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Low compression ratio spark advance tuning?

 
Old 03-09-2019, 11:55 PM
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Default Low compression ratio spark advance tuning?

I can't find much info on tuning a low C/R engine. I know you can run more advance, but how much more? I bought a car with 8.5 C/R Wiseco's and it just feels sluggish until the boost comes on. My current map is similar to what most people run with a stock bottom end. Anybody with a low C/R engine care to provide some insight or share their spark map?
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Old 03-11-2019, 04:44 AM
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You should really get on a dyno and tune your sparkmap. How much more timing is dependable on so many factors you can't just give a number.

Upload a picture of your sparkmap so we can have a look.
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Old 03-11-2019, 07:32 PM
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Here is my spark map. It is a 8.5 compression ratio 1.6 running a 50 trim T3. I'm mostly looking to improve spool up and drive-ability out of boost. Yes, I know a 1.8 would help, but the car came with a fresh built 1.6 with Wiseco's, Manley rods and boundary oil pump, so I'm going to see what I can get out of it.
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Old 03-11-2019, 08:23 PM
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Originally Posted by PSI View Post
I'm mostly looking to improve spool up and drive-ability out of boost. Yes, I know a 1.8 would help, but the car came with a fresh built 1.6 with Wiseco's, Manley rods and boundary oil pump, so I'm going to see what I can get out of it.
You have to remember, out of boost it's a 1.6 with low compression. Pistons, rods and an oil pump don't add power, they just help with reliability.
Why don't you post a log of two so we can see how your car responds to WOT into boost?

There's only so much that can be done.. and your spark table looks about normal under 100kpa...
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Old 03-11-2019, 08:26 PM
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PS. I'll say it again as well. Best thing to do is get it on a dyno, load it up, and tune it.
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Old 03-11-2019, 08:29 PM
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PPS. Two relevant threads for you to digest relating spool data and your T3.

2554 vs T3 on a 1.6

Spool data galore megathread.

I bet you can find LOTS of great info there and help set your expectations on what your car is capable of.
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Old 03-11-2019, 08:48 PM
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Originally Posted by SchmoozerJoe View Post
You have to remember, out of boost it's a 1.6 with low compression. Pistons, rods and an oil pump don't add power, they just help with reliability.
Why don't you post a log of two so we can see how your car responds to WOT into boost?

There's only so much that can be done.. and your spark table looks about normal under 100kpa...
I know the built bottom end won't improve power, and the low compression is actually hurting power. It was my understanding that low compression can and should run more timing advance. I do plan on a dyno tune sometime this summer, but I have a few more changes to make before paying for a tune. I'm just wondering if I'm excessively retarded under 100 kpa or if the lower C/R doesn't make that big of a difference.

I will get a new log soon. I had a few saved on my dedicated tuning laptop, but my daughter killed the laptop with a chocolate milk incident.
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Old 03-12-2019, 06:44 AM
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The half point in lower compression isn't making any less power than the engine made at the factory. It just doesn't make that much of a difference.

As said above, post a catalog of a 4th gear run from 1k rpm, WOT, to whatever speed you are comfortable with. Let's see how the turbo is responding.


EDIT: I went a read one of the links above, about using a t3 on a 1.6. It was basically 3 pages of people saying it does, and always will.suck on a 1.6. So.....I guess your car is proof of this? Not being a jerk. Just reading the words.
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Old 03-12-2019, 12:04 PM
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Originally Posted by ryansmoneypit View Post
EDIT: I went a read one of the links above, about using a t3 on a 1.6. It was basically 3 pages of people saying it does, and always will.suck on a 1.6. So.....I guess your car is proof of this? Not being a jerk. Just reading the words.
No offense taken. I know the T3 probably isnít optimal. I will eventually build a 1.8, so Iím not looking to buy more parts for the 1.6. Looking over some of the data it looks like some are getting 12psi at 3500 rpm on a 1.6. I will try my best to get a log tomorrow, but I know mine isnít spooling that fast.
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Old 03-12-2019, 12:37 PM
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You can go up to around 40 degrees in the high vacuum cruise cells to improve fuel economy.
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Old 03-13-2019, 09:26 PM
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I attached a datalog and my current tune. I did a 4th gear pull at the 18 second mark, there was some hesitation and it didn't feel that strong. I also did a few quick 3rd gear hits after the 4th gear pull. It does look like I'm hitting 12psi by 3500rpm.

Feel free to insult my intelligence and tell me how awful my tune is. That's how I'll learn.
Attached Files
File Type: msq
2019-03-13_21.05.04.msq (116.8 KB, 7 views)
File Type: msl
2019-03-13_18.48.08.msl (717.1 KB, 5 views)
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Old 03-16-2019, 08:04 PM
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Old 03-16-2019, 09:35 PM
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At the risk of sounding callous... get a different turbo.
There's way too much information already here about the performance of your turbo... and none of it sounds promising.

Nice jpeg though. Poscat for that.
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