Pressure vs. TPS tuning - Thoughts, Pros, Cons?

[ateick]

I have an Autotune and POD300 to install shortly. Currently been trying to create a fuel map based on TPS by trial and error just using AFR/Boost gauges. Things have been progressing really well and sled is running great. Always room for improvement though and half the fun is trying and learning.

I'm thinking of switching over to Pressure based tuning once everything is installed. It seems to me to be an easier way for me to logically create AFR targets based on the load on the engine vs TPS.

As per the title, what are the thoughts on this direction for these Hurricane kits and Yamaha engines? Pro/Cons? Thanks

 

[Blownhard]

Hey Ateick
There’s a great video on power commanders site with regards to this topic. I’ve based my program of pressure n never looked back
Also you’ll need to cancel out your tps table and create your pressure base one.
A few questions
Stock injectors or what size ?
Fuel pump original or aftermarket?
How much boost?
Rpm your aiming for?
Gearing your running?

luc

 

[ClutchMaster]

You must be running a supercharger, and yes map based tuning is really the way to go. The pod will be able to data log so have fun!

 

[ateick]

QUOTE="Blownhard, post: 1517176, member: 30142"]Hey Ateick
There’s a great video on power commanders site with regards to this topic. I’ve based my program of pressure n never looked back
Also you’ll need to cancel out your tps table and create your pressure base one.
A few questions
Stock injectors or what size ?
Fuel pump original or aftermarket?
How much boost?
Rpm your aiming for?
Gearing your running?

luc[/QUOTE]

Thanks Luc. I watched the PC vid and that's what got me thinking.
I have a Hurricane 190 kit, 420 injectors, stock fuel pump, 6psi. 8900 seems to be WOT rpm.
I plan on changing to 21/41 next season but for now the gears are stock 24/50.

I've researched alot regarding the PowerCore software. I see your point that I'll have to switch the option from TPS to Pressure based tuning.
I'm finding that the TPS tuning is ok but because I've had to build my own tune it's difficult to gauge things just by TPS. The same 40% throttle position can have a huge range of engine load (going downhill, uphill, through deep powder, hardpacked trails, etc.) which is hard to tune for.

I had an additional couple questions:
Currently my TPS tune has a fuel map and a corresponding pressure enrichment map (the PC5 came that way when I bought it used. I'm assuming that is standard from Hurricane). Again it's hard to tune this way because there are large AFR fluctuations when you are on the edge of boost when enrichment kicks in.
- With pressure based I assume you just make one pressure fuel table?
- How many columns would you suggest for the pressure table? Current enrichment table has columns 0,1,2,3,4,6,7,8,9,10 psi.
- I would think the final table should probably be in kPa and should have more columns in vaccum?
- Would you happen to have a target table to share?

Thanks
Nick

 

[ClutchMaster]

QUOTE="Blownhard, post: 1517176, member: 30142"]Hey Ateick
There’s a great video on power commanders site with regards to this topic. I’ve based my program of pressure n never looked back
Also you’ll need to cancel out your tps table and create your pressure base one.
A few questions
Stock injectors or what size ?
Fuel pump original or aftermarket?
How much boost?
Rpm your aiming for?
Gearing your running?

luc

Thanks Luc. I watched the PC vid and that's what got me thinking.
I have a Hurricane 190 kit, 420 injectors, stock fuel pump, 6psi. 8900 seems to be WOT rpm.
I plan on changing to 21/41 next season but for now the gears are stock 24/50.

I've researched alot regarding the PowerCore software. I see your point that I'll have to switch the option from TPS to Pressure based tuning.
I'm finding that the TPS tuning is ok but because I've had to build my own tune it's difficult to gauge things just by TPS. The same 40% throttle position can have a huge range of engine load (going downhill, uphill, through deep powder, hardpacked trails, etc.) which is hard to tune for.

I had an additional couple questions:
Currently my TPS tune has a fuel map and a corresponding pressure enrichment map (the PC5 came that way when I bought it used. I'm assuming that is standard from Hurricane). Again it's hard to tune this way because there are large AFR fluctuations when you are on the edge of boost when enrichment kicks in.
- With pressure based I assume you just make one pressure fuel table?
- How many columns would you suggest for the pressure table? Current enrichment table has columns 0,1,2,3,4,6,7,8,9,10 psi.
- I would think the final table should probably be in kPa and should have more columns in vaccum?
- Would you happen to have a target table to share?

