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I am looking for more power down low below 1000 RPM


Scott in Bellingham
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EJ engines seem to have very little torque on idle  in my experience  eg need 1200/1500rpm to pull away in 1st gear on the flat without slipping the clutch to avoid stalling on EJ 251  SOHC on my (2nd Gen Outback) and the EJ 251 SOHC is noted to have better mid range torque values than DOHC  ( SOHC has a flatter torque curve)  (most of torque happening by 3000rpm -  pulling stongly @ 2500rpm even though max torque quoted at 4000rpm)

The head design / valve configuration is different between DOHC / SOHC engines.    DOHC engine better for top end than SOHC,  SOHC better mid range than DOHC,  even though actual power/torque quoted for both is not that much of a difference  .

 

EJ engine max torque values range from 2800 to 4500rpm.

 

 

Probably the best EJ engine to use is the notorious (internal head gasket failure)  earlier versions of EJ25D coz max torque @ 2800rpm

 

EA82 SOHC (1800) which I have had 2 of was similar to EJ251 pulling away too (max torque @ 3200rpm) in which EJ engines were based on.

 

Probably the best engine to use is the EA 81 (ohv 1800) ex Brat /  2nd gen Leone

l have one (87 Brat) and its much stronger on idle (torque) than all the previous I've mentioned  ie (max torque at 2500rpm) 

 

http://en.wikipedia.org/wiki/Subaru_EJ_engine

 

http://en.wikipedia.org/wiki/Subaru_EA_engine

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The stock turbo 2.2 cams kill the delta cams 10 to one. Anyway have heard about a offset pin to hold cam gears to alow for addvance of cam gear might help. I also like the above idea of 1.8 heads valves are same size but ports are smaller this may help bottom end. Also converting to 98 and up roller valve train may help bottom end. Or like I said a small sniff of Nos hooked to wot switch a dry 15-20 shot will kick it in the pants but not break anything and it can be timed out

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The problem with the nos is he needs it more or less continuously for trail riding.

 

realistically his best option is a divorced transfer case so his ground speed can be the same or slower and his engine can be in a spot that makes power.Even idling along in 1st gear lo/lo his torque is doubled.

Edited by Uberoo
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Who idles there subaru along ? my offroad outback sport dosent even touch the ground full out all the time. Never runs outa power but never drops under 4500 rpms. A extra trans case is alot of extra weight and fabracating. I a'm all about geting the offroad car as light as posibble. Want more power lighten it up

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Who idles there subaru along ? my offroad outback sport dosent even touch the ground full out all the time. Never runs outa power but never drops under 4500 rpms. A extra trans case is alot of extra weight and fabracating. I a'm all about geting the offroad car as light as posibble. Want more power lighten it up

 

Your not doing the type of trails we are then. 

 

2~3' diameter rocks in the trail, 40 degree inclines, twistys around tree roots.

 

4500 rpms in my wheeler in 1st lo would be 12~15 mph......too fast for trails.

 

That's why they call it "crawling"

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Who idles there subaru along ? my offroad outback sport dosent even touch the ground full out all the time. Never runs outa power but never drops under 4500 rpms. A extra trans case is alot of extra weight and fabracating. I a'm all about geting the offroad car as light as posibble. Want more power lighten it up

Look at some of the pics in scotts build thread of this car,specially page 3 and 4 to get an idea of kind of terrain he is dealing with.You can't go 12-15MPH over that stuff at least without serious breakage.A big truck with super soft and flexy suspension and big tires airs down possibly,a subaru with mostly stock suspension-not possible.

Edited by Uberoo
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Well lets see rocks roots hills why slow down i get your point if you want it to do that you need a 4eat with high stall the race buggy can idle along at the point were tires are just barly moving as slow as you want tons of power in reserve and hills no problem as touque converter holds car at whatever rpms you want. On a rock crawler i whould only use auto. On trail bashing offroad car 5 speed DR all the way. You just cant beat a auto when it comes to going slow

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High stalls came in 89-92 legacy and 90-97 imprezas is 2800 stall outback 95-00 is 2100 stall i sent out a 90 legacy torque and had it redone they got it up to 3800 stall I was hoping for 4000-4500 but 3800 was a big inprovment useing the 4.44 gears from a 98 outback with case and ceter from 90 legacy with direct line preshure to awd pack 0 valveing or soilinionds. This trany has had 5 years of hard raceing / offroading on it and no problems. Other than some fillter ishues coating came off the pan ended up in fillter.

