Low Head High Head?
Forum rules
If you need help logging in, or have question about how something works, use the Support forum located here Support Forum
Complete set of Forum Rules Forum Rules
If you need help logging in, or have question about how something works, use the Support forum located here Support Forum
Complete set of Forum Rules Forum Rules
-
Topic author - Posts: 11
- Joined: Tue Jan 15, 2019 8:51 pm
- First Name: Darvin
- Last Name: Jahnke
- Location: mn
Low Head High Head?
Not. new to old cars but new to Model Ts My question is what is the difference between a low head and a high head? Thanks
-
- Posts: 219
- Joined: Sat Jan 19, 2019 9:05 am
- First Name: Ryan
- Last Name: Snellen
- * REQUIRED* Type and Year of Model Ts owned: 1912, 1919, 20's FrankenT
- Location: Nashville
- Board Member Since: 2017
Re: Low Head High Head?
One is desirable (the low head), the other you donate keep in a jon boat as an anchor.
The low head gives more compression... the amount, someone else with more expertise may be able to answer that.
The noticeable difference is the water neck is taller. If you don't have much experience, the noticeable giveaway is looking at the passenger side water outlet threads. The deck plane where the head bolts mates to the head is flush to the water inlet threads. The low head you'll have a ~3/8 gap.
The low heads are vulnerable to cracking mostly along the neck. If purchasing a low head anywhere, inspect extremely close. I've also seen them crack on the drivers side.
Value depends on the markings or lack of; and condition of course.
I believe the high heads can be milled 125 thou. and will match a low head. Correct?
The low head gives more compression... the amount, someone else with more expertise may be able to answer that.
The noticeable difference is the water neck is taller. If you don't have much experience, the noticeable giveaway is looking at the passenger side water outlet threads. The deck plane where the head bolts mates to the head is flush to the water inlet threads. The low head you'll have a ~3/8 gap.
The low heads are vulnerable to cracking mostly along the neck. If purchasing a low head anywhere, inspect extremely close. I've also seen them crack on the drivers side.
Value depends on the markings or lack of; and condition of course.
I believe the high heads can be milled 125 thou. and will match a low head. Correct?
-
- Posts: 4094
- Joined: Tue Jan 08, 2019 1:39 pm
- First Name: Norman
- Last Name: Kling
- Location: Alpine California
Re: Low Head High Head?
The low head was used on the earlier cars, but at the outset of WW 1 the quality of fuel was poorer and the company lowered the compression to keep the engine from knocking. The high head actually has more coolant capacity but it does have lower compression. Please do not cs said. Do not use the high head for a boat anchor. It works very well and if you want to raise compression there are high compression after market heads available from the parts vendors. Many people want the head to match the year model of their car, and because so many later cars have used low heads, they make them more rare and harder to find for the cars which actually came with them. Same thing applies to the 26-27 wire wheels. Those wheels were only used by the manufacturer for those two years and even then not all the cars had the wire wheels and hubs. Many speedster owners have used the later wheels making them more rare and raising the price of those too.
Anyway, I have spoken my opinion. Yours might be different.
Anyway, I have spoken my opinion. Yours might be different.
-
- Posts: 5256
- Joined: Sun Jan 06, 2019 7:21 pm
- First Name: Allan
- Last Name: Bennett
- * REQUIRED* Type and Year of Model Ts owned: 1912 van, 1917 shooting brake, 1929 roadster buckboard, 1924 tourer, 1925 barn find buckboard, 1925 D &F wide body roadster, 1927LHD Tudor sedan.
- Location: Gawler, Australia
Re: Low Head High Head?
If you are looking for a difference to identify which is which, check out the combustion chambers. A low, [earlier] head will have pronounced rim around the spark plug hole, whereas the later high head appears as though they just drilled a hole and tapped it with thread.
Hope this helps.
Allan from down under.
Hope this helps.
Allan from down under.
-
- Posts: 1302
- Joined: Mon Jan 07, 2019 2:42 pm
- First Name: Frank
- Last Name: van Ekeren
- * REQUIRED* Type and Year of Model Ts owned: 1916 touring, 1916 pick-up, 1924 coupe, 1926 touring, 1927 touring
- Location: Rosedale Vic Australia
Re: Low Head High Head?
Man! you all made it hard for him, it's simple, the low head is 2" tall at the head bolts and the high head is 2-1/2" tall at the bolts.
-
- Posts: 9
- Joined: Wed Jan 16, 2019 12:12 am
- First Name: Michael
- Last Name: Dalessandro
- * REQUIRED* Type and Year of Model Ts owned: 1920 Touring
- Location: Detroit
- MTFCA Number: 50102
- Board Member Since: 2016
Re: Low Head High Head?
Lots of info can be found in previous posts on the old forum. Best way to find them is through a Google search.
https://www.google.com/search?q=mtfca+low+vs+high+head
https://www.google.com/search?q=mtfca+low+vs+high+head
-
- Posts: 5459
- Joined: Tue Jan 08, 2019 4:56 pm
- First Name: Frank
- Last Name: Brandi
- * REQUIRED* Type and Year of Model Ts owned: Speedster (1919 w 1926)
- Location: Moline IL
- Board Member Since: 2018
Re: Low Head High Head?
Found a picture
The past is a great place and I don't want to erase it or to regret it, but I don't want to be its prisoner either.
Mick Jagger
Mick Jagger
-
Topic author - Posts: 11
- Joined: Tue Jan 15, 2019 8:51 pm
- First Name: Darvin
- Last Name: Jahnke
- Location: mn
Re: Low Head High Head?
Thank you all for your replies. Now I know.