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Discussion Starter #1
Hello
I'm going to build a GTO 67 engine from the start it's a YS 400 I've got 670 heads I'd thought a stoker set 462 cui but what camshaft and lifters should I choose I've just headed the original rock star 4 barrel carburetor and intake
Best Regards
Thomas
 

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Hello
I'm going to build a GTO 67 engine from the start it's a YS 400 I've got 670 heads I'd thought a stoker set 462 cui but what camshaft and lifters should I choose I've just headed the original rock star 4 barrel carburetor and intake
Best Regards
Thomas

In the upper right of this page you will find a red SEARCH button. If you type "camshaft" in the box and click on the SEARCH button it will pull up a lot of info. You can read through the many threads already covering camshaft selection and engine builds to get an idea of cam choices. :thumbsup:
 

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Opinions differ, especially on cams. So, these are my own personal opinions. I have no quarrel with those who have different opinions.

(1) Compression: Some say that the 670 heads tend to increase the chances of detonation. So, when you order your stroker assembly, it might be a good idea to order pistons that will reduce the CR down to no more than 9:1.

(2) Cam: The smallest cam I'd even consider is the Summit 2801. It will have a dead smooth idle, plenty of vacuum, and lots of low rpm torque. But, the power will begin to fall off at somewhere around 5000 rpm or less. If you never plan to pull past 5000 rpm, then the 2801 might be OK for you. But, most Pontiac guys consider the 2801 too small for a 455+ Pontiac engine. A similar, but low lift version of this cam is the Pontiac 068 cam, which was used in the 455HO engines.

The Summit 2802 is considered, by many, a decent 455+ cam. It is probably the cheapest decent 455+ cam available. It'll still have a decent idle & vac, and will make good power to 5000 rpm.

https://www.summitracing.com/parts/sum-2802?seid=srese1&cm_mmc=pla-google-_-shopping-_-srese1-_-summit-racing&gclid=CjwKCAjw64bPBRApEiwAJhG-fu4aLOTHyW3m1kumqoBBX8-RzGGxietZQw_KF_FlLQq1jbmLPSeP7RoCJdgQAvD_BwE

Just above the 2802 is the Crane 283951.

https://www.summitracing.com/parts/crn-283951?seid=srese1&cm_mmc=pla-google-_-shopping-_-srese1-_-crane-cams&gclid=Cj0KCQjwhrzLBRC3ARIsAPmhsnU0u54qydmvH3kgPclzar4EixRF9nyONKDNg0eySh9VIuf6FmIYCaIaAusEEALw_wcB

Just above that is the Crower 60243.

https://www.summitracing.com/parts/cro-60243?seid=srese1&cm_mmc=pla-google-_-shopping-_-srese1-_-crower&gclid=Cj0KCQiAkZHTBRCBARIsAMbXLhFSuQd1tuCHOjyZ3A1eD7Zabfw4BdQpgMfUo3GOBgyg1WO3k0_RNlgaAjsAEALw_wcB

Next up might be something like the Howard's 410051-14.

https://www.summitracing.com/parts/hrs-410051-14/overview/make/pontiac

Then, the 041 clone, such as the Melling SPC-8, Comp Cams 51-116-3, & Crower 60919, is still considered a good 455+ street cam. I prefer one of these, used with Rhoads lifters. With the Rhoads lifters, this cam has a decent idle, vac, low end torque, and will pull past 5000 rpm easily.

https://www.summitracing.com/parts/cca-51-116-3?seid=srese1&cm_mmc=pla-google-_-shopping-_-srese1-_-comp-cams&gclid=Cj0KCQiAkZHTBRCBARIsAMbXLhF5Bp_9sTsiJxY9M_x8ikv43IYtKPQeOM68uID57dbW40jSc65CjEsaAkSpEALw_wcB

https://www.summitracing.com/parts/rhl-9518l/overview/

Some, including at least one well known Pontiac engine builder, like the Lunati Voodoo cams. So, a 268 Voodoo might be a good street cam.

http://www.lunatipower.com/Product.aspx?id=1776&gid=287

There are obviously bigger cams, and roller cams, available for Pontiac engines. But, if you'll be operating below 5000 rpm, MOST of the time, why buy a cam that will make more power above 5000 rpm, but have a rougher idle, less vac, and less low rpm torque ? In other words, it's better to buy a cam that matches the rpm range you'll be operating in, most of the time. IMO
 

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Discussion Starter #4
Hey guys
thank you
I think I'm trying to find some original setup
but which pistons and cam / lifters
should I use
I would like a little more hp
I have been rebuilt with head 670
has the original input and 4 bbl
Block 67 YS code 400cui
 
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