Well If I dont damage my passenger side head trying to remove the last bolt I may concider using them (peanut port). Is there a large power and performance loss if I use them, I mentioned before id like about 500HP out of this 454 when im done, daily driver... I found these on ebay, there oval port, new valve job, alot nicer than mine!

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=7937537515&rd=1&sspagename=STRK%3AMEBI%3AIT

Phil

check out these closed chamber large ovals. they are rebuilt, the guy wants $450 on a buy it now and lives in sacremento.

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&category=33617&item=7938324469&rd=1&ssPageName=WDVW

Brandon,
How funny, I just saw those and was going to post it. Im confused though, mortec.com says his heads are peanut port, but oval? These might be the same heads as mine.

Those are not peanut port. they are the large ovals. (the heads referenced by ratonastick.)

Peanuts didn't show up until mid 70's or so (I think I have that time pretty close) and they were never closed chamber, just open. Matter of fact, I've never seen an original set of peanuts with factory orange paint on them.

those are different chambers which one do you need?... mike

Originally posted by 69ralleygreen:
those are different chambers which one do you need?... mike hes rebuilding the engine, he can select what ever piston he wants to work with the heads he decides on using.

one of the things that is nice about a closed chamber head is that they require less dome on the piston to achieve the same compression as an open chamber head. which is beneficial because of the fact the pistons are lighter.

Phil

keep in mind, flat top pistons will work with either open or closed chamber heads. but domed pistons designed for a open chamber head will not work with a closed chamber head. BUT a closed chamber piston will work with a open chamber head.

hopefully that makes sense.

I couldnt tell right off if they were from his pictures. But Mortec.com says there peanut ports? Peanut port are perfectly round or oval shaped? I need to post a picture of mine, it says there peanuts and the ports are round. Im not sure what I need... just something reliable and power worthy.

Maybe a silly question but whats the difference between an open and closed chamber head?

Ok, there are 2 sets in Sacramento I thought you saw these:

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=7938319316&rd=1&sspagename=STRK%3AMEWA%3AIT

Pistons for an open chamber head are usually more expensive than pistons for a closed chamber head. In my experience anyway...

Lance

Phil

open and closed chambers refer to the combustion chamber. closed chamber heads have a smaller chamber and open heads have larger chambers.

to see the difference between a peanut, large oval and rectangle ports heads check the pics posted in this thread.

http://www.chevelles.com/forum/ultimatebb.php/topic/4/21262.html#000000


the "390" closed chamber heads i linked to earlier are large oval passenger car heads. chevrolet never put any peanut port heads on any passenger car engine, only trucks. look over at mortec again and look for the 390 head.

the "360" heads you listed are peanut port heads. i did see them and noticed they were being sold by the same guy in sacramento, but didnt refer to them because they were peanuts.

This should be Jakeshoe's BB head link that show's pic's of the differences between them. But I'm too stupid ta get it ta work????

pdq67

BB Head picture link from Team Chevelle http://www.chevelles.com/cgi-bin/forum/ultimatebb.cgi?ubb=get_topic&f=4&t=021259#000005

Cool post, very useful! So when it comes time to put on my intake, probably an airgap edelbrock, do those ports have to match the heads?

If I use the peanut port heads can I change the pistons I use to compensate for them, well basically can 500 HP be made on them? I figure the cost of getting a valve job on them and cleaning them up, maybe a light resurface I could just buy some like this one guy has.... Peanuts,... hmm smile.gif

If I remember correctly the air gap, doesnt it only come in Rectangle port? Which is larger than a peanut port isnt it? Seems like it would hold back alot of flow... I never really thought about this stuff before.

the Air Gap intake comes in large oval port as well

Phil

here is Chris aka mr 4 speed's combo. the car has run a best of 12.99 with 2.56 gears in a full weight 70 chevelle!!! he drives the car to the track which i believe he said was over 100 miles one way!! hes using closed chamber large ovals with stock valves on a 454.

if there is a combo out there that will fit your needs its his.

originally posted by mr 4 speed
my combo is:
.030 454
.100 domed Speed Pro hypertectic pistons (about 10.5 to 1 compression with .008 piston/deck clearance and 101 cc chamber heads)
stock rods w/ARP rod bolts
stock steel crank (cast is fine)
stock replacement oil pan (Milodon)
#215 closed chamber heads
stock,unported with stock 2.06/1.72 valves
stock rockers
Ultradyne flat tappet hydraulic 280/288 advertised
223/231 @ .050 .525/.550 112 LSA
Performer RPM
750 vacuum secondary Holley 3310
Accel blueprint HEI
1 3/4" primary tube headers
2.5" exhaust w/mandrel bent tails
Just a stock 454 built to 1970 LS5 specs with a cam,intake,and headers.
It's reliable combo as well.
I now have 3.31 gears.
It averaged 13.30-13.40's w/2.56's with a best of 12.99 in mineshaft air and perfect starting line condtions
I'm expecting 12.90's or better consistently once its dialed in with the new gears.
Trans is a stock TH400/2400 B&M Holeshot convertor

Personally.....I wouldn't even consider using the peanut port heads. My engine builder calls them "Whistlers". The ports are so small the air whistles through them.
Take your time, shop around and find the open chamber large ovals. Find some that aren't cracked, but need rebuilding and have them done. This way you aren't buying someone elses machine work....that you really don't know anything about. Unless of course you buy them from one of the members here.
In fact, square port heads work just fine on a street engine too. Despite what others say, the two heads are about a toss up performance wise. 2 of my buddie had LS6 engines in their 70 Chevelles and I had a tweaked LS5. We all ran within a tenth of each other at the drags. 12.0's by the way.
Have fun!
Ron