OEM 7m forged internals?

[Bluechulappa]

Sorry if this has been asked. I searched two forums and google and couldn't find a true answer. I just want to know if the 7m has OEM factory forged internals or not? I've been told it does but I have not been provided with an evidence other than word of mouth.

I'm doing an OEM rebuild with new parts. To me, this question isn't going to change anything that I'm doing in my rebuild. It's already been proven that a properly built oem 7m can handle good power. Just thought it would be a fun fact to know!

 

[dumbo]

Turbo A's i think...

 

[Bluechulappa]

I was thinking they do NOT come with oem forged internals since ppl always say they are buying FORGED pistons and such. But I do realize there are other purposes for buying these aftermarket parts such as bore size and weight...

 

[IJ.]

Rods and Crank are forged pistons are Cast

 

[Doward]

Yep, and to expound - the same holds true on the JZ engines, but the pistons are hypereutectic.

 

[IJ.]

Still cast

 

[dumbo]

wow sorry to post that then..where did i hear that

 

[zurud]

If stock rod is forged, why people upgrade the rod to eagle?

 

[IJ.]

What do you mean "if"......

maybe 20 years of fatigue and advances in metallurgy and design.

 

[starscream5000]

^ That could be it...... Nah!

 

[Bluechulappa]

Good information! So rods and crank are forged...

Is this common on engines back then or even today?

 

[starscream5000]

Not as common back then, but it's common on performance cars nowadays, almost mandatory.

For the price the supra sold for, even back then, there better have been some damned forged internals in it!

 

[figgie]

Well think about it this way.

Back in 1987 a 91mm stroke car was redlinedwith 6500 rpm.

Every other engine of that time save forthe smaller I-4 where in the mid 5k RPM for redline (see every single GM, Ford, Mazda 6 cylinder engine). The Supra had to have forged internal back then. )

 

[landspeedrich]

Back in early 90's.Fords SHO V-6 (I had one) with Yamaha heads had a red line of 7000,and in reality would run up to 9000 rpms without a problem.Only thing the accessories like alt,PS,A/C tend to not be able take the higher rpms kindly.So the factory set RL at 7000.
There also different grades or levels of forging that factories use as oppose to what a Crower ,Lunati use for a true race crank.The heatreating type will determine also how good of a crank you might have,and whether or not it would need to be re heatreated after machining.
I believe the stock Supra internals are good for up to 500 hp or so.Depending on where or how much you might be beating on it? Later RS

 

[Frank Rizzo]

Taurus SHO debuted in 1989, had an 80mm stroke and redlined at 7300rpm.

 

[figgie]

lol.

nearly 11mm smaller stroke! And technically the SHO was a japanese engine as Yamaha played a huge part in its development.

Now a days you have 91+mm stroke motors running 7000 rpm redline without one hiccup. That is 15 years after the fact though

 

[adampecush]

If stock rod is forged, why people upgrade the rod to eagle?

because forging is merely a manufacturing process, not the be-all and end-all of materials.