Mopar 383 Connecting Rods

[Larry Hill]

It looks like mine

[Tom Broome]

Larry, that looks like the AG 300 I learned on. We were taught to check the bore against the faceplate, then pull the rod away while holding it steady against the fixed upper point, then gently rock the rod. We would do that at a couple of points, flip the rod over and check the other side. That would allow us to check for barrel or taper. Sunnen used to lease a PG series gauge with a faceplate that slid in and out to check taper or barrel. Even if I could afford one, it would be probably be to finicky for my little un-airconditioned shop.

[Tom Broome]

Back to the original post. It's difficult to qualify OEM mass production rods. Small variations in bolt centerline between the rod and cap, how perpendicular the bolt (or nut) spotface is to the bolt centerline affect the repeatability when the bolt is torqued.

Back in the Buick days we would deburr a small spot inside the "H" beam of a Carrillo rod, just above the bolt thread exit. It's been too long to recall the specifics, but I remember it was significant enough to resize the big end. That's when I began to understand how touchy rods can be, and how important it is to maintain consistency between preparation and assembly.

The shop procedure was to hone the big ends individually since the rods run on split journals. It required a lot of attention to keep the stones and guide shoes from wearing in a fashion that caused barrel shaped housing bores.

[Rich Biebel]

I did most every rod in a small shop for over 10 years.

All brands and from street rebuilds to race engines of all kinds.

Sunnen manual LBB machine with the gauge.

Did big ends, small ends, bushed rods, offset bushed and reduced pin sizes using bushings we made or bought.

Stock rods used in race engines were generally out of round once run....

Usually a good amount....

We used SPS bolts back then and picked the best looking cores we could find.....Did not matter once it was run....out of round...

Mag, shotpeen, resize, bush pin end....generally

Very difficult to hone big ends or even pin ends and hold them true and without a taper one way or the other....

I would chuck the mandrels up in a lathe and true up the brass guide shoes often and dress the stones....constantly...

I used the gauge to check the rod and as described held it flat and carefully pulled it away from the back reading the size. A very tedious process......honing to size and keeping them as straight as possible....

I always honed rods and let them sit and they change size as the honing process heats them up.....let 'em cool and touch 'em up....

A buddy had a shop with a similar machine but with a power stroker and I don't know if that helped as I think it did pairs of rods at one time...

Honing anything was a time consuming process if you were trying to do as good as possible....

I marvel at the Youtube videos of Block hones that do a V8 without an operator constantly running the machine and checking the bore sizes....

Honing a race block and doing a real good job was the shop owners specialty along with head work.....Any block he honed made better power than previously usually....



I also rebuilt Mack connecting rods a lot......new bushings mostly....big ends were usually pretty good even after a half million miles ! Engines in UPS trucks....

[Paul Precht]

Originally Posted by Rich Biebel

I did most every rod in a small shop for over 10 years.

All brands and from street rebuilds to race engines of all kinds.

Sunnen manual LBB machine with the gauge.

Did big ends, small ends, bushed rods, offset bushed and reduced pin sizes using bushings we made or bought.

Stock rods used in race engines were generally out of round once run....

Usually a good amount....

We used SPS bolts back then and picked the best looking cores we could find.....Did not matter once it was run....out of round...

Mag, shotpeen, resize, bush pin end....generally

Very difficult to hone big ends or even pin ends and hold them true and without a taper one way or the other....

I would chuck the mandrels up in a lathe and true up the brass guide shoes often and dress the stones....constantly...

I used the gauge to check the rod and as described held it flat and carefully pulled it away from the back reading the size. A very tedious process......honing to size and keeping them as straight as possible....

I always honed rods and let them sit and they change size as the honing process heats them up.....let 'em cool and touch 'em up....

A buddy had a shop with a similar machine but with a power stroker and I don't know if that helped as I think it did pairs of rods at one time...

Honing anything was a time consuming process if you were trying to do as good as possible....

I marvel at the Youtube videos of Block hones that do a V8 without an operator constantly running the machine and checking the bore sizes....

Honing a race block and doing a real good job was the shop owners specialty along with head work.....Any block he honed made better power than previously usually....



I also rebuilt Mack connecting rods a lot......new bushings mostly....big ends were usually pretty good even after a half million miles ! Engines in UPS trucks....

I have a nice LBB-1499 with the AG, not sure when they were made but I'm thinking 60s. I did hundreds of rods on an old bench top Sunnen in a shop I used to work at, not sure what model it was. It's an art that definitely takes time and talent to master.

[Larry Hill]

''It's an art that definitely takes time and talent to master.'' How true!

[Tom Broome]

Originally Posted by Larry Hill

''It's an art that definitely takes time and talent to master.'' How true!

Kinda' like block honing.

[Larry Hill]

Any size target honing is the artform, "damn I honed to much wont fix it".

[Rich Biebel]

Ya can’t put metal back so ya gotta sneak up on it !

[HP HUNTER]

Originally Posted by Rich Biebel

I did most every rod in a small shop for over 10 years.

All brands and from street rebuilds to race engines of all kinds.

Sunnen manual LBB machine with the gauge.

Did big ends, small ends, bushed rods, offset bushed and reduced pin sizes using bushings we made or bought.

Stock rods used in race engines were generally out of round once run....

Usually a good amount....

We used SPS bolts back then and picked the best looking cores we could find.....Did not matter once it was run....out of round...

Mag, shotpeen, resize, bush pin end....generally

Very difficult to hone big ends or even pin ends and hold them true and without a taper one way or the other....

I would chuck the mandrels up in a lathe and true up the brass guide shoes often and dress the stones....constantly...

I used the gauge to check the rod and as described held it flat and carefully pulled it away from the back reading the size. A very tedious process......honing to size and keeping them as straight as possible....

I always honed rods and let them sit and they change size as the honing process heats them up.....let 'em cool and touch 'em up....

A buddy had a shop with a similar machine but with a power stroker and I don't know if that helped as I think it did pairs of rods at one time...

Honing anything was a time consuming process if you were trying to do as good as possible....

I marvel at the Youtube videos of Block hones that do a V8 without an operator constantly running the machine and checking the bore sizes....

Honing a race block and doing a real good job was the shop owners specialty along with head work.....Any block he honed made better power than previously usually....



I also rebuilt Mack connecting rods a lot......new bushings mostly....big ends were usually pretty good even after a half million miles ! Engines in UPS trucks....

You have two rods your honing..........theres .0025 to hone to size on both rods, one rod has .0005 taper the other has .0007 taper. How do you set these two rods up on the already trued mandrel?