Trying to get STI pistons to work....
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The STI pistons are made so that the area that the top of the rod fits into gets narrow, so the tops of the rods must be angled to fit.
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1990 wagon, EJ25 12.3 @ 116.5 FAST Family wagon getting new motor soon
1992 wagon, wifes daily, high compression
1992 Touring wagon, should I keep it?
I was wondering why you were milling at an angle on a rotary table....douglas vincent wrote:The STI pistons are made so that the area that the top of the rod fits into gets narrow, so the tops of the rods must be angled to fit.
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OK, I commited.
Its going together with the HUGE deck to piston gap......
I DID pin the cylinders to the block though with brass 5/16" pins.....
And the rods are connected to the crank, I would have it done, but I forgot to by block goo, be done tomorrow morning.
Its going together with the HUGE deck to piston gap......
I DID pin the cylinders to the block though with brass 5/16" pins.....
And the rods are connected to the crank, I would have it done, but I forgot to by block goo, be done tomorrow morning.
Reddevil, Awaiting new heart, will it ever happen?
1990 wagon, EJ25 12.3 @ 116.5 FAST Family wagon getting new motor soon
1992 wagon, wifes daily, high compression
1992 Touring wagon, should I keep it?
1990 wagon, EJ25 12.3 @ 116.5 FAST Family wagon getting new motor soon
1992 wagon, wifes daily, high compression
1992 Touring wagon, should I keep it?
im so confused as to what your doing.
first off phase2 rods are 52mm crank journal and phase 1 is 48mm so you have to have mathching crank and rod bearing sizes. also 2.5 is the shortest rod see stroker application??
so yeah im confused.
first off phase2 rods are 52mm crank journal and phase 1 is 48mm so you have to have mathching crank and rod bearing sizes. also 2.5 is the shortest rod see stroker application??
so yeah im confused.
-jason
[quote="Scoobyniteowl"] Chasin' @$$ is a great form of exercise and if you do get any, then that is more exercise[/quote]
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Pretty sure that 2.5 rods are the longest ones. The piston pin location is raised closer to the crown to compensate.
A 2.5 piston has the pin almost in the oil control ring if I'm not mistaken.
A 2.5 piston has the pin almost in the oil control ring if I'm not mistaken.
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quote worthydouglas vincent wrote:Its my God Given Duty to confuse asian people.
Josh
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cylinder pinning is sweet!
did you pre drill or is it a really tight press fit? only worry with really tight it that its possibly doing something to the bore roundness or something. i think I can see some pre drilling but not sure.
how about adding a couple more, overkill?
did you pre drill or is it a really tight press fit? only worry with really tight it that its possibly doing something to the bore roundness or something. i think I can see some pre drilling but not sure.
how about adding a couple more, overkill?
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I used a hand drill and a 5/16th REAMER. A reamer gives a much better round hole and is "easier" to drill with.
Then I used my little lathe and turned 3/8" rods of brass down to individually fit each pin. Then I tapped them down.
The block may or may not be out of round now, but I dont really care because this is a test build just to see if it works. If I have to do another one, then I will take the block to a machine shop and have it bored.
Then I used my little lathe and turned 3/8" rods of brass down to individually fit each pin. Then I tapped them down.
The block may or may not be out of round now, but I dont really care because this is a test build just to see if it works. If I have to do another one, then I will take the block to a machine shop and have it bored.
Reddevil, Awaiting new heart, will it ever happen?
1990 wagon, EJ25 12.3 @ 116.5 FAST Family wagon getting new motor soon
1992 wagon, wifes daily, high compression
1992 Touring wagon, should I keep it?
1990 wagon, EJ25 12.3 @ 116.5 FAST Family wagon getting new motor soon
1992 wagon, wifes daily, high compression
1992 Touring wagon, should I keep it?
What about thermal expansion?
I'd have to look and see what the differences between brass & aluminum are, but if they are reasonably different, then all the work could not do squat, or it could hurt you.
Ideally, you'd want to use a material that has the same thermal coefficient as the block material.
I'd have to look and see what the differences between brass & aluminum are, but if they are reasonably different, then all the work could not do squat, or it could hurt you.
Ideally, you'd want to use a material that has the same thermal coefficient as the block material.
Josh
surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT
If you need to get a hold of me please email me rather then pm
surrealmirage.com/subaru
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2020 Outback Limted XT
If you need to get a hold of me please email me rather then pm
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+1Legacy777 wrote:What about thermal expansion?
I'd have to look and see what the differences between brass & aluminum are, but if they are reasonably different, then all the work could not do squat, or it could hurt you.
Ideally, you'd want to use a material that has the same thermal coefficient as the block material.
If I recall correctly, brass has a much lower thermal coefficient than aluminum...
Nick
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Surface area really doesn't matter, the thickness of the material does.
I looked in one of my books and here's what they have for the average coefficients of linear thermal expansion:
Aluminum Alloy = 12.8 x 10^-6 (1/(deg F))
Brass = 10.0 x 10^-6 (1/(deg F))
If you work out the thermal deformation equation for area, you get the following change in area for each material:
Aluminum Alloy = 2.55 x 10^-4 in^2
Brass = 1.99 x 10^-4 in^2
Those are pretty small numbers, and the difference between them is even smaller. However if it were me, I'd still probably do some looking into things....but you'll probably be fine.
I looked in one of my books and here's what they have for the average coefficients of linear thermal expansion:
Aluminum Alloy = 12.8 x 10^-6 (1/(deg F))
Brass = 10.0 x 10^-6 (1/(deg F))
If you work out the thermal deformation equation for area, you get the following change in area for each material:
Aluminum Alloy = 2.55 x 10^-4 in^2
Brass = 1.99 x 10^-4 in^2
Those are pretty small numbers, and the difference between them is even smaller. However if it were me, I'd still probably do some looking into things....but you'll probably be fine.
Josh
surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT
If you need to get a hold of me please email me rather then pm
surrealmirage.com/subaru
1990 Legacy (AWD, 6MT, & EJ22T Swap)
2020 Outback Limted XT
If you need to get a hold of me please email me rather then pm
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With the way Doug goes through motors electrolytic corrosion won't be an issue.
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