myth or truth? Renix era blocks had better steel?

[omega_rugal]

what you guyes think?

[ftpiercecracker1]

Higher nickle content so the story goes, I think, no idea how such a claim could be verified. Supposedly it extends the life of the cylinder bores a fair amount.

 

But on the other hand HO blocks incorporated more webbing cast into their blocks which provided improved rigidity.

 

Which one is best? The world may never (care to) know.

[DirtyComanche]

Allegedly some of the renix blocks were thicker around the cylinders too and could be bored out farther. But IMHO it's not terribly relevant to anything.

[johnj92131]

Unimportant.  Most of us are not going to care about the block alloy.  All we want is to bore the block we have out to the next size when it is time to rebuild after 300,000 miles.

 

We are not likely to need another rebuild for another 300,000 miles, if the engine is properly rebuilt.

 

How many of us even go as far as have the blocks sonic checked for core shift?

[75sv1]

Also, it might depend on the RENIX era block. To my knowledge there were some cast in the US and some in Mexico. The ones from Mexico are suppose to be better.

[Eagle]

Allegedly some of the renix blocks were thicker around the cylinders too and could be bored out farther. But IMHO it's not terribly relevant to anything.

 

Unless you want to build a 4.7L stroker.

[Eagle]

Also, it might depend on the RENIX era block. To my knowledge there were some cast in the US and some in Mexico. The ones from Mexico are suppose to be better.

 

The proverbial VAM engines? Weren't those the older 258 c.i.d. engines?

[75sv1]

 

Also, it might depend on the RENIX era block. To my knowledge there were some cast in the US and some in Mexico. The ones from Mexico are suppose to be better.

 

The proverbial VAM engines? Weren't those the older 258 c.i.d. engines?

 

I read somewhere that it is the 4.0L. I could be wrong. Suppose to be there are the ones with a single flange rib (US??) and the double bottom flange rib (Mexico.

[johnj92131]

Allegedly some of the renix blocks were thicker around the cylinders too and could be bored out farther. But IMHO it's not terribly relevant to anything.

 

Here is a thread from Jeepstrokers that addresses which blocks can be overbored to 4 inches;

 

https://www.jeepstrokers.com/forum/viewtopic.php?f=5&t=538&p=6646&hilit=sonic+test#p6646

 

Here is the specific post I am refering to:

 

Blocks

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Postby Plechtan » December 26th, 2008, 2:53 pm

According to Lee at Hesco, the later 4.0 blocks can be bored to 4" without a problem. Well i thought i would give it a try, i had 2 blocks and here are some of the sonic test numbers 0 is the front of the cylinder, 90 is the passenger side, 180 is the rear, and 270 is drivers side. First number is is top, second is middle third is bottom. 

 

Casting 53010328AB

 

Cylinder# 0 90 180 270

1 .281 .306 .154 .291

mid .195 .315 .108 .269

bottom .814 .334 .115 .295

 

 

2 .198 .325 .180 .252

mid .182 .288 .150 . 250

bottom .189 .318 . 170 .281

 

3 .166 .342 .188 .295

mid .144 .309 . 158 .275

bottom .169 .511 .172 .305

 

4 . 188 .325 .148 .305

mid .177 .301 .136 .281

bottom .200 .388 .159 .313

 

5 .190 .327 .180 .285

mid .171 .301 .163 .254

Bottom .176 .622 .190 .280

 

6 .189 .350 .263 .280

mid .146 .321 .223 .238

bottom .182 .576 .313 .272

 

 

Casting number Casting 53010327 AB

 

1 .223 .226 .173 .261

mid .186 .236 .144 .227

Bottom .242 .268 .159 .285

 

2 .162 .284 .147 .308

mid .163 .284 .122 .244

bottom .145 .262 .201 .269

 

3 .152 .176 .185 .314

mid .133 .255 .141 .269

bottom .245 .260 .163 .274

 

4 .140 .202 .218 .360

mid .141 .202 .155 .272

bottom .169 .318 .169 .361

 

5 .161 .227 .182 .303

mid .134 .231 .155 .247

bottom .154 .261 .169 .275

 

6 .144 .225 .278 .284

mid .136 .258 .203 .242

bottom .178 .249 .231 .276

 

 

we wanted to have a .09-.10 minimum cylinder wall at the thinnest point. It looks like both castings have plenty of meat on the sides of the cylinders, but are a little thin front to back. The 328 casting is generally thicker, but has a thin spot in the center rear of the #1 cylinder. To get to 4" we have to remove about .062 per sides of the cylinder ( .125 on the diameter) We ended up using the 328 casting and sleeving the #1 cylinder, we did break through a little, but i think the sleeve has plenty of support. Both blocks had almost no wear on the cylinders, you could still see the hone marks. 

