MTFCA Forum

If I am buying both a new hood and radiator for my 25TT, do I care if its High hood or low hood?
My firewall is 28” wide x 21 1/2” tall not counting the little bump for the radiator rod.
Availability is more important to me than authenticity.

The firewall determines the needed hood...the hood determines the needed radiator.

There are significant dimensional differences between the early black stuff, the late black stuff.

If your firewall is true '25, then you are going to need a high hood and a high radiator, or nothing will ever even come close. The 28" would say HIGH hood...the low hood is only like 24 or so.

Here’s an earlier post that can help you tell the differences. https://www.mtfca.com/discus/messages/29/38157.html

The high hood would look better on a TT, in my opinion, and if the high radiator has increased cooling capacity, that would be a definite plus.

Steve Jelf wrote: ↑

Thu Dec 15, 2022 11:18 am

The low steel firewall was used only in 1923.
The easiest way to identify high or low firewalls:

Low: large wiring hole under the terminal block.

High: large wiring hole above the terminal block.

Remember that the low steel fire wall was sold as "the" replacement fire wall for 17-23 after their introduction in 23.

speedytinc wrote: ↑

Thu Dec 15, 2022 12:11 pm

Remember that the low steel fire wall was sold as "the" replacement fire wall for 17-23 after their introduction in 23.

You sure about that? Changing from a wood to steel firewall requires different firewall to frame brackets and a different hood rod at minimum.

I believe there was a paragraph in the Ford Service Bulletins regarding utilizing a (4) spacer on the firewall brackets to prevent having to replace the brackets for the wood to steel changeover.

Early on before the frame to firewall brackets were modified, when the steel firewall was used on a 17-23 chassis, the upper caps for radiator mounts were used as spacers. While the wood firewall to radiator rod used might work with the low steel firewall, the 1927 parts book does list it with a new parts number for 1923, 3932B. That could simply be that the threaded part at the firewall end had less threads as the overall length should be the same as earlier cars.

If your going to get a radiator in the long run it’s best to buy a new one. If you have a high radiator 24-27 already you can save some money if you put a new flat tube core for it and if you can find a shop that will do it! The purist would want a round tube but a flat tube cools better. If yours did come out with a flat tube but even if you have one age eventually gets to a radiator. And yes you find some decent or good looking originals. BUT if they were good they wouldn’t be at a swap meet. Don’t let them fool you.
Occasionally there is a good one in the classifieds but they sell pretty quick.

Another way to distinguish a high dash (firewall) from a low dash is by counting the coil box terminal holes. The low dash has 10 holes for 10 coil box terminals. The high dash only has nine. The coil box battery terminal was eliminated (along with the switch on the coil box) when the high dash was introduced.

Respectfully submitted,

Trent Boggess