Torque plates for honing blocks

[Gremlin4ever]

I've been calling and visiting area (Atlanta & metro) machine shops for a AMC torque plate so I can start the machining proccess of my 401. Noone (so far) has one, but I did get the name of a company thats produces them, PHJ, but I can't seem to find their web sight.

Even though I'm not building a "high HP" engine (this time), I would like to blueprint and build it as durable as I can. Any info on ways of aquiring a torque plate for an AMC 401 would be much appreciated :sa:

[jeepsr4ever]

I am not sure how much they would cost but since we have the head gaskets on CAD we could make torque blocks but right now we would need 3 weeks leadtime and they might come in at $220...hmmm you should try to pm holeshot, he may deal with those...dunno

[Gremlin4ever]

Been searching around on the Hot Rod Magazine web site for old articles on honing with torque plates. What I found was BHJ not PHJ (LOL). Misunderstanding on my part (my hearing deficiency) thought they said "P". Anyway, for a "racer net" of $348+ one can be had for the AMC V8. Inline 6 are available as well, thats BHJinc.com for those interested.

I also saw a "head torque plate" that bolts to the head for valve seat grinding. Never heard of that, but it says it has great advantages as the valve seat distorts when torqued to the block.

Man, the technology just never stops :!:

[Lifted79CJ7]

So Gremlin, what is a torque plate? Sounds like something used to line the tools up to hone the block??? Just wondering and would like to learn a little today.... :wink:
Jack

[jeepsr4ever]

Jack basically a torque plate is used in very high performance engine building where the torque of the heads and stress on the block are simulated before boring and honing by way of a large steel plate that is torqued down to the block. I am neutral on the subject as I havent seen any gains from this and when you take the plates off the casting tweaks and when you put the heads on it tweaks again. Maybe for a 12000rpm motor you would see the difference but I havent hit over 9000rpm with any AMC V8

[Lifted79CJ7]

Ahhh, OK. It makes sense, but like you said, I think this would really only be necessary in highly stress situations (race engines like you said). On a side note, what was the best AMC engine you think you've ever put together??? :-|
Jack

[Gremlin4ever]

Facts are facts and the fact is (haha) that the cylinders are out of round once the head is torqued down if bored and honed without the plate. This and other small "hurdles" one incounters in rebuilding an engine may not be noticed in "horse power" gains at low RPMs, but will help out massively in durability in the life of an engine. Since I love AMC power and the rides that it comes in as well as the fact (haha) the you just can't get them at you local dealer anymore tends to make "me" want to build them as best I can 111!!!

I want my AMC engines to last longer than factory, so I will assemble it many times during the rebuild process to make sure I get the durability I seek :wink:

Now don't take all that the wrong way for I'm just an Aries (stubborn perfectionist), I can't help it :roll:

[jeepsr4ever]

Your right

[Lifted79CJ7]

Shoo, feel free to come over and throw this old dog a bone when I actually get the funds up to finish my engine! Man, my dumb arse is all about instant gratification!! :lo1l:
Jack (needs to learn a little more patience at apying attention to details on engines) #-o

[Gremlin4ever]

Pontiac was the only Automaker to use them in production. It is not just for hiperformance issues as torquing on any style engine you're building alters it's shape. Aren't we looking for a good "ring seal" in the end of any rebuild?

[Mudrat]

What are these made of??? 1" hi-tensile steel or something or full thickness (like a head) casting that has the appropriate bore???

Curious - educate me too!!

Pat

[Gremlin4ever]

Never held one, but guessing I'de say at least 2" thick and it has to be rigid enough to not warp when torqued down (Steel maybe?). The bore should be greater than the block so the boreing tools can still be used on the block.

[tarior]

It's funny that this subject comes up, I was just talking to my favorite machinist the other day about torque plates. It seems that the torque plate is made of the same material as the head that is suimulates. So, for iron heads one would use a cast iron torque plate, for aluminum heads, you would want an aluminum torque plate. :-|

[fuzz401]

they are about 1.5 to 2 " thick with the head bolt holes counter sunk so they do not interfear with the boring or honing made out of cast steel/iron
I borried one when I did my 401 :?
I have hears of taking a old head and cuttint it in half to make one too

[Rogue Racer]

"the technology never ends" . . . How true, how true.

