I may have already asked this ? head question

[pedal2themetal45]

I can't seam to find any doner cars with a useable 200 around here I've checked the paper for about a month now.. You would think as big as this town is there would be something.. You know Muphy's law I'll find something just as I order the motor or when I get it running.
Will I gain anything by using a 65 200 head on my 61 170 block actualy I think the short block I would be ording is 64 or 65 170cu. and how much would I need to mill the 200 head to work on the 170 block or would I just need to get it cc and go from their?
Thanks all
Tim

 

[CZLN6]

Howdy Tim:

The '65 head will be a nice improvement over the '61 170 head. It will have bigger intake and exhaust valves at 1.69" and 1.38", and a larger intake tract volume. You'll need to do some upgradeing for long term durability- such as hardened valve seat inserts.

If you have it use the '65 carb too. It will be compatible with your Load-a-matic distributor and increase cfm from 150 to 185.

You can improve performance by boring out the 1.5" carb hole to 1.75", installing an exhaust port divider, adding a 3 angle valve job and back cutting the intakes with a 4 angle. Cleaning the top of the pistons and smoothing the chambers is worthwhile and cheap insurance against pre-ignition.

The '61 and '65 heads should both be close to 52 ccs for combustion chamber volume, but the new composite head gaskets are about .025" thicker than the OEM steel shim gaskets, which are no longer available. A mill cut of .025" to .035" will get you close to a true 9.2:1 ratio.

Isn't Boise at about 5,000 ft elevation too? If it is you can use a little more CR to compensate for the thin air. The '65 Autolite 1100 may be a bit rich too.

Adios, David

 

[pedal2themetal45]

Thanks David
I was thinking of upgrading the dizz to the DII system anyway.. I don't have the carb off the 65 but I do have a carb off a 72 pinto I don't remember what size the motor was or the number on the carb right now.. It kind of looks like a Weber type carb well this be OK to use over the stock carb from the 170. OH yes I beleve Boise is about 5,000ft.
Thanks
Tim