327's
doctorheat
08-27-2008, 10:20 AM
Someone told me that 327's are known for blowing, but I figure I just build it right, it shouldnt have any problems. then he said it doesnt matter, it'll still blow... is this guy just an idiot?? (which is what im goin with)
MT-2500
08-27-2008, 12:34 PM
Not to get into any pissing matches.
Back in the 283 and 327 days the 283 lived a lot longer than a 327.
A lot of 327 engines went before and after 50K.
Rings and pistons was a weak spot.
The old 283 would run forever with proper car.
The 327 had a lot of HP built in them.
They would blow the doors off a ford and give the cry big engines a run for there money.
The weakest thing was the pistons would melt down from extra HP and compression or overwinding.
If you are going to build one go the best pistons you can get.
Have fun and enjoy it.
Good Luck
MT
Back in the 283 and 327 days the 283 lived a lot longer than a 327.
A lot of 327 engines went before and after 50K.
Rings and pistons was a weak spot.
The old 283 would run forever with proper car.
The 327 had a lot of HP built in them.
They would blow the doors off a ford and give the cry big engines a run for there money.
The weakest thing was the pistons would melt down from extra HP and compression or overwinding.
If you are going to build one go the best pistons you can get.
Have fun and enjoy it.
Good Luck
MT
bobss396
08-27-2008, 01:07 PM
The pistons were known for having the ring lands breaking off of them. Aside from that, I've had a few that were scorchers and turned some great RPMs. If I were to do another one up, I'd look for a '68 or '69 as they had the full PCV system in them. The older ones had that funky smog canister under the intake manifold.
Bob
Bob
MrPbody
08-27-2008, 02:49 PM
327s were notorious for blowing...the doors off the competition! Parametrically speaking, one of the best smaller cubed engines of the '60s. They would indeed, rev to "the moon". The piston failures were generally those that would either use a 300 (or less) HP version with too large a cam, too big a carb and not enough fuel. At 7,500 RPM, it doesn't take long for a cast piston to melt, literally, and a "lean" condition will make that happen. The 325 and "bigger" versions had forgings and could take it a bit better. The older stuff used TRW forgings, which are TANKS by today's standards.
The later ones were "large journal" blocks (350 blocks, 307 cranks). There were very few of these with a forged crank OR forged pistons, and those were in Corvettes. The small journal version is the one that got 327 the reputation as "the little engine that COULD".
No, not traditionally known for "blowing". Actually, one of the tougher engines of its era if kept in good tune. "Kept in good tune" goes for ALL engines. Even the best ones can't take detonation, leaning out or other kinds of abuse.
This is coming from a guy that builds Pontiacs, which are often said to be weak and prone to "blowing". Only if built like a 327... Argh! Argh! Humor...
Build your little mouse motor and be proud of it!
Jim
The later ones were "large journal" blocks (350 blocks, 307 cranks). There were very few of these with a forged crank OR forged pistons, and those were in Corvettes. The small journal version is the one that got 327 the reputation as "the little engine that COULD".
No, not traditionally known for "blowing". Actually, one of the tougher engines of its era if kept in good tune. "Kept in good tune" goes for ALL engines. Even the best ones can't take detonation, leaning out or other kinds of abuse.
This is coming from a guy that builds Pontiacs, which are often said to be weak and prone to "blowing". Only if built like a 327... Argh! Argh! Humor...
Build your little mouse motor and be proud of it!
Jim
doctorheat
08-27-2008, 06:19 PM
Ok, thats pretty much what I figured, Thanks for your help.
And another question, my friend has a 305 in her truck, and its due for an overhaul, is it worth it to build it up(cam, valvetrain, intake, carb, headers, home port/polish) or would we just be wasting our time? I've heard mixed things about this one...
(And I'm not new to building engines, just new to Chevy's...)
And another question, my friend has a 305 in her truck, and its due for an overhaul, is it worth it to build it up(cam, valvetrain, intake, carb, headers, home port/polish) or would we just be wasting our time? I've heard mixed things about this one...
(And I'm not new to building engines, just new to Chevy's...)
silicon212
08-27-2008, 08:02 PM
Ok, thats pretty much what I figured, Thanks for your help.
And another question, my friend has a 305 in her truck, and its due for an overhaul, is it worth it to build it up(cam, valvetrain, intake, carb, headers, home port/polish) or would we just be wasting our time? I've heard mixed things about this one...
(And I'm not new to building engines, just new to Chevy's...)
For power, if you're starting from ground level (as in rebuilding the engine), go with a 350 block as they are cheap, plentiful and yield a lot of power for their size. In fact, the 350 is a 327 that has been stroked .23". A 305 can be built to make power, but the 350 is easier to get power out of due to bore size (meaning max valve diameter). A 305 can be used with factory heads that have 1.84 intakes - 1.88 max without extensive reworking. Using 1.94s may require notching the block for clearance if you're not running the right heads, and 2.02s are completely out of the question. Even on heads that will allow 1.94 intake valves on the 305, intake valve shrouding can be a problem.
You have none of those issues on a 350, short of shrouding on certain heads w/2.02 intake valves.
And another question, my friend has a 305 in her truck, and its due for an overhaul, is it worth it to build it up(cam, valvetrain, intake, carb, headers, home port/polish) or would we just be wasting our time? I've heard mixed things about this one...
(And I'm not new to building engines, just new to Chevy's...)
For power, if you're starting from ground level (as in rebuilding the engine), go with a 350 block as they are cheap, plentiful and yield a lot of power for their size. In fact, the 350 is a 327 that has been stroked .23". A 305 can be built to make power, but the 350 is easier to get power out of due to bore size (meaning max valve diameter). A 305 can be used with factory heads that have 1.84 intakes - 1.88 max without extensive reworking. Using 1.94s may require notching the block for clearance if you're not running the right heads, and 2.02s are completely out of the question. Even on heads that will allow 1.94 intake valves on the 305, intake valve shrouding can be a problem.
You have none of those issues on a 350, short of shrouding on certain heads w/2.02 intake valves.
MrPbody
08-28-2008, 05:51 PM
For a truck, the 305 isn't a BAD choice. It can be made to be very torquey. Silicon is absolutely correct about valve sizes. Using anything larger than the 1.84 valve results in the intake mixture "slamming" into the cylinder wall as it comes in. Though old-school methods included "notching" the block, we've found it flows better if left alone. We HAVE used 305 HO heads (601 casting) for "cheap" 350 performance heads by adding the 1.94s and 1.6 exhaust valves. It will yield a desirable compression ratio for race gas on a 350 block. VERY strong torque in the mid-range.
Use a "torque" or "RV" cam in that 305. Fuel economy will improve significantly. We recommend Comp 255DEH (grind number). Snappy, smooth idle, maybe a 20% improvement in fuel economy and still enough torque to pull a load under 4,500 RPM. That cam is known to work with either carbs or throttle-body injectors.
Jim
Use a "torque" or "RV" cam in that 305. Fuel economy will improve significantly. We recommend Comp 255DEH (grind number). Snappy, smooth idle, maybe a 20% improvement in fuel economy and still enough torque to pull a load under 4,500 RPM. That cam is known to work with either carbs or throttle-body injectors.
Jim
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