Jump to content
LegacyGT.com

Experts please help: OEM short block or build a block?


Recommended Posts

Here is the deal, 2005 LGT 5MT, 267k miles original block. Currently have supporting mods and dyno tune making 302 WHP/ 326 WTQ. Max I would go is 400/400. Still have to do a leak down test, but think I might need a new short block.

 

 

How much WHP can a stock OEM EJ255 handle?

 

 

If I end up needing a new short block I'm looking at which direction to go and looking for advice.

 

 

I have the ability to build my own setup. I have tools and specs as well as a helping hand to build my own EJ255. That is a whole other matter what I should all put into it. Rods, Pistons (cast vs Forged). I'd do new case halves and crank.

 

 

Other option is stock EJ255 or EJ257 and call it a day.

 

 

I'm looking to keep the cost down. I will have the whole thing professionally dyno tuned.

 

 

 

Any help or point me in the correct direct is appreciated.

Link to comment
Share on other sites

350 is normally what we say for a OEM ej257. the new RA block may go a bit higher.

 

Do you really need that much HP if this is a DD ?

 

I'm making 280AWHP and the car is a blast to drive and very reliable.

305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD).  CHECK your oil, these cars use it.

 

Engine Build - Click Here

Link to comment
Share on other sites

  • 4 weeks later...

I wouldn't touch the heads or block under 400whp. I also wouldn't run an off the shelf type tune or a remote tune seeing how these processes work compared to a proper Dyno/street tune

 

If you're that high mileage and doing your own labor slap some new bearings in and rehone the cylinders. Change out your valve seals and reseal the engine, replace oil pan pickup during reseal.

Deck and pressure test heads.

 

If you're paying a shop labor it's probably cheaper to just get an oem short block.

If you have a 2.5 that isn't living @ 350-400 it's probably not the engines fault

Link to comment
Share on other sites

Here is the deal, 2005 LGT 5MT, 267k miles original block. Currently have supporting mods and dyno tune making 302 WHP/ 326 WTQ. Max I would go is 400/400. Still have to do a leak down test, but think I might need a new short block.

 

 

How much WHP can a stock OEM EJ255 handle?

 

 

If I end up needing a new short block I'm looking at which direction to go and looking for advice.

 

 

I have the ability to build my own setup. I have tools and specs as well as a helping hand to build my own EJ255. That is a whole other matter what I should all put into it. Rods, Pistons (cast vs Forged). I'd do new case halves and crank.

 

 

Other option is stock EJ255 or EJ257 and call it a day.

 

 

I'm looking to keep the cost down. I will have the whole thing professionally dyno tuned.

 

 

 

Any help or point me in the correct direct is appreciated.

 

 

Also just curious why would you replace a crankshaft that isn't bad? Just get it miced and run the proper bearings. It'll need to be polished to size for bearing clearances even if new if you're giving them specific numbers to hit.

Link to comment
Share on other sites

The margin of error for longevity between the two options is a no brainer. You got 260k miles out of a stock OEM SB, I'd say that's pretty good.

 

You might be surprised. 260k on a cared for engine won't be as worn out as you're expecting. Typically failures are a result of gasket failures and lack of maintenance.

A resealed 260k mile engine with fresh bearings is equally as reliable as a fresh short block depending on who does the work.

 

It's a cost vs skill vs risk equation.

Link to comment
Share on other sites

350 wheel horse power? What is the ratio between wheel and crank horse power.

 

 

Probably not, I'm at 302HP as it is. If I can squeeze more out of it why not???

 

Haven't heard much from the OP lately.

 

If your still around, I suggest you follow my thread in my click here link.

 

It really is a reliable DD. That's the best way to save some money and have a fun car.

 

My dyno numbers were from a "heart breaker" Mustang Dyno. So if you want higher numbers, use some other brand of dyno.

305,600miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. (SOLD).  CHECK your oil, these cars use it.

 

Engine Build - Click Here

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


×
×
  • Create New...

Important Information

Terms of Use