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Discussion Starter · #1 ·
So my 2012 gs eclipse threw a bearing that is my current assumption. Do not yet know what I’m gonna be dealing with when the engine is pulled but lots of metal in my oil. As long as the block is not messed up I plan on boring it out and getting a rebuild kit as well as possibly some performance mods. Any recommendations on good quality rebuild kits? This is my daily driver so I need something that will last but wont break my bank account.
 

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Basically Stock
2009 GS Turbo. 2007 Mid Engine GT
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shrug
I'm pretty much the only guy that sells a 4G69 bottom end kit.

87.5mm bore forged pistons
tri layer main/rod bearings
thrust washers
forged rods
Head studs and main studs

Hopefully your crank is good. You probably don't want to enter the world of aftermarket cranks. Expensive, and sensitive

All comes together for an ~600hp rated bottom end on the stock head. Lots of boosted guys run the setup, nobody has broke from too much power. Cap yourself around 30-35psi. With better head flow, it'll make more power.
 

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Discussion Starter · #3 ·
my current plan is to get an evo turbo exhaust manifold and turbo it then tune it on racing fuel, would all that be able to handle the boost and tune? Also would that come with all the hardware and where could I find a link to it?
 

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Basically Stock
2009 GS Turbo. 2007 Mid Engine GT
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How budget? You may need to set your goals lower or save up longer. 400 can happen on a stock GS motor, but is at high risk of damage. Stock clutch won't hold, you'll need an fx350 minimum. Fuel pump won't do it rich enough on a stock motor to keep it safe, and you'll need to go to a return fuel setup (~$800 if using pfte grounded fuel line as you should). Tuning with fast works will be $550. The turbo itself will either not be worth buying, or $800+. Your charge piping and a half decent eBay intercooler will be $300-$400. Boost controller will be $100+, cheap bleed style aren't very nice as they control very poorly. Something like an e boost street will give you a gauge and controller in one. Motor mount bushings will need to be stiffened. 3 bar map sensor. You'll need a bigger custom MAF housing to pass 340whp. Exhaust manifold is $650 I believe if you don't make your own (supports t3 flange). You'll want a 3" exhaust including downpipe optimally. You'll need a good wideband o2 sensor and gauge ($240ish). You'll need larger fuel injectors, look into some 1000cc at that point ($300ish for decent ones). And engine kit is about $1500, I think $1540 with the most recent price increase from Brian Crower (happening almost monthly now).

400 is in the territory where it costs about the same to make safely as 550. If you drop your goal to ~340, a lot of that list goes away
 

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Basically Stock
2009 GS Turbo. 2007 Mid Engine GT
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Stock things ok with 340whp:
Engine block/head
MAF
Fuel pump
Stock spark plug heat range (NGK iridium run nice at 0.028" gap)
Manual trans
Cooling system
Axles


Stock things not ok:
Fuel injectors (565cc WRX top feed low impedance ones work, watch out for eBay fakes, they won't work)
MAP sensor (use an Evo 8/9 one, unsure about 10. Stock (1 bar) can't do ANY boost, Evo (3 bar) sensor won't work without tuning)
Motor mount bushings (go poly)
Stock exhaust (You'll want to go at least 2.5" from the turbo back)
Stock clutch
Auto trans

Additional things:
Boost controller
Charge piping
Intercooler
Wideband O2 sensor
Tuning
 

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Basically Stock
2009 GS Turbo. 2007 Mid Engine GT
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Stock block generally refers to everything inside it as well.

But for clarity, stock main bearings, rod bearings, thrust washers, main bolts, main cradle, pistons, piston rings, crankshaft, and rods will do 340whp.

Beyond that, for clarity, the stock head is fine, stock intake manifold is fine, head gasket is fine. You will want to block off your EGR passage at the intake manifold, however.
 

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Discussion Starter · #13 ·
I did have one more question, I’ve been looking through older threads and such but I have a AT gs, gonna need to swap it cause I am not sure about being able to build out an auto trans. Are there any other manual transmissions that will fit and work in it? I saw an earlier thread about the possibility of the 3g manual tranny being identical but haven’t found anything else.

