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Discussion Starter #1
I am starting my research: I am planning on building a factory five Subaru powered kit. It is very exciting a car that is mid engined and a finished weight under 2000#

Please help I can use a donor car from 02 to 07 but I would like direction on pros and cons for engine and tranny for the specific years. The only resriction as I understand it is we have to use the 5 speed the 6 speed want fit.

This will be a street legal toy that I intend to race scca, I hope 350 reliable horsepower is realistic, 400 would be extraordinary but $$$ and reliability are a concern

I am new to the subaru powerplant and am anxious for some direction
Thnaks in advance for any advice
 

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Pro Manscaper
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I'm guessing Factoryfive is the kit...which one specifically? Give us more details about exactly what you want for this project. Pics, links, etc. all will help.

For 350 reliable HP, you'll probably looking for an EJ257 STI powerplant with the VF39 or better turbo, with stage two plumbing and tuning of course (just do a quick search on that)...and that will be at the crank. If you want those numbers at the wheels, you will need better than a stock Subaru turbo.

...as to how to fit that to a kit car is beyond me unfortunately, but it sounds like a fun project.
 

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Factory Five makes a lot of different kit cars, so it would help to know details.

The Subaru 5 speed tranny isn't reliable to those numbers, and I'm curious why a 6 speed won't fit. The two trannies are a direct swap in Subarus so it doesn't make sense that you can use the 5 but not the 6.
 

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The Fruit
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the 6mt is wider than the 5mt isn't it? case wise? ..that may be why it wont fit. But then again.. if the car is that light the 5mt may not have as many issues as it does attempting to push another 1000lbs of car.
 

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if you want shorter ratios, 04-05 would be your choice in transmission... if you want longer ratios, the 06-07 had taller gears.

Is this going to be awd, or rwd?
 

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Discussion Starter #6
thanks

The kit is called the 818 project, it looks like it will be available in 2012 or 2013 which gives me time to save and learn, thank you for the info on 5 sp tranny and EJ257 with vf 39.
I was thinking about trying to buy a donor car and using it until it needs to be torn down, can you recommend years (I like the close ratio option) and I know the sti power plant may be the best option, however can I get into a 05 ish wrx and when it comes time just build the engine or is that going to be more work and money than going with the sti powerplant from the beggining?

Thanks again for the help
 

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Æternum
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The Subaru 5 speed tranny isn't reliable to those numbers.
5spd will be just fine at 350 chp, assuming it's not abused. 350whp might be pushing it, but if the wheel diameters are smaller on the kit car vs. the WRX (which is typically the case), it has the effect of gearing down the F/D. A kit car with 350whp, smaller wheels, and a 5spd might be just fine... especially if it's 2WD w/ the front diff removed, welded center diff, and plugged half-axles.
 
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