How much can I?
RavagePenguin
01-10-2005, 10:15 PM
How much can I bore a 301. Could I bore it to a 350 or could I go higher by dropping sleeves in.
MrPbody
01-11-2005, 09:20 AM
301 has a 4" bore. It can safely be bored to .040" over, but I doubt any further. .060" over pistons are available.
No, you can't "bore it to 350". 350 Chevy shares the same bore size. In fact, in some applications, we use 350 Chevy pistons. 301 has a 3" stroke, making 350 CID impossible, without going to a custom-made crankshaft. Since the block is so wimpy, it is not recommended you spend any serious money on 301, unless you're trying to qualify it in a specific class of racing (NHRA Stock or something like that), where rules REQUIRE 301.
It appears you need some automotive math, as well. You cannot "drop sleeves in" to increase displacement. Sleeving will generally make the bore smaller, reducing displacement.
To get a good running Pontiac, use a 400 block. It will "fit" where 301 lives, and produce a TON more power. I would suggest you buy Jim Hand's book "How to Build Max-performance Pontiac V8s", published by SA Designs. It is an up-to-date review of the Injun engine, as we use it today. Some very good info in there, and all of it is tried-and-true.
No, you can't "bore it to 350". 350 Chevy shares the same bore size. In fact, in some applications, we use 350 Chevy pistons. 301 has a 3" stroke, making 350 CID impossible, without going to a custom-made crankshaft. Since the block is so wimpy, it is not recommended you spend any serious money on 301, unless you're trying to qualify it in a specific class of racing (NHRA Stock or something like that), where rules REQUIRE 301.
It appears you need some automotive math, as well. You cannot "drop sleeves in" to increase displacement. Sleeving will generally make the bore smaller, reducing displacement.
To get a good running Pontiac, use a 400 block. It will "fit" where 301 lives, and produce a TON more power. I would suggest you buy Jim Hand's book "How to Build Max-performance Pontiac V8s", published by SA Designs. It is an up-to-date review of the Injun engine, as we use it today. Some very good info in there, and all of it is tried-and-true.
RavagePenguin
01-11-2005, 04:59 PM
Yeah I'm not that good in math. But thanks for the info. I'ill just keep the engine the way it is then. I can't really afford a new engine so do you know where I can get a used complete Pontiac engine. I'm looking for a 400-455 in size. Being stock is not a problem for me because I have a 75 T/A.
MrPbody
01-21-2005, 02:05 PM
In general, the only Pontiacs we see are cores. They're pretty old, so finding a runner is difficult.
Rduffner
02-22-2005, 12:04 AM
IF your looking for a 400 check out ebay.... normally i dont recommend buying engines off of it, however it sounds like a decent deal to me, im newer to the pontiac world, i would ask MrPbody he really knows his **** SEARCH FOR "PONTIAC 400" you should see it for 1200 buy it now.. the downside its a stock motor, but i can tell you it will be a night and day difference between the 2 stock motors
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