TIII billet aluminum mechanical rockers being tested.

[Directconnection]

When you think about it... cast aluminum rocker with pressed components might not be the best after lots of years and run time vs the steel rockers of the 8v. Snap ring ends on the pins would have been so much better, but thank you penny pinchers at Chrysler... this was the far more cost effective procedure.

[GLHNSLHT2]

who designed the rockers? Chryco or lotus. Cast aluminum is probably lighter than stamped steel and the T3 head has enough reciprocating mass as it is. I'd thing stamped steel rockers are probably cheaper to make too.

[turbovanman²]

When you think about it... cast aluminum rocker with pressed components might not be the best after lots of years and run time vs the steel rockers of the 8v. Snap ring ends on the pins would have been so much better, but thank you penny pinchers at Chrysler... this was the far more cost effective procedure.

Many cars use this type of setup with no issues, so its not really a penny pinching issue,

[Directconnection]

who designed the rockers? Chryco or lotus. Cast aluminum is probably lighter than stamped steel and the T3 head has enough reciprocating mass as it is. I'd thing stamped steel rockers are probably cheaper to make too.

Exactly. Too much mass if made of steel. They are made by INA.

I was fortunate enough last year to talk to the chief engineer of the T-III head. He told me about a roundtable meeting they had after they got the green light to start the design of a dohc 16v head for the 2.2. It was he (representing Chrysler) a representative from Lotus, and another from INA (fwiw: INA has their logo on these rockers) I forgot who wanted what, but neither could agree on the type of valvetrain they wanted. I believe Chrysler wanted the bucket/shim style..... but hood clearance would pose an issue, hence why the T-III has the cams kinda spread apart and rockers actuating on the sides of the cams vs. on top. I believe it was INA that won out....

---------- Post added at 07:23 PM ---------- Previous post was at 07:22 PM ----------

Many cars use this type of setup with no issues, so its not really a penny pinching issue,

It is a penny pinching issue to not use c-clips which cost additionally, plus the labor of installing them vs one machine in one operation that peens the ends. Sadly, they didn't "peen" them well enough on some.

[Reaper1]

Cam on bucket worked in the Masi....hmmm....

[Directconnection]

Cam on bucket worked in the Masi....hmmm....

I know... but the masi head wasn't intended to be installed originally in the L-bodies, even though they do fit rather well I am told.

[GLHNSLHT2]

was the T3 originally intended for Lbodies? Now I've got to go measure the height of my Masi head vs an 8v head next time I'm at the shop.

[Reaper1]

I thought the TIII was intended for P-bodies, then adapted to the G, J, and A bodies?

[turbovanman²]

Exactly. Too much mass if made of steel. They are made by INA.

I was fortunate enough last year to talk to the chief engineer of the T-III head. He told me about a roundtable meeting they had after they got the green light to start the design of a dohc 16v head for the 2.2. It was he (representing Chrysler) a representative from Lotus, and another from INA (fwiw: INA has their logo on these rockers) I forgot who wanted what, but neither could agree on the type of valvetrain they wanted. I believe Chrysler wanted the bucket/shim style..... but hood clearance would pose an issue, hence why the T-III has the cams kinda spread apart and rockers actuating on the sides of the cams vs. on top. I believe it was INA that won out....

---------- Post added at 07:23 PM ---------- Previous post was at 07:22 PM ----------



It is a penny pinching issue to not use c-clips which cost additionally, plus the labor of installing them vs one machine in one operation that peens the ends. Sadly, they didn't "peen" them well enough on some.

I love the story's on these engines, makes me wonder how they even run,

I can't count on one finger on any OE engine that has c clips on their factory rockers.

I know... but the masi head wasn't intended to be installed originally in the L-bodies, even though they do fit rather well I am told.

I can't see them thinking about L body's, hell, they were in the process of killing it off, plus it doesn't really fit without some mods.

was the T3 originally intended for Lbodies? Now I've got to go measure the height of my Masi head vs an 8v head next time I'm at the shop.

Like I said, I find that extremely hard to find.

[Directconnection]

was the T3 originally intended for Lbodies? Now I've got to go measure the height of my Masi head vs an 8v head next time I'm at the shop.

I am pretty sure you'll have no issues.

I thought the TIII was intended for P-bodies, then adapted to the G, J, and A bodies?

It was (and also the Daytona) but, being that the program (T-III) was started on March 1st of 1985, I doubt they were thinking 2 years ahead to install it in the P-body at the time (but I could be wrong... maybe the P-body was just on paper or they had a few test mules at the time)

---------- Post added at 05:37 PM ---------- Previous post was at 05:29 PM ----------

I love the story's on these engines, makes me wonder how they even run,

I can't count on one finger on any OE engine that has c clips on their factory rockers.

