The block I have says 80-85 2 or 4 bolt mains according to Mortec.com

I have heard the 2 or 3 freeze plug method, but it seems like I also heard that this method is not reliable either. Is there any way to tell for sure?

casting number is 14010207

The engine is assembled for now, and I'd just assume leave it that way until I decide what I want to do with it. Which means not pulling the pan...

Get a borescope and look down the oil dipstick hole in the block and view the main bearing cap.

That's the only way to tell unless you have a small video camera and go through the distributor hole.

You might be able to look through the oil drain plug hole and a very small mirror.

------------------
Everett "OBJECTS IN THE MIRROR APPEAR QUICKLY UPON RAPID DECELERATION"

not 100% sure, but if it's all original and together, i THINK the 4 bolt engines got an 8" balancer. the freeze plug method only works on the 400 blocks, and even that doesn't mean anything. if it isn't installed in a car, it isn't that big of a deal to pull the pan. you might get lucky and not need to spend the $10 for oil pan gaskets, but they usually are a good idea to replace before installing it anyways.
in the end, it really doesn't matter if it's a 4 bolter or not. they aren't supposed to be that much better than a 2 bolt block, until you try to sell it to someone who's cousin's uncle's friend's father-in-laws third cousin twice removed once told you that they read 30 years ago that a 4 bolt block automatically means you have a 500 hp engine. it just really doesn't matter, at least not for stock blocks on mild (under 450 or so hp) steet engines.

------------------
1971 Nova(looks like 69 camaro from underneath!)
355sb, vortec heads, HOT cam,T-10 tranny, 3.70 gears 16X8" IROC wheels. 12" Corvette brakes on the way.
see dirty pics here of a car that gets driven http://community.webshots.com/user/novaderrik

Nova just hit the nail on the head.

4 bolt blocks just have a higher resale value.

------------------
Matt Jones
1969 Base Camaro
Vortec 355, Perf. RPM, Demon Carb., TH-400
All sheetmetal is NOS GM
See my UPDATED webpage at: http://www.geocities.com/compuboy007/ (Updated: 1/13/03)

..

[This message has been edited by camaroman7d (edited 01-28-2003).]

oops wrong topic

My book shows it's a 350cu in from 1980 to 1984 out of a passenger car.It usually states if it's a 4-bolt and this spec doesn't.Hope that helps. Can anyone explain why there are 2 and 4 bolt mains if there is no difference. http://www.camaros.net/forum/confused.gif

------------------
68 Camaro Coupe(restoring)
65 Pontiac Parisienne Convertible Summer Cruiser(Canadian version of Bonneville)

IF it helps, the suffix on the front pad is FRH.

I have heard the hardcore guys prefer the 2 bolt blocks. They can have them machined for 4 bolt splayed, and they are stronger due to the splay, and the thicker main webs.

Timberwolf,

I've got the same block and it turned out to be a 4-bolt, but that's because it was in a 1980 half-ton 4x4 pickup. What did your block come from?

I couldn't find any info on that FRH. I would compare it to mine but the pad on the 14010207 block I have is too far gone to read it.



------------------
Joe
1969 Camaro - The Hole-y Grail Project
HwyStar@Rochester.rr.com
HwyStar's Garage! (http://www.geocities.com/hwystarjoe/index.html)
1970 Malibu (http://home.rochester.rr.com/hwystar/page2.html)

Well, it came from a guys garage http://www.camaros.net/forum/smile.gif He thought it might have come from an 80 camaro he had, but wasn't sure. he also mentioned a nova, and who knows what else. In the daylight I'll get the rest of the numbers from the pad and see if there's anything else to go off of...

<BLOCKQUOTE>quote:</font><HR>Originally posted by HwyStarJoe:
Timberwolf,

I've got the same block and it turned out to be a 4-bolt, but that's because it was in a 1980 half-ton 4x4 pickup. What did your block come from?

I couldn't find any info on that FRH. I would compare it to mine but the pad on the 14010207 block I have is too far gone to read it.

<HR></BLOCKQUOTE>

Heck, if the sucker is in a garage, then just roll it over and drop the pan!! Worst you can be out is a new set of lower end gaskets to put it back together!! Then you will know for sure... pdq67

If it was out of a car, 99% of the time it will turn out to be a 2 bolt. In that 80 - 85 time frame its very hard to find 4 bolt blocks in anything, they are rare to find in anything smaller than a 1-1/2 ton P/U truck.

Just my opinion.

<BLOCKQUOTE>quote:</font><HR>Originally posted by novaderrik:
not 100% sure, but if it's all original and together, i THINK the 4 bolt engines got an 8" balancer.

<HR></BLOCKQUOTE>

I have the same situation. A '74 GMC truck 350 in my '69. According to all printed documents available it could be a 2 or 4 bolt. But is does have a 8" balancer. So is novaderrik on to something or are there other reasons for different size balancers.

------------------
Robert Johnson

'69 getting better every day... (every pay day) (http://www.angelfire.com/ab7/tempcarpage)
350ci 700r4 (2000 stall) 3.55 posi A/C PS PDB

Trucks typically got the bigger balancers. Trucks also typically got the 4 bolt blocks...especially after '73 or so. There is no external way to tell if they are a 2 or 4 bolt. Just a couple of weeks ago I yanked the pans off of 8 different sbc's at one of the local salvages...the guys there was telling me that if it has the 3 large numbers cast into the side of the block (freeze plug area) then they are a 4 bolt block. WRONG!!! 6 different 3970010 blocks...2 had the big numbers cast into the side of the block, but only 1 was a 4 bolt. One of the others was a 4 bolt also. Like Eric said, it is hard to find a 4 bolt block even in a truck from '80-85, unless it is at least a 3/4 ton.

FWIW, after I found a useable block, and had it machined, cam bearings and freeze plugs installed, and honed with torque plates, I could have got a brand new GM 4 bolt block with a standard bore (instead of .060 over) for the same price as just the machine work of my salvage yard motor. Something to think about.

Well, I opened it up today. Took the heads off. Ugh, weak 624 castings with 1.94/1.50 valves. I wasn't expecting much out of this thing...
Checked the cylinders...can't be more than .001-.002 ridge. Taper with a bore gauge is about .002. You can still see the crosshatching in the bores, and it has never been bored.
So far, not too bad. Low compression motor..dished pistons with 4 valve reliefs that stopped 1/4" below the deck.
Rolled it over and pulled the pan...surprised myself and the guy helping me to find 4 bolt mains. I really wasn't expecting it. For the record, it has the 8" balancer, but I didn't put much stock into that method.

One thing I did notice was that it appeared that the rods had been balanced. You could see mill marks on the pads on the big ends, and I could even tell the direction the mill/grinder was turning. There was quite a difference in height when comparing several different balancing pads on the rods.

Overall, looks like a decent motor. Not sure if I'll use it or sell it/trade it off. I'm eyeball deep in a 454 buildup at the moment.

2 and 4 bolt blocks had the 8 inch balancer. The 8 inch balancer IS NOT exclusive to a 4 bolt block.