Taza's Blowing Black Smoke

By having the 2.5 instead of doing the turbo conversion sounds like a smart move taza :)

I think you are doing the right thing by going down this avenue :iconwink:

Regards
Mr Turbo
 
Ratbag said:
...All this translates into being more careful of your accelerator foot when in LR first and second with the 2.5L, otherwise you might break something ...
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I think you don't give subaru enough credit about how strong their gearboxes really are. Abused by a driver that doesn't know how to drive properly, well, any gearbox will let go, and if it's not the box it'll be the diff.

The stories of blown gearboxes are usually from anyone that's got a high powered turbo engine without doing anything with the gearbox or those that are rough with gear changes constantly.

If you work on good driving technique and skills (which I don't think 90% of drivers understand what this means) then you'll be fine. Your gearbox is not going to blow up on you while daily driving or enjoying some offroading if you're sensible.

Ratbag said:
I reckon that I would break something serious in mine if I were to pop the clutch at (say) 4000 rpm on a hard/resistant surface in LR first. This will go double for you with your lower gearing.
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If you're stupid enough to try this, you deserve to have your gearbox let go!

Sorry to "get on my high horse" but rash statements like this just get under my skin! It's not aimed at you Ratbag, just one of those general myths getting around that are nothing but wrong.

Cheers

Bennie
 
Ratbag said:
All this translates into being more careful of your accelerator foot when in LR first and second with the 2.5L, otherwise you might break something ...

El_Freddo said:
I think you don't give subaru enough credit about how strong their gearboxes really are. Abused by a driver that doesn't know how to drive properly, well, any gearbox will let go, and if it's not the box it'll be the diff.
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I give them plenty of credit for building a flaming good vehicle in every respect. However, once one starts modifying any vehicle, all bets are off, and one needs to take cognisance of the impact of such modifications ...


The stories of blown gearboxes are usually from anyone that's got a high powered turbo engine without doing anything with the gearbox or those that are rough with gear changes constantly.

If you work on good driving technique and skills (which I don't think 90% of drivers understand what this means) then you'll be fine. Your gearbox is not going to blow up on you while daily driving or enjoying some offroading if you're sensible.

I reckon that I would break something serious in mine if I were to pop the clutch at (say) 4000 rpm on a hard/resistant surface in LR first. This will go double for you with your lower gearing.
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If you're stupid enough to try this, you deserve to have your gearbox let go!

Sorry to "get on my high horse" but rash statements like this just get under my skin! It's not aimed at you Ratbag, just one of those general myths getting around that are nothing but wrong.
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I am certainly not stupid enough to try this, but I am not talking about myself. I am trying to communicate to Taza the possible ramifications of a vehicle modified in the way he proposes. Higher torque combined with far lower gearing has its potential hazards ...

I have owned a few highly modified vehicles in my life. I understand from personal expensive, experience what those ramifications are.

Taza has spent a small fortune modifying his car. I would not like to see this sensible modification go pear shaped. I do not think that there is anything wrong or misguided with my concern for one far younger and less experienced than myself. Quite the contrary.
 
Ratbag said:
I do not think that there is anything wrong or misguided with my concern for one far younger and less experienced than myself. Quite the contrary.
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I totally agree. As I said this wasn't aimed at you ;)

Cheers

Bennie
 
I've learnt my lesson with the gearbox guys... I know they aren't designed to handle dropping the clutch from 4000rpm. I don't plan to, with the extra torque of the EJ25 I think with my gearing and larger tyres it should match pretty well. Should be similar to that of stock SG (except for the low range).

Ratbag, there are 2 H6's driving around with even weaker low range gear sets and they are given hell (not abused) and hold up fine so I don't think I will have a problem.

As I said earlier I want it to be a offroad/touring car that can take you to the beach for a surf or up a hill to see a view. Just have fun, not a sports car (thus no turbo) and with what it will have I think that will be adequate. I am very aware they are not proper 4WD's and don't want to go super hardcore, just light to minor stuff while being a good daily driver which I think my car will fit my needs perfectly when complete...

