Jump to content
Forums Gone... but not forgotten!

Tired of these Ads? Register Today!

Pontiac of the Month

gscherer78ta's 1978 Trans Am

2019 February
of the Month

  • Welcome to Forever Pontiac

    We are a community of Pontiac enthusiasts. The purpose of our community is to keep alive the Pontiac spirit by sharing (or showing off) our cars, discussing Pontiac, helping each other work on our cars and find information, plus attend various meets/shows/etc... To aid discussion, sharing, event planning and selling of parts/cars/anything, we have various parts of the website to aid this from Forums to an online Garage to Classifieds to even a Document Download Repository. You can find links to these in our navigation above based on what each section helps with (discussion, local events, learning, etc...).

    We invite you to contribute, find help or just view some of our member's amazing cars! Don't forget, we also have great contests from time to time (like our Pontiac of the Month and yearly calendar contest) and our Pontiac This OR That, a fun game where you choose the best of two randomly selected Pontiacs from our online garage.

    We look forward to seeing you around!

  • 0
KACEYPERRINE

pontiac heads

Question

i have a base 1973 lemans not sure if engine is 350 or 400 has 2 barrel carb  will 1968 2 barrel heads equal more horsepower mobile dyno at atlanta dragway said 224hp 375tq

Share this post


Link to post
Share on other sites

3 answers to this question

Recommended Posts

  • 0

A 350 block will be stamped 350 or 50 on the block, drivers side above the oil pan. A 400 will be stamped 400 or 00 in the same location.

As for your read question, depends on the head. The most desirable flowing heads have a 2.11" intake and 1.77" exhaust valves. Pontiac made several over the years. However a good machine shop can do wonders with more common 1.96/1.66 heads with a port/polish job to make the head flow. What is the two digit/character designation on your heads? Should be between #1 and 3 cylinders.

  • Thanks 1

Share this post


Link to post
Share on other sites

Tired of these Ads? Register Today!

  • 0

block is a 400 heads are number 4h/4x 7:6:1 compression the heads i want to swap on are are 1968 number 15 heads 10:5:1 compression 

Share this post


Link to post
Share on other sites
  • 0

Actual #15s are from 1970 big cars. Still you definitely get a smaller combustion chamber at 87ccs vs the 98 or 114 ccs of the 1973 motors.

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Answer this question...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


Tired of these Ads? Purchase Enhanced Membership today to remove them!
×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.