 

I will look for another 328 block to see if i can bore it to 4" without sleeving it.

Peter Lechtanski

The worlds Fastest Comanche Prroject

[omega_rugal]

Higher nickle content so the story goes, I think, no idea how such a claim could be verified. Supposedly it extends the life of the cylinder bores a fair amount.

 

But on the other hand HO blocks incorporated more webbing cast into their blocks which provided improved rigidity.

 

what if chrysler went cheap with the 4.0 after buying jeep and later the extra webbing was made to compensate the weaker blocks?

[johnj92131]

Webbing was likely part of the Noise, Vibration and harshness upgrades.  Along with the "brace" for the main bearing caps and some other changes.

 

As old tooling wears out, you replace it with new tooling and make some improvements at the same time.  The inline 6 block went thru many improvements over it's production life.

[HOrnbrod]

Webbing was likely part of the Noise, Vibration and harshness upgrades.  Along with the "brace" for the main bearing caps and some other changes.

 

Chrysler cheaping out - :yes:

 

Correct John. The 1996 factory blocks were the first to receive the extra main webs for NVH reduction, and the main bearing girdle to stiffen/strengthen the motor. I had this girdle installed in my pre-96 block by Hesco when they built my engine. Interweb pic of the girdle below:

 

 

 

These girdles can be installed on any pre 96 HO engine.

[DirtyComanche]

Chrysler cheaping out - :yes:

 

How do you explain the 0331 head?

[HOrnbrod]

:dunno:   I wasn't involved in the R&D of the 0331 head Dirty.   :yes:  I'm sure it wasn't intentional, as they lost millions developing and replacing the heads with the fixed TUPY heads.

 

They also had a similar flock up with the early V6 Pentastar heads, mainly the left side. Chrysler's not the only automotive mfg. to have massive recalls because of an aw-crap screw-up during the R&D process. Sheite happens to all vehicle manufacturers as you might realize, even to AMC. One of the reasons why they are history now.

[cruiser54]

A few years ago, I ran into a guy in my town who worked at the engine factory. He told me about the nickel content.

 

As for the VAMs, they had a 282 cubic inch that we never got. I wonder if that is the Mexican block we've heard of.

 

Don, the yellow truck had the Mexican block FWIW. 

[HOrnbrod]

Don, the yellow truck had the Mexican block FWIW. 

 

That's right - had forgotten about that. 

[big66440]

don't mean to side track the thread but the Blocks manufactured for/in Mexico could very well have better steel, if I'm not mistaken Ford actually did that with their some of their engines to withstand the high desert heat.

[omega_rugal]

don't mean to side track the thread but the Blocks manufactured for/in Mexico could very well have better steel, if I'm not mistaken Ford actually did that with their some of their engines to withstand the high desert heat.

 

the 302 blocks with the stamp of "hecho en mexico" are known to be tougher

[75sv1]

I thought Ford had problems with their blocks or heads "made in Mexico'. As for the 0331 head, I read somewhere part of the problem was that the slag did not get removed in some areas. Some they did not get annealed properly.

       I don't think I would term what Chrysler did as cheapening the block. Maybe on the HO 1st Gen. Trying to keep up with CAFE and emissions is a challenge. About the mid 90's Ford did the Duratec casting on the Duratec V-6 and the Z-Tech V-4. I want to say Cosworth did the prototyping on this process. Thinner, but stronger casting. Trying not to go to aluminum.

        Cast Iron was getting expensive during this time. Even machinery manufactures were trying to reduce cast iron in their machines. Cast iron dampens vibration. Usually a cast iron frame with a polymer or even concrete shell.