I know manual swapping is a ton of work for something that may not even work and if so then it’s a hard pill to swallow. Is there any way to build out the auto to handle the turbo and more hp?
 

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I did have one more question, I’ve been looking through older threads and such but I have a AT gs, gonna need to swap it cause I am not sure about being able to build out an auto trans. Are there any other manual transmissions that will fit and work in it? I saw an earlier thread about the possibility of the 3g manual tranny being identical but haven’t found anything else.

I know manual swapping is a ton of work for something that may not even work and if so then it’s a hard pill to swallow. Is there any way to build out the auto to handle the turbo and more hp?
Definitely interested in the response to this one, feel like auto trans users are all in the same boat
 

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Basically Stock
2009 GS Turbo. 2007 Mid Engine GT
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Definitely interested in the response to this one, feel like auto trans users are all in the same boat
None of these are CORRECT, but multiple can be made to work.

3G GS (gear ratios wrong, weaker)
Lancer Ralliart (4G69 version from 2004ish) (gear ratios wrong, weaker)
Evo 7/8/9 (With AWD swap) (ratios wrong, 5 speed is similar, 6 speed is weaker)

On all the options, 1-2-3 are the physically large strong gears. 6 speed loses out as 1-2-3 are shorter than the 5 speed so it spends more time in 4th on a racetrack, plus the 4-5-6 gears are made to fit in the same space that the 4-5 is on a 5 speed, giving physically smaller gears that don't handle the torque as well as 4-5 on a 5 speed (which is still their weak point)
 

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I want to be able to push at the very least 400 but this is a budget build and I cannot pour all my money into it I just want some decent power.
....you've picked the absolute wrong vehicle then, a 400whp gs budget build, now that's a very nice thought... you'd be better off getting an 84-89 300zx. 2500$~ and you can make 400rwhp stock bottom and upper end. I love my GS, so much that I've fixed it at every point that it let me down. They're nice to cruise around and the handling is very very wonderful. If you've really spun a bearing, you can drop the pan and look at the crank in all of 15 minutes. I've swapped bearings out in the driveway in a matter of a few hours.
 
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shrug
I'm pretty much the only guy that sells a 4G69 bottom end kit.

87.5mm bore forged pistons
tri layer main/rod bearings
thrust washers
forged rods
Head studs and main studs

Hopefully your crank is good. You probably don't want to enter the world of aftermarket cranks. Expensive, and sensitive

All comes together for an ~600hp rated bottom end on the stock head. Lots of boosted guys run the setup, nobody has broke from too much power. Cap yourself around 30-35psi. With better head flow, it'll make more power.
What is all this stuff? I've heard of boring vs stroke and what they do but could you explain what they do just for laymans? I will do some research on this just to know more not sure if I would do this but it sounds cool!
 

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Basically Stock
2009 GS Turbo. 2007 Mid Engine GT
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7,617 Posts
What is all this stuff? I've heard of boring vs stroke and what they do but could you explain what they do just for laymans? I will do some research on this just to know more not sure if I would do this but it sounds cool!
BORING is the act of machining the bore larger. I don't think that's what you wanted to know though, so I'll guess

BORE is the diameter of the cylinders in the engine
STROKE is the measured distance of how far the piston moves up and down, which is twice the distance that the crankshaft journal (where the rod connects to) is from the main journal (center of the crankshaft where it connects to the engine). The reason it's double is because as the crank rotates, it moves up, and down, full circle.


