I did a search and couldn't find too many examples so perhaps I suck. Anyways,provided it sonic checks well, where do you guys feel is a comfortable limit on one of these thick web blocks?
I have a 13.5:1 E85 499" build in the works that will have ported -1s on top so I'm guessing 775 HP on nuts. I'm pretty sure that's safe, but I don't think that's enough for me so I'd love to spray another 150-200 to it.

For those that have put a lot of power to one, did you have aluminum mains, girdle, half-fill, etc? This one has aluminum mains, but no block filler. Unfortunately it's already been machined.

I have a 230 block at the machine shop being done,will be a 540,had a 630 block 540,but the mains and caps fretted,so im tranfering the internals in the 230 block,will be cemented

My old 630 block with four ductile iron sleeves made over 725 HP with a set of SR heads on Oregon pump swill. I had put a set of Indy CNC ported 440-1 on that same short block and they made 775 HP at 7000 RPM on the same fuel It is still running today with a lot of laps and street miles on it. I did transfer metal from the block to the Mopar brand ductile iron main caps when it had a set of 906 heads on it making a tad over 600 HP, I took a flat mill file and removed the metal from the caps and blcoks twice during refreshenings on that block, no bad results so far My current bracket car has a cold weather thick main 230 block that made 676 HP on E85 with a set of CNC ported RPM heads and a single E85 Dominator carb. I may take it apart this winter to look at it, I replace the Eddy RPM heads with a set of Eddy Victor M.W. heads last winter It has the type same main caps as the first one did.

If one were to fill a block after machining, is it just the cylinders that will need to be honed again? Line bore should stay put, right?

Don't fill it If you do decide to fill it don't use a cement based filler

I have read how some don't like the filler. Have you had a bad experience with it?

Call up Koffel and talk to them. Those guys have built high hp 400 blocks for many, many years. That is why the B1 head is designed for the low deck.

GRP or BME rods and let it eat IMO.

I had a 230 block, half fill, 499 cu in, 13 to 1 ross pistons, BME alum rods, callies 4.150 crank, alum main caps, 1150 domi converted for E85, indy sr heads that flowed 335 int, max wedge ports, indy intake, 650 comp solid cam, crank trigger, vac pump, etc. NO girdle on it just main and head studs.
On the dyno it made 771 hp and ran great for many years. I sold the car and I believe it is still running yet.
It's the car in my sig.
David

p.s. I forgot to mention I hit it a few times with 250 hp of NOS and it loved it. The car had a bunch of stuff that needed updated. Drum brakes still on all for wheels, 3500 lbs, regular shocks, etc which held it back on the ET's.
It ran 10.20's all day long, 1.35 best 60' average of 1.37,
134 mph, With the NOS hitting it at the 60'timer went 9.29 at 145 a few times but I kept breaking the convertor so I quit using the NOS. Shifted normally at 7300 went thru at 7500,
when the NOS was on it went thru at 8100 I believe.

It was a Great car and trouble free other then the conv when using the NOS. I think I had the engine together for 6 years before I sold it with NO issues or troubles.
David

I've seen the Moroso brand cement filler shrink away from the insides of the blocks after curing on one Hemi block I did It had moved the center freeze plug on the passenger side causingit to leak coolant so I pulled it and replaced it is the onlly reason I saw the shrinking One other reason is on a customer SB that had been fiiled by one of the better Mopar NHRA class racer engine shops back east in MI we saw two different engine block temps with a infra red handheld temp. gun, 180 in the filled area and 130 in the upper part where the water was circulating from the dyno colling system Not conducive to ring seal and ring life, in my opinion and experiences

I would do what you are thinking. It should run hard. But I would start looking for a good block because you will want more.
I hit a hi compression, stroker 440 with hi boost 40 times before I got nervous. I have a crank trigger and EFI so my tune is fairly stable.
It was 3100#. The Wallace racing calculators spit out an unbelievable number!
Time slip

i had two different shops tell me that every 230 thick web block they sonic'ed had thin cylinder walls and one block had what looked like the core was installed incorrectly as the minor and major thrust were the thinnest part of the cylinders with the front and back being the thickest. i also have a 230 block, but it is not the thick web block and it too has thin cylinders. from what i'v seen the 230 blocks seen to run on the thin side for cylinder integrity.

I have experienced the same thing. Every one I have ever had sonic checked has had at lease one thin cylinder. All the 76-78 blocks "thin wall" blocks I've checked have been thicker.

Thanks for the input so far. This is primarily a street car so at least it won't get hammered all the time. I'm even considering changing pistons and slapping a turbo build together since those seem to be easier on bottom ends.

I have never had an issue using the Hard-Block brand of filler. I generally do a TALL fill on a race motor

The issue that most people have with Hard Bloc is they don't prep the block properly. Need to sand blast the water passages to remove 100% of the rust/scaling then rinse clean to remove the residue and immediately concrete the block before flash rust occurs.

Yep, my 72 truck 400 has real good 200+ on the thrust sides and although I`m not makin killer power, I may spray this pig soon so I can catch WETFART..........

Have been running a half fill(top of freeze plugs)of Hard-block on my 440 block for 14 years, no issues to date. The block was cleaned prior & used a deck plate on it.

After working at Pettis and seeing the affects on filled blocks I didn`t fill mine but it was squared, bored and torque plate honed about 14 years ago and although not stellar, it`s still goin strong.......