170 head swap for 200?

[Anonymous]

I have a 63 170 in my comet now. The front exhaust port is pretty much ruined from rust and a cracked exhaust bolt mounting hole...on top. I also have a 69 200. What problems will I run into if I swap the 170 head for the 200? Will I drop compression? Will it just flow better? I just don't know these engines well enough. All help will be appreciated.
Wes

 

[rbohm]

8) http://fordsix.com/forum/viewtopic.php?t=1027

 

[Anonymous]

I have actually read that thread. It focuses on the 200 to 250. I guess I just need the valve size differences between the 63 170 and the 69 200. I don't want to pull the head off of the running car untill I know what I may or may not be doing.

 

[fordconvert]

Unless you know for 100% sure that your motor is an untouched original best bet is going to be to measure and CC things. Most of these engines were so popular and have been apart/rebuilt so many times by this point its hard to know what you are going to end up with. I have 3 heads 2 are supposed to be identical all are supposed to be close there is a 20 cc differnce between them. My motor has strange pistions in it so to get 8.5:1 I had to go with my orignal head that must be shaved down quite a bit to work with those pistions.

 

[mustang6]

I agree with everyone saying to cc: the chambers to compare what you have, I just wanted to add that I believe you will find that the 170 chambers are smaller, closed chambered. The larger 200/250 open chambers will take some head milling to get down to the same cc:s as your 170 chambers but it can be done.

 

[Anonymous]

I just went and bought another 62 parts car with a 170 in it. I will just have that head re done and use it.Thank you all for you're help.

 

[LEROY POLL]

HELLO GREYGHOST


.....I JUST READ YOUR POST TONIGHT FOR THE FIRST TIME. SORRY I DIDN'T READ IT SOONER.

.....I WENT THROUGH THIS HEAD THING ABOUT EIGHT YEARS AGO. WHAT I FOUND WAS THE 1970 MAV. 170 CU.IN. MOTOR WAS THE BEST HEAD TO GET. IT WAS THE BEST 170 HEAD FORD MADE.

.....IT HAS THE BIGGER VALVES, LARGER LOG,AND LARGE CARB. MOUNT. I WENT OUT AND FOUND ONE AND HAD IT WORKED OVER. I PUT IT ON MY 200 CU.IN. MOTOR AND WAS VERY PLEASED WITH IT. THIS HEAD DOES HAVE EVERYTHING YOU WOULD WANT TO UPGRADE WITHOUT ANY OTHER MODIFIATIONS. IF YOU CAN FIND ONE IT WOULD BE WORTH IT TO BUY. I JUST WISH I COULD HAVE TOLD YOU BEFORE YOU BOUGHT YOUR 1962 MOTOR.

LIVE IN GRACE

LEROY POLL

 

[wallaka]

HELLO GREYGHOST


.....I JUST READ YOUR POST TONIGHT FOR THE FIRST TIME. SORRY I DIDN'T READ IT SOONER.

.....I WENT THROUGH THIS HEAD THING ABOUT EIGHT YEARS AGO. WHAT I FOUND WAS THE 1970 MAV. 170 CU.IN. MOTOR WAS THE BEST HEAD TO GET. IT WAS THE BEST 170 HEAD FORD MADE.

.....IT HAS THE BIGGER VALVES, LARGER LOG,AND LARGE CARB. MOUNT. I WENT OUT AND FOUND ONE AND HAD IT WORKED OVER. I PUT IT ON MY 200 CU.IN. MOTOR AND WAS VERY PLEASED WITH IT. THIS HEAD DOES HAVE EVERYTHING YOU WOULD WANT TO UPGRADE WITHOUT ANY OTHER MODIFIATIONS. IF YOU CAN FIND ONE IT WOULD BE WORTH IT TO BUY. I JUST WISH I COULD HAVE TOLD YOU BEFORE YOU BOUGHT YOUR 1962 MOTOR.

LIVE IN GRACE

LEROY POLL

It was probably the exact same one that the 200 and 250 had.

 

[mustang6]

It was probably the exact same one that the 200 and 250 had.

Not exactly, as you can see from the pics below of this early 70's 170 head, it has most of the later features Leroy indicates (I don't think it has quite as large valves as the late 200/250 heads) but still has the smaller closed chambers to keep compression up for the 170.

Compare that to the chamber shape and size of this 200/250 head from the same era. Even though I milled it prior to cc:ing it in these pictures, you can still clearly see it has the open combustion chambers.

Closed chambers are generally regarded as providing better swirl and combustion, but the late 70's 200/250 heads have slightly larger intake valves than even the late model 170 head.