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Topic Review (Newest First)
11-18-2012 09:45 AM
Jim Rockford any head larger than 58cc will be useless on a 305. just stick with a good set of tpi 305 heads and you will be fine.
11-17-2012 02:26 PM
spinn Yes i have them. There yours if you want to pick them up. If you can figure out how to sent iron heads pm me with ideas.

Had to find the thread again. Not cracked and stored inside.
11-09-2012 07:02 PM
allansmith859 Ok thanks for the input. Just curious. Im not doing this cause I dont want to waist these heads on a 305 but how would the 305 react to vortec heads (906) and that cam I listed above. Both heads are 64 cc but of course the 906's flow alot better. Would it be worth doing that. I have two pairs of vortecs but also have two 350 blocks I am putting them on and experimenting with the two. Curious how they would do on a 305 with that cam. Nothing else.
11-09-2012 06:16 PM
spinn The 305 and like engines are non interference fit. It would take gross amounts of lift and a catastrophic rotational event for the piston to touch the valve.
11-08-2012 07:18 PM
allansmith859 What if I ported those heads and put the cam in the 305. Do you all think that it would be ok for a daily driver. Also I have flat top pistons. Do I need to worry about a valve hitting the piston
11-08-2012 01:41 PM
spinn THat 420/442 cam is one of the best designs to replace the stock cam. It gives you more power and torque while sacrificing nothing. I have used it many times. It makes a nice driver.
11-08-2012 12:59 PM
allansmith859 Is it because to much compression. Is there any thing I can do to help it perform better. I have a jegs cam shaft. Lift: .420"/.442 Adv. Duration: 262/272 RPM Range: 1500-4000 sittin in the basement. Would that help it.
11-08-2012 12:32 PM
E.Furgal it'll run.. but you'll be happer with 305 heads..
11-08-2012 12:15 PM
allansmith859 So you are saying I cant use these heads for a stock 305 engine that has normal power.
11-07-2012 09:08 PM
spinn You want a set of 305 58cc 1.84/1.50 valves 1985 heads that hold water? If i can find them Pm me. You pay shipping.
11-07-2012 12:53 PM
allansmith859 How do I do a leak down test??? What about puttin these heads on this engine if everythings good?? (14101083)
11-07-2012 12:50 PM
Originally Posted by allansmith859 View Post
I have a 305 sbc in the basement and I was wondering, can I use a compression gauge and turn the engine over to determine if the rings are still good and that its got the right comp.. The bottom end is still in the block. i have a pair of good truck heads I can put on the block. Can I do it this way or does it have to be actually hooked up in a vehicle.
Don't see why this wouldn't give some sign of ring quality. The engine is probably pretty dry I'd put some lube on the cylinder walls before putting the heads on. A leakdown test may prove to provide more valuable information than a compression test if you've got a compressor you can use to presurize the cylinders.

11-07-2012 12:42 PM
allansmith859 The cylinder walls look great. There is a very little amount of surface rust that has appeard in two of the cylinders at the very top but I can clean that off. There is no lip at all they look very good. If I put these cylinder heads on this block which is bored .060 over with flat top pistons (head # 14101083). Would it be a good little street motor depending on cam choice and other applications??
11-07-2012 10:38 AM
allansmith859 OK Im getting confused. Im trying to see if I can use this 305 engine. Its the block and rotating assembly. The guy who had it said HE THOUGHT one of the rings was bad cause of a little smoke out the exhaust. That could be from a valve seal. I was asking if I could just bolt ANY heads on and take a guage, screw it into the spark plug hole and turn the engine over and see what it reads for every cylinder. If I do that what can I learn about every cylinder.
11-07-2012 09:22 AM
spinn A cranking compression test is good with the carb removed or wide open.

A Cylnder leak down of each cylinder will get more in depth analysis if you find the location of the leaking air.

The oil pump output pressure belive it or not, is a excellent indicator of remaining engine life.

If the heads are off flip them over and fill the combustion chamber with water. The shut valves should retain the water pool in the chamber.
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