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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?
Also don't forget that the engine will run warmer.Quote:
Originally Posted by FAYLUR
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 ?:whacked:
Would that be the pin to the "grenade"??Quote:
Originally Posted by pat mccarthy
you are right :3dSMILE: your sharp erik:3dSMILE:Quote:
Originally Posted by erik erikson
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.
theres a guy here who bores his 350's .80 and .100 and they dont just explode, come to think of it neither have any of the 301's ive seen:D **)
no it will be down on power from the walls moving all over the damn place i do not think any one said it could not be done. it is just not that smart
And I have to ask again... Why would you NOT use block fill??? Such cheap insurance to keep those thin walls from moving around all it can possibly do is add performance and longevity to the engine.Quote:
Originally Posted by gassersrule_196
I use block fill on anything that is going to the track for the performance improvements it brings to the engine by keeping the cylinders stable.... the fact that it helps keep the engine together is just a bonus....
seems like block fill would make them run hot, ive only ever seen guys use block filler on blown motors
i ran two big block on the street with a short fill they did not run that much hotter than one with out. all the heat is at the top of the block and two inchs from the top of the deck but when you build something like this you should do a short fill
Biggest problem I ever had on engine temp when drag racing was getting heat into the engine quick enough to have it a temp for launch time.... Sometimes, like in a Friday night Gamblers race with quick turn time the engine got a bit warm but never a real problem. Even had it in a couple of street engines with a small fill and no heating problem.Quote:
Originally Posted by gassersrule_196
The block fill sounds like a good idea. Dad had one of these motors in a 56 chevy when I was young and at the strip we would come off the line at 7000RPM but that was a early model 283 .125"over with thick walls. I would be worried sick taking this motor that high if the walls come out thinner than around .150"+ with out block fill .
I havn't had it checked or sonic'd yet but it's amazeing what a difference you can fill in thickness reaching thru the water hole and pinching the cylinder walls between the thumb and index finger in comparison to a late 70's Ford 302 sitting 20 feet from it. The 283 feels alot thicker so they must have more meat than most other small blocks.
ford 302 block move all over just from honing them it is not a good block to compare to
I agree**) There are also different levels that you can fill to. The first stage will "help" a good drag/ street engine run. The last stage is for all out racing.Quote:
Originally Posted by Dave Severson
What Pat says here is very true.Quote:
Originally Posted by pat mccarthy
You can bolt on a water pump on the newer 5.0 blocks and pull a front cylinder out of round on a .030 overbore.
watch out erik hear will come the hate mail:3dSMILE:
Sometimes the truth does hurt.:DQuote:
Originally Posted by pat mccarthy
yes when you build a stock 302 block you need a bag of cement:D
:LOL:Quote:
Originally Posted by erik erikson
Both motors are .030" over,well the Ford 302 dropped a valve,,,so in one spot where the valve tried to escape that area is about 2' over:CRY: I couldn't believe the effy(effie?) still drove about a half mile before locking up even though the largest piece of that piston that was left was about 1" square. NOW,,,,if it had been a chebby it would still be running!:LOL: :LOL: :LOL: (might as well get the hate mail going good!):p :LOL:
well i have fixed big block chebbys that have lost there lunch i do not think there is many engine that you can use the old block over them chevys are tuff