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xbeerd

Frankenmotor question. Searched.

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the 2.5 twinn cam interfers in two ways the valves hitt the pistons and they HIT EACH OTHER the intake valve hitts the exhaust valve when out of time. Have built many 2.2 twinn cam engines work very good but had to use the turbo 2.2 headgasket slightly modifyed. I like to use the 2.2 crank in the 2.5 block gives you a 2.35 destroker motor about 8.0-1 then turbo it cheap turbo engine with bulletproof bottom end.

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well. today i took the heads off of the ej25d that i had. here's the pics, what do you think? im still a bit novice when it comes to diagnosing things.

 

i see some of the valves are pretty white, would this be due to coolant seepage??

 

SGFsZXMgQ29ybmVycy0yMDEyMTIyMS0wMDE2MC5qcGc.jpg

SGFsZXMgQ29ybmVycy0yMDEyMTIyMS0wMDE1OS5qcGc.jpg

SGFsZXMgQ29ybmVycy0yMDEyMTIyMS0wMDE1OC5qcGc.jpg

SGFsZXMgQ29ybmVycy0yMDEyMTIyMS0wMDE1Ny5qcGc.jpg

SGFsZXMgQ29ybmVycy0yMDEyMTIyMS0wMDE1Ni5qcGc.jpg

SGFsZXMgQ29ybmVycy0yMDEyMTIyMS0wMDE1NS5qcGc.jpg

SGFsZXMgQ29ybmVycy0yMDEyMTIyMS0wMDE1NC5qcGc.jpg

SGFsZXMgQ29ybmVycy0yMDEyMTIyMS0wMDE1My5qcGc.jpg

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Steam cleaned!

That one clean piston is evidence enough, but the others look like they were starting to seep coolant as well.

Valves tend to take the same coloring as the spark plugs, a little white means that cylinder is lean. Properly running the valves will be grey but not heavily deposited, and the combustion chamber may have black/brown coloring. Lots of black crud could mean a rich mixture, and/or too many short trips. Basically the black carbon crud will burn off when the engine gets up to operating temp and stays there on a regular basis. A thin layer of carbon will build up on the piston crowns and will stay there unless the engine overheats, or a head gasket goes bad, in which case the carbon gets steamed off. It will start off in small spots, usually closest to the source of the leak.

 

Here's a good comparison. Left side was leaking coolant. You can see a small notch in the bottom left side of the fire ring. Right side is normal. IMG_0842.jpg

Edited by Fairtax4me

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i like to look down the exhaust pipes from heads to see how the burn was a light tan exhaust header port is normal any wet or oil or black or white deposits are i sign of oil or coolant burning. On the short block i rock the #2#4 pistons at tdc to check for slap if slopy the rest is probly slopy to

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were you referring to the one clean piston in the pic? i think i took a rag to the thing before taking the picture, it was consistant with the other pistons etc, the spark plugs were a little light on the front cyl's and darker on the rear cyls.

 

in any case, based on those pics, do you think that the head is decently useable? i didnt have any oil on the plugs at all so i think the rings are decent,

 

this car was used for a period of time for the guys wife who dove 5 mins to and from work each day. which would confirm your statement above about the short trips etc.

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Heads are generally re-usable with little work. Clean them and check for cracks in the combustion chamber. Make sure the valves close all the way. Put it back on.

If desired, now is a good time to replace valve stem seals.

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Heads are generally re-usable with little work. Clean them and check for cracks in the combustion chamber. Make sure the valves close all the way. Put it back on.

If desired, now is a good time to replace valve stem seals.

 

Oh crap. I meant to say 'block' not heads. :banghead:

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Block, kind of a toss-up. Biggest problem with the block is the rod bearings are easily damaged by overheating. Supposedly the 99 block is a phase 2 block that has larger rod bearings and should be more resistant to damage. Did you already drain the oil? Check it for shiny flakes.

 

If an engine gets overheated too badly the rear timing covers will deform. They end up with a melty/wavy look near where they bolt to the heads.

 

How do the cylinder walls look? Can you still see the cross hatching?

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i thought i recalled seeing some cross hatching, i'll have to double check in some good light. i havent drained the oil yet, so i can check that for goodies.

 

the rear of the tb covers were not warped at all. so... as long as they havent been replaced at some point

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In that case, flip a coin. Head gaskets are cheap. If you can keep an ear on the engine for funny knocking sounds that get progressively louder, you can slap Sir Frank together and have some fun for a while. It might start knocking right away, might take five or ten thousand miles, maybe it'll run until the car is rusted away. Hard to say.

I'd pull the oil pan off while its easy to get to and check real close for metal flakes in the bottom. Some glitter is normal, but if there is an abundance I'd just plan on putting new bearings in it. Another check is to wiggle the rod ends up and down perpendicular to the crankshaft. Any noticable movement is bad news.

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Dude, on schmaus's engine we had rust in 2 of the cylinders, pitting, and rotation resistance with the block that we assembled with after removing the heads. We managed to polish out the rust with PB blaster and the rings doing the cutting. So far the car runs great and does not smoke, for an engine that anyone else may have just thrown away.

