lean cut in 3rd gear...

[Razathorn]

Quick question RAZATHORN:

My original KAL that was tuned on the dyno showed the type-s gear ratios. I changed it to the correct RSX base one. Is that only for datalogging to make sure it properly shows which gear i'm in? Or does it in fact effect the tune in a way?

The gear ratios help the ecu determine what gear it's in since it doesn't have a gear sensor -- I think ;). I think if these are wrong, any boost per gear and gear correction stuff will be wrong. Hopefully hondata can answer that one for sure.

EDIT: ok after doing some reading and searching, I'm starting to think i'm overboosting. I did say this was originally from partial throttle to WOT. As this happens the boost guage flutters at just over 10psi. The stock MAP sensor is good to 10.5psi according to Hondata so i'm not seeing how high it's really spiking. I think this spike is the really lean and causes the cut.

Sounds possible -- if the map tops out, it will not use any more fuel as boost goes higher -- you should check a datalog to see if it is indeedl lean. In theory, you can just add more fuel, but, I would either limit the boost or get a new map sensor.

Now if this makes sense to you guys how do I get the boost to go no higher then 10psi? Boost controller? or go for a 3 bar MAP sensor that can read higher boost?

What spring do you have in the waste gate?

Wayne

[kornsined]

I believe Greddy's stock spring is 8.5psi. With the 3" exhaust I usually would hit 9psi in the summer but now it's hitting higher then settling down back down to 9psi. 3rd gear is the worst. I've seen it spike to 11psi.

Edit: Weird. I just figured out how to change the MAP to display boost psi and all my datalogs and they all say I hit 7 psi MAX. Strange since my boost gauge reads differently.

[Razathorn]

I believe Greddy's stock spring is 8.5psi. With the 3" exhaust I usually would hit 9psi in the summer but now it's hitting higher then settling down back down to 9psi. 3rd gear is the worst. I've seen it spike to 11psi.

Edit: Weird. I just figured out how to change the MAP to display boost psi and all my datalogs and they all say I hit 7 psi MAX. Strange since my boost gauge reads differently.

Whoa... you only hit 7 in your datalogs? Hrmm. Might be handy to swap maps with somone else. If your map sensor is reading low, it certianly would run lean. Where is your boost gauge tapped in at?

Wayne

[kornsined]

really :shock: hmmm. I'll have to check on the boost gauge since i didn't do the install.

[Razathorn]

really :shock: hmmm. I'll have to check on the boost gauge since i didn't do the install.

Here's the deal. I'm not a turbo expert, not even close. I've tuned a turbo rsx before, and tuned my s/c rsx as well. I'm confident in my abilities and successes but I'm not a professional tuner or installer and certianly am not where the bucks stops on asking questions. What *I* think might be happening is you may be reading boost for your gauge before the intercooler -- the boost that the motor sees, which is cooler, and potentially less psi, is read by the map sensor on the cold side of the intercooler.

Wayne

[kornsined]

that makes sense since. i'm pretty sure I seen the line hooked around the BOV which is before the intercooler.

here's the pic:


see the clear line T into the bigger blue line

[Hondata]

1. Always read boost from the manifold.
2. Boost gauges are inaccurate on a good day.
3. Boost gauges are even more inaccurate at elevation since they do not use a absolute vacuum reference.

[kornsined]

thank you Hondata. The max boost i've hit on my datalogs is 7.3 then. I think I'm just going to have to re-tune. Maybe keep my previous KAl for summer and get a re-tune for winter.

BTW I double checked and my restrictor plate on the turbo is not installed. That's not the reason for hitting only 7psi. I guess I have the 6.5psi stock spring.