Thanks Mr T and Thunder

EDIT: Ratbag, I am not going to be dropping the clutch from 4000rpm!
My gearing should be fine as I am running larger tyres with the extra power and lower gearing it should suit well.
The reason for the 2.5l over rebuilting the 2.0l completely is that it means I won't have to thrash the car to get it from point A to point B. For example up a sand dune that Stilson can go up I have to be at redline screaming it up while he could do the same at almost half the revs. On the lhighway with a load I have to rev the ring out of it in 4th gear every time I want to overtake. The 5th gear pull from Davidov's EJ25 Outback out pulls my 4th gear, thus meaning I am not causing as my wear and tear.
The the 2.5l I am still keeping good fuel economy too for daily driving yet having enough power for 99.9% of situations.
To maintain my momentum or speed offroad up a hill or through soft sand I can do it at 2500rpm rather than 4000-4500rpm and use highrange more as I won't be struggling as much. (Tested my car vs a few EJ25's on and offroad).

I am not having a go at you guy's but I think it is a good all round motor that will suit my needs. Now after running the smaller tyres(stock) for a few days it has made a considerable difference to my gearing and engine performance. Especially noticeable when trying to pull onto the freeway. I can pull for 60-70km/hr in 5th upto 100km/hr easily without even being flat on the throttle, while with my larger tyres I will be in 3rd until 100km/hr and even then it's struggling to get upto speed.
The motor has to work too hard... thus causing more engine wear, especially if you have to do this everytime the car is driven, over 100,000km..
 
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It will be interesting to see how your petrol consumption is (with these wheels & tyres) compared to before too taza :iconwink:

I'm sure it will be better aswell :)

Regards
Mr Turbo
 
Gidday Taza

taza said:
I've learnt my lesson with the gearbox guys... I know they aren't designed to handle dropping the clutch from 4000rpm. I don't plan to, with the extra torque of the EJ25 I think with my gearing and larger tyres it should match pretty well. Should be similar to that of stock SG (except for the low range).
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Yup. But you also need to think in terms of torque acting in both directions. We all think of torque as being applied by the engine/gear train to the wheels, but there is an equal and opposite torque applied at the gearbox/engine end. When you get your head around this, it makes it far easier not to mistreat one's wagon - just IMHO, of course :iconwink: :cool:.


To maintain my momentum or speed offroad up a hill or through soft sand I can do it at 2500rpm rather than 4000-4500rpm and use highrange more as I won't be struggling as much. (Tested my car vs a few EJ25's on and offroad).
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You will definitely find that to be the case. I had to rev the ring/s off Roo1 to get it to go anywhere. Mind, it was a ready revver from about 3500 rpm and up, and was like it had a full race, high lift, long duration camshaft from about four grand up to the limiting point at about 6500-6600 rpm. There is really no substitute for low down grunt and a flat torque curve, IMO.

I am not having a go at you guy's but I think it is a good all round motor that will suit my needs. Now after running the smaller tyres(stock) for a few days it has made a considerable difference to my gearing and engine performance. Especially noticeable when trying to pull onto the freeway. I can pull for 60-70km/hr in 5th upto 100km/hr easily without even being flat on the throttle, while with my larger tyres I will be in 3rd until 100km/hr and even then it's struggling to get upto speed.
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The 2.5L N/A donk sure is a willing worker! Not quite in the same league as the pulling power of a 4.2L Jag engine, but certainly very pleasant and tractable to drive. Only time I rev Roo2's rings off is when someone is giving me a PITA ... :lildevil:

The motor has to work too hard... thus causing more engine wear, especially if you have to do this everytime the car is driven, over 100,000km..
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I quite agree, mate. Subaru do not make bantam weight cars - they are pretty solid, and relatively heavy. The bit bigger donk with a lot more torque makes them far nicer/better to drive wherever.
 
