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Old 05-18-2011, 07:59 PM   #21
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The more load the engine is under, the lower your kpa's should be. Remember, atmospheric air is 100kpa at sea level.
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Old 05-18-2011, 08:18 PM   #22
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^^^ Umm i don't think that's correct.
At full throttle I see close to 100Kpa and at idle around the 20s-30s...
cruise high 50s-60s...

Is the engine at higher load at idle or wot?
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Old 05-19-2011, 01:25 AM   #23
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ok, good to hear your MAP is in the ballpark. 40 kpa at idle is very low as said. I had a toasted oil burner 1.8 with 45% leakdown pull better than 35kpa. So something is up there. As several noted, your fuel map is also toast. Example -Appears you have added fuel to your cranking map location (800rpm/101kpa) to get it started. That needs flattened out and the fuel added to your cranking %.

But lets talk about your timing for just a moment since you asked about cruise mpg. It is my understanding that the factory 1.6 runs 34 degrees timing for WOT. yours is way slow comparison. Given that, your 101kpa line should not be lower than 30 above 3k rpm. Increasing as throttle is taken out. your map has you cruising at 29-30. (slow) 4k cruise should be better than 35 and closer to 40 for decent economy. So how about this for an experiment. (still check your timing) Lets put a little bubble in your table table at cruise. A small bubble so you can shift rpm up or down out of it if the engine doesn't like it and get it off the road to change it. won't be with this small change, but good practice. Set your 4k 84kpa, 75kpa and 55kpa cells all to 35 degrees. Go for a drive (datalog) and see if it improves your cruise kpa at 4k. Move in and out of that speed to see effect. This will give some indication of where you need to go. in the end should be nearer 40 degrees at light cruise.

There is quite a bit more as you also indicated other tables in question. My thought is to get you started with some small things to gain that MS knowledge you are looking for and the rest will become easier.

Sorry for the long post.\

MSQ?
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Old 05-19-2011, 04:43 AM   #24
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Ah yes, I may have missed the relativity to throttle butterfly position there... My bad! At WOT, atmospheric pressure is available for the taking. Hence the 100kPa at WOT. Sorry for the bad information.
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Old 05-19-2011, 10:44 AM   #25
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oh, one more thing. I see you are running MAPdot. That can cause a lot of induced Accel enrichment if the MAP is dancing. I have found TPSdot much more forgiving to the tune.
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Old 05-20-2011, 04:59 AM   #26
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Quote:
Originally Posted by ukmiatagt25 View Post
Ah yes, I may have missed the relativity to throttle butterfly position there... My bad! At WOT, atmospheric pressure is available for the taking. Hence the 100kPa at WOT. Sorry for the bad information.
KPa is the load on the engine, the higher the number the higher the load period.

With a turbo you could in theory have 120kpa at part throttle yet an n/a car has 100kpa at WOT. Just because the turbo is at part throttle doesn't mean load is lower.
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Old 05-20-2011, 05:46 AM   #27
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Quote:
Originally Posted by richyvrlimited View Post
KPa is the load on the engine, the higher the number the higher the load period.

With a turbo you could in theory have 120kpa at part throttle yet an n/a car has 100kpa at WOT. Just because the turbo is at part throttle doesn't mean load is lower.
Not just in theory. You can easily reach 100% load at just 30% throttle on a turbo car (with a supercharger it is different due to the bypass valve). More than that and the boost kicks in. I have datalogs of a car doing 10psi on 70% throttle.
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Old 05-20-2011, 05:48 AM   #28
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Originally Posted by Reverant View Post
Not just in theory. You can easily reach 100% load at just 30% throttle on a turbo car (with a supercharger it is different due to the bypass valve). More than that and the boost kicks in. I have datalogs of a car doing 10psi on 70% throttle.
You know I don't know why I wrote 'theory' as I experienced it everytime I tuned my mates old Greddy'd MK1
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Old 05-20-2011, 10:31 AM   #29
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There is a lot of serious retardation in this thread; carefully choose what and who you listen to.
This is what a fuel table should look like:
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Old 05-20-2011, 10:32 AM   #30
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Quote:
Originally Posted by ukmiatagt25 View Post
The more load the engine is under, the lower your kpa's should be. Remember, atmospheric air is 100kpa at sea level.
Stop posting.
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Old 05-20-2011, 01:02 PM   #31
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OP, I certainly agree with Hustler on the MAP. It need serious attention. You mentioned sounding lost with the MS. Learning MS and trying to tune can be overwhelming, which is why I suggested a small adjustment to what you have (running)to see cause and effect. Frankly though you could start over with a basemap and be much better off.
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Old 05-20-2011, 02:00 PM   #32
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Quote:
Originally Posted by richyvrlimited View Post
KPa is the load on the engine, the higher the number the higher the load period.

