Major Machineing question

[TweeT91109]

OK, I took my block to the machinist on Wednesday, I told them ill be bringing them the mains, today on Friday. I got there to drop them off, and my block is sitting there wrapped in plastic. I asked them if its required to machine the block with a load on the block from the mains. They said that the cast iron blocks don't require a load from the mains. I was like idk about that. They also informed me that F & H Performance didn't have the block machined with mains on and its running strong at 900HP right now. But again I think they may have just been trying to blow smoke.

So my question is, is it required to machine the block with a load on it from the mains. I would think it would be required, because when I put load on the block when installing the mains, it will move the deck of the block out of a straight line. And I really don't plan replacing the metal head gasket.

 

[IJ.]

Should have had the Caps installed and torqued correctly, Timing Tensioner and a Torque plate all torqed to spec... :nono:

 

[TweeT91109]

That's what I told them, but tjeu kept telling me it isn't needed. So it looks like I'm going back.

 

[suprarich]

The only 7m motor I know of that F&H is running with 900hp was machined by me here in Ohio. And it had the billet main caps torqued down.

 

[IBoughtASupra]

Are we talking about machine the deck of the block or the mains?

You need to have the mains on and torqued down to mill a block? Never knew that.

 

[TweeT91109]

yes we are talking about machine the deck of the motor. But they did it without any load on the block from the mains.

 

[hvyman]

Main caps are always supposed to be on. Crank in or out.

 

[TweeT91109]

Yes I know that, the machine shop said other wise.

 

[JStoked]

So when the motor is getting bored the mains need to be on? Or just for balancing?

 

[hvyman]

Mains should always be on unless your installing or removing the crank.

 

[JStoked]

Mains should always be on unless your installing or removing the crank.

My mains are on the motor but not torqued down do to i am getting arp bolts for it. so should i go and torque the old bolts down for the boar job ?

 

[hvyman]

Yes.

 

[JStoked]

k thinks for that info.

 

[suprarich]

For any performance build, every major fastener possible, that pulls on the block, should be torqued down while performing the cylinder hone, line bore or line hone, or milling of the blocks gasket surface.

For a stock OEM type rebuild, it is not as important for the reason that your tolerances are done in ranges of acceptable limits, rather then dead on balls accurate.

 

[vIetDrIfTeR]

im sorry i dont understand why the mains has to be on when being hone or bored? can u please give me some details on this.. thanks

 

[IJ.]

im sorry i dont understand why the mains has to be on when being hone or bored? can u please give me some details on this.. thanks

Everything that bolts to the block will distort it to some extent changing the finished hole shape and size, in extreme cases they run coolant through the engine at operating temps to simulate the thermal expansion the engine will see when it's running (think F1 cars)

They won't crank when cold so have to be preheated before starting.

 

[hvyman]

Thats crazy. Didnt know they get that crazy but i guess if your going to run a engine the way they do everything has to be there.

How do they do that a inverter like hybrids or just block heaters or something?

 

[IJ.]

Thats crazy. Didnt know they get that crazy but i guess if your going to run a engine the way they do everything has to be there.

How do they do that a inverter like hybrids or just block heaters or something?

External life support system that heats and circulates the Coolant and Oil until the block temp is ready to go.

 

[Poodles]

My mains are on the motor but not torqued down do to i am getting arp bolts for it. so should i go and torque the old bolts down for the boar job ?

If you're going ARP, you need them before the machining is done. They load the block differently as they're studs.

 

[TweeT91109]

If you're going ARP, you need them before the machining is done. They load the block differently as they're studs.

OK well I ordered a bunch of ARP hardware. So I wont take it back till I have those in hand. I'm really just thinking of cutting my losses, and taking it to a different machine shop.