A sweet Read

[elscotto80]

Found this, very interesting read, puts a lot of facts in place and gets rid of some myths.

http://mazda4club.forumsplace.com/message-20.html

[Lex]

Great read indeed! The link will be added to the sticky "Turbo Information" information

[D323]

stuck for ya. That is a good find.

[BuGS]

GTR Rods are fordged.....

[D323]

GTR Rods are fordged.....

no, they are squeeze cast. You can see from the picture on the link above the casting marks on the side of the rod.

This was discussed at length a while back.

http://www.wihandyman.com/forum/showthread.php?t=18365&highlight=GTR+rods

[Lex]

I have always wondered about that ... are the GTX rods squeeze cast as well - or are they just normall cast?

no, they are squeeze cast. You can see from the picture on the link above the casting marks on the side of the rod.

This was discussed at length a while back.
http://www.wihandyman.com/forum/show...light=GTR+rods

[D323]

no, notice in the pic that BPT323 posted in link I gave shows the rough surface? That is from the sand in the regular casting process.

GTX < B6t < GTR

the B6t rods are just regular cast as well, but are a bit beefier than the GTX rods. They do however have a small problem with cracking when pushed.

[elscotto80]

I also like how it puts the so called "web stiffened" block to rest aswell.

[Silentbob343]

I have read that the BP N/A intake was better than the GTX intake. Looking at the GTR intake you notice some obstructions that,

It was Mazda's finding that with more a more commonly used equal-length intake manifold, the tract nearest to the air entry received the least volume/pressure, and the farthest tract the most. By trial, measurement and testing, the engine team perfected a cast aluminum manifold that has intricately curved and sized "walls" between the individual tracts leading to the intake ports to equalize air volume and pressure. A bonus is that the manifold's swirl generating effect contribute to efficient combustion. The equalizer intake manifolds have shown its effectiveness in improving torque from idling to the Group-A 300-bhp-plus output level and all the way up to maximum revs.

So perhaps the N/A BP intake isn't better than the GTX?

Next question; besides the sodium filled exhaust valves is there any diffrences between the GTX and GTR heads, i.e. larger ports, different cams, etc? Again I believe I read that people were choosing the N/A BP head versus the GTX heads.

[D323]

I have read that the BP N/A intake was better than the GTX intake. Looking at the GTR intake you notice some obstructions that,

So perhaps the N/A BP intake isn't better than the GTX?

Next question; besides the sodium filled exhaust valves is there any diffrences between the GTX and GTR heads, i.e. larger ports, different cams, etc? Again I believe I read that people were choosing the N/A BP head versus the GTX heads.

you are correct to mention that people have posted about swapping the NA heads out on here for the better flow. After reading that, I will probably keep my GTX head, and just have it cleaned up with some port and valve work.

The person to ask would be James (limpgtx) as he was making 330whp or something like that, and he was in the process of an NA head swap when he last posted. I'd be curious to see if he has finished and gone down in power, or increased any at all.

[Silentbob343]

Yeah, it seems to me many assume that larger equals better with out looking at the entire picture. Perhaps some things were designed to work better in conjuction with certain other parts.

I hope james does tell us his findings.

[BuGS]

no, they are squeeze cast. You can see from the picture on the link above the casting marks on the side of the rod.

This was discussed at length a while back.
http://www.wihandyman.com/forum/show...light=GTR+rods

Ok, I guess that makes sense.

BTW for those who don't know what Squeeze casting is:

Squeeze casting, also known as liquid metal forging, is a combination of casting and forging process.

The molten metal is poured into the bottom half of the pre-heated die. As the metal starts solidifying, the upper half closes the die and applies pressure during the solidification process. The amount of pressure thus applied is significantly less than used in forging, and parts of great detail can be produced. Coring can be used with this process to form holes and recesses. The porosity is low and the mechanical properties are improved.

Both ferrous and non-ferrous materials can be produced using this method.

[Lex]

It would be great to have access to a cheap dyno and test the before and after effects of changing single variables - like just the head or just the intake manifold etc.

[Silentbob343]

yeah it would.....

but does anybody know, besides the sodium filled valves, the differences between GTX/GTR/NA-BP heads, i.e. ports sizes, cams, etc?

[Marc93lx]

Those are some sweet comparo shots of the vj23 vs. the vj20.....seem's like I've seen them before. lol