Opinions for dohc swap

Heads, valves, pistons, rods, crankshaft, etc...

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Subiepoo11
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Location: Denver, Colorado
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Opinions for dohc swap

Post by Subiepoo11 »

Hi guy,
Im just want to hear your opinions on what r the best heads to use for a dohc swap. Ive heard ej25d's are what most people use. What kinda power can you make off these.
Thanks
Thesubielover
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Joined: Tue Feb 14, 2012 11:20 am
Location: Seattle, WA

Re: Opinions for dohc swap

Post by Thesubielover »

Ive been told to swap with the ej20 heads and ej20 manifold with the ecu. I guess this set up could handle around 325-400hp. Im interested to hear other suggestions as I am looking at doing a swap in the future as well.
93ss 3inch tbe, Hallman mbc,06 wrx td04, tmic, bov, bugeye seatsStolen x2, sold
93ss Stroker,440cc inj, VF39, '06 TMIC, EJ20G heads & intake, EJ25 crank, 4.11Traded
93ss 4eat, coils, stanced, wraped, flat black, stock show car
PhyrraM
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Location: Lake Elsinore, CA

Re: Opinions for dohc swap

Post by PhyrraM »

From somebody who has been there...

Buy a complete EJ20G from a '89-'93 Legacy or a '92-'96 Impreza WRX/STI.

Reasons:

It all bolts in and looks factory. 100% compatable with the Legacy engine bay.
It has all the "little" pieces that take a TON of time and effort to track down if you just want to "buy heads and manifold".
It will run on the factory ECU, if needed. It will also work with an EJ20G ECU on the factory harness.
It will support better heads and different shortblocks if/when you go beyond the stock 2.0 size.
It has all the "little" pieces that take a TON of time and effort to track down if you just want to "buy heads and manifold".
The EJ20G intake manifold is still arguably one of the best Subaru made.


Reasons not to:

Extra "up-front" money to purchase a complete motor that some may not have.
Newer turbos need a 90 degree intake adapter.
Most upgrades need to come from overseas. (silicon hoses, intercoolers, etc.)


To directly answer your question: The EJ20K STI heads are generally considered the best of all the phase 1 heads. However, all are good. EJ20D heads *should* get turbo cams (debated).
'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
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