Hey guys a recent conversation got me thinking. Anyone here done a short fill with Hard Block on a FH? Im thinking a 1" short fill will increase the strength in the pan rail area without affecting cooling adversely. Also discussed was adding cast iron filings to the Hard Blok mix to enable a similar coefficient of expansion as the parent cast iron block. For a blown strret/light strip engine, can anyone see any issues with this? I feel that oil cooling/water temp should'nt be an issue - esp at the bottom of the cylinder and such a short fill. Would love to hear of your thoughts on this one guys, fire away !! Rat
From the design i would say the Flatattack gridle is the best one! Don`t see a reason to fill the block.....don`t think it will strenghten it...
I don't really wanna run a girdle on this engine for the time it takes to adapt one inc pan mods etc. I cant see how a 1" fill from the bottom of the block can hurt? If I was to run a girdle, it would be on a MAX effort race engine, not a dual purpose ride like this one. As you all know the weakness in a FH is the pan rails and the bearing saddles. Strengthening bottom of the block will help....I believe a short fill could help in this area. The Hard Blok bridges the gap b/w race and street. I know of one dude down here who has done this with great success on both street and race engines, but was curious for input from some Stateside Flatheaders.... Rat
But if you pour some metal in there it will just sit there... No mechanical connection .....sounds a waste of time to me. How much power do you expect from your engine that you want to do that? Cheaters pete runs a 244 HP blown Flathead without anything. Antother friend runs a blown 276ci, no extra support. and we have a STRONG 304ci without any extra support. Oil pan mods would worth the little trouble if you use the Flatattack gridle(the only one on the market that makes sense to me).
Micky, the iron is mixed into the Hard Blok before it is poured. Bonds to the parent cast iron block and works very well in OHV engines. I know, Ive used it. With this FH, Im shooting for a little more HP/TQ than the builds you mentioned (of which i am aware of) and I've already been running a blown combo for 3 yrs so I know what the engine likes/doesnt like. A well known FH man here uses it, races with it and has it on the street and likes it - who am I to argue ? Just curious as to further input form over the pond - thanx for yours, keep em coming. Rat
Isnt that stuff more for lower cylinder wall support in modern thin wall Drag engines? I cant see it helping pan rails or bearing saddles at all from up in the coolant passages. Anyway, at the very least ,i would increase the capacity of the radiator by at least double the amount of the stuff you poured in. sorry if local opinion wasnt what you wanted!!
Not at all LS.... Have thinner walls that need more stability - check Also have some sleeved cyls - check Very short 1" fill that won't affect cooling - check Applying the KISS method - check Avoiding the cost/complexity of a girdle - check All in all, a lot of PROs above. In all seriousness, I can't see how a 30mm short fill could affect the temp that much; with a taller fill sure, i could agree that coolant/oil temps will rise. I have had OHV's with 1/2 fills still run fine and others need an oil cooler to due increase in oil temps but that is a simple enough addition if required. This is getting interesting....taking all opinions on board atm. Rat
surely plumbing a full flow cooling system would be at least as much work(and Money) as the sump mods needed for a more stout main cap setup? which is a more proven way of supporting the bottom end of a flathead. or are you doing both anyway? if so, then yeh chuck some concrete in it..cant hurt . I dont believe an inch of it in the bottom of the cooling passages will add anything to your motor, but if it doesnt make it run hotter, wont take anything away either. would be interested in knowing if any Flatheaders have done this also!
I still don`t believe that it is an alternative for a gridle..... You still only have the cast bearing caps.... On the other hand, if you have tried it before on other engines with good results.....why not try it on a Flathead. A 3 3/8 bore will get thin at the bottom so there it may help. Take pics of the work and show them on the HAMB !!!!! I always like to learn
Hey Micky (now where have I heard THAT line before haha) I have studded billet steel caps, H beams and a Scat crank in the bottom end. Yes a big bore will get this so it will help. Ill try to get the machinist to take pix and post em up. Rat
Do exactly as others and the best you can expect is exactly the same power, speed, longevity, etc. To improve [isn't that what roddin' is all about?] you have to try different things at the risk of set backs. Even more new ideas can come from any set backs if they are studied closely. Glad to see you are going for it. Keep tryin', thinkin', and let us know how it goes. Ed
Sounds ok to me, dump some in there if it makes you happy. But...i don't know of any block fill that bonds to the block itself. It supports by virtue of its' mass not adhesion. I know, i have used everything thing from selfleveling concrete used for machinery setting up to commercial blockfill to epoxy filler used in underwater cable spices. You stand a slight chance of some form of adhesion if you get a virgin block but with an old flattie and decades of rust, glycol, antifreeze and whatelse inside the waterpasseges you can't scrub clean you won't get a sound bond either. If you want piece of mind dumping blockfill in, go for it. Do you really think that it is bonding and the metal chips etc are going to match the expansion coefficient and act as if there were more base metal in the original casting?
Do you really think that it is bonding and the metal chips etc are going to match the expansion coefficient and act as if there were more base metal in the original casting? No I dont oj, but at least in theory it might work better thasn basic Hard Block itself. If it doesnt bond then what you are saying is that it supports by virtue of its mass. That it itself would be better than zero support down there would'nt you agree? I have also heard of people using tiling grout instead of the Hard Blok mix and havent heard of any issues. I really wanted to know if anyone had actually DONE this with a Flathead....thanx to all for their input and not to be at all rude, but Im lookin for real world input/experiences as well guys. BTW, just wonderin, why do you have the "Molon Labe" sig buddy? Rat
I have heard of complete blocks filled but have not heard of any done with your thoughts in mind. If you have any junk blocks maybe cutting into them may help you along so you can actually see where the blokfill will do it's work. My block which is still at the machine shop getting the larger valves cut also has studded steel caps on all three mains but my concern was without doing a girdle you still have the weakness of the webbing for the center main cap which I think is one of the weaker spots. My guess is that the webbing there will be first to go and there is no way to get any stronger in that point except for a girdle. If you get into it any further keep us posted, I would run a oil temp gauge and also when testing while running use one of those heat guns that you aim at something and it gives you the temp in case while the blokfill is in there that it doesn't lay in any areas that may hurt water flow in any certain area's more then others. Hurry up and get it done so I can have some good test results for my motor
I have run Hard block for years in many hipo motors and see no problem with what your trying to do. It will in fact give a little strength in the lower cylinder area as well and assist in reducing block flex. Currently I have a FH 304 filled but haven't run it as yet so I cant give actual results on my build. One thing for sure it wont hurt a thing.
Update: Engine is up and running and running just as kool as it did before the Hard Blok, so it hasnt hurt in that dept. Next step is the 4BBL and dyno - let's see what she does. For those who wanted to know. Rat
We did a lot of Hard Blok... and other brands with good luck. If the block is clean that stuff sticks and doesnt want to come loose. Yes it will help tie the lower end of the block together and strengthen it. We used to fill chevys right to the bottom of the water pump passages on circle track motors (before the after market blocks came out) with out any cooling issues.
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