Thanks for the insight. I did not know about it. I wish i would've bought the 4.005 pistons you had for sale

 

Good question. im in the same boat myself. I lost a piston on my factory lQ9. so i took it to my builder he ended up boring it .020 over. well then he put all new factory parts in it then i bent a stock rod on boost 3k miles later. so now i have a block thats bored .020 over with less than 3k miles on it and the walls look great. so im wondering if i should just get custom pistons or finish boring it to a 370. which would only be .010? heres a pic of the cylinders i dont really want to bore a good block

 

As long as the bore is true or square as some call it thats the biggest concern. A light finish hone and slap her together.

 

if you have it apart i would have it checked and if it needs it cleaned up... whatever you do just hurry up and get to it.


470 is a rediculous price. the guy i deal with told me between 125-150 to make me a 370

 

Yeah the price without the torque plate is around 200 bucks but a torque plate hone is like an extra 200. I'll call to find out about the 0.005. I want them to change out the cam bearings and freeze plugs anyways.

 

Found a cheaper price of $300 for the bore, doesn't matter if its .030 or 0.005. A light hone is $120. **** is expensive.

 

I just went out and measured my block and the cylinders are right at 3.990" Is this normal?

 

i just got my 6.0 back from the machine shop, same as what your doing forged .005 over pistons. they said it had to be bored, couldn't just hone it. cost about 170 bucks for the bore/hone..don't know if they used a torque plate or not, small block ford torque plates are supposed to fit ls engines

 

What are you measuring with? You need a cylinder bore gauge set up in a calibrated mic set at 4'' at 70* temp. Also good to use a tq plate, with the mains torqued up. You can also use a cyl head insted of a tq plate and measure from the bottom.

They are feeding you BS. When boring a block you should allow at least .003~.005" hone stock to effectivly remove the machine/fracture marks from the boaring bar. So on a 4.030" over bore you would bore to 4.025" and then hone to 4.030''. If you are taking a factory bore 6.0L from 4.002" actual bore size to 4.005" it's cake if you have the right equipment. With a honing machine I've seen blocks honed as much as .020"~.030" with no problem.

 

I was just using a set of calipers that i have. Probably not the most accurate but its what i have. I could see the temperature affecting it too. It was -22*F in the garage last night.

So getting a 4.005 bore should only involve honing correct? No boaring? Ill have to talk to the machine shop about it later today.