Thread Tools Display Modes
Prev Previous Post   Next Post Next
  #32  
Old 07-03-2026, 10:00 AM
Bill Hanlon's Avatar
Bill Hanlon Bill Hanlon is offline
Ultimate Warrior
 
Join Date: Feb 2005
Location: Fredericksburg, TX
Posts: 2,645
Default

I am no 4 cylinder Pontiac expert, but I read your post and thought "If he can't find a Trophy 4 cam, why not use a V8 cam?" So then I Googled "can you use a Pontiac V8 camshaft in a Pontiac Tempest 4 cylinder engine?". The answer I got was ....

"Yes, you can use a standard Pontiac V8 camshaft in a 1961–1963 Pontiac Tempest 4-cylinder engine (the 194.5ci "Trophy 4"). Because Pontiac made the 4-cylinder by essentially cutting a 389 cubic-inch V8 in half, the cam dimensions match."

... but that was followed by ...

"However, there is a catch regarding engine rotation.

The 1961–1963 "Trophy 4" (Pushrod Engine)Compatibility: The camshafts for early V8s and the 4-cylinder share the same lobe spacing, base circle, and block-mounted design.

The Catch: Some early 4-cylinder Tempests used a unique "rope drive" flexible driveshaft that connected to a rear-mounted transaxle. These specific engines rotated backwards (counter-clockwise). If your 4-cylinder is a standard, front-mounted engine, a V8 cam will work. If your Tempest has the unique rear-mounted transaxle, a standard V8 cam will run your engine in reverse."

... REALLY? I thought ALL 4 cylinder Tempests used the flex driveshaft. And I've never heard that the half-a-V8 engine turned backwards.

Anyway, if the Trophy 4 does NOT rotate backwards and you can find specs for the cam you are looking for I'd bet that you could find a Pontiac V8 cam with similar specs.

My apologies if the Trophy 4 really does turn backwards.

__________________
My Pontiac is a '57 GMC with its original 347" Pontiac V8 and dual-range Hydra-Matic.
 


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


All times are GMT -4. The time now is 09:18 PM.

 

About Us

The PY Online Forums is the largest online gathering of Pontiac enthusiasts anywhere in the world. Founded in 1991, it was also the first online forum for people to gather and talk about their Pontiacs. Since then, it has become the mecca of Pontiac technical data and knowledge that no other place can surpass.

 




Copyright © 2017