With a turbo you could in theory have 120kpa at part throttle yet an n/a car has 100kpa at WOT. Just because the turbo is at part throttle doesn't mean load is lower.
Understood - thanks for clarifying, chaps.
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Old 05-20-2011, 11:09 PM   #33
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Quote:
Originally Posted by Justaturbo95 View Post
ok, good to hear your MAP is in the ballpark. 40 kpa at idle is very low as said. I had a toasted oil burner 1.8 with 45% leakdown pull better than 35kpa. So something is up there. As several noted, your fuel map is also toast. Example -Appears you have added fuel to your cranking map location (800rpm/101kpa) to get it started. That needs flattened out and the fuel added to your cranking %.

But lets talk about your timing for just a moment since you asked about cruise mpg. It is my understanding that the factory 1.6 runs 34 degrees timing for WOT. yours is way slow comparison. Given that, your 101kpa line should not be lower than 30 above 3k rpm. Increasing as throttle is taken out. your map has you cruising at 29-30. (slow) 4k cruise should be better than 35 and closer to 40 for decent economy. So how about this for an experiment. (still check your timing) Lets put a little bubble in your table table at cruise. A small bubble so you can shift rpm up or down out of it if the engine doesn't like it and get it off the road to change it. won't be with this small change, but good practice. Set your 4k 84kpa, 75kpa and 55kpa cells all to 35 degrees. Go for a drive (datalog) and see if it improves your cruise kpa at 4k. Move in and out of that speed to see effect. This will give some indication of where you need to go. in the end should be nearer 40 degrees at light cruise.

There is quite a bit more as you also indicated other tables in question. My thought is to get you started with some small things to gain that MS knowledge you are looking for and the rest will become easier.

Sorry for the long post.\

MSQ?
Sounds like an awesome plan, I'm still going to take things step by step though. First thing is vacuum leak, I checked with the engine warm and idling with a can of brake cleaner. Nothing caused the car to rev up, But I have an itching feeling that it has to do with the Thermostat part of the idle valve. So my next step is to pull that off and see whats up with it,

My friend with the timing light ended up being busy, So I havent had the chance to check timing, But I'm going to do so as soon as I find someone that I can borrow one from. After that, then I will start messing with timing like you suggested.

I'll also take a msq in the morning while I drive to work. DERP, I was thinking log for some reason, msq shoud be attached now.

As for cranking % that was an untuned area from when I scaled out the boosted cells. Its been mostly tuned out now, And I'm about to hand pull out the rest as soon as I finish typing this.

So my order of attack is to:

1. Turn off map dot and get tps working again asap. until then no accel enrich.

2. find that damn vacuum leak/ see if it is in fact leaking, if so, make a new afr target table and rework my fuel table. if not rework afr targets anyways and move to 3.

3. check base timing

4. test small area with more timing advance

5.???

6. Profit?

And heres my current ve table, it more closely represents yours hustler,
Not happy with it, but it seems to be running a little bit better for me until i get the timing and vacuum checked out.
Attached Thumbnails
Fuel Economy Issues, Help me find the issue?-vetable-5-20-11.jpg  
Attached Files
File Type: msq 2011-05-21_00.22.06.msq (37.6 KB, 57 views)

Last edited by Gryff; 05-21-2011 at 01:25 AM. Reason: DERP
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Old 05-24-2011, 09:31 AM   #34
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Update time. I believe I found the issue, or at least part of the issue. On the thermostatic part of the idle valve, the bit that sticks off the im, the stupid rubber seal in there is broken between the two chambers. I closed it off as best I could for the time being and my warm idle kpa dropped to an avg of 36-37 kpa. so its better but I do believe that it is still causing a vacuum leak.

