Hmmm: 1GR-FE impossible to bore the block?

Just reading up on the 4.0, and noticed that you can't re-bore the block... So these blocks are throw away? Unbelievable - they don't make 'em like they use to (22-RE, 3VZ...)

Check it out:

"This engine has special cast-iron cylinder liners cast into the block, which are a spiny type to improve adhesion between the liner and cylinder block. With these special thin liners it is impossible to bore the block."

hxxp://en.wikipedia.org/wiki/Toyota_GR_engine

 

Why does that make them "throw away"?

 

No idea... I had a 22-RE in my 87 4-Runner and the guy at the shop said they could be bored up-to 50 over... You could literally rebuild those blocks twice easy...

I hope someone here is knowledgeable enough to educate me as to why these blocks are impossible to bore...

 

Nothing's impossible with enough time and money.

"Much harder" to bore the block would be a more appropriate term.

 

its also wikipedia that your getting your info. maybe go to a more reliable source to get your info.

 

Sure thing any recommendations?

 

let me do a little searching and see if i can find some useful info before chris pops his head in this thread lol

 

With motorcycles, the liners themselves aren't borable, but they can be removed and thinner liners pressed in. However, if they are "cast" into the block, the liners may not be removable.

 

i tried multiple things in a google search and basically the only thing is the first couple links that go to wiki. maybe there is a member on here that will chime in soon and has come across this dilemma

 

Figured this one would be a good topic. I can't find anything to the contrary so far...

 

if you bore the liners out even further they can crack and you have a bigger issue with hotspots because there isn't as much material to soak up the heat

 

ya i do apologize! I reread my post and it seemed very harsh and unlike what I intended it as. It is a great topic which i dont think I have seen before and now we all know what the deal is!

 

Hey no sweat; didn't take it as such.

 

A big boo boo, like run the engine for 300 thousand Kms? That's what I had on my 4Runner before I decided to give it some more life - motor was tired... I plan on running this one just as long - had the other one 21 years before buying this Taco.

 

Makes sense. I just think their was better wording than "throw away"

 

Glad to hear that for sure - Like I said though, I didn't have a major malfunction with my 22-RE, it was tired though... I only had to bore it 20 over, and now have over 560 thousand KM on the truck... As I eluded to before, my machine shop indicated that it had enough meat on it for up-to 50 over. Hence, I could have bored it again (if needed).

That's my only point; in terms of reliability I have no doubt Toyota still has it (that's why I purchased this 2010).