There are and have been several developments in the torque plate product arena. There are plates that have the retaining bolt holes countersunk to not interfere with a boring bar when it is mounted on the top of the block surface. There are also plates with cuts for some bolts and stands or spacers for others so that stock head bolts can be used to closer simulate the stretching effect on the block when a head is bolted on. Such plates are used for honing or can be used with a Rottler or other type of boring machine that jigs off the crankshaft centerline and has a floating head that is not attached to the block. There are aluminum plates to simulate the stress an aluminum head on the block. There are some professional race engine builders who circulate hot water through the block and bolt on motor mounts, bellhousing and a head on the side of the block not being honed to more closely simulate operating conditions.

The purpose of all the efforts is to acheive cylinders that are as round and straight as possible. The same reason race blocks are filled in the water jackets with epoxies and concrete materials. Some factors are unknowns, such as block distortion due to torque and the effect of the crank assembly swinging on the inside of the case at a gazillion RPM, but the principle of round and straight cylinders has been proven to be advantageous in the racing arena and in production engines. The torque plates have been an important factor in the technology to acheive that end. How much is necessary and what really works? Lots of debate on those questions. From my experience, the AMC block is not as distorted when the heads are bolted on as most Detroit V8s from the 60s and 70s.

A little test for those of you who get into such stuff is to use a quality dial bore gauge (or maybe a good inside micrometer if you have the skill) to measure the cylinder bore at several points around the cylinder within the top inch of the block. Record your readings. Then bolt a head on the block using a head gasket and torque specs just like you would if you were assembling the engine. The turn the block over and measure the same cylinder in the same places reaching in from the bottom of the cylinder. See if the cylinder is distorted. I find 390s and 401s distort about .003". Common 360 blocks distort .002" to .003". 290s distort only about .001" or so. Publish you findings here so people can make their own judgments.

The head plate to do a valve job works well, especially on the end cylinders.

[jeepsr4ever]

See if the cylinder is distorted. I find 390s and 401s distort about .003". Common 360 blocks distort .002" to .003". 290s distort only about .001" or so. Publish you findings here so people can make their own judgments.


That is quite a bit of distortion.....are those numbers right? :shock: I guess I never checked it out...only ever had one block done up with plates

[Rogue Racer]

MC -

My records:

1 '68-'69 390 block - measured two cylinders, #2 and #6. #2 distorted .0033", #6 distorted .0021"

~'72 401 block - measured two cylinders, #1 and #7. #1 distorted .0031", #7 distorted .0026"

'76 401 block - measured 4 cylinders, #1 and #3, #6 & #8. #1 was out .0030", #3 was out .0017". #6 was out .0020", #8 was out .0018"

I have measured four 360 blocks, of unknown years except 1 which was out of '77 Matador. All would distort in the .0012" to .0025". The front two cylinders are worse than the others. I suspect this is due to less support due to the design of the block. I had one block which was a Jeep block that was better than the other three, for some undeterminable reason.

I have measured three 290 blocks and they distort less. All the cylinders except the front two would distort less than .001". Of course, the 290 block has cylinder walls that are twice as thick as the bigger engines and the cylinder diameter is less. Also, I was torquing the heads at 75 ft/lb on the 290 with a steel gasket where the other blocks were being torqued at 100 ft/lb with a composition gasket (FelPro 8266), if that is a factor.

[jeepsr4ever]

Nice...we need another post of usefull engine info :t:

[Mudrat]

Nice...we need another post of usefull engine info :t:
So get HOT!! You have the Collection (http://www.bulltear.com/forum/viewtopic.php?t=2467) 8)

Mudrat
Posted LIVE from Charleston!!

[fuzz401]

Mudrat
Posted LIVE from Charleston!!


you forgot:
Home of North America's Longest Cable-Stayed Span Bridge

[Mudrat]

you forgot:
Home of North America's Longest Cable-Stayed Span Bridge
True and the pics you sent were dynomite!!! Thursday they are doing the fireworks show and have about a mile of he river blocked off. The local NBC affiliate said they are going to to cover it all live. There are already folks that have RV's set up in the best viewing areas and are looking a 3+million people in the area to watch what is being advertised as the largest fireworks demonstration of the year in North America.

should be a blast hehehehehehhee

Pat

[Rogue Racer]

I have been looking for 343 blocks and the thick walled 360 blocks, just to complete the info base, but have not been able to find any in my area. I might not be able to afford the special 360 blocks, if someone knows what they have. I ahve a couple of 304 blocks here, but I have not done anything with them yet.