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with 2100 stall engine is not in power band / torque curve at 3000 or better getting closer meaning you can hold engine at 3000 rpms while tires barly move. For me i use it to get engine boosted before launch so when i whack it with 120 shot of nos the engine has enuff rpms/boost to eat it and not stall or break.

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A decent cooler, and synthetic fluid should keep things operational.

I've seen the radiator out of the 1200 Honda Goldwing with a small electric (thermostatic controlled) fan used very successfully in several rigs out in the Arizona Deserts.

The automatics were used because there was some rock crawling involved as well as some wide open across the valley floor blasts, for all around offroading I have to agree, an automatic really helps things along.

(an automatic with a skid plate, gotta protect the bottom of that case at all costs)

 

I used to take my 6800# fullsize Bronco with 5.0 and the (stupid) AOD4 offroading all the time, the neat thing about autos is that you can point the thing downhill, and throw it in reverse, locked in 4x2 low (4x4 selected with the hubs unlocked) you just crawl down with the throttle used as the brake, add throttle to slow your descent, if you touch too much throttle then only the rear wheels spin, you can still steer, then use brakes if you need to. handy.

Yeah, I know there are purists who claim you cannot do that without damaging the tranny, and yes, if you are screaming downhill (or even just on the flat) at any rate of speed and throw it into reverse, bad things can (and should) happen. (remember, physics is the devils volleyball...)

I've been doing it that way ever since...well ever since I've been driving and have yet to tear up a tranny.

(TH400s are bullet-resistant, TF727s are flat out indestructible)

Point downhill, come to full stop, engage reverse, ease down with the transmission and engine dragging torque. Of course its a REAL SLOW descent, like walking/crawling speed, but its fully controlled and one does not have to deal with braking. With a good (read that as aftermarket) trans cooler its an effective means of traversing God's green (and brown and red and purple) earth.

 

Sounds like you are on the right track with the auto.

Keep us posted, (please)

 

adventurously

timothy

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Maybe you'll find my question Foolish, but still I'll let it Go:

 

If you really want Torque at Low RPM's, very kindly, let me ask if you already considered the option of converting your Vehicle, to Electric Motor(s)?

 

You Know: Instant full Torque, despite the Motor's RPM's. There shouldn't exist anything better for that purpose.

 

Maybe you could find not too expensive electric conversion designs online; I saw once an 1980's Jeep wagon converted to twin electric motors and a Battery Pack in the Rear... and you can use a small power plant to recharge / keep power anywhere...

 

Kind Regards.

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Some background info:

 

~► http://www.wikihow.com/Build-an-Electric-Car

 

~► http://www.ev-america.com

 

 

If you want an Adapter plate + mounting hardware to couple the Subaru transmission to an Electric Motor, you can obtain it, here:

 

~► http://www.electriccarinternational.com/Adapter-Plates-and-Mounting-Hardware.php

 

Kind Regards.

Edited by Loyale 2.7 Turbo
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not really reliable for serious offroading, dust, water crossings, caked mud. all enemies of the electric drive.

Of course, of you can seal it up AND still maintain the cooling required for the motor (they generate acres of heat) then you'd be in business.

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And yet the most common failure I see offroad with traditonal 4x4's is the automatic hating life.

Yes, and I am willing to bet that those were poorly operated, insufficiently cooled, and rarely maintained units.

I can kill an automatic on flat pavement if its been abused and operated beyond its capabilities.

 

So unfortunately, yes, for ultimate reliability in a trail vehicle a nice four speed (who in the heck needs a fifth gear on the trails?) will stand the test of time, but for us real part-timers an automatic can be your best friend (or if abused, or poorly maintained, your worst nightmare).

 

still, there's nothing like an old M151-A1 fully articulated with a set of coopers crawling in first over everyfreakingthing in sight.

ahhh...simplicity...

 

Build it, run it, rock on!

laughingly,

timothy

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