Cam in a 350 2bbl? - Pontiac GTO Forum
User Tag List

 
LinkBack Thread Tools Display Modes
post #1 of 6 (permalink) Old 02-24-2012, 08:28 AM Thread Starter
 
Icefan71's Avatar
 
Join Date: Apr 2011
Location: Winfield, PA
Posts: 240
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Cam in a 350 2bbl?

Just a thought. Would it benefit me to put a Summit 2800 cam in my 72 350 2bbl? I have a gasket kit and a new harmonic balancer going in it. Just wondering if while its apart a cam upgrade would give it a little more power. This is the stock original motor with 7H1 heads that I want to clean up and run in my 72 Lemans. I'm happy with it the way it is. Like I said, its just a thought. I found tons of stuff about a 4bbl swap and a cam change, but nothing about a cam in a 2bbl motor. The Summit cam specs - 204/214 @ .050, .420/.442 lift, 112 lsa. I got these numbers from a stock replacement cam - .198/.208, .269/.272, 111 lsa.

Last edited by Icefan71; 02-24-2012 at 08:46 AM.
Icefan71 is offline  
Sponsored Links
Advertisement
 
post #2 of 6 (permalink) Old 02-24-2012, 10:08 AM
Super Moderator
 
BearGFR's Avatar
 
Join Date: Aug 2008
Location: Springtown, TX
Posts: 5,731
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 122 Post(s)
Garage
That sounds like a good mild/moderate cam. You're not going to see a huge difference, and too it's going to be somewhat limited by the 2-bbl and (I assume) factory exhaust. Keep in mind that smaller displacement engines are more sensitive to cam changes --- meaning a cam that has a dead smooth idle in a 455 might have a bad case of "rumpity rump" in a 350. It'd be good for you to do some research on the topic of cams, torque, horsepower, rpm, and how all those topics are inter-related just so you don't get any unpleasant surprises. (Here's a hint: Horsepower is calculated from torque and rpm. What going to a "bigger" cam actually does is move the torque peak higher in the rpm range, it doesn't make more peak torque, it just changes where the peak is. Since horsepower is calculated from torque and rpm, that's how you get the horsepower "increase" -- from the rpm change. There's a price -- moving the torque curve "higherr" in the rpm band means that a low rpm, the motor's actually making LESS torque than it was before and if you go too crazy you wind up with something that's really ugly and unpleasant to drive under "normal" conditions.)

Bear

BearGFR
Springtown, TEXAS
BearGFR is offline  
post #3 of 6 (permalink) Old 02-24-2012, 10:39 AM Thread Starter
 
Icefan71's Avatar
 
Join Date: Apr 2011
Location: Winfield, PA
Posts: 240
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I'm trying to wrestle a 67 400 4bbl away from its owner that I plan on rebuilding. With that in mind I have a Summit 2.5 inch exhaust system and Pypes 2.5 inch downpipes for the car. I didn't plan on spending too much money on the 350. I just want to change out the dried up gaskets and repaint it so I can run it temporarily. Swapping to a 4bbl wasn't in my plans, but I guess its possible.
Icefan71 is offline  
 
post #4 of 6 (permalink) Old 02-24-2012, 10:45 AM
Super Moderator
 
BearGFR's Avatar
 
Join Date: Aug 2008
Location: Springtown, TX
Posts: 5,731
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 122 Post(s)
Garage
Well. ok then.... of course it's your money, but if you're planning on swapping in a 400 later anyway, then why waste any of it on cam, lifters, pushrods, and rockers for a 350? (All those components need to be replaced together when you do a flat tappet cam change). Ifn' it wuz me, I'd save the bucks for putting into beefing up the 400. Your call though...

Bear

BearGFR
Springtown, TEXAS
BearGFR is offline  
post #5 of 6 (permalink) Old 02-24-2012, 01:45 PM Thread Starter
 
Icefan71's Avatar
 
Join Date: Apr 2011
Location: Winfield, PA
Posts: 240
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by BearGFR View Post
Well. ok then.... of course it's your money, but if you're planning on swapping in a 400 later anyway, then why waste any of it on cam, lifters, pushrods, and rockers for a 350? (All those components need to be replaced together when you do a flat tappet cam change). Ifn' it wuz me, I'd save the bucks for putting into beefing up the 400. Your call though...

Bear
That reminds me of my wife when she says she needs a new pair of shoes, lol. Well it was just a thought. Now if I could just get that guy to give up his 400 already.
Icefan71 is offline  
post #6 of 6 (permalink) Old 02-24-2012, 03:11 PM
 
Instg8ter's Avatar
 
Join Date: Sep 2010
Location: Near Detroit
Posts: 3,930
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 23 Post(s)
Start with a 700 CFM Quadrajet 4 barrel and the RA exhaust with the 2.5" pipes and see how she likes it, may pep it up enough for now and all that is money well spent towards the 400 swap as they will all interchangeable.

Instg8ter is offline  
Sponsored Links
Advertisement
 
Reply

  Pontiac GTO Forum > The 1964-1974 Pontiac Tempest, Lemans & GTO > 1964-1974 Tempest, LeMans & GTO Engine Tuning and High Performance

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Pontiac GTO Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in











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



Similar Threads
Thread Thread Starter Forum Replies Last Post
68 2bbl 400 68goatragtop 1964-1974 Tempest, Lemans & GTO General Discussion 11 04-26-2011 09:45 PM
1972 400 2bbl to 4bbl Conversion jpdog357 1964-1974 Tempest, Lemans & GTO General Discussion 13 10-31-2009 03:00 PM
67 gto 2bbl carb choke problem bnichols04 1964-1974 Tempest, LeMans & GTO Technical and Electrical Wiring 5 10-08-2007 10:04 AM
67 lemans 2bbl electirc choke? bnichols04 1964-1974 Tempest, LeMans & GTO Technical and Electrical Wiring 7 09-06-2007 09:03 PM
Advice - How to wake up my '72 400 2bbl jpdog357 1964-1974 Tempest, LeMans & GTO Technical and Electrical Wiring 5 03-30-2007 08:01 AM

Posting Rules  
You may post new threads
You may 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