 

Yours looks better, ours looks like it sat outside with standing water in the cylinders.

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Dude, on schmaus's engine we had rust in 2 of the cylinders, pitting, and rotation resistance with the block that we assembled with after removing the heads. We managed to polish out the rust with PB blaster and the rings doing the cutting. So far the car runs great and does not smoke, for an engine that anyone else may have just thrown away.

 

Yours looks better, ours looks like it sat outside with standing water in the cylinders.

 

holy crap! LOL that makes me feel better about my pile of stuff.

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In that case, flip a coin. Head gaskets are cheap. If you can keep an ear on the engine for funny knocking sounds that get progressively louder, you can slap Sir Frank together and have some fun for a while. It might start knocking right away, might take five or ten thousand miles, maybe it'll run until the car is rusted away. Hard to say.

I'd pull the oil pan off while its easy to get to and check real close for metal flakes in the bottom. Some glitter is normal, but if there is an abundance I'd just plan on putting new bearings in it. Another check is to wiggle the rod ends up and down perpendicular to the crankshaft. Any noticable movement is bad news.

 

 

word.

 

i think i'll just slap the frankenmotor together then, sounds like worse case, if i get some knocking and ************ i can just put the 2.2 block back in the middle.

 

the 2.2 is in the car, it starts, smokes a bit, its not blue, but its not necessarly rotten veggie smelling. hard to tell whats what when its 20 degrees outside, 2 of the plugs seemed to have some oil on them that we took out of it. i've taken it around the block a few times, it idles a little rough, but when you put on the gas or let off the gas, it seems to run rough. im gonna try cleaning up some things like the pcv and maf etc and see if that does anything for it. im getting pretty consistant spark on all cyls per my timing gun, i'll try to get a video driving it around so ya can see what im talkin bout.

 

so in the mean time i can checkout and clean up this 2.2 block while the f'nmotor is in

 

 

why do i do this ************ in winter. LOL

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So getting back to the question of interference on this frankenmotor setup.

 

anyone been able to try this out with the clay as mentioned above?

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All 2.5 bottom ends when coupled with 2.2 heads are interference. The 96 is MORE interference due to its flat top pistons. It's also a very bad candidate for a FM - the compression is over 12:1 and the ECU will totally freak out. The best FM is made with the '99 25D. Comp. ratio is 10.6:1 and they have 52mm rods. 97/98 are same comp. and 251/253 bottoms will yield about 11.5:1

 

GD

Edited by GeneralDisorder

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The 96 is MORE interference due to its flat top pistons. It's also a very bad candidate for a FM - the compression is over 12:1 and the ECU will totally freak out.

GD

 

Sounds oddly familiar

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thanks for chiming in GD, makes me happy bout my 99 block.. if in fact its the original engine to the car and is a 99. LOL.. i assume it is, is there any visual differences with the 99 block i can look at to make sure its infact a 99 block??

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Check the VIN etching on the bell housing. Tenth digit should be a X for 1999. This would tell you the model year of the vehicle the engine came from, if it is not original to the car.

Edited by Fairtax4me
Fixed incorrect letter/year designation

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99 block will be an 8 bolt bell-housing. It's the only 8 bolt dual cam N/A out there.... Well till you get into the H6's and newer FB/FA engines, etc.

 

It's really a 251 case/crank/rods with 25D pistons. A little trick on Subaru's part.

 

GD

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i couldnt find the vin at first on the block, had to get out the degreaser and a brush i found it, its a X, which per the decoder shows its a 99 motor, (plus the vin matches)

 

Thanks guys, im absorbing all these little notes about the differences. :headbang:

 

hey what are these markings on the block (mine are different but this was the only pic i could find showing them, i couldnt find any answer on the web or here

 

the 73 3 followed by a symbol. is that a piston designation?

SnipImage-1.jpg

Edited by xbeerd

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Check the VIN etching on the bell housing. Tenth digit should be a W for 1999. This would tell you the model year of the vehicle the engine came from, if it is not original to the car.

 

Sorry for this highjack but maybe this could be useful for others....

 

I have a 99 Lego OB EJ25 short block here with an "X" as the tenth digit. It was a DOHC & is 8 bolt bell-housing pattern. Don't know the mileage as the donor odometer was missing when I pulled it. Guess I'll find out the rod journal size when torn down for brgs/rings.

 

Were there any other variations to this tenth digit "W" designation?

 

Edit: xbeerd posted his "X" just as this post was being typed.:cool:

Edited by czny

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Sorry for this highjack but maybe this could be useful for others....

 

I have a 99 Lego OB EJ25 short block here with an "X" as the tenth digit. It was a DOHC & is 8 bolt bell-housing pattern. Don't know the mileage as the donor odometer was missing when I pulled it. Guess I'll find out the rod journal size when torn down for brgs/rings.

 

Were there any other variations to this tenth digit "W" designation?

i think he just goofed, W shows 1998. X for '99 per this site.. http://www.cars101.com/subaru/vin.html

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