taza said:
Now after running the smaller tyres(stock) for a few days it has made a considerable difference to my gearing and engine performance. Especially noticeable when trying to pull onto the freeway. I can pull for 60-70km/hr in 5th upto 100km/hr easily without even being flat on the throttle, while with my larger tyres I will be in 3rd until 100km/hr and even then it's struggling to get upto speed.
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As ratbag has said, running the EJ25 will help with drivability with the larger tyres. The other thing with the above comment is that the stock tyres you've borrowed (the alloys I believe) will be significantly less weight than your oversized tyres and steelies.

This means that while you're increasing the rolling diameter you're also increasing your energy requirements to spin those babies quicker and also making it harder to slow them down...

Thought I'd add that for you - could be a great idea to look for a set of light weight rims.

Cheers

Bennie
 
I'm glad to hear you're going EJ25. The turbo is a hoot but an expensive option for you. I think this makes much more sense & gives you a great offroad Foz. Do you know what is needed for the wiring loom? Do you need a custom splice?
 
Nope NL, no custom splice or wiring as I'm using my current stuff.

Sourced a block today. $450 with damaged heads due to being in an accident. From a 2004 Impreza RX 2.5l. Only has 131,000km on it. I can use the heads off my old EJ20 as they had only done 165,000km and just get a minor service and skimming done on them. Bolt them on, with new head gaskets and oil rings and it will be almost like new.
Then lastly drop it in over a weekend and get the tuning card installed. I should then be producing EJ25 power :lildevil:
 
taza said:
...a 2004 Impreza RX 2.5l. Only has 131,000km on it. I can use the heads off my old EJ20 as they had only done 165,000km and just get a minor service and skimming done on them. Bolt them on, with new head gaskets and oil rings and it will be almost like new.
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And a FRANKEINMOTOR as the USMB crew call them! Should be an interesting combination. I'd highly recommend running ONLY 98RON with a setup like this. It'll have high compression and go like the clappers.

RSR555 (ausubi) might be able to elaborate further, but I think you'd use the headgasket that matches the head - so a stock foz unit.

I'm excited for you Taza, can't wait to see how this goes!

Cheers

Bennie
 
El_Freddo, Paul (RSR) recommended this setup to me. I have spoken with him previously about it and this evening he explained in much better detail (in person) while moving over his workshop/s.
He said the heads from the EJ20 and EJ25 in both SOHC are almost identical bar from some minor differences and said with a tuning card I shouldn't(not definitely) have to run RON98.
Anyway I'm keen to see how it will go, even if I do have to run Premium fuel all the time for the extra power it should be worth it :D

Oh and thanks ;)
 
Yeah I should have known that you've been talking to him!

Bummer mate (on my end) - I was hoping I'd see a frankenmotor some day, I thought you could be the one. But they do use the EJ22 heads which being a different generation of head development would be different, hence the higher compression.

I'm looking forward to seeing the result and what you think of it.

Cheers

Bennie
 
Looks & sounds like you have it all thought out taza :)
Looking forward to seeing it up & running too mate :raz:

Once you've had it fitted are you going to put it on a dino to see what it produces ? It would be interesting to see what it's numbers are :iconwink: :ebiggrin:

Regards
Mr Turbo
 
mr turbo said:
Once you've had it fitted are you going to put it on a dino to see what it produces ? It would be interesting to see what it's numbers are :iconwink: :ebiggrin:
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Thanks Mr T. Yes I'm interested myself. After much research and discussion it should be very similar to that of a standard EJ25. Since I will have to tune it(add more fuel as I'm using the stock 2.0l computer) and will be adding an exhaust plus my lightweight pulley I should be producing a decent amount of power at the wheels and considerably more than a stock 2.5l Foz... I hope it all goes well :cool:
If I'm getting around 130Kw (at the crank) and 240-250Nm of torque I will be very happy. Those numbers should be achievable too :D
 
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