400 block 511. Whats the max amount you can have and keep it cool on the street?

The head bolt Casting boss will block your flow if you go to hi. I like at least a 1/2 inch below those boss' in the water jackets.

We fill to the bottom of the core plugs

But yes keeping it cool is a trick, I have a 528 on the street in a 71 Barracuda, it has a new large ali radiator with twin fans and I fitted a engine oil cooler but on a hot day on the highway it gets too hot.

I don't recommend using it
Especially if all the machine work is done

Ok, the shop that filled the block said it was above the soft plugs. They were not kidding, its way above the s plugs. I can stick my finger in the cooling jacket at the deck and touch the filler. 2 -3" below deck.

We have a high fill on the 440 block in the Barnyard Viper. Filled to the bottom of the water pump holes. We run an oil cooler, but still kills the oil on occasion. The water temp never gets over 200.

Looks like i will have to keep an eye on oil temp.

hard block fill is not the mod you really want to do to a street engine. i did it to an earlier build & even with a electric water pump the oil temp would soar when idling in the prestage queue. i ended up fitting an accessory oil cooler but once that motor went south i didn't bother repeating that mod. i use a girdle on my current stock block engine, that seems to be a better option imo.

I understand. My small block had a short fill and it was street driven often. Ran 195-200 water temp and oil temp was 230-240 in 75* weather.

Water temp will not be an issue..Oil temp will. Less water to cool so those temps will or should not get really high. Oil temps will be the issue

You need an 8 quart oil pan and a QUALITY oil.


That means an oil you probably can walk into a store and buy.


Not a fan of engine oil coolers.

Please explain.

Oil coolers are fine if the pump, and lines to the cooler, are sized appropriately. Lots of OEM applications have them, especially the heavier duty engines. Combustion heat has to go places, and with a filled block it heads to the oil.

The thing with the truck was, an old race engine got converted to street duty. Boone would complain about killing the oil on Drag Week, saying that when it ran over 240 oil temp for a period of time, it would start to burn it, and then oil pressure would drop fifteen to twenty lbs.

He always ran Valvoline VR-1 50wt. in it.

When I got the truck down here in Phoenix, I added a plate cooler that was 2 inches longer than the previous one, and switched to Lucas Classic 20-50wt.

Even though I have seen oil temps in the 240-250 range, I've never experienced pressure drop (solid 65lbs.) or burning, so I'm going to chalk it up to better oil choice.

It's not ideal, but sometimes you just use what you have.

I would find a different block and start over.

Yeah,
But I like driving them more than I like working on them, and as long as the old girl still slams me back in the seat, I'll keep beating on it!

It's a 440 source flat-top 4.25 stroke kit. topped with the old Edelbrock RPM heads/Isky ductile rockers that I've used since '99. Not once piece on that engine owes us a darn thing!

As said, water temp won't be the problem. Oil temp will. Personally, I wouldn't do it on a street application. If you decide to do it, I wouldn't go over a half fill - and count on using an oil cooler. On the plus side, todays lubes ( especially synthetics ) can handle ( and are designed to run at ) much higher temps than in the past. Running oil temps in the 250 range are not uncommon.

Its already done. No turning back on that block now.

I can only share my small block experience, but I bucked most of what is written in this thread.

1) I filled the block AFTER it was machined... checking the bore before and after it didn't move hardly SQUAT...

2) I never ran an oil cooler until I put a diaper on the car. Before that it never had any issue on the street. But once I put the diaper on it, the heat had no where to escape from the pan.

Mine is filled up pretty high (well above the freeze plugs in the side of the block... on a small block you almost have no choice but to do this because they are so low.) I can put my finger through the deck and touch the top of the fill, so it's up pretty high.

I feel like with everything, there is a lot of people perpetuating old wives tales from things they've heard.

Worst case it MIGHT need an oil cooler.... and at the absolute worst it MIGHT need to have the hone touched up. Hardly reason to throw the block away and start over...