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So I'm trying to decide what to do with my other block. I'm going to need a block for my sedan now since I so graciously donated it's block to my wagon so I could get that back on the road. :rolleyes:

So the question I'm faced with is: Find a 2.5 block and build a frankenmotor,

Or rebuild the wagon block and build it for slightly higher compression?

I'm trying to look at this from a cost perspective.

Either way the block I choose to use will get rebuilt. I might be able to get away with reusing the bearings in the 2.2 block, but I'll have to tear it down and see how they look. I just don't trust the 2.5's enough to run a junkyard block outright.

 

I'm trying to figure the best way to get the extra compression from the 2.2 though, and I'm wondering what the differences were between the phase 1 and phase 2 blocks? It's my understanding the phase 2 was higher compression, (also interference, but a frankemotor would be interference as well). But where was the difference that raised the compression? Crank stroke? Piston top? Combustion chamber? Combination of all three?

Anyone know offhand?

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So I'm trying to decide what to do with my other block. I'm going to need a block for my sedan now since I so graciously donated it's block to my wagon so I could get that back on the road. :rolleyes:

So the question I'm faced with is: Find a 2.5 block and build a frankenmotor,

Or rebuild the wagon block and build it for slightly higher compression?

I'm trying to look at this from a cost perspective.

Either way the block I choose to use will get rebuilt. I might be able to get away with reusing the bearings in the 2.2 block, but I'll have to tear it down and see how they look. I just don't trust the 2.5's enough to run a junkyard block outright.

 

I'm trying to figure the best way to get the extra compression from the 2.2 though, and I'm wondering what the differences were between the phase 1 and phase 2 blocks? It's my understanding the phase 2 was higher compression, (also interference, but a frankemotor would be interference as well). But where was the difference that raised the compression? Crank stroke? Piston top? Combustion chamber? Combination of all three?

Anyone know offhand?

 

I believe Phase 2 2.2s are all single-port, so you're stuck with your stock header, which isn't the end of the world, but it matters some.

 

The consensus on NABISCO is that pistons are the best way to increase compression on a 2.2 block. With that level of disassembly, however, you're at a point where you might as well pick up a 2.5 block and benefit from greater displacement and higher compression. From a cost perspective, the 2.5 block would probably be less than the high compression pistons.

 

I hope that helped.

 

Jacob

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I'm trying to figure the best way to get the extra compression from the 2.2 though, and I'm wondering what the differences were between the phase 1 and phase 2 blocks? It's my understanding the phase 2 was higher compression, (also interference, but a frankemotor would be interference as well). But where was the difference that raised the compression? Crank stroke? Piston top? Combustion chamber? Combination of all three?

Anyone know offhand?

 

 

The major difference was a change in piston head design.

 

There was also some ecu tweaking in the timing.

 

Wasn't until 99 that they changed the piston diameter plus a few other changes.

 

O

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The major difference was a change in piston head design.

 

There was also some ecu tweaking in the timing.

 

Wasn't until 99 that they changed the piston diameter plus a few other changes.

 

O

 

So the pistons from a 97-98 2.2 are the same diameter as a 95 2.2?

 

Thanks!

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I'll look into a set of pistons for a pre-phase 2 then and see what I can find out. I don't want to be stuck running premium gas, as I hear you have to with the frankenstein. I think a small boost in compression coupled with some cams will make the difference I'm looking for and still run regular or mid grade at the worst. I'll have to get some numbers dug up so I know just how big of a difference there will be.

 

Get a 2.5 block. The compression increase is from the use of "small" combustion chamber heads.

Right but aren't the 2.5's also "peakaboo"? (The piston crown comes past the end of the block at TDC) Or was that only certain years?

I know the 2.2 piston doesn't stick up past the block.

 

I believe Phase 2 2.2s are all single-port, so you're stuck with your stock header, which isn't the end of the world, but it matters some.
The heads I have are single port anyway. And non-egr, which I would keep since other-wise I would need another intake and ECU to keep the CEL away. I'll probably need that CEL to be off because I have a feeling state emissions testing will soon come to my area.
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The 2.4 (more correctly it's a 2.35) is an EJ22 with an EJ25 crank and rods. It's stoked but not bored.

 

The cheapest power is the EJ25D with EJ22E heads. With torque cams, etc they will dyno over 190 HP. If you don't think 190 HP will be enough - try it before you knock it! In an EA chassis that's about the power-to-weight of a stock 2.0L WRX.

 

The one we built for renob123's Brat cost $700 - that's $200 for a low mileage used 25D, $165 for torque cams, $185 for a head rebuild/valve grind, ebay timing belt/idler/WP kit, and misc. gaskets, etc. You can't get that kind of power-per-dollar with any other combo.

