Almost all Chevy 4 bolt main blocks were installed in trucks. That must mean something....I don't know what....
That's what I always thought. In the salvage yards, if a small block was taken from a truck.. the oil pan was chopped open for a look see... they brought bigger $$$ from the recyclers. Bob
I have a BB chevy OT car that I have run for 10 years now that is a two bolt. I beat the **** out of it when we play. So far no problems, but I will admit that four bolt thing has crossed my mind quite a few times.
I had a '66 vintage 396 in a Nova stock car that got the **** hammered out of it for 2 years, sometimes 2 nites a week at local tracks. Never a peep out of it with 60# of oil pressure all the time. It finally gave up a main bearing, but was nice enough to give me a warning rattle when I fired it up for the main. This was a 2-bolt motor. Bob
Yes, there was fretting. I kept this short, due to the nature of the question, I posted on this same engine on another thread a year ago, in more detail. No signs of detonation were present (I know that will be the next question) and it was a 427 built from a 454 block with a 396 crank and TRW L-72 pistons. It needed a slug of mallory metal to balance, N/A motor with small bolt rods. Big roller, 12/1 oval port heads, single dominator 7000 rpm, so not a real extreme amount of rpm. Several mains were down to the copper on one side on the bottom insert, top of the insert at the other end of the same insert, looked good otherwise. The journals in the block still measured straight, didnt need an align bore. I came to the conclusion that either the block or the crank was twisting along its long axis, the main caps were dancing around, and that we were approaching the structural limitations of that block with steel rods. Some may remember, I re-staked the main caps with a punch changed the bearings, and ran it a little longer, then sold it to some guy that was convinced the short block was "trick of the week" because of the numbers the car was running.
It's easy straightening out a crank .. Just need a good indicator and mag base.. And a "Dead Blow" hammer... I've done it a few times before...
Your not following me Dueces. Things were moving around when the engine was under load, either the block, the main caps the crank, or a combination of all three. The crank and main journals in the block were straight when measured. One other thing I forgot, that should be mentioned, the block did have two sleeves in it.
No rattles yet, but I can't hear **** when she's running and I really hope I don't. Love that old gas guzzling bomb.
I had just ran my heat race, finished towards the front and basically standing on it for 10 laps. No noise, no signs of trouble. Fire it up for the main... rapppppppp. Still had awesome oil pressure. Lined up for the main, took the green and pulled it in to get last place $25. Bob
Straightening depends on how and where the crank is bent. Although it looks brutal, but pros often peen the journal fillets to straighten a crank.
Over here, all our recycler magazines advertise "4 Volt mains" we don't have "Camero's" though , we have something worse than that. A Camira [ a real model by GM ], I'll let the Aussie members explain what this monstrousity is
Two bolt Chevy is fine for the street. Add some hard studs and then go racing! Yes! you can break anything if you work at it hard enough.
The Jalopy Journal