I got one finger you can count on! Anyways, why do you read so deeply into people's emails as of late? (ie: Shadow, Carroll, etc...) Of course there are no production roller's with c-clips,(that I am aware of) you answered your own question. More assembly procedures, and parts = pennies that add up to dollars. In which, Simon has more Dollars than Sense

I can't see them thinking about L body's, hell, they were in the process of killing it off, plus it doesn't really fit without some mods. Like I said, I find that extremely hard to find.

I've seen a few L-bodies with T-III's... never heard/noticed that they required any trick mods to shoe-horn them in there.... other than shoe-horning them in there.

[rich tideswell]

In my opinion, aluminum is not a good choice for a moving part such as a rocker arm. Even billet aluminum is only slightly better. It has everything to do with aluminum's metallic properties, every time it's stressed (even if it's not stressed to it's limit), it's one step closer to breakage, where as steel is won't break so long as it's not stressed passed it's breakage limit. I know the argument "aluminum is better because it's lighter, and lighter is better". Generally i agree, BUT so long as the rocker arm is balanced on the shaft, the extra mass won't be noticeable.

If i were to develop a new rocker arm for the TIII, I would use tool steel - most likely cnc machine because it would be easier/ cheaper to crank them out in small batches versus casting or stamping. I would pattern mine after something like this http://www.compcams.com/Products/CC-...kers%27-0.aspx

[turbovanman²]

I got one finger you can count on! Anyways, why do you read so deeply into people's emails as of late? (ie: Shadow, Carroll, etc...) Of course there are no production roller's with c-clips,(that I am aware of) you answered your own question. More assembly procedures, and parts = pennies that add up to dollars. In which, Simon has more Dollars than Sense



I've seen a few L-bodies with T-III's... never heard/noticed that they required any trick mods to shoe-horn them in there.... other than shoe-horning them in there.

You said they should have put c-clips on, well durrr, that's a no brainer but in real world land, that's too costly, so agreeing with you partly. Carroll? One thread with Shadow? I can count on one hand your thread arguments,

To fit an L body, the frame has to be notched, the intake modified or rad mods-not sure if people do that because or because the intake is so close or actually touch's the rad, and not sure if a/c would be make to work.

[Directconnection]

Simon, you are being a meatstick.

Never heard of notching the frame, though... the guy I met that had it done years ago never mentioned this at all. (GLH-T)

---------- Post added at 05:57 PM ---------- Previous post was at 05:51 PM ----------

In my opinion, aluminum is not a good choice for a moving part such as a rocker arm.

If the INA, being a light casting, has held up without issue (other than the press issue on the pins) than a billet aluminum would be way stronger. 6061 is the common stuff.... but if I were Wallace, I'd go with what we used to use for making molds in the machine shop (very hard, dense, and tough for aluminum) It's called T7 (7050?) something... stuff costs more, but is soooooooo much better than the generic aluminum used in millions of CNC machined products these days.

[Reaper1]

While I agree that aluminum WILL tool harden and fail over a certain amount of cycles, I think in this case we are talking BILLIONS of cycles. Pretty much more than the lifespan of almost ANY TIII engine, even being wrung out to the max. In this case I don't think it's the aluminum so much as we're seeing a design flaw. Either the pin should be retained better, there should be better lubrication to the bearing, or the aluminum should be a higher heat treatment, or a different alloy (or both).

[GLHNSLHT2]

I am pretty sure you'll have no issues.

I'm not worried about the height to get it into an Lbody. I'm just curious because you stated they didn't want to do bucket/shim because of the height on a T3. So I want to know if my Masi Bucket/shim is taller than my 8v.

[135sohc]

It was (and also the Daytona) but, being that the program (T-III) was started on March 1st of 1985, I doubt they were thinking 2 years ahead to install it in the P-body at the time (but I could be wrong... maybe the P-body was just on paper or they had a few test mules at the time)

The P body was intended to be released in 85.

[Lotashelbys]

All I can say is make them out of 7075............

[Directconnection]

All I can say is make them out of 7075............

Yes, 7075 is what I was trying to think of.... I knew there was a 7.. a 0... and a 5.... hehehe

[zin]

Great material, we make a lot of our stuff from it, pretty much the same strength of mild steel, but it needs to be hard anodized due to some of the alloying agents in it to ensure it doesn't develop issues (years) down the line.

Mike

[Lotashelbys]

Great material, we make a lot of our stuff from it, pretty much the same strength of mild steel, but it needs to be hard anodized due to some of the alloying agents in it to ensure it doesn't develop issues (years) down the line.

Mike

Thats just about exactly what I was gonna say if someone asked why 7075. Hard anodizing would really make a nice surface for them to ride on the shaft. The last part we had made from it has lasted so long and is so strong compared to the 6061 they were made out before I really just cant believe the difference.