Big turbo anti lag tuning
So since ive went with a flashable SMEC my car is incredibly slow at spooling the turbo. I believe its timing related as ive leaned out the lower boost levels with no real change.
First and second gear are useless. the car is lazy. When it finally builds 10psi by 6500 rpm it acts lethargic. Doesn't matter if I launch off the 2 step or can on it from a rolling start.
Now, in 3rd,4th, and 5th gear it will build boost just fine and go like a rocket! I imagine its a load x rpm table that needs adjustment? Any help would be appreciated.
specs
2.5 a555
full ported head f4 cam, HE341
75lb hr,e85 flashable smec
The car runs good otherwise
Re: Big turbo anti lag tuning
Quote:
Originally Posted by
forcedfedmopar
So since ive went with a flashable SMEC my car is incredibly slow at spooling the turbo. I believe its timing related as ive leaned out the lower boost levels with no real change.
First and second gear are useless. the car is lazy. When it finally builds 10psi by 6500 rpm it acts lethargic. Doesn't matter if I launch off the 2 step or can on it from a rolling start.
Now, in 3rd,4th, and 5th gear it will build boost just fine and go like a rocket! I imagine its a load x rpm table that needs adjustment? Any help would be appreciated.
specs
2.5 a555
full ported head f4 cam, HE341
75lb hr,e85 flashable smec
The car runs good otherwise
How did you do the e85 setup? I wonder if the pumpshot is giving too much fuel?
Re: Big turbo anti lag tuning
I scaled it for 55lb injectors and fine tuned the the pump shot and fuelwot tables to make it correct. But it has never spooled fast with this set up (tune), this last Saturday was just really obvious because I was at the track. on the street I don't get on it in the lower gears usually so it wasn't as obvious.
I have leaned it out to 13.5-14.3 until 12psi where it goes to 11.5
Before (with the fwdS5) I could rev it up a few times to get the turbo going and it would launch fine and build boost quickly, now nothing helps, 2 step, reving, ridding the clutch.
Re: Big turbo anti lag tuning
Sounds timing related like you said...have you triple checked your cam and verified ignition timing with a good light?
Re: Big turbo anti lag tuning
I haven't physically changed anything on the engine since changing tunes. So I have not checked. I don't believe it would be a mechanical issue as the only thing ive changed is tune and injectors.
I was reading that a lot of the LS guys run a ton of advance down low to help spool their turbos, but was unsure on which table to adjust to do the same on mine.
Re: Big turbo anti lag tuning
Well with the slow burn rate of E85, I would expect you would need to add a great deal of timing.
Re: Big turbo anti lag tuning
Yeah, nothing new, but that's the point of alcohol - more timing or more compression or both.
Re: Big turbo anti lag tuning
Quote:
Originally Posted by
forcedfedmopar
I scaled it for 55lb injectors and fine tuned the the pump shot and fuelwot tables to make it correct. But it has never spooled fast with this set up (tune), this last Saturday was just really obvious because I was at the track. on the street I don't get on it in the lower gears usually so it wasn't as obvious.
I have leaned it out to 13.5-14.3 until 12psi where it goes to 11.5
Before (with the fwdS5) I could rev it up a few times to get the turbo going and it would launch fine and build boost quickly, now nothing helps, 2 step, reving, ridding the clutch.
11.5 AFR on e85? That seems lean. It should be closer to 7.6AFR, shouldn't it?
Re: Big turbo anti lag tuning
Quote:
Originally Posted by
ShelGame
11.5 AFR on e85? That seems lean. It should be closer to 7.6AFR, shouldn't it?
My wide band only reads to 10.0 I think anything richer than that would flood the engine completely. I know its happier at 11.5 vs 11.0;1
Re: Big turbo anti lag tuning
This is anecdotal but on my aries i had a problem that caused the injectors to go wide open and the engine wouldnt actually flood until my LC1 pegged past 9:1.
I support the timing idea. With e85 i would keep it rich in low boost and crank the timing like crazy. From what Ondonti has told me, e85 loses a lot of its knock resistance when you run it lean, which is why i say keep it rich while cranking timing.
Re: Big turbo anti lag tuning
Quote:
Originally Posted by
forcedfedmopar
My wide band only reads to 10.0 I think anything richer than that would flood the engine completely. I know its happier at 11.5 vs 11.0;1
So, your AFR gauge is still calibrated for gas, then. In that case, 11.x is about right.
Re: Big turbo anti lag tuning
Quote:
Originally Posted by
Vigo
This is anecdotal but on my aries i had a problem that caused the injectors to go wide open and the engine wouldnt actually flood until my LC1 pegged past 9:1.
I support the timing idea. With e85 i would keep it rich in low boost and crank the timing like crazy. From what Ondonti has told me, e85 loses a lot of its knock resistance when you run it lean, which is why i say keep it rich while cranking timing.
A gentlemen I spoke with said something similar but he suggested leaning it out as much as possible down low to promote faster spool. Which table would i adjust to add timing in the 1-3k range? and also, how much do you suggest?
- - - Updated - - -
Quote:
Originally Posted by
ShelGame
So, your AFR gauge is still calibrated for gas, then. In that case, 11.x is about right.
Yes, i left it on gas, more people seem to relate to it, which makes it easier on me when asking questions.
Re: Big turbo anti lag tuning
From every thing I've read alcohol doesn't mind be run much richer than gas by way of comparison. Am I the only one who has gotten a turbo to spool quickly by taking out a ton of timing early on? I don't like doing that, but it will spool the turbo.