I also tested a small spot of timing advance and that seemed to help out a lot as well. I'm going to leave my spark map the way it is for now, until I can find a timing light to use and check my base timing.

I also added fuel back into the 80kpa area on my target tables, but only a little bit since I still am hitting that area for the time being. But I will gradually bring that back down to where it should be.

Cruising at 70 mph now sits around 65-75kpa, so it has certaintly improved.

Only Question I have now is, does anyone know a part number, or a name for the small seal thats shaped like (I) in the thermostatic part of the idle valve? Or should I just not worry about it at this point?

Last edited by Gryff; 05-24-2011 at 09:50 AM.
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Old 05-24-2011, 11:39 AM   #35
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Sounds like great progress. Before you know it MS tuning will be old hat. Definitely finish up the vacuum leaks. Tuning to leaks is impossible. I dont have info on the seal, someone else might.
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Old 05-24-2011, 06:14 PM   #36
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Link to Gasket

This one?
I just head to my local dealer for special parts like this as they don't really charge too much over what you get online but at least there's peace of mind I have the right part.

Good find on the gasket, your idle should be sitting closer to the 30s than the 40s except if a/c is on.

I just offer a little advice on changing timing and doing 70mph drives without verifying what your base timing is... Be careful!
I doorknocked down my street and borrowed a timing light to fix timing when mine broke. Ended up meeting like minded neighbours and fixed my issue.
Man even here in australia, where we pay twice of any other country for parts, timing lights can be had as cheap as $20 so I would grab that over the next tank of gas just for peace of mind.

Good luck
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Old 05-24-2011, 06:26 PM   #37
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I agree with ampz. Driving a car without knowing timing is not wise. Atleast you arent boosted yet.. that **** would have exploded already.
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Old 05-24-2011, 11:02 PM   #38
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Quote:
Originally Posted by ampz View Post
Link to Gasket

This one?
I just head to my local dealer for special parts like this as they don't really charge too much over what you get online but at least there's peace of mind I have the right part.

Good find on the gasket, your idle should be sitting closer to the 30s than the 40s except if a/c is on.

I just offer a little advice on changing timing and doing 70mph drives without verifying what your base timing is... Be careful!
I doorknocked down my street and borrowed a timing light to fix timing when mine broke. Ended up meeting like minded neighbours and fixed my issue.
Man even here in australia, where we pay twice of any other country for parts, timing lights can be had as cheap as $20 so I would grab that over the next tank of gas just for peace of mind.

Good luck
Thanks!

Thats not the gasket, This >>Clicky clicky!
The gasket that would be there.

Yeah, idle is still upper 30s but its lower now. So im gonna fix that and it should land me where I want to be. no a/c so no worry there.
I'm gonna poke around and find a light, tired of trying to find someone i already know that isnt on vacation right now
On a good note, keeping the car in that small spot seems to really help things out, the engine sounds alot less strained, and so far the tank seems to be lasting a whole lot longer than usual. Its hard to say what right now, but certainly headed in the right direction!


Edit: ISC valve gasket?? maybe?
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Old 06-15-2011, 10:14 AM   #39
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I still cants find this gasket o-ring type deal. but the good news is that my timing is back where it needs to be, so I feel a whole lot better messing with timing knowing that it is infact where Im telling it to be.

I'm also getting approx 28 mpg now. so Ive already increased my mileage by quite a good bit. the engine sounds a lot less stressed in every situation, which is a good step in the right direction as well

My next steps are to redo my afr targets, and mess with timing a little bit, hopefully with a det can, but we will see.

heres how my spark map looks currently, you can see where the bubble is,
Does anyone have any suggestions of approximately where spark should be? In the meantime I'm going to look at others spark tables to get an idea.
Attached Thumbnails
Fuel Economy Issues, Help me find the issue?-spark-6-15.jpg  
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Old 06-15-2011, 12:18 PM   #40
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I made a spark table for Johnwag's car and can't post it since I'm at work...but it's floating around on here somehwere.
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