Low Ignition Timing

[fmlycar]

Just had my car tuned and they couldn't put in as much as timing as tuner said an rb25 would normally take (roughly half of what he could normally add in up top)

He suggested doing a compression test, which returned a result of 145psi to 149psi across all 6.

Could an exhaust restriction be the culprit for something like this? Exhaust is unknown brand and has a mid muffler and rear cannon. Decat also so I can rule that out.

[Ben C34]

Multiple reasons, exhaust restrictions could be one.

A dud Injector can cause that cylinder to ping, as it's running leaner, and can't be picked up by a single wideband.

[fmlycar]

Brand new xspurt 1000cc injectors. So I could probably comfortably rule that out

[mr skidz]

*Pull out plugs check heat range.

maybe post a pic.

*What boost and cooler?

*Is there signs of oil on plugs from intake side of turbo

(stuffed turbo)?

* Is your base timing set correctly so all numbers on the ecu represent correct ignition advance?

Edited March 14, 2016 by mr skidz

[Ben C34]

Is your tuner retarded? Pun intended

[Ben C34]

Good jokes rely on timing

[Kinks]

Decent coils (ie splitfires) + FMIC = 4 degrees advance across the board for me.

[fmlycar]

20psi, hypergear atr45sat near new, front mount (not return flow). Coil packs had just started to break down 1500km (driving home km's) after tune. Plugs are bcpr6es gapped at 0.7, base timing has been checked over a few times now. No oil on plugs or in cooler. Runs atmo catch can not recirculating.

I will replace coil packs once they arrive. I'm still curious as to what difference removing the mid muffler would make.

Edited March 14, 2016 by fmlycar

[hypergear]

I've had similar issue on my R33 years back and it went away after I've dressed up the dump flange. Photo shown a commonly used ebay item.

Note where the overlay and reduction is, that is where the exhaust wheel sits. The Tomei dump pipes are much better engineered in that sense.

[mr skidz]

*What crank trigger are you using std Cas?

*What specific timing advance is your tuner trying to achieve & what did your car except?

Since he's surprised it wouldn't except more.

[fmlycar]

Standard cas. He said it would only take 7 degrees and was expecting 12 or more. Power does seem low for the turbo but torque seems to be ok. Car made 263rwkw and 750nm of torque. Mainline dyno.

I'll have to pull the dump off and check that out Tao. If that's the case, I will drag out the die grinder and open it up a little and make sure it's all nice and smooth.

[mr skidz]

Was it pinging? Is that why he aborted the pull?

[hypergear]

Standard cas. He said it would only take 7 degrees and was expecting 12 or more. Power does seem low for the turbo but torque seems to be ok. Car made 263rwkw and 750nm of torque. Mainline dyno.

I'll have to pull the dump off and check that out Tao. If that's the case, I will drag out the die grinder and open it up a little and make sure it's all nice and smooth.

Whats the boost curve like?

[mr skidz]

7deg is not right

[fmlycar]

[mr skidz]

Was it pinging or did he just pull up

[hypergear]

Check and dress the dump pipe flange first, then take it back for a dyno run with exhaust dropped before the cat and see if any differences are made.

Also ask the tuner to tap his map sensor before the cooler and monitor the boost pressure before the intercooler.

[fmlycar]

It's a 1500km (Adelaide to Alice Springs) drive to get back to him so I will just have to live with it for the time being. I will check and dress the dump and just get a 3.5 inch exhaust made to be certain I can rule that out.

I was told it was pinging so he got out of it straight away.

[mr skidz]

Petrol tunes running afr of 12.0 flat is too lean id fatten that up at 20psi even more so if your trying to add more timing and there is inefficiencies in the system.

[mr skidz]

Bad batch of fuel can cause all this.

Shame about the distance, you could empty the tank and try a new batch of fuel and just apply the timing in small increments and see if it will accept.

timing number sounds way too low even for that.