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Scott in Bellingham

I am looking for more power down low below 1000 RPM

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got my Wheeler going, its runnin a stock EJ22 stock everything, noticed then when wheelin most the slow going is like 100 rpms, is there anyway to get more power down in them low RPMs?

maybe somethin  with the electronics?  I know I can install the Delta cams which ive done on past wheelers , if electrons  make a difference would be cool to have a switch on the dash to make the change, any thoughts? 

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Unlikely because all subaru boxer engines don't have much mass/inertia  below 1500/2000rpm (flywheel etc ) for low down torque because cylinders oppositely opposed they are well balanced no need for it.  An alternative is to go to a lower diff ratos if you want to go slower over the rough stuff. (and assuming you already have dual/ratio as well)

If you want that sort of idling torque, need to consider a diesel alternative.

Edited by subnz

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Unlikely because all subaru boxer engines don't have much mass/inertia below 1500/2000rpm (flywheel etc ) for low down torque because cylinders oppositely opposed they are well balanced no need for it. An alternative is to go to a lower diff ratos if you want to go slower over the rough stuff. (and assuming you already have dual/ratio as well)

The mass of an unlightened flywheel mixed with Delta torque cams makes a lugger. I have had it in front of an automatic, and a 5 spd. Both combinations have given more "power" down low.

There is plenty of low RPM usage from these vehicles. We all have been doing it for years.

 

Just because the engine is balanced does not mean it can not "lug" .It actually helps it lug really. lol

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The only electronic thing I could think of is to advance the timing at low RPM. Could probably advance it a fair amount, especially on high octane.

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Don't forget, it needs to breathe freely, restrictive intakes are death to torque, but by the same token, too open and they won't develop proper cyclic flow and will impede torque development as well.

 

-OR-

 

propane injection...

solenoid valves, flex tubing to the intake, flip a switch, power up and go.

 

(its popular here in the Montanas)

truthfully I do not know if that even works, to my thinking, it is counterproductive at low RPMs but I know a couple of guys out here who swear by it. (never ridden with them, so I cannot say for certain)

 

and yes, this on on normally aspirated gasoline fueled engines.

Although...I hear is a hoot in a diesel!

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got my Wheeler going, its runnin a stock EJ22 stock everything, noticed then when wheelin most the slow going is like 100 rpms, is there anyway to get more power down in them low RPMs?

maybe somethin  with the electronics?  I know I can install the Delta cams which ive done on past wheelers , if electrons  make a difference would be cool to have a switch on the dash to make the change, any thoughts? 

 

By electronics do you mean some kind of controller or do you mean an electric motor(s)?

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The only electronic thing I could think of is to advance the timing at low RPM. Could probably advance it a fair amount, especially on high octane.

 

 

how would I go about doing that?  seems like you would want to retard the spark for low RPMS like on my Model T

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The flywheel off a 2.5l in a 97-99 legacy Outback is a lot heavier than the same year 2.2l one, so that would help with keeping it from stalling out. A 2.5L shortblock would help more...

 

Superchargers won't help much at 1k rpm unless you have the supercharger's ratio set way faster than the crank and you won't be able to run the engine over 3k without the supercharger exploding at that point.

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You can get some benefit by shifting the cam timing, even more so if it is a DOHC.  The current cam timing is optimized for somewhere around 3k-4k.  Adjust the cams so that the intake valve closes as close to BDC as practical, and if DOHC adjsut the phasing so that there is minimal valve overlap.

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All this ie  changing cam timing,  forcing induction, retarding ignition, isn't worth the expense for the small gains? if any? The motors turning over too slowly for any of these things to make that much of a difference.

 

The design/characteristics of these motors (modern engines) is wrong to modify for torque at idling. engine too short stroking  ie square to over square, [bore = stroke to, bore greater than stroke]. this short stroke design is best for high rpm.

