Harrop Supercharger for 21 LC

[gluaisrothai]

I’m not sure why you would want the TC unlocked in those gears any ways

I don’t necessarily want to change those, just noting that they are not available to edit. Gears 2,3,4 are blocked from locking the TC by having the lockup speed set to 256 kph but can be made to lock if desired.

Also where to edit the gear upshift/downshift schedule for ECT is not very clear. I can see the primary schedule, and the 4-lo, but the secondary schedule is the same as primary- so that isn’t the ECT map.

 

[gluaisrothai]

Question for those with transmission tuning experience. What I would like to do is allow the additional torque available from the supercharger to allow me to hold onto 6/7/8 for longer as I get into boost in those gears (vs downshifting). Right now I can barely get to 1.5 psi of boost before a downshift occurs.

The Toyota map uses road speed vs TPS output to determine shift points, rather than torque. My thinking is to reduce the speed point per throttle position on the downshift map to allow boost in the higher gears.

Example:
Stock 7th downshift map:

Modified 7th downshift map:

Would that have the desired effect?

Thanks
Ken

 

[skrypj]

Question for those with transmission tuning experience. What I would like to do is allow the additional torque available from the supercharger to allow me to hold onto 6/7/8 for longer as I get into boost in those gears (vs downshifting). Right now I can barely get to 1.5 psi of boost before a downshift occurs.

The Toyota map uses road speed vs TPS output to determine shift points, rather than torque. My thinking is to reduce the speed point per throttle position on the downshift map to allow boost in the higher gears.

Example:
Stock 7th downshift map:
View attachment 3585066

Modified 7th downshift map:
View attachment 3585073


Would that have the desired effect?

Thanks
Ken

Either that or increase the axis data so that, at a given speed, it requires more throttle pedal angle to cause the shift to occur.

 

[gluaisrothai]

Another question. From the training docs on the VF Tuner site it is recommended to lower the transition threshold for the switch from closed loop AFR to the WOT map. I was considering lowering each set point by 5% as an extra safety buffer.

 

[skrypj]

Another question. From the training docs on the VF Tuner site it is recommended to lower the transition threshold for the switch from closed loop AFR to the WOT map. I was considering lowering each set point by 5% as an extra safety buffer.


View attachment 3585089

Open one of the TRD Supercharger tunes. They have them under the Tundra folder. See what Toyota themselves did.

You might also want to look at what their WOT Target AFR's are and compare to your stock file.

 

[gluaisrothai]

Either that or increase the axis data so that, at a given speed, it requires more throttle pedal angle to cause the shift to occur.

Aha! I didn't realize you could also edit the topline.

 

[skrypj]

Aha! I didn't realize you could also edit the topline.

Yes I believe you can.

Ideally you would do this for the Acceleration Calculated Torque to Airload table as well. If you look at the TRD tune they extend the Axis data out to like 1000 newton-meters of torque. In the case of the TRD tune, the table is actually extended and has more columns than the stock tune though, so you would have to trim out some of the columns you have now so that you can extend it.

I'd previously done similar when I was tuning my Jeep Liberty diesel. I had to cut out columns on certain maps so that I could add additional columns to the end of the map to stretch it up higher.

 

[skrypj]

TBH, I still can't wrap my head around how exactly the Toyota tuning works. Its like a weird combination of MAF and speed density tuning. I dont really understand where the calculated torque comes from.

Like on my F150 and my Jeep Liberty, there was a drivers demand map that determined the target torque based on the RPM and throttle pedal position. There is nothing like that on the Toyota tunes. ITs like the torque just materializes out of thin air or something. Which i guess might be what is happening since you can just drop a supercharger on it and it works. Like it seems to be just looking at the MAF and saying, oh, well, I am getting this much air so I need to spray this much fuel and it just doesnt seem to care how much air it gets.

On my F150, it is very precisely controlling air load all the time via the wastergates and throttle body to hit the exact torque that is being requiested. I could be at WOT in my F150 and the throttle body might only be open 30* because its trying to control airflow from the turbos to achieve the exact torque that is specified. The 5.7L just seems to follow whatever throttle opening is specified and whatever air mass it gets is what it uses.

 

[gluaisrothai]

Yes I believe you can.

Ideally you would do this for the Acceleration Calculated Torque to Airload table as well. If you look at the TRD tune they extend the Axis data out to like 1000 newton-meters of torque. In the case of the TRD tune, the table is actually extended and has more columns than the stock tune though, so you would have to trim out some of the columns you have now so that you can extend it.