Engines with a big bore and low stroke are called oversquare, and are good for high RPM in general. Sport bike engines are usually made like this. A bore:stroke ratio around 2 isn't uncommon on those. Eg, 50mm bore, 25mm stroke. The reason is, air flows in a mostly straight path, and goes in and out quickly. Unfortunately, they're limited by burn times of the fuel, and very inefficient as they just dump the most heat energy out the exhaust of the types. The Eclipse GT is oversquare (95mm bore 90mm stroke)

Engines with an equal bore:stroke are called square. Not uncommon on cars. It's a nice balance of power and efficiency. 1:1, eg 86mm bore 86mm stroke on a Toyota 2JZ motor

Engines with a small bore and long stroke are called undersquare, and are good for low RPM. They don't breath air in and out very fast, but are very thermally efficient in that they create the most force from the chemical energy (fuel) put in. Eg, 75mm bore 85mm stroke on a Prius. The Eclipse GS is undersquare (87mm bore 100mm stroke)


Slope Rectangle Parallel Font Plot






I may have totally misunderstood what you're asking here,going back and re-reading it, but I'm keeping the lesson I wrote above, lol.

The engine parts I sell:
Pistons: They cool faster than the stock ones, have lower compression (less knock chance, more bias towards high RPM power), more knock resistant. 87.5mm bore not for power gains, but to get a proper seal. You ALWAYS custom machine an engine to match the pistons
Rods: Knock resistant, allows you to slam on a lot of torque very early with a turbo, unlikely to bend one below ~700ft-lb of torque, unlikely to come apart below 8500rpm
Head studs: Keep the head from lifting under high cylinder pressure
Main studs: Keep the main cradle from shifting under high load from RPM or torque
Tri layer bearings: More knock resistant, will handle more crankshaft contact under high RPM/torque without denting then coming apart
 

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BORING is the act of machining the bore larger. I don't think that's what you wanted to know though, so I'll guess

BORE is the diameter of the cylinders in the engine
STROKE is the measured distance of how far the piston moves up and down, which is twice the distance that the crankshaft journal (where the rod connects to) is from the main journal (center of the crankshaft where it connects to the engine). The reason it's double is because as the crank rotates, it moves up, and down, full circle.


Engines with a big bore and low stroke are called oversquare, and are good for high RPM in general. Sport bike engines are usually made like this. A bore:stroke ratio around 2 isn't uncommon on those. Eg, 50mm bore, 25mm stroke. The reason is, air flows in a mostly straight path, and goes in and out quickly. Unfortunately, they're limited by burn times of the fuel, and very inefficient as they just dump the most heat energy out the exhaust of the types. The Eclipse GT is oversquare (95mm bore 90mm stroke)

Engines with an equal bore:stroke are called square. Not uncommon on cars. It's a nice balance of power and efficiency. 1:1, eg 86mm bore 86mm stroke on a Toyota 2JZ motor

Engines with a small bore and long stroke are called undersquare, and are good for low RPM. They don't breath air in and out very fast, but are very thermally efficient in that they create the most force from the chemical energy (fuel) put in. Eg, 75mm bore 85mm stroke on a Prius. The Eclipse GS is undersquare (87mm bore 100mm stroke)


View attachment 103894





I may have totally misunderstood what you're asking here,going back and re-reading it, but I'm keeping the lesson I wrote above, lol.

The engine parts I sell:
Pistons: They cool faster than the stock ones, have lower compression (less knock chance, more bias towards high RPM power), more knock resistant. 87.5mm bore not for power gains, but to get a proper seal. You ALWAYS custom machine an engine to match the pistons
Rods: Knock resistant, allows you to slam on a lot of torque very early with a turbo, unlikely to bend one below ~700ft-lb of torque, unlikely to come apart below 8500rpm
Head studs: Keep the head from lifting under high cylinder pressure
Main studs: Keep the main cradle from shifting under high load from RPM or torque
Tri layer bearings: More knock resistant, will handle more crankshaft contact under high RPM/torque without denting then coming apart
This is really great info man I appreciate it, I knew what bore and stroke was but not to the level of what you explained. I will definitely research a bit more about engines before I would ever do anything like modify the engine parts directly. Would this kit work under stock conditions? Or would you have to modify fuel output to be able to match with a larger bore? Can you run this kit N/A or is it for forced induction only? Thank you and sorry for the constant questions I really appreciate the knowledge!
 
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