Do-It-Yourself Radiator Upgrade for Series I E-Type


I'll be happy to provide whatever assistance I can. When you're all
done, I'd love to hear how it went, and how you like your new radiator.


I developed this upgrade for my own use, and I am offering it to others
as a courtesy only, and on a strictly AS-IS basis. USE THIS INFORMATION
STRICTLY AT YOUR OWN RISK!! I will accept absolutely no responsibility
or liability for anything that happens as a result of your use of the information
presented here.


Many E-type owners seem to have overheating problems with their cars,
particularly in warmer climates, like Florida and California. Although
conventional wisdom is this is just the way E-types are, I believe in most
cases, if you have trouble with overheating, there is an actual problem.
Ive talked to many E-type owners with totally stock cooling systems that
have no

problems whatsoever. 

In my case, my radiator was, as far as I know, original, but in very
poor condition, due to being parked for many years filled with just water.
It was clear I needed a new radiator, and its well known that aluminum
radiators can provide superior cooling. However, the cost for an exact
replacement aluminum radiator from the usual suspects was beyond my budget.

Rather than live with a cooling system that was marginal, I started
investigating other alternatives. In fairly short order, I found that high
quality aluminum radiators designed for Detroit V-8s were available from
a number of sources at a fraction of the cost of the exact replacement
ones. I did a little more research and discovered that several such radiators,
designed for GM

racing V-8s, were available for as little as $189, and several of these
appeared to be very close to the size of my original radiator.

I decided to risk the $189, and ordered one, hoping I could find a reasonable
way to adapt it to my 64 OTS. Much to my surprise, the job was much simpler,
and worked out much better than I ever dared hope. The entire installation,
including removing the old radiator, fabricating the new mounting brackets,
and installing the new radiator took less than two hours,

and cost less than $20. 

The performance is nothing less than amazing! I can now idle in 100F
heat without overheating! In fact, even at 105F, the temperature never
goes above the temperature at which the fan kicks in, which I currently
have set at ~80C. The second the fan comes on, the temperature gauge starts
to fall. Under more typical operating conditions, the fan virtually never
comes on!

Fabricating the brackets requires nothing more than a few bits of steel
stock, available from most hardware stores or home centers (Home Depot),
a hacksaw, and some very basic welding (steel only for the 3.8, some aluminum
welding required for the 4.2). None of the welds are visible, so if you
have access to an arc or gas welder, even if youre not very skilled, you

should be able to do an acceptable job.


Well, that depends. The bracket is designed to fit a Series I 3.8 car,
although I believe the same radiator and brackets would work with any series
4.2, with a little minor modification. In particular, to really do it right
would require having two fittings welded to the top right of the radiator
to accept the two additional hoses on the 4.2 radiator. I havent tried
this yet, so if youre interested, and not sure how to proceed, let me
know, and Ill try to help out. If you try it and find an approach that
works, also let me know, and Ill update this document so other can benefit
from your experience.


Refer to the drawing of the mounting brackets (click
). The brackets are fabricated from simple steel stock and hardware,
available from most hardware stores and home centers. Youll need:


  • 4 ft. of 2 wide x 1/8 thick mild steel stock, not galvanized
  • 1 ft. of ½ x ½ square mild steel tubing
  • 2 pcs. of 3/8-24 x 1- ½ bolts
  • 2 pcs. of 3/8-24 Nylock nuts
  • 2 pcs. of 3/8 fender washers
  • 2 pcs. of ¼-24 x ¾ bolts
  • 2 pcs. of ¼-20 hex nuts
  • 4 pcs. of ¼-20 x 2-1/2 bolts
  • 4 pcs. of ¼-20 Nylock nuts
  • 1 pc. high-pressure radiator cap (for new radiator)
  • 1 pc. 1/8 brass pipe plug (only required for Howe radiator)
  • 1 pc. 1-3/4 radiator hose with sharp ~90 degree bend (see text below)

The only tools needed are a hacksaw, drill, and any kind of welder. The
square tubes on the brackets are guides for the 2 bolts that fasten
the brackets to the mounting flanges of the radiator. The other hardware
duplicates the original mounting points for the stock radiator for a 3.8,
so that no modifications are required to the car.

