Jump to content
LegacyGT.com

my Subaru will beat with a Buick heart!


Recommended Posts

ok so set it to 30 and see what mpg's you get !

 

Couldn't possibly burn a piston by advancing timing too much?

it was bad as shit on gas for a while. i kept advancing the ignition timming and it kept getting worse and worse. i went up to 46 deg advance now i'm running 23-25 and wow what a difference. i wonder what the subie motors would do if you retarded the timming a shit load to 23-25 deg in cruse areas

 

If I felt confident enough in technical knowledge I would try it. But when it comes to tuning I would rather live that to those that know much more than I.

Link to comment
Share on other sites

  • Replies 1.5k
  • Created
  • Last Reply

Top Posters In This Topic

It's retarding timming actually. And it actually cools the combustion temps down but hotter exhaust gas temps. I'm not sure why retarding helped it could be because it's such low compression ratio and it would almost never knock. A Honda or similar engine would run 25-30 deg timming.

Now that's thinking out of the boxer!:lol:

fyi all 05 + legacy's have built in code reader

Link to comment
Share on other sites

It's retarding timming actually. And it actually cools the combustion temps down but hotter exhaust gas temps. I'm not sure why retarding helped it could be because it's such low compression ratio and it would almost never knock. A Honda or similar engine would run 25-30 deg timming.

 

Oh, I see. I guess I had that backwards. I wasn't thinking about the flame still being ignited in a "retarded" situation. Whereas, I'm assuming, in an advanced situation you are concentrating more heat inside the combustion chamber thereby possibly causing a piston melt situation. Correct? Thanks frank.

Link to comment
Share on other sites

Oh, I see. I guess I had that backwards. I wasn't thinking about the flame still being ignited in a "retarded" situation. Whereas, I'm assuming, in an advanced situation you are concentrating more heat inside the combustion chamber thereby possibly causing a piston melt situation. Correct? Thanks frank.

 

well ignition is always fired before top dead center.

 

technically speaking we should say more advanced and less advanced since its always in advance of piston top dead center.

 

chamber temperature come from a number of varibles.

1 as we have already mentioned is timming advance the more the timming is advanced the more time the flame is actually in the chamber. if you retard timming the flame is shorter time in the chamber. but then the rest is lost out of the exhaust. so in that theory you want to run as much timming advance as possible. the limitation is knock where the piston and spark plug and other parts become very hot. the parts get very hot it can cause preignition or "knock" where you may have fire at 60 deg BTDC or more. and the type of flame can become an explosion. there the diffrence can be expressed as lighting a bbq vs a stick of dynamite. so when knock its like there is a stick of dynamight in a bbq. where it may just blow the top open. or blow everything to bits !

 

2 fuel ! well there are a number of things happening with fuel and what i have learend with playing with injection timming. if you inject fuel as the last possible moment before the intake valve closes ~180 deg btdc the engine will tend to knock more! since the fuel is spending less time cooling down the piston and getting mixed up ( this is what i believe maybe there is more to it )

running rich will cool the chamber and piston and to balance that you would need to advance timming

running lean the chamber tends to get hot and need to run less advance.

 

for the most part we know that we should run at stoichiometric ( ideal chemical burn ) to have a clean burn. most new cars run stoichiometric all the time. turbo cars for the most part cannot because there is to much chamber heat.

when running richer than stoichiometric there is a area of increased power. at the 12-1 afr (for gas )

 

but anyways for the fuel effency game when you run a lot of timming to achieve hot chamber on the verge of knock the fuel is burned cleanly.

but in the case of low compression 9.5-1 on your subarus and 7.5-1 on my buick engine. that point ends up being in the 45 deg btdc area. but if you can imagine riding a bike and you press down on the pedal before it reaches the top ! this is called negitive work. civics and other types high reving engins run 23-25 deg in the cruse range and 10-15 deg at high rpms.

 

but if you guys hear what i talk about on low compression cars its better to run low octane fuels because the knock point will be at 38-35 deg instead of 46-48 deg in cruse. the result is less negative work with lower octane fuels.

 

for some one with a lgt if they retarted the whole map by 10 deg and ran 87 octane i would think that 35+ mpg would be achieveable. why does subaru not do this ? well for emissions. but the new models are probably do this in other ways, with altered head designes and chambers, higher compressions etc. would the car be much more dirty ? i'm not sure. the exhaust gas may be hotter so the cats would work better, and the car would use less overall fuel.

