information, please let me know.

B18 block
B16 head (PR3)
84mm bore
95mm stroke (2106 cc)
9.5;1 compression
440cc injectors
STR fuel rail
STR intake manifold
Stock map
ebay TPS (calibrated)
68mm Throttle body
PS91 coil
magnecor wires
4-1 ITR header
3" thermal exhaust (no cat)
Comp cams stage-2 turbo cams/springs/titanium retainers
+1mm valves
ported head (314cfm int/ 275 cfm exh)
Aeromotive fuel pressure regulator
-6 fuel lines / 255lph pump

Professional products damper
UD alternator pulley
Shimmed GSR oil pump
cometic head gasket
ARP head studs
adjustable cam gears
twin disc clutch
Quaife differential
GSR gears, LS final drive
DSS 5.1 axles

 

What PSI is your fuel pressure set to?

Why do you have the idle set to 1,100? I would try to get the engine started with everything in a base configuration. Idle set screw should be screwed in and then turned out just a bit.

You should be able to datalog without the engine running. Check your sensor voltages to see if one of them may be off at start up.

Along with battery offset have you tried adjusting the injector offset under the advanced fuel multiplier tab? I usually start with my offset set around 35 and go +/- from there. Adjusting it until I get my engine started and AFRs in the 15-16 range.

 

Will try and check the fuel pressure tonight, don't remember right off hand.

With the twin disk clutch and STR manifold, we figured it would be hard to get it to idle at 850 or so. I will try a lower rpm if you think we should be able to get a steady idle in that range. The main purpose I listed the info about the idle value was to make sure I pointed out that even if we raise idle to a higher value, it will not stay. We can try and hold it up manually but it will not hold electronically.

We are using an LM2 wideband, waiting on a datalogging cable for Crome. We were able to borrow a cable for one night but did not make any progress. The LM2 doesn't seem to display values until the engine is running. We should be able to correct that by changing it over to a constant 12V source, not switched with ignition. Will try this soon and update the values.

Only sensor that seems to be off is the TPS. Fop some reason TPS voltage does not show up in Crome datalog.


We started playing with the injector offset but I don't think we made an aggressive enough change from the get go. I believe we only went down to like .6 multiplier. I will try lowering that as well.

Thanks for the input and ideas.

 

from 240cc to 440cc and 1797cc to 2105cc the fuel multiplier would be 0.639. Then you click on the advanced tab (fuel multiplier tool) individual fuel corrections
Final multiplier: 0.639 offset: [**] IIRC this is where you want to make your initial adjustments. As mentioned before I usually start in the 30 range and go from there.

Engine should be up to temp and the TPS and all of the other sensors have to be working properly before you start making adjustments to the actual map.