I'd previously done similar when I was tuning my Jeep Liberty diesel. I had to cut out columns on certain maps so that I could add additional columns to the end of the map to stretch it up higher.

That specific table is missing on my map. Gives this error:

 

[gluaisrothai]

Here is the stock Toyota WOT AFR map:

Here is one of the supercharged TRD maps (YWF63):

Looks like the NA Toyota map is more conservative- richer.

 

[skrypj]

Here is the stock Toyota WOT AFR map:

Here is one of the supercharged TRD maps (YWF63):

Looks like the NA Toyota map is more conservative- richer.

The pics didnt come thru.

There are other compensations for AFR other than that that can make it richer. Cat overtemp protection, load based multiplier, etc.

 

[Moby]

@gluaisrothai are you on the Harrop stage 1 configuration (stock injectors, upgraded pump, modified fuel pressure regulator)? Now that VFTuners supports through '21 I'm back seriously thinking about a Harrop again but not sure if it would be best to start off in the Harrop configuration or leave the fuel pressure regulator alone, get bigger injectors and pump, and tune from there.

 

[gluaisrothai]

@gluaisrothai are you on the Harrop stage 1 configuration (stock injectors, upgraded pump, modified fuel pressure regulator)? Now that VFTuners supports through '21 I'm back seriously thinking about a Harrop again but not sure if it would be best to start off in the Harrop configuration or leave the fuel pressure regulator alone, get bigger injectors and pump, and tune from there.

So far I am stage 1 Harrop. Have not had time to move onto the next step with tuning it yet.

 

[Jason Andrews]

@gluaisrothai are you on the Harrop stage 1 configuration (stock injectors, upgraded pump, modified fuel pressure regulator)? Now that VFTuners supports through '21 I'm back seriously thinking about a Harrop again but not sure if it would be best to start off in the Harrop configuration or leave the fuel pressure regulator alone, get bigger injectors and pump, and tune from there.

The fuel pump that comes with the Harrop kit is 340LPH and enough to keep up with a stage 2.
.65cc x8 cylinders x 60mins= 312 liters per hour

In case you missed my post in the other thread...once you get a stage 1 tune you will need the 535cc TRD green injectors minimum. I did 1 step colder spark plugs as well. FWIW I have not heard of anyone with a '16+ who has used any other injector size or brand larger the TRD's and not have intermittent warm start issues. I'm one of them.

The guy who tuned my truck is also who Slee trusted to tune their Harrop SC LX. He just did a '21 HE LC and no problems.

I am 1 of 3 or 4 others he's tuned that have the start issue with other injectors- he did warm me before, but I had already purchased the injectors. Prospeed 650's, 750's, Fuel Injector Clinic 775cc, Deatchwerks 650's etc all have caused this result.

The Maggie 2650 kit includes the TRD injectors. Most everyone will say the canned tune they include is mediocre at best. It runs lean AFR's at WOT and this engine needs to run super rich to keep the rings lands cool. Definitely better to get a custom tune for more peace of mind.

 

[Moby]

I did see that about the injectors, thanks for posting that. I'm hoping that I can get away with the greens, although from what I read they are at the limit with a safe stage 1 tune.

Are you running Harrop's modified fuel pressure regulator, or did you just go bigger injectors and custom tune?

Could you share the tuner's info? Would like to see if they do remote tunes.

 

[Jason Andrews]

I did see that about the injectors, thanks for posting that. I'm hoping that I can get away with the greens, although from what I read they are at the limit with a safe stage 1 tune.

Are you running Harrop's modified fuel pressure regulator, or did you just go bigger injectors and custom tune?

Could you share the tuner's info? Would like to see if they do remote tunes.

Harrop gives directions on how to modify the stock FPR if I'm not mistaken. He had me get a new stock FPR when I had the tune, injectors, plugs done. Apparently he was happy with the setup of the shop that did the install a year before because he didn't use the new one I had one hand.

Yes, his name is Mike owner of FIGS Engineering.

 

[willstroo]

Harrop gives directions on how to modify the stock FPR if I'm not mistaken. He had me get a new stock FPR when I had the tune, injectors, plugs done. Apparently he was happy with the setup of the shop that did the install a year before because he didn't use the new one I had one hand.

Yes, his name is Mike owner of FIGS Engineering.

Mike at FIGS is the man, he knows Lexus products like no other.. When I had the ISF he was the go to, full industry leader.

I would be super copmfortable to get a remote tune from him, he used to ship his tunes to Australia for the ISF as a package.