b18c1 block, head
11.1:1 CR
ITR crank/rods/USDM ITR pistons
ITR valvetrain
01spec ITR cams (set at 0,0)
base 16 BTDC timing
ARP rods/mains/heads
240CC injectors
JDM p72 w/ Neptune RTP (using JDM GSR basemap as of now)
Motor was just built by me over the last few months…
Here is the initial start-up issue:
Primed the oil pump, built fuel pressure, brandy new plugs/wire/cap/rotor
1.–Fired up on first crank (using USDM ITR basemap with IACV disabled), sounded beautiful for about 8-10secs then died. Turned over fine afterwards but would not fire. Pulled plugs and were wet with fuel, maybe oil from unseated rings. Cleaned and dried plugs
Raised fuel pressure a bit ~45psi, switched to a JDM GSR map with no idle correction or IACV disable. Car turned over and started but immediately rev’d to almost 6K, killed it immediately.:dunno: It will restaret only if throttle is near wide open
NO fluid leaks what so ever, sounds healthy as can be. I did not compression test it as of yet, motor has never been ran so new rings=shitty comp. Idle (for the seconds it lasted) did not bounce, so I doubt vacuum leaks. Appears to be getting plenty of fuel, and air. It may be possible that oil is making it past the unseated rings and putting out the spark.:squint:
I’ll be brainstorming all day, and will reconfigure my maps before I try again tonight. No weird sounds, no CEL, just a clean cutoff= no idea. I’d almost rather hear a strange sound so I have an idea where to examine more closely
Are you sure its flooding out with fuel? If it is then I’d pull the ecu fuse/backup fuse and crank it just to get the fuel out of it, then see if it will fire on ether with the fuses back in. If it does, it sounds ecu/wiring related.
When it fires up WOT, can you get it to idle or will the revs not slow down, or does it just die? there’s no glory in disabling the iacv. If its a normal intake mani/tb setup then i’d get it to idle with the iacv.
It’s an ITB setup, so IACV is not an option. I am aware the car has very little ability to control idle as is…before the rebuild, I installed the ITB’s (run on the stock ECU) and it idled high, but not more than 1.5-2K…so the bugs with that should have been ironed out.
When it starts, it’ll rev on it’s own if it doesn’t die altogether…similar to what happens if you have a large vac leak, but I can’t find a leak…
I don’t know if it’s flooded per se, but brand new plugs pulled after one crank/run cycle were wet, and dried after being exposed to air…oil would not evaporate like that. Shining a light into the spark plug hole shows a bit of oil on the slugs…which I expect from rings that have never travelled the length of the bore other than me hand cranking it.
I see that you tried the ITB set-up on a previous motor with a stock ecu. Try a stock ecu on this set-up to help eliminate any potential physical variables with the new motor.
Also, are you tuning based off tps only or tps and map? When I tuned my ITB set-up on chrome things got a little finicky when the voltage from the tps was too low.
ahhhhh ITB’s, you should have said! Now, what are they? What are you using to set the idle on the plates?
Whenever I built my first ITB setup on my allmotor LS, i had a lot of little bugs to work out, but eventually dialed them in really nice. Its just a matter of making sure they are sync’d right and then setting the idle using a good idle map.
Forgot the most relevant info: GSX-R 1000’s 42mm plates, overall dimesions are a hybrid between Jenvey/Hayward specs for ITR’s. MAP is plugged in but may not be useful, probably do strictly TPS based maps in the real tune.
I am using Neptune RTP. For now it is just on a b18c basemap…can’t reuse the old ECU…Joe bought it. The ECU does appear to playing a role…
loaded USDM P73 map, fired right up therm died…will crank readily but not start after that
loaded JDM P72 map, cleaned plugs, fired right up and died. Open throttle fires up, rev to the sky and I kill it. It did not rev with the above map. I did not mess with tip-in or cranking fuel or anything yet.
Tonight I’ll go back to a stock USDM P72 (same as what I was running before) and give it a shot alond with vac/spark/fuel monitoring.
Why not try using the map? I street tuned my setup after hybrid tuned it w/o ITB’s and gained a ton more midrange, mostly in timing. As long as you have a good fuel curve, my ITB’s were not nearly as hard to tune as I thought based on what everyone has said.
I’d try a stock p72 like you said and see what happens. Though, if it just revs to the moon, its not like its iacv related where the idle is open… it sounds like the plates are open. Did you log your closed and wot tps readings and account for them?
I’m using the Suzuki TPS on this measured .47V closed/4.1V open so I did add that to my calibration. I’ll check when I get home, but I wonder if me backprobing it so many times may have caused a short in one of the three TPS wired and the ECU is thinking it’s WOT. The plates were closed fully though.
well if it revved to the moon once, then there is air (vac leak) getting past somewhere. I’d keep that in the back of my mind. Are you checking tps voltages at the sensor or at the ecu? I always check wires at the ecu… pop the flip covers back and prob at the pin.
Yes, had that worked out before I tore the motor apart.
Before the tear-down I installed them EXACTLY as I have them now, running on a virgin p72…idled a bit high but was fine. It was about 10 degree outside, and the car hadn’t been started in months so I expected a high idle.
Aside from internals, nothing has changed, and even then it is not a drastic change…for all intents and purposes it’s a stock GSR rebuilt into a stock ITR.
I cleaned the plugs, changed a few vac hoses, put the original base USDM p72 map into it. Fires right up, but will not stop revving.
Pullls a decent steady vacuum, 42psi fuel, timing perfect. No oil pressure light, no stumbling, nothing just runs like rape date, lol. Compression check is showing 170 psi across the board with zero break in. Datalogged a start-up, MAP values are at the way high end of things .970ish bar (high for idle anyway, last two column in my map table [unexpanded]). Not sure what to do next. I don’t want to keep turing it over…it isn’t helping the rings at all.
I re-probed the TPS, and the signal wire literally fell out of the sensor. I took it all apart and re-calibrated everything. Now it starts but idles steady at ~3K, still sucks, but better than uncontrollable revving. Vac is fine, I can’t figure out where the air is coming in. Datalog isn’t picking anything up because I’m not opening the throttle (it’s set to auto-log above 0%)