Did a few logs tonight...
I didnt say i run that exact timing map, but mine is very similar (within 1-2 degrees). I was using it to make a point because I keep hearing im lowering timing to lean my fuel out. Which is not the case, I created a fuel map and im adding timing to work with that fuel map....and its not conservative timing imo.
I use 93 octane
Trav, you have said you are running 23 psi, but it looks more like 20.5 or 21 psi in your log. You have a spike of around 250 load which is likely 23 psi but you don't seem to be holding it very long.
Now, I know that's not a huge difference but considering all of the factors in play here I think we are just simply arguing 2 different points.
Your log was in 3rd, you don't seem to be holding 23 psi (only spiking there) and you are likely in slightly cooler weather than me. I tune in 4th (a difference Scott mentioned), am holding 23.5 psi or so and often run in ambient temps in the 90's (it's currently 83* at 65% humidity here at 10:30 p.m.).
If what I assume is true then I have no doubt you are running the numbers your show in the log safely. Is this in fact the situation?
Now, I know that's not a huge difference but considering all of the factors in play here I think we are just simply arguing 2 different points.
Your log was in 3rd, you don't seem to be holding 23 psi (only spiking there) and you are likely in slightly cooler weather than me. I tune in 4th (a difference Scott mentioned), am holding 23.5 psi or so and often run in ambient temps in the 90's (it's currently 83* at 65% humidity here at 10:30 p.m.).
If what I assume is true then I have no doubt you are running the numbers your show in the log safely. Is this in fact the situation?
Those logs were low 70 degree evening here in PA....I tune and log in 3rd gear and then will log in 4th and see what happens then i will tweak here and there to be happy with what im seeing in 4th gear as well. We get very hot and humid days here though, but when its real hot i take it nice and easy with my car. Plus I always drive atleast 5 min. between each log to let the car cool down so everything isnt all heat soaked for the next pull.
Whatever it is my car seems to be responding well and likes it, my knock sensor tells me so
It is very much doable. Along time ago Razolab (Bryan @ GST) showed us how to do it. He even posted logs of his car going through the gears and hitting 11.1 in the gears @ WOT.
Yeah im spiking to 23psi and holding like 22+/- for a while......im actually going to work on getting my boost set to where it peaks and holds and doesnt just spike and drop, then hold. I dont think im getting any benefit from that boost spiking, even at 24psi i was still dropping to the same load at the same rpm.
https://www.evolutionm.net/forums/at...2&d=1183586586
With ECU boost control you can control boost in 500 rpm segments. This is not possible with an MBC.
I'm not sure how you are tracking your boost levels, but for reference I run 23 psi at ~250 load as logged by the JDM MAP sensor. Your load levels look more like 20 and not 22. It's not a huge difference, but your gauge might be a couple of psi off.
Good luck getting the boost to hold. As stated above, MBC's are still fairly bad about taper. I just tuned a car using the Greddy EBC and it held boost great (23 psi spike and 21.5 to RL). I personally use the stock solenoid and can hold 20.5 to RL even with the stock cat in place. I can hold more with some VVT tweaks but the logs show power loss there ...
Good luck getting the boost to hold. As stated above, MBC's are still fairly bad about taper. I just tuned a car using the Greddy EBC and it held boost great (23 psi spike and 21.5 to RL). I personally use the stock solenoid and can hold 20.5 to RL even with the stock cat in place. I can hold more with some VVT tweaks but the logs show power loss there ...
Last edited by TouringBubble; Jul 20, 2007 at 08:42 AM.
I considered doing this as well. i might do it on the way to the track this evening. I checked 3rd last night as was showing a nearly identical curve to 4th. I'll post logs if I'm able to do this tonight. Will 2 - 5 work or would 6 be helpful to see too? I can only do 6 up to about 4500 I would think ... (Professional driver. Closed course.)
Travman,
I am surprised by the low torque numbers on your Evo IX. I run 22 psi tapering to 19.6 psi @ redline. AFR is @ 11.70 tapering to 11 by redline and timing is 3* @ peak and 10* by redline. The Gas is crappy CA 91 octane.
The log was taken on a slightly inclined ramp. The benchmark is the stock output. The car only has a TBE with a drop in.
