Page 1 of 1

Replacement engine - rebuild questions?

Posted: Wed Sep 16, 2009 12:18 am
by ScottyS
So, I want to have a "hot spare" sitting in the garage now that I have gotten the car basically under control and running like I want. I don't want to spend a TON of money building a motor from the ground-up, I'm not racing the darn thing. But, knowing very little about engine machining/building in general, I am at a loss as to what to do with the parts I currently have.

Let's assume for sake of simplicity that I can take care of the tuning/engine management side of things for now, and just focus on the hardware.

Here's what I have sitting around:

1) EJ20G probably from a Legacy, it had a VF-8 that came with it, and it was attached to an automatic tranny. Block, heads, intake manifold are all there and still assembled. I took the injectors off for my Stage 2 upgrade.

2) EJ22T block with a separated crankshaft. This was the motor in the car when I bought it, I removed the heads with the intention of splitting the block and having it checked, I have not gotten there yet,

3) EJ22T motor from the wrecking yard. 150k miles. The car took a frontal/oblique impact in dirt, pushed the frame corner into the front of the motor by the oil fill. The head is clearly cracked at the front cam seal, but I am optimistic about the state of the block.


So, I basically need to verify the integrity of the 22T blocks. What I don't know is if I need to take them both all the way apart or not.

Then, what sort of machine work should I expect to have done? What would essentially take a used block to the point where it's ready to go 200k mi again?

Head-wise, from what everyone says the stock heads are limited, even if you spend money on cams, P&P, etc. I could use the 20G heads I have and find a 25D intake I suppose. What should I look at doing to the 20G heads if I want similar longevity to a rebuild block? What if I want to improve the redline? Or, should I find some USDM DOHC heads for cheap somewhere instead?

Again, the goals would be: cost-effective improvements that are easy to do while everything is apart, higher redline, 100k mile+ longevity.

What Would Matt Monson Do?

Posted: Thu Sep 17, 2009 5:27 pm
by Legacy777
What type of power do you want to make and how much do you want to spend?

Posted: Thu Sep 17, 2009 6:05 pm
by ScottyS
Legacy777 wrote:What type of power do you want to make and how much do you want to spend?
I really don't have a budget, I'm just trying to keep it low and use parts I already have. Power-wise, I'm eventually expecting to be able to use a VF39-class turbo at moderate boost levels with 550cc-class injectors.

I guess a more targeted question would be - if I have a used block with over 100k miles on it, what should I do to it at minimum before putting it together and running it?

Posted: Thu Sep 17, 2009 6:10 pm
by Legacy777
Well....I can let you know what I did and you can go from there.

My ej22t block had 130k miles or something like that. I tore it down, had the cylinders rehoned, put new bearings, pistons, & gaskets in, and had the heads rebuilt. Other than that....I didn't do anything else. Even that will run you a couple grand.

If you didn't want to split the block or rebuild the heads, you could just take the heads off and see how the cylinders look and make your decision from there as to whether you want to pull the block halves apart.

My personal philosophy is to try and do as much as you can while you're in there or have things apart so you don't have to take it apart again in 6 months for a stupid $1 o-ring you didn't replace. It may cost a little more upfront, but will cost a lot more if you have to do it later.

Posted: Fri Sep 25, 2009 12:11 am
by ScottyS
OK, here's the present plan so that I have an "interim" motor. I'd like to build one all up and stuff, but quite frankly I'm not enthusiastic about putting that much dough into this shell (I'd rather do it with a GF Impreza or a 98GT wagon frankly).

EJ20G Legacy heads
EJ25D manifold (the only part I don't currently have)
EJ22T block

This is assuming that both the heads and the block look OK when I take the respective engines apart.

It looks like re-using the 20G headbolts is the way to go?

Posted: Sat Sep 26, 2009 2:22 pm
by Matt Monson
Matt Monson would put the Ej20G into the car just as it sits and start driving it. Then he would take his own sweet time with rebuilding the Ej22T bottom end. Then he would decide that it's time to settle down and get married and buy a house, so he'd sell his pride and joy of a '91 SS with an EJ20G swap to help cover the down payment on his home.

Oh wait. I am Matt Monson and that is what I did. I think that warrants both a :-D & a :( .

But in all honesty, if I were in your shoes, I'd do the same thing I did last time. I never got around to rebuilding the Ej22t (actually it made it onto my engine stand 2 weeks ago after a year and a half under a tarp in the corner of the garage. But that's a story for another day). But that seems like the best approach to my reckoning.

My swapped SS with an Ej20G, slanty intercooler, td04, and bone stock SS ECU running 12 psi made 240chp. I was happy with it. It's a big part of why I never took the next step before I sold it. I just didn't feel the call for more power once it was in the car. My gas mileage went up. I had 80 more hp than stock. And I startled more than a few WRX and Neon-SRT owners with my performance.

That's my 2 cents. I'll also answer your pm when I've got a bit more motivation. There's a couple things in there that are different than what you say here that I want to address directly and specifically

Posted: Sun Sep 27, 2009 3:23 am
by ScottyS
Thanks Matt, I'm trying to decide what to do. I've also thought about running the 20G with the 22T ECU and sensors, I'm just not sure what would happen since I am running the Revtronix chip, and it was tuned for the higher displacement. It might be worth a try though.

Since I've got an extra 22T block I thought that I could rebuild that one while this interim build was in the car.

But, it I will already make more power with the 20G bottom end (maybe due to compression differences?), then I'd be fine with that too. Maybe just find a 25D intake manifold so that I can run the USDM TMIC.

I've already got the wife and kids, so that part is out of the way!