Thread: Block-fill for thin walls?

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This is more or less a follow up on a previous thread I asked about cylinder wall thickness. But seeing that my machinist may not have as much race engine experience as some on here do I have to ask.
Will block fill do anything to support thin cylinder walls (.100-.125) from cracking or melt down? This is a sbc 283 bored to 4". It will be a brackett racer and will be a 'carbed' motor with no bottle so no extreme pressures. Horsepower will not be over 400. Thanks.

then dont worry about the thickness, ESPECIALLY if its under 400 horse, dont worry about it. i run the same thing a 301, its perfectly fine. now if it had a 6-71 id say fill it. lol. just make sure you have a good radiator and pay attention to gauges <as with any motor>

100 to 125 is to thin the walls will move all over and the rings will not seal from the walls moving. that is what the block rock is for. i would not build a engine with 100 thick walls yes a short fill of block rock would help this . but i think you have a hand -grenade

I'll side with pat & 196 - both have valid opinions .......

IMO the block fill will stableize the thin wall block you created. I'd say .100 to .125 will be detrimental should you not utilize it. Anytime - race or not.

I'd also say if your trying to squeeze 1 HP per CI your looking for a window repair the first time that gem gets a bit of real heat in it.

I've run a 54 + .100 with good success with big comp. (14.1 to 1) & an older set of pro stock heads (EPD) & carb. intake running a clutch.

What I wouldn't do is spend a ton of cash on this combo as over time it will self distruct.........IMO. Find a solid 283-350 block & blow it over .060 - that'll last 4ever.

REGS

In the previous thread I mentioned,which was about cylinder wall minimum thickness it was stated by someone that Smokey Yunick had stated that .135" was the minimum he would suggest and of course he would probably add that this would be pushing it.
Any machine shop guys on here that have actually bored cylinders out .120-.125? (3.875"to 4.00")
Internet 'talk' has it that guys did this all the time in the 50's,early 60's? My motor is a 67.
Scooter,have you done this to other 283's other than the one you own now?

Originally Posted by FAYLUR

This is more or less a follow up on a previous thread I asked about cylinder wall thickness. But seeing that my machinist may not have as much race engine experience as some on here do I have to ask.
Will block fill do anything to support thin cylinder walls (.100-.125) from cracking or melt down? This is a sbc 283 bored to 4". It will be a brackett racer and will be a 'carbed' motor with no bottle so no extreme pressures. Horsepower will not be over 400. Thanks.

Also don't forget that the engine will run warmer.
I.M.O.,you are building a bomb.
If you want more hp just build a 383.

not to sound like a smart a$$ but i have a boring bar f2b rottler so i am a machinists have bore big block blocks out 100 over it just will not do any thing HP if the bock is moving all over the bores help tie the top deck to the bottom of the crank case. so you are making the block weaker.+ adding more heat less water by add block rock to off set the weak block and it can not be fixed if you loose a wall just not the way to go if your looking for some one to tell you it will be ok to run it ?

For drag racing, I would say why not add the block fill??? You know you are going to be stressing the block way beyond it's design limits, might as well spend a few $$$$$ and improve the longevity..... Kind of like adding a rev limiter, even though you don't need it until you miss a shift!!!!!!

block rock is the only way to run it. but is the pin pulled half out or in ?

Originally Posted by pat mccarthy

block rock is the only way to run it. but is the pin pulled half out or in ?

Would that be the pin to the "grenade"??

Originally Posted by erik erikson

Would that be the pin to the "grenade"??

you are right your sharp erik

Pat,,,,to be honest,yes I am looking to hear from people with experience like yourself. These 283's were bored to 301 often in the 50's and driven on the street but those early blocks were supposedly thicker castings but even some of those would over heat.
I need to hear from people like you people because I don't trust my machine shop for the reason that they would say bore it just to get the work.
As far as block-fill,if I did that would completely filling the water passages be a common practice for 1/4 mile only or do they have to do 1/2 fill and use some water?

i would fill it to the bottom of the water pump holes .yes you would need to do a sonic check i have short filled block that were hurt to and to help the block from moving and seal it .just that a pistons company makes the size pistons. it will not make it doable .i had sent out five 454 for a sonic check to go to over 100 and not all were good to go the big blocks have very thick walls. i would add this was along time ago and it just was not worth all the trouble and at that point they are throw a ways when bored out this far

i have a 71sbc 400 that is .30 over and i have a 144 weiand blower wanted 2 know if that was a good combo for street use in my 81 Z28 (the sled)and would it be 2 much 2 take it .40 over i will be using kb-30cc dish pistons 4 the lower compression and a 76cc head with steam holes also i have a built 350 turbo with a b&m holeshot 2400 and a eaton posi with 373 thanx

young audio, if your asking me I don't know a thing about blower motors but there are alot of guys on here that do. Post a thread with that in the title and you will get alot more response.