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Discussion Starter #1
hey guys, I need some help down here :borgsmile I know some people here did the ej20h swap to thire cars, but cann't find anyone who went ej20h shortblock with sohc heads! I did my search but no results :confused:
anyway, I'm doing this cuz I need to keep the same wiring setup of my car, but I have some Q's before I start on this project on my RS.

1- I want to have 300+whp, how can I achive this with minimum $$ spent?
2- I know that I have to single turbo this engine, do I need to have wrx engine crossmember! or can I use my current one along with custom made up/down pipes!
3- will my gearbox be able to hold 300+whp!
4- EJ20H shortblock + EJ25 sohc heads, with good management, how much the redline you suggest, and how much is maximum safe boost on 97 oct fuel!


:noes: please help me, I know I feel like stupid with these questions :wtf:
 

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2000 Slingshot RS-T
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Do you have the shortblock already? Why not just use a 257 block instead.
Crossmember depends on what pipes you run. Stock RS crossmember will require custom piping.
What gearbox do you have? You can hold 300whp on stock tranny, it's just how you drive the car.
SOHC heads stock cams suck at top of the powerband. If you wanna rev the crap out of those heads, you will need cams + springs.
 

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If you had to do it all over again wedge, would you have simply bought a set of JDM RA heads?


Seems to me like the more cost-effective way to get a better cam profile and higher rev-limit.




EDIT: Did they change some sort of cam sensor between the phase 1 and 2 engines? Coulda sworn I heard that somewhere...
 

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Discussion Starter #6
Wedge said:
Do you have the shortblock already? Why not just use a 257 block instead.
Crossmember depends on what pipes you run. Stock RS crossmember will require custom piping.
What gearbox do you have? You can hold 300whp on stock tranny, it's just how you drive the car.
SOHC heads stock cams suck at top of the powerband. If you wanna rev the crap out of those heads, you will need cams + springs.
I would like to go 257, but the ej20h are damn so cheap here ( ej20h longblock+4AT trans....etc just for $300 ! ) and since I hate to do wiring stuff I will only use the shortblock, and sell the other suff that I don't need.
I don't think that I need to change the crossmember, cuz I have an extra turbo kit for the 2.5rs setting in my garage right now,,,,, I don't want to be limited to 6psi, so thats why I'm thinking of this setup, but how much boost can I push it without damaging it!
my rs gearbox is completly stock, but I will upgrade my clutch soon to make it able to handle 300whp
 

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2000 Slingshot RS-T
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Let me clear something up with the previous post.

That write-up is meant for a person using a Legacy Turbo, meaning the car already was wired for the EJ22T heads.

We, on the other hand, are coming from a car that uses the EJ25 heads, and just switching the shortblock. Painless.


To the OP. You could just get pistons for the stock EJ25, and be done with it.
 

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95 RHD WRX
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eh20h converted to single turbo td05-16g, turboback exhaust(no cats), apexi intake, PowerFC or Reflash running 1.4 bar with 100octane and larger injectors. 300whp easy =]
 
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