Go Back   The Ford Barn > General Discussion > Early V8 (1932-53)

Sponsored Links (Register now to hide all advertisements)

Reply
 
Thread Tools Display Modes
Old 01-18-2020, 12:46 PM   #1
westienz
Junior Member
 
westienz's Avatar
 
Join Date: Oct 2019
Location: Auckland
Posts: 10
Default 1936 pickup changing motor to a mercury motor

Thinking of changing my standard 21 stud
to a mercury motor
I have heard there is a big difference in performance
Has anyone done this replaced with a mercury motor and which motor is it ?
How much difference
Thanks for your help
westienz is offline   Reply With Quote
Old 01-18-2020, 02:37 PM   #2
JSeery
Senior Member
 
JSeery's Avatar
 
Join Date: Nov 2012
Location: Wichita KS
Posts: 16,095
Default Re: 1936 pickup changing motor to a mercury motor

What year(s) Mercury are you considering? Believe the earlier Mercury blocks had a larger bore and then later a longer stroke. Nothing really magic about a Mercury vs Ford engine, you can bore out a Ford to the same size as the Mercury and/or add a 4 inch Mercury crank to a Ford engine (some years of Ford blocks are easy to modify than others).

VanPelts site provides some basic engine information:

21 Stud: http://www.vanpeltsales.com/FH_web/f...cs-85early.htm
24 Stud: http://www.vanpeltsales.com/FH_web/f...85to100mid.htm
Later Model: http://www.vanpeltsales.com/FH_web/f...0to125late.htm

I would look for at least a 24 stud engine.
JSeery is offline   Reply With Quote
Sponsored Links (Register now to hide all advertisements)
Old 01-18-2020, 05:29 PM   #3
rotorwrench
Senior Member
 
rotorwrench's Avatar
 
Join Date: Jun 2010
Location: San Antonio, Texas
Posts: 12,989
Default Re: 1936 pickup changing motor to a mercury motor

The 99A was 239 but the 8CM is 255. I've seen one old 21-stud that was sleeved for 3 3/16" pistons and machined to take the 8CM crankshaft. It was a lot of work but they had a motor for a 35 ford that "looked" original and ran the whole Great American Race with no major problems. I bet it cost a fortune though.

If I was going to try and use the 8CM motor in a 36, I'd change all the frontal components over to the early style frontal accessories so that I could use a generator fan. That would be less work but it would require special build up of the engine to include an early type cam so the cam gear thrust would be correct for a crab type distributor. it's still a fair amount of work but mostly bolt on. The late to early motor adapters would have to be used to fit the engine mounts. I think Bob Drake still carries those. The 49 through early 51 Merc flywheel and clutch will work with the early 3-speed transmissions.
rotorwrench is offline   Reply With Quote
Old 01-18-2020, 05:43 PM   #4
Brian
Senior Member
 
Brian's Avatar
 
Join Date: May 2010
Location: Masterton, New Zealand
Posts: 3,167
Default Re: 1936 pickup changing motor to a mercury motor

The late to early motor adapters would have to be used to fit the engine mounts


Actually...no adapters required, just run the truck pumps. This pertains to 8BA series
__________________
Unfortunately, two half wits don't make a whole wit!
Brian is offline   Reply With Quote
Old 01-18-2020, 05:44 PM   #5
Brian
Senior Member
 
Brian's Avatar
 
Join Date: May 2010
Location: Masterton, New Zealand
Posts: 3,167
Default Re: 1936 pickup changing motor to a mercury motor

Westie...nothing wrong with a 21 stud.
__________________
Unfortunately, two half wits don't make a whole wit!
Brian is offline   Reply With Quote
Old 01-18-2020, 05:52 PM   #6
tubman
Senior Member
 
tubman's Avatar
 
Join Date: Dec 2013
Location: Minnesota, Florida Keys
Posts: 8,013
Default Re: 1936 pickup changing motor to a mercury motor

Sponsored Links (Register now to hide all advertisements)
As to any increase in performance, the engine originally in the vehicle was rated from the factory at 85 HP. If you were to install a '52-'53 Mercury engine (rated from the factory at 125 HP) you would have almost a 50% increase in power. Other Mercury engines through the years were rated at 95, 100, and 110 HP.
tubman is offline   Reply With Quote
Old 01-18-2020, 06:45 PM   #7
KiWinUS
Senior Member
 