Now that's thinking out of the boxer!:lol:

fyi all 05 + legacy's have built in code reader

Link to comment
Share on other sites

just pulled off the oil pan ( the supid silicond gasket split )

i checked all the bearings and they look like the day i put them in !

so gonna silicone the pan gasket and shove it back on after retorqueing the bearings bolts.

Now that's thinking out of the boxer!:lol:

fyi all 05 + legacy's have built in code reader

Link to comment
Share on other sites

How did the oil pan gasket work out, did you fix the leak ?

 

You did reuse the old gasket ?

 

the gaskets for the oil pan are super soft silicone. when you torque the bolts enough so they dont fall out after a day it splits the gasket! i wish i could ge an original cork one!. but i just used silicone and no gasket.

 

but some thing else is leaking mybe the rope rear main seal. i should change it to the two peice lip seal. that i got once with a kit.

Now that's thinking out of the boxer!:lol:

fyi all 05 + legacy's have built in code reader

Link to comment
Share on other sites

just figured out the crank sensor to get the stock tac woking proporly.

look at how fast it shifts!

it seems to be reving past its peak. i have valve spings in the truck i'll try and install monday night.

[ame=http://www.youtube.com/watch?v=XJ-IXqfXJHo]buckaru still 5 lbs boost hex mods valve body mod - YouTube[/ame]

Edited by frank_ster

Now that's thinking out of the boxer!:lol:

fyi all 05 + legacy's have built in code reader

Link to comment
Share on other sites

it wasn't even the pan or the rear main seal it was the -12 fitting on the oil drain that came loose !

Now that's thinking out of the boxer!:lol:

fyi all 05 + legacy's have built in code reader

Link to comment
Share on other sites

just figured out the crank sensor to get the stock tac woking proporly.

look at how fast it shifts!

it seems to be reving past its peak. i have valve spings in the truck i'll try and install monday night.

 

I did a wtf double take the first time I watched this video this morning.

Then I noticed the top numbers on your speedometer are kilometers. :lol:

Link to comment
Share on other sites

still did another 60 milles before filling it !

 

also the car is amazing with my fancy waste gate open switch. where it uses vaccum from the booster to hold the wastegate open.

 

results in less back pressure and makes the engine a LOT more responsive where city driving feels like i'm driving a 350 camaro with 4.10 gears. it just throws me back in the seat even at half throttle and jumps up to 35 mph in no time what so ever.

Now that's thinking out of the boxer!:lol:

fyi all 05 + legacy's have built in code reader

Link to comment
Share on other sites

I did a wtf double take the first time I watched this video this morning.

Then I noticed the top numbers on your speedometer are kilometers. :lol:

 

I remember driving to Canada when I was really young and getting excited because I thought their 100 km/h speed limit signs were 100 MPH.

Link to comment
Share on other sites

  • 2 weeks later...
just driving it.. realy want to connect up my a/c the compressor is there and belt turning its pulley. so i just need to put a condencer in and connect the hoses. problem is the stock condencer doesn't fit inbetween the head lights. so i got a universal one from summit racing. and i need to make a few custom fittings.

Now that's thinking out of the boxer!:lol:

fyi all 05 + legacy's have built in code reader

Link to comment
Share on other sites

noticed some dampness around the weep hole of the water pump.

changed it out today at my girlfiends house with crappy tools took 15 min and was 33$

Now that's thinking out of the boxer!:lol:

fyi all 05 + legacy's have built in code reader

Link to comment
Share on other sites

just driving it.. realy want to connect up my a/c the compressor is there and belt turning its pulley. so i just need to put a condencer in and connect the hoses. problem is the stock condencer doesn't fit inbetween the head lights. so i got a universal one from summit racing. and i need to make a few custom fittings.

 

Custom fittings...where in the world are you going to find them...(joking)

 

noticed some dampness around the weep hole of the water pump.

changed it out today at my girlfiends house with crappy tools took 15 min and was 33$

 

Water pump replaced in 15 min, yea right, that must of been on canadian time... LOL

305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD).  CHECK your oil, these cars use it.

 

Engine Build - Click Here

Link to comment
Share on other sites

Custom fittings...where in the world are you going to find them...(joking)

 

 

 

Water pump replaced in 15 min, yea right, that must of been on canadian time... LOL

 

6 bolts an nothing to remove but the belt :lol:

Now that's thinking out of the boxer!:lol:

fyi all 05 + legacy's have built in code reader

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



×
×
  • Create New...

Important Information

Terms of Use