 

Need undersquare engines ie stroke greater than bore ie similar to old school ohv 6 cylinder ford/gm engines pre V8s over 50 years ago. for high torque values at low rpm but not good for rpms ( vibration - self destruction)

 

 Diesels are better because the are under square (stroking engines) also have about twice the compression (compression ignition) of gasoline engines so have stronger power impulses at idle (more torque) are more simple and don't need to be modified the same

Edited by subnz

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All this ie  changing cam timing,  forcing induction, retarding ignition, isn't worth the expense for the small gains? if any? The motors turning over too slowly for any of these things to make that much of a difference.

 

The design/characteristics of these motors (modern engines) is wrong to modify for torque at idling. engine too short stroking  ie square to over square, [bore = stroke to, bore greater than stroke]. this short stroke design is best for high rpm.

 

Need undersquare engines ie stroke greater than bore ie similar to old school ohv 6 cylinder ford/gm engines pre V8s over 50 years ago. for high torque values at low rpm but not good for rpms ( vibration - self destruction)

 

 Diesels are better because the are under square (stroking engines) also have about twice the compression (compression ignition) of gasoline engines so have stronger power impulses at idle (more torque) are more simple and don't need to be modified the same

I understands its not  THE  best choice for low RPM Tork  but its what Im going to stick with,  and yes if theres any gain in lowend power  then it is worth the effort , if  I cam make a few simple adjustments or additions to accomplish this  then Im all for it,

 

 

You can get some benefit by shifting the cam timing, even more so if it is a DOHC.  The current cam timing is optimized for somewhere around 3k-4k.  Adjust the cams so that the intake valve closes as close to BDC as practical, and if DOHC adjsut the phasing so that there is minimal valve overlap.

 

ok Its a bone stock SOHC the one that came in the car  its a 90 EJ22 , so how would I do this? , move a tooth on the belt? or somekind off slotted adjustable cam?

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boo on the delta cams put in a set in 2.2 and lost alot of bottom end good 3000and up but 1000-3000 dog was very dissapointed with them. Give it a sniff of NOS like a 15 hp shot jsut to get it outa the hole or mabee find a way to slightly addvance timing

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EA81 it scott!!!!

 

Jeff

 

He said he wants more power. lol

 

Ohh.....I get it you think since it's so tiny the weight loss will give him more power?

 

I just leave my Girlfrieind home if I want to drop 110Lbs.

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ok Its a bone stock SOHC the one that came in the car  its a 90 EJ22 , so how would I do this? , move a tooth on the belt? or somekind off slotted adjustable cam?

Basically, any engine can be made to have its torque peak anywhere in its rpm range (limited by VE at the upper RPMs).  To lower the torque peak, you need to do the opposite of what most tuners do for more horsepower:  Less radical cam timing, smaller intake tracts, smaller valves, less carburetion.  And more rotating mass (heavy flywheel) to make better use of the less frequent power pulses.  With work, you can make the EJ22 reach full torque at 100RPM... but it will suck by 1000RPM.

 

If I were to do adjustable timing on the SOHC EJ, I would probably mount an extra idler wheel on the tension side of both T-belt runs, and make these idlers adjustable (like the fine adjusters on A/C tensioners).  You could then use these to "dial-in" each cam's timing.  The actual adjusting would have to be slow to allow for the tensioner to compress, and which one you do first is likely to be important (due to shared belt and tensioner), but my migraine is preventing me from thinking this through.

 

Edit: IF you make the cam changes and use a narrowed intake runner, THEN...  (endedit)

You might also get some changes (hopefully good ones) by deactivating one intake valve of each pair. 

 

All of this will lower max HP and max usable RPM.

Edited by NorthWet

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boo on the delta cams put in a set in 2.2 and lost alot of bottom end good 3000and up but 1000-3000 dog was very dissapointed with them. Give it a sniff of NOS like a 15 hp shot jsut to get it outa the hole or mabee find a way to slightly addvance timing

 

NOS, now that's interesting, don't know anything about that,

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In the spirit of old bus/med duty truck engines. Would running an ej18 intake and heads with a 2.5 short block with heavy flywheel produce lots of low end torque via long stroke and small valves?

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