The Rub:
Well, fellas, I've gotten a top end together that I will swap onto a stock or stockish block, probably this winter. My car's running great, and I'm not in a hurry. So, I figured I'd use the opportunity to try to find a budget-friendly upgrade. I know the mexican and older '60s era blocks had thicker main webbing. The old rotating assemblies up until '82'-83 were also 28oz instead of 50oz, which should be better for higher RPM.
I could refresh the stock block in Black Jack, but it'd be nicer if 1) I can swap complete motors in a couple days and have a running car again quickly, & 2) get a better shortblock at the same time.
So, that said, I would appreciate validation of my understanding and/or advice. I believe that pretty much any '60s era 302 block up through about '74 (exact year?) is considered an "early" 302 and has better quality iron & the thicker main webs than the later 70s & 80s blocks.
How to ID (quickly googled):
- In general:
1. mexican blocks:
a. “HECHO-EN MEXICO” stamp visible if block is disassembled
b. two iron knob-like protrusions just below each head on the front of the engine casting. The tips are circular and slightly larger than a half dollar. The left knob is not entirely circular, but usually has a flat bottom.
c. Came in late 60s, early 70s Rancheros and Torinos, vans and Trucks
2. 'Early' 302: Aside from the part numbers...?
3. Original Boss (yeah, right, but a man can dream): DOZE-6015-B stamped. 4-bolt mains.
4. 289 standard & "Hi-Po"...
5. Any others I should be considering?
Conversion Considerations:
In terms of converting them to work in place of an HO roller block, what adjustments are required?
- Early block head bolts are fully blind and don't need sealant on the head bolts
- Non-roller blocks require either link bar lifters or drilling and tapping the lifter valley to accept the stock spider and lifter tie-bars (M-6253-A50). Any adjustment to lifter bores or anything else I need to convert? Will it accept the same link bar lifters as a stock HO block? Diameter, height, etc...
- Aren't some of them 162 tooth flywheels instead of 157?
- I'm assuming they use the same engine mounts, and believe I've heard the stock bellhousing bolts right up. Correct?
-What else am I missing?
The smart buy:
What would you expect to pay, and whats the best way to minimize the chance of getting a bad motor? As a quick observation, there's a 302 from a '74 F100 listed near me for $450.
The ideal would be to get a chance to see the car running and then pulled after the purchase agreement. I think generally, I plan to stay away from anything that's been hot-rodded before me. So many folks are willing to lie about their 347 that's really a 302. I've read other stories from builders that said when someone mentions a problem, it is in their experience never the problem. It's always worse. Still is there any advice on basic checks/inspection one can do to help your chances of not being taken advantage of?
Well, fellas, I've gotten a top end together that I will swap onto a stock or stockish block, probably this winter. My car's running great, and I'm not in a hurry. So, I figured I'd use the opportunity to try to find a budget-friendly upgrade. I know the mexican and older '60s era blocks had thicker main webbing. The old rotating assemblies up until '82'-83 were also 28oz instead of 50oz, which should be better for higher RPM.
I could refresh the stock block in Black Jack, but it'd be nicer if 1) I can swap complete motors in a couple days and have a running car again quickly, & 2) get a better shortblock at the same time.
So, that said, I would appreciate validation of my understanding and/or advice. I believe that pretty much any '60s era 302 block up through about '74 (exact year?) is considered an "early" 302 and has better quality iron & the thicker main webs than the later 70s & 80s blocks.
How to ID (quickly googled):
- In general:
1. mexican blocks:
a. “HECHO-EN MEXICO” stamp visible if block is disassembled
b. two iron knob-like protrusions just below each head on the front of the engine casting. The tips are circular and slightly larger than a half dollar. The left knob is not entirely circular, but usually has a flat bottom.
c. Came in late 60s, early 70s Rancheros and Torinos, vans and Trucks
2. 'Early' 302: Aside from the part numbers...?
3. Original Boss (yeah, right, but a man can dream): DOZE-6015-B stamped. 4-bolt mains.
4. 289 standard & "Hi-Po"...
5. Any others I should be considering?
Conversion Considerations:
In terms of converting them to work in place of an HO roller block, what adjustments are required?
- Early block head bolts are fully blind and don't need sealant on the head bolts
- Non-roller blocks require either link bar lifters or drilling and tapping the lifter valley to accept the stock spider and lifter tie-bars (M-6253-A50). Any adjustment to lifter bores or anything else I need to convert? Will it accept the same link bar lifters as a stock HO block? Diameter, height, etc...
- Aren't some of them 162 tooth flywheels instead of 157?
- I'm assuming they use the same engine mounts, and believe I've heard the stock bellhousing bolts right up. Correct?
-What else am I missing?
The smart buy:
What would you expect to pay, and whats the best way to minimize the chance of getting a bad motor? As a quick observation, there's a 302 from a '74 F100 listed near me for $450.
The ideal would be to get a chance to see the car running and then pulled after the purchase agreement. I think generally, I plan to stay away from anything that's been hot-rodded before me. So many folks are willing to lie about their 347 that's really a 302. I've read other stories from builders that said when someone mentions a problem, it is in their experience never the problem. It's always worse. Still is there any advice on basic checks/inspection one can do to help your chances of not being taken advantage of?
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