KiWinUS's Avatar
 
Join Date: May 2010
Location: Charlotte NC KiWi-L100 available here
Posts: 2,443
Default Re: 1936 pickup changing motor to a mercury motor

I have a 36 pickup with a late merc engine. I purchased it this way & had been sitting in barn for 36 years before I purchased it a few years ago. I have not worked on it yet. Will try to get some pics of engine tomorrow. Cheers
Tony
KiWinUS is offline   Reply With Quote
Old 01-18-2020, 10:59 PM   #8
Brian
Senior Member
 
Brian's Avatar
 
Join Date: May 2010
Location: Masterton, New Zealand
Posts: 3,167
Default Re: 1936 pickup changing motor to a mercury motor

Westie, ANY flathead you build/buy/ fit into your truck will cost $$$$. There's an old saying that with flatheads you'll never spend so much money to go so slow! Sure, you can fit a much larger displacement engine, but then how are your brakes going to handle?
I've got a 35 sedan, had the old thing forever. It is my testbed...Had numerous different engine combo's in it over the years, ranging from 221 to 284. I much prefer the smaller displacement engines in an early Ford...the general opinion, the info you'll gather from the internet, is that 221's are rubbish, the later engines are far superior, there's no substitute for cubic inches, etc.
Try this concept; change out your existing 4.11 ratio diff to a 3.78.
Throw away your nice white wall cross plies, and fit a set of radials.

Fit aluminum heads.
Fit twin carb intake
You'll have a nice driving truck.
Enjoy it for what it is.
__________________
Unfortunately, two half wits don't make a whole wit!
Brian is offline   Reply With Quote
Old 01-19-2020, 03:10 AM   #9
Lawrie
Senior Member
 
Lawrie's Avatar
 
Join Date: May 2010
Location: Qld, Australia
Posts: 3,788
Default Re: 1936 pickup changing motor to a mercury motor

The smoothest engine we have used in the 33 was the stock 33 babbit engine ,would pull 75 mph up a hill .
Lawrie
Lawrie is offline   Reply With Quote
Old 01-19-2020, 12:19 PM   #10
rotorwrench
Senior Member
 
rotorwrench's Avatar
 
Join Date: Jun 2010
Location: San Antonio, Texas
Posts: 12,989
Default Re: 1936 pickup changing motor to a mercury motor

Quote:
Originally Posted by Brian View Post
The late to early motor adapters would have to be used to fit the engine mounts


Actually...no adapters required, just run the truck pumps. This pertains to 8BA series

8RT pumps won't work as well in tight confines so I recommended 37 to 48 pumps with single belt to give more frontal room and fit the old style generator fan better. This is when you need the adapters from Drake.
https://www.bobdrake.com/FordItem.as...5-f427c44eff61

Other things will work too but this is the easiest for bolt on parts. Removing the front pulley from a 42 through 48 crank pulley would be the only mod that would require machining. The crank snout can also be shortened to fit the early short snout pulley too. The 8RT pulley is pretty big.

Last edited by rotorwrench; 01-19-2020 at 07:00 PM.
rotorwrench is offline   Reply With Quote
Old 01-19-2020, 01:20 PM   #11
Brian
Senior Member
 
Brian's Avatar
 
Join Date: May 2010
Location: Masterton, New Zealand
Posts: 3,167
Default Re: 1936 pickup changing motor to a mercury motor

Rotor, with respect, those adapters are for fitting later engine into 33-34 chassis. From 35 onward, the width of the mounts is the same throughout.
__________________
Unfortunately, two half wits don't make a whole wit!
Brian is offline   Reply With Quote
Old 01-19-2020, 02:40 PM   #12
V8COOPMAN
Senior Member
 
V8COOPMAN's Avatar
 
Join Date: May 2010
Location: East Shore of LAKE HOUSTON
Posts: 8,547
Default Re: 1936 pickup changing motor to a mercury motor

Plus, fan clearance is not as critical on the pick-up as it is on the car. The radiator on the truck does not lean to the rear as much as a car does. DD
__________________
Click Links Below

'35-'36 W/8BA & MECHANICAL FAN


T5 W/TORQUE TUBE
V8COOPMAN is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Sponsored Links (Register now to hide all advertisements)


All times are GMT -5. The time now is 03:43 PM.