Cylinder head

Lawrie

Lawrie

Well-known member
After driving Richard from Anaheims Model A,I think I will put a higher comp head on mine,
And any thoughts on which one to use ,the 5.5-1 or the 6.1-1.
My eng has good babbit rods,insert mains,stock oiling system, a B grind cam and my A is a 28 open cab pickup.
Thanks Lawrie
 
You think you want a higher compression head. Let me ask you; why you think you want one, and what do you expect to get out of it then we can answer which one. The difference in price is about $50.00.
 
My A runs fine,it is stock,except for a 97 carb and the B cam,
But the idea of a bit more torque sounds OK.
I dont want a speedster or to travel at 60 mph(I have a couple of flathead V8s for that),
And I know that there is negatives with most modifications,
My A is super reliable and is used as everyday transport,it also does lots of trips away towing a small camper,hence the interest in more torque.
Thanks Lawrie
 
Who's got the picture of the Model A flat bed with two cars on back and towin' still another?

1930FordModelAA_700.jpg
 
The high compression head won't make your A run any faster or, if it does it won't be much.It will make it have more torque and be able to climb hills easier and pull loads with less damage and wear to the clutch and other driveline parts. You will get better fuel miledge or, I have found this so. I always claimed since I got my first one, this is the cheapest horsepower you can buy for the Model A engine.
 
I had a snyder 5.5 head on my 31 S/W (heavy car), but thought more hp and torque would be nice. I had an extra $300 floating around the shop that month. Orderend and installed the Snyder 6.1 head. After a couple head gasket issues she now runs fine. BUT i feel very little difference in the torque or hp between the 5.5 and the 6.1. If I had it to do over again I would have spent he $300 onsomething else and left the 5.5 on the engine.

The engine has insert rods and babbit mains, oversize valves, Weber carb. and is counterbalanced.
 
I also think the 5.5 will give the most bang for the buck and from what I've read the 6.0 to 1 doesn't offer all that much more power. Because the high compression head makes the engine run more efficient, you should expect a bit more fuel economy and the engine may run a bit cooler.

If Henry had just used a bit more compression, a counterweighted crank, and a good 4 speed with better ratios, we wouldn't need to be doing all these modifications now. Oh wait! :confused: I guess we don't really have to do these modifications, but it does help.:D;)
 
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I'm not sure why everyone needs more power.... My 29 Briggs is heavier than most and is 100% stock original. I have plenty of power. I drive 45-50 because thats where it seems to feel the best. It will go 60 if I want it to but 60 is too fast for a stock 80+ year old car. Don't have a bit of problem with hills, am going 40 or so at the top of most, thats good enough for me.
 
I you had your choice between pulling a 3 mile hill in second and a higher compression head and high gear, just to get home, you would understand.
 
I agree with Jerry. Its really more about driveability than added speed. A higher compression head is like the difference in day or night when it comes to driveability. They also run cooler and give better mpg. Its still a personal choice.
 
Thanks to all who replied,
The 5.5 seems the way I will go,
As I said I dont wont more speed just a bit more torque ,and this seems an easy way,
Lawrie
 
I have a 29 Fordor Leatherback that is a fairly heavy car. We live at 3500 feet in the Northern California Sierras. When we go on a tour we often climb another 500 to 3500 or more feet in elevation. With my car being the heaviest car and having a stock engine on the tours, I would begin to lag behind, the group would have to stop and wait a few minutes until I caught up more than once, as we pulled those mountains.

This spring after putting the Synder 5.5 on, with no other changes, I was easily able on a 5000ft climb, to keep up with no problems. You won't notice a significant difference when you take it out for test runs, but you will feel comfortable during the tours, because you won't be slowly left behind as you climb the hills.

The only problem I had with changing the head, was the removal of the old head. The old head had been in place over 20 years and the studs were locked in place and the head would only move slightly. I had to build the heavy metal plate removal tool, which is easy to do, but finding full threaded bolts to move the head 3-4 inches to clear the studs is a challenge.

I can't speak to the different compression ratios, but a 5.5 did exactly what I needed for my car.
 
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