Thread: Bluebird disassembled, question

So I'm rebuilding a bluebird for a "customer"/friend. Said it had low compression when pulled, he want's to swap out his JDM engine and drop this in and go turbo hoping for 250+ whp. Well, this is what I found:









There are almost no hash marks in the cyl on the first two pictures. Would you just hone this block or have it bored, new pistons, balanced, ect....

I personally think it's to gone to hone and recommend having it bored and all that fun stuff.









Few other pics, the VC was siliconed on

When I pulled the oil pan I found an extra slotted shim in it and it looked like one of the rockers had been replaced by a junkyard part so I'm guessing they over revved it and lost the rocker arm at some point.

(top cam, second rocker arm from the chain, you can barely see it, but it's darker than all the rest)

Are those cylinder wall pics of the engine with low compression?
Honestly, I like to see minimal cross hatching when I tear down an engine. To me that means the rings have sealed properly against the wall and someone broke the engine in properly (a rarity from your average Joe).

hone it and go, someone's def. been in there though. Check the tolerances on the cylinders and rings while you got it apart. Is the crosshatching still there on the entire cylinder or more so on two sides etc.?

I don't know, I was told it had low compression when the engine was pulled. I personally never saw the engine run. The vehicle this was in was bought as a parts car so I don't think it ever ran nor was a compression test ever preformed.

I have another SR apart right now that I'm building for my car, when I pulled it apart there was no wear at all like this on my particular engine so I was able to just hone mine and drop in my new pistons and rings.

When I do engines at the dealer I'm at and they have wear similar to this we put a new short block in it because toyota won't let you hone them under warranty.

What do you think was the cause of the low compression?

low compression isn't always rings either...keep that in mind. You said something was up with the valvetrain? All valves sealing properly?

Did the plugs give any hint which cylinder might be the issue? As mentioned above and due to the shims being found, it sounds like this had a history of some type of bad shifting.

Before I even received the engine I was guessing rings, but since I opened it up I was thinking it could be something along the lines of a combo of rings, valvetrain issues.



I haven't checked the head yet, I'm taking it to work tomorrow to check it. It appears they threw a rocker arm at some point in time, I do not know if it was before or after the low compression developed.

The story I got with the engine was it was put in a 92 SE-R, it developed low compression and he sold the car to a kid who ragged the hell out of the car. After he beat the hell out of it he sold it for parts, the engine was removed and put in storage until now.

bore it and call it a day

Hone it, boring is not needed there.