I just picked up a 400 SBC that has been sonic checked, magnafluxed, align honed, and bored 60 over with a torque plate. Casting number 330817. It has also been hard blocked 3/4 of the way up the cylenders. Am I going to have a cooling problem, or will this be O.K. and the engine will just be indestructable? I am going to be using TRW forged flat-tops, GM forged crank, Ultradyne hydro-roller, and some ported L-98 alu. heads (already have steam holes drilled). After some chamber work and some thicker head gaskets I am shooting for 10.5:1 compression. The cam specs are: 112 LCA 210/218 duration @ .050" and .495"/.495" lift. I have a Lars tuned 750 vac. sec. Holley and a Edelbrock Performer Air-Gap to go with it. What do you guys think?

 

I've seen several examples of street driven engines with the blocks filled to the bottom of the freeze plugs, and they have not overheating problems. However, 3/4 of the way is probably borderline. The cylinder heads and the top of the bores are exposed to much more heat than the bottom of the bores, that's why it's usually not a problem. I just wonder if filling them up 3/4 would restrict the coolant flow and volume too much. That sound smore like a Sprint Car deal to me.

I would also recommend rehoning the block after the block is filled. Some block fillers expand slightly after they cure and harden, this would probably cause minor distortion of the bores. The hone would be very light, just enough to clean it up.

 

make sure the hard block was put in before the block was bored and hone because it will disstort the bore as it hardened. i have run circle track 400 block engines with the block filled part way up with expanding grout and had no problem with heat. there is no heat at the bottom of the cly but you do lose some water volume. :chevy


[Modified by clem zahrobsky, 12:58 PM 4/3/2002]

 

The block was setup for a circle track guy who couldn't come up with the money after all the work was done on the block. I was able to pick up the block, new pistons, moly rings, crank, harmonic balancer, and a Lunati solid-roller circle track BIG cam for a song! I have not checked the hard-block fill myself yet, but I got the whole thing for $500, so I don't think that I did too bad. I will check the hard block fill and will probably try it anyway. If it works, great! If not, what suggestions to keep the car cool? Big radiator (the car came with A/C, so it has a 4-core in it now)? Also, I was planning on using an Edelbrock Victor water pump anyway (got one on the 84). Would that help? I just want those 412ci bad! Also, the block was honed after the fill, so I should be O.K.


[Modified by compuvette, 3:09 PM 4/3/2002]

 

Hey, how do I get the little "Cruise-Inn III registrant" thing on my avatar? I have been signed up for a couple of weeks now and just want some recognition! J/K!

 

That's a race car only idea. The only time someone ever fills the block 3/4 full is for methanol racing and they actually have a problem getting heat in the motor and they want a ridged platform for high HP. I had a race motor that only had water in the heads.

The only other filled blocks I've seen are stroker motors. They only epoxy the very bottoms where they have made the cylinder walls thinner from grinding rod bolt clearance. And this is way down on the piston skirt area.

You could take a chance. :rolleyes: It's true that the bottom of a cylinder bore is the coldest because it's not subjected to the heat from flame. When you say 3/4 filled is it 3.750 inches down from the top of the block surface?

The reason why I ask that is. The piston spends quite a bit of time at BDC and the rings are subjected to a complete change in loading from piston direction change. I don't think that a motor that didn't have cooling in this area would last very long.

Another way to maybe get away with using this block is to limit the compression and HP. The higher each of those are the more heat. Another option would be destroking like a 3.50 inch large journal crank. I have also seen 400 blocks with external cooling lines on the sides of the block and a line allowing flow from head to head by the distributer.

 

When I get my eyes on the block I will check it out for the distance from the top of the block to the hardblock. I guess we will see. What would you guys guess is a safe level? 4 inches down?

 

From what I've seen, anything below the bottom of the freeze plug holes is okay, you shouldn't have any cooling problem. Above that, it's probably a wait and see deal.

I've got external cooling line from my water pump to the cylidner ehads between the two center exhaust valves. This is pretty common with 18* heads, but it may help some for you as well. Most aftermarket heads have a boss in this area below the two center exhaust ports that can be tapped for this.

 

Monty, just talked to the guy I am getting the block from. The hard block is just to the bottom of the freeze plugs. Looks like I am O.K. Also, what does that really do for me? And how much HP can I trust that 2-bolt with? I am looking at a bigger cam (112 LCA 242/249 deg. @ .050" .540/.559 lift) and want to make sure all will be O.K. Thanks for all the help so far, guys!

 

Sounds like you should be okay then. The Hardblock will stablize the bores, giving you a better piston ring seal. It's hard to beleive, but cylidner walls actually move around and distort under normal operating conditions. When the cylinders are overbored, some parts of the cylinder wall can get as thin as .125" or more. Some Ford guys even run with cylidner wall thickness as little as .090" in some spots. The Hardblock will alleviate alot of the movememnt and distortion, as well as fill any areas where the the waterjackets were broken into if they were clearanced for a big stroke crank and rods.

As for the 2-bolt, I feel it it has more to do with rpm than hp. It;s not really the compressive loads from high cylinder pressure that breaks parts, it's the inertial loads created by high RPM's. I'm guessing with that cam, you'll probably see HP peak somewhere around 6500 or so. I think you'd be fine with that rpm and somewhere around 500-550hp. I assume you're going to use ARP main studs?

 

I am going to buy a two bolt ARP stud kit next week. I was planning on doing that anyway. The HP peek with that hydro-roller cam and my head flow numbers on DD2k is at 5500RPM so I was going to redline at 6K. Sound reasonable?

 

DD2000 predicted a 5500 rpm HP peak with a 242/249 roller cam on a 400ci engine?

 

With small tube headers and L-98 1.94/1.5" bowl ported heads. That's what I came up with. You are thinking 6500? Thats cool too! Also, with that big of a cam, will my low end torque be O.K. with 3.08 gears? I can swap if I have too, but I figured with 412ci I would be O.K.

 

I forgot about the L98 heads you are using. With those heads, 5500 is probably right for peak HP, but it'll be a torque monster. You'll be able to light 'em up at will.

 

Sweet!!!!!!!!!!!!!!!!! Billowing clouds of smoke while I charge past my buddies '02 auto vert! I can see it now!