I am surprised by the low torque numbers on your Evo IX. I run 22 psi tapering to 19.6 psi @ redline. AFR is @ 11.70 tapering to 11 by redline and timing is 3* @ peak and 10* by redline. The Gas is crappy CA 91 octane.
The log was taken on a slightly inclined ramp. The benchmark is the stock output. The car only has a TBE with a drop in.
I think your problem is the MBC. MBC's have to spike inorder to hold boost. Invest the time and learn how to do ECU boost control. With ECU boost control I can hold the boost on my car @ 22-21 psi all the way to redline.
https://www.evolutionm.net/forums/at...2&d=1183586586
With ECU boost control you can control boost in 500 rpm segments. This is not possible with an MBC.
https://www.evolutionm.net/forums/at...2&d=1183586586
With ECU boost control you can control boost in 500 rpm segments. This is not possible with an MBC.
Wow, who do you think your fooling....
BTW I bet your on stock cams....
probably for the same reason they didn't come with WB02 sensors, it isn't necessary once the engine has been tuned correctly 
but once you start modifying the car, the more info you have the better off you are, especially if you're going to utilize an extreme tuning strategy.
I'm not saying everyone needs to go out and buy an EGT sensor at all, I'm simply saying that if you're going to tune your car to air/fuel ratios that are typically reserved for race gas, you need to be very careful and it wouldn't be a bad idea to arm yourself with all the tools you can to make sure you don't have a melt down. I think most of us can agree that his tuning strategy is a bit extreme for a boosted car in this summer heat. I'd hate for a newbie to stumble upon his post and melt a piston trying to reach 12.0 AFR on pump gas.
but once you start modifying the car, the more info you have the better off you are, especially if you're going to utilize an extreme tuning strategy.I'm not saying everyone needs to go out and buy an EGT sensor at all, I'm simply saying that if you're going to tune your car to air/fuel ratios that are typically reserved for race gas, you need to be very careful and it wouldn't be a bad idea to arm yourself with all the tools you can to make sure you don't have a melt down. I think most of us can agree that his tuning strategy is a bit extreme for a boosted car in this summer heat. I'd hate for a newbie to stumble upon his post and melt a piston trying to reach 12.0 AFR on pump gas.
You know, I have to agree with Mellon here. I kind of feel like everyone is attacking him in regards to the EGT probe. I have one in my car, and yeah, I actually do look at it all the time as a "reality" check. I know that EGT's aren't the most reliable, I know they aren't a good way to tune, etc. But, what is so wrong in knowing one more thing in how your engine is running? Down here in Charleston, SC, I can see sometimes a 100*-200* difference in EGT's based on the weather here. Just by noticing that, I would make a logical ASSumption that the car, based on the weather can have a more ideal tune due to the weather changes here.
I don't see why mellon is being "attacked" (Term used very loosly) for suggesting an EGT. What is so wrong in knowing one more engine operating parameter? There certainly is no harm in knowing.
Not to stray too far off topic, but we dont need a boost control discussion in an AFR thread. There are logs of people doing this, I have some logs on a stock turbo from my car, Kreonics car, etc. Not all cars taper to 17 by redline as intake plays a HUGE role in how the turbo supplies the engine.
Last edited by JohnBradley; Jul 20, 2007 at 09:27 AM.
He didnt just seem to be suggesting to have it there to look at. He was suggesting (as it appears to me) that you tune by it. This is ridivulous when we have the factory knock sensor to tune by, WB's to tune by, etc. Mellon brought some of that on himself from all appearances.
He didnt just seem to be suggesting to have it there to look at. He was suggesting (as it appears to me) that you tune by it. This is ridivulous when we have the factory knock sensor to tune by, WB's to tune by, etc. Mellon brought some of that on himself from all appearances.
Yeah, I understand now what you mean...
I have never used mine to tune by, but I guess I got it because I thought it would be like that gage that would tell you that something is seriously wrong if you saw it go over say ~1700*. (My WOT is around 1500-1550 I think, if memory serves me correctly...) Plus, I like it because it's like how rednecks like shiney things, I like watching a few gages bounce around all over the place, even if they aren't really telling me anything! Haha! Just Kiddin!