 

GD

Edited by GeneralDisorder
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We run 92.... ALWAYS. It's a race engine and both of us are used to it from running EJ turbo's as daily's anyway. Actually the frankenmotor gets super excelent gas mileage due to it's high compression - makes the engine more effecient. Especially compared to my EJ22T that currently makes about the same HP and uses 16 MPG on premium :mad:.

 

GD

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We run 92.... ALWAYS. It's a race engine and both of us are used to it from running EJ turbo's as daily's anyway. Actually the frankenmotor gets super excelent gas mileage due to it's high compression - makes the engine more effecient. Especially compared to my EJ22T that currently makes about the same HP and uses 16 MPG on premium :mad:.

 

GD

 

Would the engine be mad about getting 87?***Or would it just retard timing and be fine?

I wanna build a franken beast. Just thinking about what if I loan the car to someone and they put crap gas in it...

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Would the engine be mad about getting 87?***Or would it just retard timing and be fine?

I wanna build a franken beast. Just thinking about what if I loan the car to someone and they put crap gas in it...

 

Some people run 87 octane on them just fine. A lot of those people are in higher elevation areas where they can get away with it. A few people at sea level do it as well, but I'm not sure if they've run into any problems.

 

Yeah I don't want to be stuck running 93. The car is gonna be lifted and probably turning 27" tires on 3.9 gearing. With my lead foot that's what will end up happening. :lol:

 

I can list a bunch of tired old sayings about the inverse relationship between money and horsepower, but I hope you already know all of them. If you're really that worried about using the fancy gas, then you really shouldn't be exploring high compression pistons or Frankenmotors or anything. I doubt raising the compression a little bit so you can still run cheap gas would be worth it or even noticeable.

 

Not trying to flame or anything. I'm just trying to put things into perspective.

 

Jacob

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the difference in price per tank between regular and premium is like $2 ? less than your cost for octane boost..

 

anytime you raise the compression in a motor you have to run higher octane fuel..

 

we build a 429/460 for my truck.. its actually like a 489 or something now, i forget.. its a 429 block, 460 crank, 429 pistons, rods, 460 high torque cam, and 429 dove heads.. and its bored .60 over

 

a stock 429 is 10-1 compression, this motor is 13 or 14-1 or so now.. if we retard the timing from the stock 6degrees to 1 or 2 degrees it will run regular gas.. but it runs like a 6cyl.. if we set the timing at 6 degrees, we have to run race fuel in it to keep it from clattering.. its pushing 500+hp...

 

the truck sits on 35's with a 6" lift, we had to put traction bars on it and huge driveshafts/ujoints.. it will roast both back tires through 1st gear into 2nd at half throttle... mustangs hate the truck, cause they always loose in a drag race against a lifted 4x4 hah..

 

point is, the more you customise/build an engine the more fine tuning it will take.. whether its gas, axles, whatever..

 

i know its not a scooby, buut.. its relavent to high compression engines..

 

i think $2 a fillup is peanuts to pay for having a high comp engine..

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I really don't want to hear ************ about the difference in cost.

Maybe where you are. Where I am it's currently $0.35 per gallon more for premium. And that keeps going up. I pay an extra ~$5.25 to fill the tank in my Lincoln just to keep it driveable, because anything less than premium makes it sound like it has rocks bouncing around in the cylinders just trying to drive up the street. I'm doing that twice a week right now. After a month, I could fill up my Subaru off that extra $40 I have to spend on premium for this car.

 

I think I got the info I wanted, so I'm going to rebuild what I have and run with it. I'm already ~$250 ahead by not having to drive to find and pay for a used engine that I have no idea what kind of condition it's in. For that I can order rings and bearings and get the block completely reworked.

I might use different pistons, I might not. I'll figure it out later.

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I can list a bunch of tired old sayings about the inverse relationship between money and horsepower, but I hope you already know all of them. If you're really that worried about using the fancy gas, then you really shouldn't be exploring high compression pistons or Frankenmotors or anything. I doubt raising the compression a little bit so you can still run cheap gas would be worth it or even noticeable.

 

Not trying to flame or anything. I'm just trying to put things into perspective.

 

Jacob

 

This.

 

If you really can't afford an extra $6 per fill up, then performance isn't up your ally man, and just use the subaru for what it is. Rebuild it with better stuff like you plan, and just roll with it. Don't worry about HP numbers or any of that jazz, just rebuild it to be reliable and be happy with it :)

 

I am going to throw out a saying I always use when it comes to this situation... You can have fast, cheap, and reliable, choose 2. You will never get all 3 of those things, and it sounds like you want cheap and reliable, so just stick with that ;)

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