Re: Big turbo anti lag tuning
Quote:
Originally Posted by
forcedfedmopar
A gentlemen I spoke with said something similar but he suggested leaning it out as much as possible down low to promote faster spool. Which table would i adjust to add timing in the 1-3k range? and also, how much do you suggest?
- - - Updated - - -
Yes, i left it on gas, more people seem to relate to it, which makes it easier on me when asking questions.
AdvanceFromRPM2 is the 'centrifugal' advance type function. Anything you add there goes directly into both P/T and WOT timing.
Re: Big turbo anti lag tuning
Quote:
Originally Posted by
ShelGame
AdvanceFromRPM2 is the 'centrifugal' advance type function. Anything you add there goes directly into both P/T and WOT timing.
Thank you for your quick and helpful responses tonight everyone!
Would adding to the AdvancefromRPM be the best place to start? Is there a load based timing map?
Re: Big turbo anti lag tuning
AdvanceFromMapWarmPart and AdvanceFromMapWarmFull would be the load based maps. You could try ramping the timing up quick in the low vacuum/low boost area (5inHg-5psi). You probably need to up all the timing advance tables up 5* or so anyway if you are on E85 and still running your gas timing tables.
Re: Big turbo anti lag tuning
Quote:
Originally Posted by
Force Fed Mopar
AdvanceFromMapWarmPart and AdvanceFromMapWarmFull would be the load based maps. You could try ramping the timing up quick in the low vacuum/low boost area (5inHg-5psi). You probably need to up all the timing advance tables up 5* or so anyway if you are on E85 and still running your gas timing tables.
Ok, im going to start by increasing the Advancefromrpm map 5* in the lower areas. 1700-3000 then letting it climb to peak. If I add to this table it will effectively increase the advance frommapwarm table correct? as the advancefrommap Is the "base" map everything else makes its changes from?
Re: Big turbo anti lag tuning
Its hard to say what is wrong with your car but even if everything is perfect, an F4 cam, big turbo, and E85 is not a combo to expect to go well with the same spark map as a stock gasoline setup.
Leaning out will not help tons with spoolup, I wouldn't purposely run 14:1 at 12 psi boost, that just seems like asking for motor abuse. E85 should spool MUCH faster if your tune is correct. If you are pulling timing and running lean, that would be more like 'anti antilag"
You are either going to help your turbo spool by maximizing the power of your engine (optimum timing and fueling) or pull timing and dump fuel (causes fuel to keep burning out into the exhaust manifold). I prefer maximizing HP so the car drives happy. Even if your turbo won't spool your car should feel better. Expecting your boost to solve your lack of power issues that are caused by running retarded timing is sorta crazy. You could possibly get to maximum boost sooner but your car will be slower prior to getting all that boost.
I wonder if you are using the SMEC to control boost btw.....I also like to confirm mechanical timing soundness before endless confusion ensues.
You could always build a 3.0 that doesn't need boost to spin the tires in 1st. I think expecting big turbos to perform in 1st gear is asking a lot. Very little load for how short of a time you are in the gear. Your's seems exceptionally bad which is why I wonder about your boost control. I use an external wastegate on my He341 with grainger control. Flawless.
Re: Big turbo anti lag tuning
Yeah, I've always been kind of suspicious about anti-lag that engages way before it can really spool the turbo. Seems to me like the hot ticket would be to optimize the airflow potential of the engine (which means as much timing as you can get away with and NA-appropriate AFRs) until you are at least in the ballpark of when it is possible to spool the turbo and then maybe use antilag for 500 rpm below where it would spool anyway.
If a good running engine cant spool that turbo until 3500 rpm (as an example) then a bad running engine (antilag) has no hope of spooling it at 2000. Ideally you would want to minimize the amount of time the engine was running badly and making no power trying to antilag the turbo to life and have the engine be making all the power it can until it gets to the point where anti-lag can actually make up the difference and get you into boost. If you start anti-lagging too soon you would actually be making time-to-boost worse.
Re: Big turbo anti lag tuning
Quote:
Originally Posted by
Ondonti
Its hard to say what is wrong with your car but even if everything is perfect, an F4 cam, big turbo, and E85 is not a combo to expect to go well with the same spark map as a stock gasoline setup.
Leaning out will not help tons with spoolup, I wouldn't purposely run 14:1 at 12 psi boost, that just seems like asking for motor abuse. E85 should spool MUCH faster if your tune is correct. If you are pulling timing and running lean, that would be more like 'anti antilag"
You are either going to help your turbo spool by maximizing the power of your engine (optimum timing and fueling) or pull timing and dump fuel (causes fuel to keep burning out into the exhaust manifold). I prefer maximizing HP so the car drives happy. Even if your turbo won't spool your car should feel better. Expecting your boost to solve your lack of power issues that are caused by running retarded timing is sorta crazy. You could possibly get to maximum boost sooner but your car will be slower prior to getting all that boost.
I wonder if you are using the SMEC to control boost btw.....I also like to confirm mechanical timing soundness before endless confusion ensues.
You could always build a 3.0 that doesn't need boost to spin the tires in 1st. I think expecting big turbos to perform in 1st gear is asking a lot. Very little load for how short of a time you are in the gear. Your's seems exceptionally bad which is why I wonder about your boost control. I use an external wastegate on my He341 with grainger control. Flawless.
I am using the stock can, the WG hole is ported. Boost is solid. The adjustment comes from a manual controller. Also works very well. I had no issues spooling the turbo prior to tuning change and yes I am still running the fuel ignition map, which obviously needs work (which Is what I am asking help for). Are you saying I should go back to 11.5AFR in the lower boost levels because you think it will help?
I made some changes to the advancefromrpm2 table. If it ever stops raining I will load the new changes and report back.