unable to tune out ping at low (<50) map 2000-3000rpm

[jjdalynh]

 

180 is a fair amount off on CCP  What is your elevation ?? the programs are just to get you close but if your Comp ratio is that its 20+ PSI off so a tooth on the out side  retarding cam would do all kinds of crazy things .. Also that cam should have hit like a hammer out the gate for tq with a good pipe

i agree.  we are <200' above sea level.  if it was a tooth off i guess it would have to be both retarded?

[jjdalynh]

compression check shows about 180psi on both cylinders.

Is this with the TB propped open?

yes, cable driven. 

[kd]

To be sure of your numbers, check your new gauge against a known correct (or at least more correct) one. I recently experienced 2 new compression gauges that read low.

[jjdalynh]

To be sure of your numbers, check your new gauge against a known correct (or at least more correct) one. I recently experienced 2 new compression gauges that read low.

i know, that's my next thing.  this is a cheap unit from HF.

[jjdalynh]

so, if they are both off the same amount and low on gear drive cams, it'd have to be the outer gears, right?

[jjdalynh]

quick check against my shop air good regulator shows it's pretty on. 

[rigidthumper]

Equal but low would be worth checking- cost of a gasket + a little time

[jjdalynh]

seems ok to me...

[jjdalynh]

some more info, 10psi shop air into the cylinders and i can hear some air coming from the crankcase.   the rings should be able to hold that wouldn't it?

[rigidthumper]

10 PSI may not be enough to push the rings against the cylinder. Leak down tests are typically done at 100 PSI

[jjdalynh]

10 PSI may not be enough to push the rings against the cylinder. Leak down tests are typically done at 100 PSI

hm, having kind of a hard time keeping the rear wheel from moving when i apply 100psi (5th gear and brake on). 

[jjdalynh]

wet compression test yields same 180psi. 

[rigidthumper]

I use one of these:
https://www.amazon.com/Jims-USA-Mighty-Bite-Flywheel/dp/B009WD9FHU

[jjdalynh]

I use one of these:
https://www.amazon.com/Jims-USA-Mighty-Bite-Flywheel/dp/B009WD9FHU

that's pretty cool.  i suppose if i had the primary cover off i could use the locking tool for that

[jjdalynh]

outer timing marks are line up correctly, so the rear timing can't be off (unless the cams are ground wrong), front timing mark looks to be in the right place.  both cold cranking checks for both cylinders shows same results.  checked pushrod adjustments, seems correct (able to spin them on compression stroke after bleed down)....

i guess i really need to do the leak-down check to see if air is really going someplace.  what would be a good range for leak-down?   a couple percent?

[HD/Wrench]

Out of town so hard to look through all post did you post a data log  ?? Kia numbers seem way off   And yes the cam can be ground wrong as well mid machined slot in cam gear.  Went through this two years ago woods 9B. Was told impossible right up to the point I put a timing wheel on it   

Very rare though anything can happen  again  data log.  Btw did you get your free map deal ??  If so put that aside and use your OEM cal change CI reload that and see what the KPA does

Just a test  I have a idea but need an answer on that first old map is kpa and cruise OEM map idle and cruise

[jjdalynh]

fantastic.  haven't degreed a cam since i rebuilt my BBC. time to buy a new degree wheel i guess. 

i'll post up a log when i get to my pc. 

i really appreciate the help and insights from all.  this is gonna make me nuts.

[jjdalynh]

log attached.   knock retard on this tune was limited to 40kpa and above....

[jjdalynh]

and the tune....

[HD/Wrench]

Well looking at the logs and your map its clear that A the map needs to be repaired , not sure who did that but I can see how it would create issues .  If your trying to tune and have knock on that is not going to work either . as if you get ping its going to pull timing and when that happens your AFR is going to sway.

I can see if I can sort the map out , but this one is not the best , I see  many issues , send me your Stock map you pulled from the bike  gmrperf@gmail.com

Let me see what I can do also send me any and all build specs that you have , Pipe etc ,

and stop using the interpolated function is just making a mess of the map , Its clear that the map is not close and your changing cells that may not need to be altered .. I call that function the guess button at this stage .   I would rather you use the blend function if you feel the need to see it smooth .

[jjdalynh]

yeah, it is kinda the 'guess' button i know. 

originally i was street tuning with knock control set to 50.4 kpa min and my VE numbers were much lower in the cruise range, had them to within a percent or 2 run to run before it went to the dyno.  i'm wondering if the richening up of the VE was done to try and deal with pinging at low throttle?   AFR tables weren't changed by dyno operator from what i gave him. 

[HD/Wrench]

well it will give you very bad MPG , the AFR is not needing to be any where near that rich the timing tables are a total mess , I can it fighting you and not wanting to target much of anything . Timing bouncing around AFR super rich  I guess to " fix " it  and want to just bury it in fuel that is one way..  Just stating what any tuner can see .

post the map you got or email it to me that was your base file . Might be better for you to work from that , no idea if the tuner  knew what he was doing or not as this is not a map that I would send out as a complete item .

[rigidthumper]

6.2 injectors in a 107? Way too much dribble at low/mid duty cycle, will cause issues. If that's what's installed, would be worth it to switch to 5.3s and start over.

[rbabos]

well it will give you very bad MPG , the AFR is not needing to be any where near that rich the timing tables are a total mess , I can it fighting you and not wanting to target much of anything . Timing bouncing around AFR super rich  I guess to " fix " it  and want to just bury it in fuel that is one way..  Just stating what any tuner can see .

post the map you got or email it to me that was your base file . Might be better for you to work from that , no idea if the tuner  knew what he was doing or not as this is not a map that I would send out as a complete item .

One quick look and I made my decision.
Ron