Thanks
Nick[/QUOTE]

You really should use both tables when tuning. I’m assuming you have the PTI map sensor? Easy to tune using pressure based tuning. Set it up like the tutorial shows and then run some data logs, then you can figure out where your rich or lean and change your fuel percentages in the pressure tables.

 

[ateick]

You really should use both tables when tuning.

Thanks ClutchMaster. Yes I have the PTI.

When you say I should use both tables for tuning what do you mean by that? I'm foggy on that point. From what I understand from what I see of the Hurricane map I've been adjusting I currently have in the Primary Module a TPS fuel table running and a Pressure fuel table that supplements fuel into the the system when I go into boost conditions. If I change to a pressure only based tuning shouldn't I only need one table?

I have an Autotune to install as well so it should be fairly easy to get this thing fine tuned once I create a base pressure table.

 

[ClutchMaster]

Thanks ClutchMaster. Yes I have the PTI.

When you say I should use both tables for tuning what do you mean by that? I'm foggy on that point. From what I understand from what I see of the Hurricane map I've been adjusting I currently have in the Primary Module a TPS fuel table running and a Pressure fuel table that supplements fuel into the the system when I go into boost conditions. If I change to a pressure only based tuning shouldn't I only need one table?

I have an Autotune to install as well so it should be fairly easy to get this thing fine tuned once I create a base pressure table.

You have two tables for fuel, pressure and throttle. Both should be in effect and the tps map should be pretty close to zero, most important are your pressure tables. You need too expand your tree so you can see the present settings.

This is my tps table but it’s for three extra injectors so it has radical changes you wouldn’t have. The only turn on when into boost, yours are different and it affects off boost also.

This is my pressure table that is in psi above atmospheric, since the don’t even turn on until your into boost. It uses the original computer pulse width as a base so that’s why it is actually subtracting fuel until around 13 pounds of boost. Your table would go into vacuum but the table would mostly be right around zero if you want to run the stock afr in off boost areas.

Go in here and open your pressure tables up, I know you have them.

This is where you set up the tables and make changes

Be careful don’t change any numbers already in the setup page. This will mess up The whole map. I’m sure you have them up to 15 pounds of boost.

I should note that these tables only control a set of extra piggy back injectors, not the stock ones. Tables will be much different than yours.

 

[ateick]

Awesome! Thanks Clutch. That's the piece of the puzzle I was missing. I didn't understand that you still need to have that throttle table as well as pressure table.

My plan will be:
Create a throttle table that is basically zeros.
Create a pressure table. It will be taking away alot of fuel in vaccum because of the larger injectors.
Add fuel as boost increases.
Once I have a base map I'll run Autotune for pressure to hit the correct AFRs.

Thanks again!

 

[Blownhard]

Hey Ateick
I’ve got just your setup and I’d consider a map based of 13 columns being your running 6lb boost and start @ -6,-5,-4,-3,-2,-1,0,+1,+2,+3,+4,+5,+6. Then you can set your afr based of boost pressure. I’ll up load my recent map that has auto tune enhancements for your convenience and a good starting point for you.
I to run 430 injectors but have msi external fuel pump this setup is 26% larger then stock injectors and hence the reasoning of -26 on start up this allows her to idle @1500 rpm no mater if it’s cold or mild.
The issue I have is witch one do you correct when you have issues TPS or pressure base
It’s like chewing two pc of gum at once and trying to keep them separate
Dynojets PTI Stan’s for pressure temperature input. Why go old school when you have the technology.

When based of pressure make sure
1. Set your atmospheric pressure based off your riding elevation
2. Set your pressure configuration
3. Set your pressure table configuration form -6 to +6
4.set you afr values based of pressure

this is where it gets easy to figure out the more boost the richer your afr and if considering auto tune you’ll need to select either
Pressure based tuning or tps not both.
Ill see if I can upload my complete set for u to try later this evening.

luc

 

[ateick]

Once again fantastic info! Thanks Luc. I'll look for your upload.

Hopefully this thread is helpful to people in the future as well. I found it was difficult to find any well documented info that explained how to do some of this stuff

 

[Blownhard]

Ateick

This is my latest map with trims not excepted yet
let me know if you can upload this

luc
MAP table
09 nytro xtx
430 injectors with external MSD fuel pump
no head shim or head studs plug gap .018
power commander & auto tune
6 lb boost @ 8600 rpm
91 octane with 4 oz of torco accelerator
ams afr, boost & oil temp gauges
primary
stm super tips weights with one 7 gram washer & 4 steel washers on heel with white spring
secondary
8bv51 helix with green spring @ 1&6 twist

 

[ateick]

Got it luc. I'll look it over tonight.