How would you know if you need to bore your engine?

[Cassera]

I am planing on building a 1g eclipse gsx and I want to do everything right the first time. I know that boring the engine to (.02 over) wont really add performance realistically, but I want to do things right the first time and make sure I have a clean straight piston cycle since these cars are almost 20 years old.

Now my question to you guys is how would you know if you need to get it bored to have tight sealing pistons.

(Chances are I will remove the engine to do some internals and get it stroked anyway)

I appriciate your wisdom and time A LOT so thank you for any responses.

 

[johnboy1065]

How many miles are on the engine?
can you still see the cross stitching on the cylinder walls?

Once I had the head off of my evo. I had a machine shop owner come out to look at it. He used a cylinder bore gauge to test if the cylinder was straight or not.

Also, rub your fingernail along the cylinder walls. If your nail gets caught on anything then you probably need to at least hone it.


Also, if you don't feel like pulling the head. A simple compression test or leakdown test will give you at least some idea on the health of your engine.

 

[Cassera]

Thanks a lot...I never would have thought of a compression test just to see overall engine health. I currently do not have the car but I will be getting it in the next couple of months. I am trying to do all my research so I am ready for when I get it. Chances are it will have over 130k miles on it
I definately will be doing a lot of maintenence on it and run a lot of tests to see if the engine is in good condition to do work to it.

What tests would you reccomend I run on a 130+k mile engine besides the compression test?

 

[FactoryChrome]

If you can feel anything with your fingernail in the cyl bore then you're going to need more than just a hone.

 

[hhuricane]

The only way to know if it needs a bore job is to measure the cylinders with a bore gauge. Take the block to a machine shop and have them measure it for you.

 

[FLASH1970]

To check your cylinder "roundness" you need a bore gauge. It's not hard to do. I'm sure there is a video on youtube about doing it. Get a Haynes manual or a factory service manual and check what tolerances are acceptable. If you do have to hone it, take it to a machine shop and do it right. The hone job done with a power drill and a 20 dollar honer from e-bay will do more bad than good.

Before you tear the engine apart, do a compression test. If the compression test results aren't the greatest, I would do a leakdown test to see why the numbers aren't adding up. If the compression test is good, I would focus on maintenance. You'll want to do maintenance like a timing belt, spark plugs, wires, flush the fluids. While you have the timing belt off, check the oil pump for excessive play.

What are your power goals for the car? Based on how far you want to take it, you might not have to tear the engine apart if it's healthy.

 

[Cassera]

Well I dont really have a power goal. I just have a setup I want to go with. I am thinking about stroking it to a 2.3 and upping the compression to 8:5:1

I want to do all fuel mods such as 255fp, Afpr, maybe 850 injectors or bigger, fuel rail.
Than I want to get a boost controler (obviouslly) and some headstuds so I can hold high boost. Along with that I will also need a DSM Link.

Than I will look into some turbos such as an FP Green or Garrett GT3076R. I am aiming for 25-28lbs of boost on pump gas (93 obviouslly)
After that I will be looking at intake manifolds and cams (w/ springs and retainers) so I can get some great topend along with the turbo.

Which one of those turbos would you reccomend for that setup? Or do you think they would be a bit too small for a stroker? I dont mind a little lag because I figure the stroker will makeup for the bottom end power.

 

[FLASH1970]

You'll want bigger injectors if you want to fully take advantage of turbos that big. You ahould have a power goal and a purpose for the car before you start spending money on parts. If you just start throwing money at big name popular parts and mods, you might end up spending a lot more and have a setup that isn't as good as someone who planned out what they wanted to use the car for.

 

[Cassera]

You'll want bigger injectors if you want to fully take advantage of turbos that big. You ahould have a power goal and a purpose for the car before you start spending money on parts. If you just start throwing money at big name popular parts and mods, you might end up spending a lot more and have a setup that isn't as good as someone who planned out what they wanted to use the car for.

Yeah I do agree with that %100. The thing is I try not to have a power goal because when you do hit that power goal, your always going to want more which can cause you to replace some parts you already spent money on.​

I'm doing A LOT of research to see what would be best with the setup I want. It seems as I am coming along just fine. Im trying to get a parts list going that will have me set for around 280-300whp but have room for more power such as a fully upgraded fuel system.​

It will be a slow process, especially since I intend to have the engine machiened as much as possible before I start working on it.
I just want to do things right the first time around, even if it does cost a lot of money it will all be gradual so it will give me time to reconsider some parts.​

 

[FactoryChrome]

The only way to know if it needs a bore job is to measure the cylinders with a bore gauge. Take the block to a machine shop and have them measure it for you.

Seriously?.... if you can feel scratches in the cylinder with your fingernail the block WILL NEED to be bored... forget the gauge... forget the machine shop inspection.... or you can do it the "tuners" way and just hone a gouged cylinder bore put new rings in it and get some nice shiny new compression issues.