[Blown7]

The engine collection pics are nice, I have seen another collection in my life owned by another fellow that would match or beat the quanity in the pics. The guy I bought my 401's from. When I called him to answer his ad on the AMC forum I asked do you really have a 401? His reply was how many do you want? He had brand new NOS 401 short blocks and 360 4 bolt short blocks still in the Amc boxes!!! Not to mention used, abused and all kinds of sundries, AMX's, BBG's, 401 Matadors. 390's the same amount. His prices weren't cheap he knew what he had. He moved to Arizona for his health and I don't know if he sold it all or took it with him, the day I was there he had over 300 401 cranks. Anyone interested email me at jeffreykupiec@hotmail.com for his name and last known email. When I walked into his celler and shop I was with a soulmate lol. Jeff

[FSJer]

Has anyone heard of Platau'e Honing ( spelt it wrong ), another process of accuratelly honing cylinders to get close to a cylinder wall finish of an engine with so many miles already on it & at the same time getting a good ring seal.

most machinists in the past have hone cylinders in one process with between 280 - 400 grit stones , this produce's under a microscope sharp shands & points that quickley wear new Pistons & rings down & opens up the ring gaps like when you 1st run your engine in & change your oil , it is so dirty and has heaps of metal particles in it .

also there are heaps of different stones , diomand honing tips ,etc available now.

Platau'e Honing is normally a 2-3 process Hone , that takes the tops off most of those sharp points & shards off , but leaves enough valleys for the oil to grab hold of & your parts wear alot less , you don't have all those metal particles running around ( in run in ) & wearing eveything else.

I am going to build my 360 shortly for my FSJ , i will get my machine shop to do this with torque plates & if they can - with hot water running through the block, it will be a daily driver, but i want it for many years to come , getting to work in & fun on the weekend, funnyly enough this machine shop i spoke to today , also do cryogenics -Heat & freeze process of hardening components like tuftrided & nitrided but heaps better again,will get crank and a few other parts done.

Also ther is a site which i found while searching the nety about torque plate funnyly enough , that has heaps about the Platau'e honing process & use of torque plate ( specifically for machinists ) , i can get the site address and put it up here if anyone wants the specific's about it all , spin when i 1st saw it.

cheers
Rick :wink:

[Mudrat]

Has anyone heard of Platau'e Honing ( spelt it wrong ), another process of accuratelly honing cylinders to get close to a cylinder wall finish of an engine with so many miles already on it & at the same time getting a good ring seal.

cheers
Rick :wink:
Welcome to the board Rick -
Nope never heard of it (even if it was spelled right :wink: ) Do they finish the standard honing process with a hight grit - say 1200-1600, or ????

Pat

[Rogue Racer]

Performance cylinder wall preparation has always been a multi-step process. If you have ever tried to polish raw metal, do a show quality "no flaw" paint job or do furniture quality woodworking, you know that you have to do sanding in steps, using a finer grade sandpaper for each successive step, to achieve a finish that shows no scratches. Today's technology is just more exacting than what was available 25 years ago (even five years ago!). The "plateau" finishing that is referred to is an application of technology to achieve a super-fine cylinder wall finish with no burnishing. A web site that will introduce you to the basic understanding is from the Sunnen corporation:

http://www.sunnen.com/newsDetail.jsp?id=5&catId=42&flgArc=

There are CNC block preparation machines today that are capable of boring blocks off factory blueprints and finishing the cylinder walls to a programmable selected finish while sensing the hardness of the block and cutting quality of the honing process as it is running. Stone selection, speed of the honing head, oscillation rate (moving the honing head up and down the cylinder), and stone pressure are all controlled by the machine to produce the requested finish. Of course, you pay for the technology when you take a block to a shop that has one of these machines (inquire in the NASCAR circles), like $1000 to blueprint a block. But that goes back to the old saying, "You get what you pay for".

[Mudrat]

Thanks Rogue - I just had a 258 'balanced and blueprinted' by a local hot rod shop that builds race motors, and it runs STRONG! Don't think they went that far though for what I paid :wink:

pat

[FSJer]

Finally remebered to find the information i got from this site awhile ago specifically about Platau'e honing , use of torque plates , etc, etc . I found it extremely detailed , it spun me out when i read it all ( heaps ), here it is >>>

www.babcox.com/editorial/ar/eb40250.htm

Have fun
Rick

p/s : there's another site about torque plates , just have to remember the site .

[Mudrat]

That's a heck of an article Rick - Thanks!!

[Gremlin4ever]

Thanx for the added information as it all is added insurance to a longer running engine. I wont be turning 5 Gs on my engine but it has to help even though.