4 hours ago in News
There’s fast and there’s FAST–and then there’s this thing.
I just had my block magnafluxed and it came back OK, but it will need to be bored .060 over. Any one have words of wisdom to either do it or not. The car does not weigh that much and the engine will be put back into fairly stock form (no major power adders). Any thoughts or tips are appreciated.
I dont have any ford specific knowledge, but for a stock engine boring it that much is usually ok. I wouldnt put any expensive machine work into it though, becasue thats probably last rebuild for that block. I have heard of a chevy small block (just a cheap remanufactured one) that was bored .080 over and lasted a long time with no problems.
Depending on your intentions I rebuilt a .060 5.8L with a roller cam conversion from Crane, a TFS cam, GT40 aluminum heads, 1.7:1 roller rockers and 10.5: CR, with an Edelbrock Performer RPM intake and a 750cfm carb. It was a stout runner. Never on a dyno.
Have a machine shop sonic test the block for a read on wall thickness and if there's enough meat to safely bore to .060. I don't know how much wall thickness is recommended though, but the information has to be out there somewhere, the shop itself should have manuals that explain this for this specific application.
I've done .60 over on a 351 for a boat motor, no problems at all. A good set of heads (VERY important) and a bit of cam, you will have an excellent motor. Cam selection will decide what you get out of it. They are stout.
.060 over isn't usually a big deal except on castings that are well known for core shift - don't know specifically, but sonic testing can tell you for sure. Keep in mind you're actually getting a bigger engine - small difference but hey - not in a bad direction.
Are you doing the assembly?
If you have the time I would recommend working on oil return to the pan. Get some of your favorite libation and spend some quality time with the block grinding off all Th casting slag and what not in the motor. Other than that I would get the rotating assembly balanced. You can do alot of this your self with a scale and a grinder working on the pistons and rods. Then send it out. I think I had it done for $150 the last time. I do this to every motor I build even if the rest of it is going to be stock components used in stock form. When you get things balanced make sure to include the clutch assembly and the flywheel. This basic recipe has had many otherwise stock 4AGE's I have built go places in the RPM scale that I would not have dreamed of and they survived. Motors like to be in balance and the cost is minimal. I look at as just good standard motor assembly practice.
What year block is it? I remember reading that blocks from the mid 70s through the mid 80s are poor casting and prone to cracking.
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