machine work questions.

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MidTexCuda

MidTexCuda

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Deep in the heart of Texas
Well my 400 block got a clean bill of health from from my potential builder today (local vendor my company does work with)
The block is 60 over but has plenty of wall. It will be touched up with the hone for the new slugs (from cast to forged). Here is my issue.... the guy says we dont need (nor does he have) torque plates for the motor. I am nervous. This will be a healthy stroker street build and I want to get it right. Should I send it out for the machine work to someone who has the plates? Will the 60 over make a difference between honing with or without the plate?
 
Yes by all means! The plates will pull the block/ bores more into line with where they'll be when the heads are torqued down. Ask some of the guys on here that are actual machinists (MRL, Moper, OU812- Brian) & they can probably tell you how much a bore will move when the plates or heads are torqued down. It's significant enough.
You can do it without plates, like if it were just an ordinary rebuild & be ok, but you'll be leaving some power behind if you don't.
 
Normally, I wouldn't give it a second thought, but with a hot stroker motor I would recommend a torque plate. Some people do it on everything.
 
A bore that is already .060" over (4.402) is already the diameter for the .060" over forged piston. The piston will probably be 4.397-4.398 for .004-.005 for the generally recommended forged piston to wall clearance. If the bore is worn not at all or maybe as much as .008", by the time you install the deck plate and hone the walls straight and round the bore will be 4.407" to 4.415" for .009" to .018" piston to wall clearance. I don't tell people what to do, I just kinda point out the facts. Hopefully the bore is still under .060 over.
 
Ask yourself this question--- Are round cylinder bores important to me?

If the answer is yes, then use torque plates.

NuffCed !!!
 
When file fitting rings, you guys use a torque plate? I don't know.
 
pishta said:
When file fitting rings, you guys use a torque plate? I don't know.
Click to expand...

When checking rings, you push them down below where the head bolts distort the block, and even so, any distortion would be unmeasurable on a ring gap.
 
MidTexCuda said:
IQ ----does that mean I dont have a viable block. I dont want to ship to a person with plates to find out my block is DOA.
Click to expand...

I took it to mean you need to the bore diameter where it is now before proceeding. I could be wrong. It's happened before.
 
If it were mine, I would get custom pistons and hone it with torque plates. The difference between how well an engine honed with torque plates runs vs one that didn't use them is noticeable.
 
Think of the block as a foundation for a house, if its crooked the doors aint gonna shut right !!!!!!
 
Thank you for the replies.
I have always heard you should use the torque plates and I understand the principle behind it. But when a seasoned builder tells you that using them is not a huge issue you revisit the idea... then you Google it... then you hear about steel vs. alum plates...attaching the mains... letting the block sit up... the idea behind the block being up to temp when honed ect ect.
Then you arrive here, with the people that have been there and done that.
I think my mind is back on track and that I will find a good MOPAR builder that has what I need.
 
pishta said:
When file fitting rings, you guys use a torque plate? I don't know.
Click to expand...

Yes I do. When honing the bore and fitting rings I make sure I have the torque plate bolted down with the thread depth I'll have with the cylinder head bolted down and I use the same type of head gasket that I'm going to run and torque in the same sequence with the same thread lube and torque values.
 
MidTexCuda said:
Well my 400 block got a clean bill of health from from my potential builder today (local vendor my company does work with)
The block is 60 over but has plenty of wall. It will be touched up with the hone for the new slugs (from cast to forged). Here is my issue.... the guy says we dont need (nor does he have) torque plates for the motor. I am nervous. This will be a healthy stroker street build and I want to get it right. Should I send it out for the machine work to someone who has the plates? Will the 60 over make a difference between honing with or without the plate?
Click to expand...

Mid Tex,

At our Machine Shop {New York}, we always bolted on a B-H-J Torque Plate, and bolted on a Cylinder Head
on the opposite side.

You would be surprised at the 'distortion'.

We usually bore out the Cylinder to within .0035" with our Rottler Boring Bar, and finish up the Cylinder
Walls with our Rottler Cylinder Honing Machine.

Twice Honing, {A} with AN-200 Stones, and {B}with AN-400 Stones for the optimal finish.

There is no short-cut for for precision.
 
MidTexCuda said:
IQ ----does that mean I dont have a viable block. I dont want to ship to a person with plates to find out my block is DOA.
Click to expand...


Well it means you may not have a viable block for a .060" piston. As Rob says, it needs to be checked out. And as was pointed out, a custom oversize piston is an option.
 
Just Maybe,

Your Machine Shop doesn't want to go for the 'Bucks'.

These B-H-J Torque Plates ain't cheap.

$400 Plus

yhst-58082516732612_2271_52857788

 
can you guys give me a short list of builders you would recommend that wont break the bank?
I know of only one person here in Texas but have never used him.
 
Also keep in mind that with the bigger the overbore, the more critical cylinder distortion can get.
 
Two places up here in Arlington Texas would be Arlington Automotive Machine Shop and Reher & Morrison, I dont have any numbers handy but could dig em up or the internet can dig em up for you quicker.
 
Automotive Machine and Supply Inc.
212 Carroll st.
Ft.Worth, Tx.
817-335-9331

automotivemachine.com

Don't think Reher and Morrison has too much Mopar stuff.
They do some Hemi head stuff though.
 
Old slugs cast and forged used to be .060 over out of the box and then you would clearance the bores as needed. Now they typically come with the clearance "built in" to the piston size. This means the new pistons will typically be 3-5 thou under the .060 overbore.

Before you worry, I'd give the shop a quick call and ask him for the actual bore sizes. Then you can contact the piston mfg and ask them for skirt dimension and required clearance. You may / may not find a shelf piston to fit your needs.
 
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