351 to 302 length rods in a 351 - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars
LinkBack Thread Tools Display Modes
post #1 of 3 (permalink) Old 08-31-05, 05:50 AM Thread Starter
Registered User
Join Date: May 2005
Location: Oberon
Posts: 12
351 to 302 length rods in a 351

Has anyone had any experience with testing the two different rod lengths and the effect it has on breathing and what if any camshaft changes did you make to optimise the setup for maximum power, going from a 351 to a 302 length rod.It is to be used for circuit racing, with a rev limit of 7000RPM.I am looking for around 650HP@ 65000RPM
Engine specs.
comp 11.2:1
Heads 4v
Extractors Pacemaker 17/8" 4 into one
Manifold Funnelweb 4V
Rods 302c
Carb. 825 D.P.

phildownunder is offline  
Sponsored Links
post #2 of 3 (permalink) Old 09-01-05, 02:54 AM
Registered User
gus351's Avatar
Join Date: Aug 2005
Posts: 92
Re: 351 to 302 length rods in a 351

hi phildownunder,
in the combo you suggest a 302 rod would be out of its league of power handling, but the rod length is a good choice.

For a circuit car, or any other car being held at sustained high revs, longer rods can be an advantage.

They give a better rod stroke ratio, which in effect givees greater dwell at top dead centre, hence more torque and smoother high rpm.
The other advantage is of geometry. Because the rod is longer the angle to the bore is reduced at 90 degrees before and 90 degrees after top and bottom dead centres. (and everywhere in between)

The net effect of all of the above is that the pistons exerts less lateral force on the cylinder wall and reduced risk of punching holes in blocks.

The longest rod combo is around 6.250" with a custom piston, and would be advisable to resize the crank down to 2.10 inches and use chevy big end bearings. This also reduces speed across the bearing face and big end failure risk.

Hope this helps
gus351 is offline  
post #3 of 3 (permalink) Old 09-04-05, 06:08 AM
Registered User
Join Date: Jun 2003
Location: Townsville
Age: 44
Posts: 1,212
Re: 351 to 302 length rods in a 351

I have a new set of ACL pistons and moly rings to suit 302C rod in a 351C block but they suggest only 10.5:1 comp ratio so prob not what u want.

clevo400 is offline  
Sponsored Links

  Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars > The Garage - Tech Forums > Engine Specific Tech > Cleveland Tech

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode

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
Trackbacks are On
Pingbacks are On
Refbacks are On

For the best viewing experience please update your browser to Google Chrome