Printable View
does any one know what years the good two bolt mains were maid? becase i have seen a lot of stuff about the "good 2 bolts"
i am a bout to switch to a 4 bolt but i dont wanna have to spend more money than need me if im liky and might have a good 2 bolt on my hands any way thanks guys an girls
john
I am guessing u are talking ab0ut a chevy 350 2 bolt block. Most engines are 2 bolt and work well that way. Its possible 4 bolted mains are really overkill for some jobs. First decide what u want your engine to do, then start to gather parts. Hope this helps.
early 327 chevy's were 2 bolt main Dh
283's are 2 bolts.
John, when you say you have seen a lot of stuff about "good 2-bolt mains", where have you seen this??
As far as I know, a 2-bolt main block is a 2-bolt main block. I've never experienced good or bad.
A 2-bolt block will take just about anything you can throw at it up to about 7,000 rpm's and/or 450 hp in my opinion. Above that, you may want to consider a 4-bolt block.
I've never seen a streetable small block that was hurting from two bolt mains. The pistons or cam will go long before you need worry about the main caps.
With the gas available at the pump today, no way you can run enough compression on a street engine that you will pull a web. On a 9 or 10 to one street engine, the 2 bolt blocks will do just fine.
I'm with Tech, far as I know all 2 bolt chebbie blocks are created equal. Good or bad is determined by the quality of the machine work done to it and the skill of the man putting it together.
not so much seen but herd an yes im talkin aobut a 350Quote:
John, when you say you have seen a lot of stuff about "good 2-bolt mains", where have you seen this??
Guys correct me if I'm wrong, but didn't some years have more nickel content than others?
Once the oil pan goes on, no one will be able to tell the difference. Build the two bolt and tell everyone that it is a four bolt if it makes you feel better. Only your hairdresser will know for sure.
Ed
I've heard that too, Ken, but have no idea how to determine high or low nickel content.Quote:
Originally posted by NTFDAY
Guys correct me if I'm wrong, but didn't some years have more nickel content than others?
I have "Heard" of a similar thing that there was a run of years where the blocks were weaker....but don't know the details.
No matter what could he get a Stud Girdle to bolt on his small block chevy 2 bolt if he wasn't confident in it? Either that or get the block machined for splayed aftermarket mains...which I'm sure would be pricy and overkill on street! Just a couple of suggestions if he's really worried about his block. Anything can be done if you want to pay for it!
I heard that there was a mexican casting or something that was better
:) When looking for a block with a high -nickel, high tin mix, the numbers to look forare "010" and " 020". They are cast under the timing cover area.Quote:
Originally posted by techinspector1
I've heard that too, Ken, but have no idea how to determine high or low nickel content.
what do the numbers on the back of the motor mean? not the casting number, but the ones in the area behind the flywheel.
On blocks with a stronger nickle tin combo there is a third # usually .015 and as for the mexican block they have an M in the casting # and no the M is crap metal. Look for 2 bolts w/ 3 sets of .0xx #'s not just .010 .020 those are standard.Quote:
Originally posted by riverhorse59
:) When looking for a block with a high -nickel, high tin mix, the numbers to look forare "010" and " 020". They are cast under the timing cover area.
:confused: :confused: M.C. Where did You get that information? I'd like to look it up. I dont seem to be able to find it in my small block books. Thanks.:)Quote:
Originally posted by MalibuChevelle
On blocks with a stronger nickle tin combo there is a third # usually .015 and as for the mexican block they have an M in the casting # and no the M is crap metal. Look for 2 bolts w/ 3 sets of .0xx #'s not just .010 .020 those are standard.
Hum, thats pretty interesting, I've always heard about the high nickel blocks but nobody was ever able to explain it (or didn't want to give up the secret) will this hold true for the 400 blocks ???Quote:
Originally posted by MalibuChevelle
On blocks with a stronger nickle tin combo there is a third # usually .015 and as for the mexican block they have an M in the casting # and no the M is crap metal. Look for 2 bolts w/ 3 sets of .0xx #'s not just .010 .020 those are standard.
Never heard anything about "good" Chevy small blocks, but there are Ford small blocks manufactured in Mexico with a higher content of nickle.
here is a quote from nastyz28.com
Q: What is a Bowtie, or heavy duty (nickle) block and do I have one?
A: Tin and nickel are two metals that are commonly alloyed with cast iron to improve durability, hardness and heat dissipation. Some production engine blocks have the numbers "010", "020" or both cast into their front face, just above the main bearing bore. (The timing cover must be removed for these numbers to be visible.) If both numbers are present, one about the other, it indicates that the block alloy contains 10% tin and 20% nickel. A single number, either a "010" or "020" represents the amount of nickel and indicates negligible amounts of tin. No numbers, other than the casting numbers that are typically found beneath the timing cover, translates to only minor amounts of tin and nickel being present in the block alloy.
However, cylinder wall thickness is the overridering consideration - and a block with no tin or nickel and thick cylinder walls is generally preferable to a high nickel block with thin walls
Dont know if nasty knows his nickel or not. Also, an interesting tidbit: Tyler Pipe in Tyler Texas casts water pipe using 100% recycled engine blocks and heads.
Actually, I think thats supposed to be 1% tin and 2% nickel, and it translates to them being less prone to cracking, and having a much longer bore life (cuz theyre much harder), which is a good thing.
LOL Flip it over on the stand and write "Denny" and youll have a DennyW engine. :D
:) This may help clear up our information on this thread and also the thread on the 307 engine.
307 engine---- In 1968 this engine was introduced to fill the void left by the 283 engine. Using the then new large journal crank, it retains the bore of the 283ci block,but uses the 3.25 stroke of the 327 engine. It is not a particularly desirable block,as most of them were cast with very little nickel and no tin to improve the cast mix. This was an attempt to lower the production cost of the bottom line engine. It seems to have an increased bore wear rate
because of that.
I took this word for word out of the Motorbooks International ,
Chevrolet small block V-8 ID guidebook.
It also states in its Engine Blocks section------
When looking for a block with a high-nickel, high tin mix, the numbers to look for are "010" and "020". They are cast under the
timing cover area. They show a picture of a block with both those numbers cast there.
My 4-bolt main 350 motor has both those numbers cast there.
As we discussed earlier you can make a 350 or a 327 out of a 307
but ,this shows us that it is not ideal . As I suggested earlier, this may work fine for a good little street motor ,but for any all out performance----Don't go there.
Malibu Chevelle, I'd still like to know your source of information,as I can't find anything like what you suggest. It may be so but I just cant find it anywhere.
The most desirableble 350 blocks were the early 70s blocks called the K series. They have a K prefix on the serial # and a K before the casting # and a K on the main caps. By 1978 the blocks were lighter and not as strong.
Any block made in Mexico is stamped "hecho en Mexico" Many of these were sold over the counter at you local Gm parts dept. Hope this helps. Gene :)