For surface finish, on the brackets, once assembled you can paint them,
have them powder coated, chrome plated, or whatever you like.

The new radiator cap is used to cap off the filler neck on the new radiator.
For Series I cars, you will continue to use the filler on the header tank,
so just get a cap for the new radiator that is higher pressure than the
one on the header tank.

The 1/8 pipe plug is required to cap off the overflow tube connection
on the Howe radiator. It appears the overflow connection on the Griffin
is a hose connection, that can be capped with a short piece of plugged
hose. Of course, if the new radiator cap does its job, these plugs should
be unnecessary.

The lower outlet on these radiators is in a slightly different position,
and at a slightly different angle than the stock one. The radiator hose
mentioned above is required to make the connection between the lower radiator
connection and the water pump inlet hose. On my car, changing out the short
connector hose from the lower radiator fitting for one with a sharper bend
in it was enough to allow the connection to be made without any of the
hoses rubbing against the picture frame, sway bar, or steering rack.

On most cars, there is a short elbow which connects the lower radiator
fitting to a metal elbow tube. There is then another hose which makes
the connection from this tube to the water pump inlet. On my car, this
metal elbow was actually fabricated (by the restoration shop) out of a
section of a 1-3/4 EMT elbow. Some cars may have a single rubber hose
making the

entire run. If you have this, you may need to get the metal elbow to
be able to make the connection properly. It is also possible your existing
hose will be flexible enough to connect up without modification.

Whatever configuration your car has, youll probably need to search
through the hoses available at your local auto parts store and find a 1-3/4
hose with a tight ~90 degree bend somewhere in it. Youll then need to
cut out that section of the hose and discard the rest.


You have a choice of radiators, though I can only vouch for the fit
and operation of the particular one I used. I used one made by Howe. There
is also one made by Griffin that appears to me should fit and work just
as well, and would look more like the original. However, the bracket design
would probably require minor modifications to make the Griffin fit. If
you like the

Griffin, and want to give it a try, I can help in revising the design
to suit.

The best-priced source I found for either of these is Performance

There are nice pictures of both radiators on the web site. Both are
the same nominal size: 19 x 22 x 3. The part numbers are:

Howe: P/N 342B $189.95

Griffin: P/N 12X182 $199.95


Make sure you water pump and thermostat are in good condition, and
your fan is working properly. Rather than trusting the Otter switch, as
they seem to be rather unreliable, I bought an adjustable electronic fan
switch that senses temperature by means of a probe inserted between the
fins of the radiator core, adjacent to the inlet hose. I set the fan to
come on at ~82C, a

temperature that will only be reached under fairly extreme conditions.
This setup has worked extremely well for me, and has proven very reliable.


Fabricating the brackets and installing the radiator is pretty straight-forward,
if you are at all mechanically adept. Fabrication of the brackets does
not require any great skill or precision. Spot weld the tubes, 3/8 bolts
and ¼ nuts to the brackets, being sure to first grind any platingoff
the areas to be welded.

Once the brackets are fabricated, fasten them to the radiator using
the four two inch long ¼ bolts and Nylock nuts. Once the brackets
are attached, the radiator should go back in pretty much like the stock
one (at least for a 3.8) using the 3/8 Nylock nuts and fender washers
for the lower connection. Again, if youre doing this on a 4.2, Id like
to hear about any differences.

When re-assembling the hoses, make sure the lower hose does not contact
the picture frame, water pump belt, sway bar or steering rack.

After doing the install, drive the car for long enough to get it fully
up to temperature. After driving a while, re-tighten all the hose clamps.