ORIGINAL: slow420a


Your exactly right, I bet that head looks like a banna, lol. If the lady that had it before you drove it around for a while with the coolent low I be that thing needs to be decked. Also the bedplate on the block will be fine. The reason the head warps is becuase its made from alunimun. The block can get lots hotter and be fine because its made out of iron where the head is a soft metal and after it gets super hot, overheating because of a lack of water, it will warp when it cools, like brake rotors.

ORIGINAL: get435

It is true that heads can warp but becuase it is an aluminium head it will most likly crack the head not warp it this is just how aluminium is steel like rotors is a totaly differant story "cast iron" heads will warp verybadly before cracking not the case with aluminium. If u susspect it of being overheated go get the head magnafluxed to make sure it is not crack they can also tell you if it is warped and if it can be milled to fix it.

ORIGINAL: slow420a


Aluminum is a softer metal than cast iron agree? If Aluminum is more ductile then cast iron then why would it crack more easily. Cast Iron is a funny thing, its very strong but brittle, so when it gets super hot it tends to crack rather then warp. Where aluminm would rather warp than crack. Its like the differance between silicone and epoxy. Epoxy is much stronger but dosent flex, the silicons is much weeker but can bend and twist.

"Call around and see how much it costs to repair (weld) cast iron. Most places can't even do it. As far as overheating either head will need to be resurfaced if overheated, that is a non issue. If anything the cast iron will crack where the aluminum will warp".

This was taken from http://www.hotrodders.com/forum/alum...s-61610-5.html

For the brake rotors, I was just using them to relate the problem with something else. Yes they are cast iron, but they are more prone to cracking. Matter factly when mine went they were warped really bad. Once I took a look at them it looked like a broken winsheild. I have a piece of rotor on my keychain that cracked off, its pretty cool.

ORIGINAL: get435
aluminium will crack rather than than warp in over heating becuse not only dose it have a lower melting temp aluminium 660°C "please note this is melting temp of pure aluminium heads may have lower melting point" cast iron 1140-1200°C than iron but that is the carcteristic of the metal itself if you have ever put a bead of weld on aluminium it dose warp faster than iron or cast iron in this cast but it warps veryfast than blows out somtimes the warp stage cannot been seen unless in slow motion the fact is 85% of the time a aluminium head will crack in averheating wther it be the little amount of metal between the cylanders ir to the outside of the block they are notorious for it prime ex. i had a 1984 ford bronco II had cast iron block and head over heated by previous owner and heads warped almost beyone repair my grandfathers cavalier cast iron block aluminium head same thing and it cracked his head between ever cylander call any macinest u want and they will tell ya as well most aluminium head will crack becuase of overheating.

ORIGINAL: vertigo14k

I thought in just getting a new motor. I'm getting my income tax return of $5 G's I wanna go for a 4g63T AWD, what are the difficulties for getting this to be put on. If its too complicated where would be the best place or website for getting a 4g63t engine and tranny at a low price.