.040 Over bore too much?
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.040 Over bore too much?
For my 2.35 I have to use .020 over bore pistons, thus I have to have it bored...
Now what I was thinking, why not go with .040 over bore and make the engine a 2.4L closed deck.
What do you guys think?
Now what I was thinking, why not go with .040 over bore and make the engine a 2.4L closed deck.
What do you guys think?
~Spencer
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Re: .040 Over bore too much?
smh0101 wrote:For my 2.35 I have to use .020 over bore pistons, thus I have to have it bored...
Now what I was thinking, why not go with .040 over bore and make the engine a 2.4L closed deck.
What do you guys think?
Sounds good to me except I believe Subaru factory says to not overbore beyond 0.020 inches. They're being conservative, of course. Also, check with your piston supplier and make sure they offer an oversize of 0.04...... I don't think all of them do. At 0.04 overbore I would definitely go with molybdenum coated skirts to reduce heat/stress as much as possible on the cylinder bores. It should be fine then.......... at least that's the theory.
What's your final setup going to be ?
.
EJ22 n/a installed in 1984 Volkswagen Transporter/Vanagon/Bulli
EJ22 motor with blown head-gasket undergoing rebuild to stock specifications
EJ22 motor with blown head-gasket undergoing rebuild to stock specifications
Wiseco, they make them for this build.
And its gonna be:
22t block
2.5L Phase 1 Crank/Rods
RS 2.5L DOHC NA Heads
vf39 or td05-16g
ej20g intake manifold
stock new subaru bearings
wiseco pistons
sti 565cc injectors
And its gonna be:
22t block
2.5L Phase 1 Crank/Rods
RS 2.5L DOHC NA Heads
vf39 or td05-16g
ej20g intake manifold
stock new subaru bearings
wiseco pistons
sti 565cc injectors
~Spencer
94 Legacy Turbo (550 Robtune/ej20h v2 Sti RA drivetrain)
94 Legacy Ti Wagon (5mt ej22e)
91 rhd Legacy GT Wagon (factory 5mt, ej20g)
93 rhd Legacy GT type S2 Sedan (4eat, ej20g)
91 rhd Legacy Ti Type S 1.8
03 Lincoln LS V8 Sport
08 300 SRT8
94 Legacy Turbo (550 Robtune/ej20h v2 Sti RA drivetrain)
94 Legacy Ti Wagon (5mt ej22e)
91 rhd Legacy GT Wagon (factory 5mt, ej20g)
93 rhd Legacy GT type S2 Sedan (4eat, ej20g)
91 rhd Legacy Ti Type S 1.8
03 Lincoln LS V8 Sport
08 300 SRT8
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You could probably get away with it...but .040 is a big cut...and will pretty much render your block useless for future boring. Keep in mind that it is really double the necessary clean-up bore...which is why Wiseco makes those pistons in .020.
Have you done the math to find that twenty thousandths more per hole will actually increase the displacement by 1/20th of a liter?!?
Have you done the math to find that twenty thousandths more per hole will actually increase the displacement by 1/20th of a liter?!?
Nick
1987 Audi 4000CS quattro...soon to be 20VT
1994 Dodge Ram 2500 4x4 CTD, #11 plate, 30 psi, Scotty II intake, 4" exhaust
1987 Audi 4000CS quattro...soon to be 20VT
1994 Dodge Ram 2500 4x4 CTD, #11 plate, 30 psi, Scotty II intake, 4" exhaust
Nick beat me to it.
You will never notice (seat of pants) that extra displacement.
Being able to clean up the block again should you have a meltdown is far more valuable.
If your looking for a DynoQueen, by all means bore it out.
You will never notice (seat of pants) that extra displacement.
Being able to clean up the block again should you have a meltdown is far more valuable.
If your looking for a DynoQueen, by all means bore it out.
'93 Winestone SS Auto, '91 Pearl White SS.
'93 Pure White SS EJ20G slanty intercooled, SIDESWIPED! In stasis.
'94 FWD and '95 AWD Laguna Blue SVXs.
2017 Pure Red BRZ Limited w/Performance pack
'93 Pure White SS EJ20G slanty intercooled, SIDESWIPED! In stasis.
'94 FWD and '95 AWD Laguna Blue SVXs.
2017 Pure Red BRZ Limited w/Performance pack
haha, no. I want drivability, screw dynos!
Mmkay, sticking with .020!
Mmkay, sticking with .020!
~Spencer
94 Legacy Turbo (550 Robtune/ej20h v2 Sti RA drivetrain)
94 Legacy Ti Wagon (5mt ej22e)
91 rhd Legacy GT Wagon (factory 5mt, ej20g)
93 rhd Legacy GT type S2 Sedan (4eat, ej20g)
91 rhd Legacy Ti Type S 1.8
03 Lincoln LS V8 Sport
08 300 SRT8
94 Legacy Turbo (550 Robtune/ej20h v2 Sti RA drivetrain)
94 Legacy Ti Wagon (5mt ej22e)
91 rhd Legacy GT Wagon (factory 5mt, ej20g)
93 rhd Legacy GT type S2 Sedan (4eat, ej20g)
91 rhd Legacy Ti Type S 1.8
03 Lincoln LS V8 Sport
08 300 SRT8
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I was in the same boat. I chose the .020 overbore for the fact that I can always take it out a little more if the need arised. Its not worth the .04 liters. Plain and simple.
If you want to get serious like that send your block to Darton. They'll hook you up with a 2.65L. Or Ron at what used to be Axis.
If you want to get serious like that send your block to Darton. They'll hook you up with a 2.65L. Or Ron at what used to be Axis.
→Dan
piddster34 at h0tma1l d0t c0m
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