I.D.ing a big block head...... - The 1947 - Present Chevrolet & GMC Truck Message Board Network

nvrsatisfied · 01-15-2009, 11:45 AM

O.K. first thing first i have did a search and ran across a forum from this site which did give me a little bit more knowledge.....

My question is that my head I.D. #346236 shows different cc ratings on different websites.... so which is it 113cc or 120cc??? Did the "peanut" port exist in a 120cc or only a 113cc???

website-------------rating

MORTEC------------120cc

MINUIT10.net-------113cc

NASTYZ28----------113cc

CHEVYCARCLUBVIC--120cc

67-72CHEVYTRUCKS---- ??????

what i have learned so far is that these heads are the "peanut" port heads, which i understand are good for under roughly 4500rpm at making there power, that is fine with me, since the truck is going to play in the mud.

and as always thanks for any help.

nvrsatisfied · 01-15-2009, 03:20 PM

have i stumped you people?????

or do i not have enough info.....i am still finding websites giving different CC ratings

69sixpackbee · 01-15-2009, 03:33 PM

Split the difference between the two so let's call it 116.5, no?

breeh · 01-15-2009, 04:42 PM

I've had the same frustration with BBC heads and published data. I was told once that there was quiet a bit of variability and the only way to know for sure is to cc them. Drop, drop, drop....

knsmodels · 01-15-2009, 11:24 PM

pics of the comb. chambers would help in identifying.......also are they square ports or ovals on the intake side???

nvrsatisfied · 01-16-2009, 12:00 PM

Quote:

Originally Posted by knsmodels

pics of the comb. chambers would help in identifying.......also are they square ports or ovals on the intake side???

they are oval.....pics of the CC chamber??? how is that going to help...is there a way to look at them and tell, are there #'s or markings i could be looking for?? if you want pics i can get them when i get home....

"clay68c10"- You can do a quickie cc measurement. Get a small piece of plexiglass and a generic syringe from the pharmacy. Put a small hole in the plexiglass, use a little bit of grease to seal it to the combustion chamber and see how many syringes it takes to fill it. It may not be super accurate, but it'll give you a good idea what you've got.

^ good idea i will try this experiment......

Willys47 · 01-16-2009, 12:37 PM

I looked through my books and one has the 346236 cc as 112.0 the vales are 2.06/1.72 the engine is a 454 from 1975-76 truck very small port .This info is from HP books how to rebuild your BB Chevy I found the info in the parts ID section under the cylinder-head casting numbers

knsmodels · 01-16-2009, 09:45 PM

if the heads are off of the vehicle then yes you can tell by looking at the CC what they are......

**clay68c10** · 01-15-2009, 11:53 PM

You can do a quickie cc measurement. Get a small piece of plexiglass and a generic syringe from the pharmacy. Put a small hole in the plexiglass, use a little bit of grease to seal it to the combustion chamber and see how many syringes it takes to fill it. It may not be super accurate, but it'll give you a good idea what you've got.

396C20 · 01-17-2009, 01:09 PM

I just had a set of these rebuilt for my 396 and the combustion chambers are 120cc. Hope this helps.

01-15-2009, 11:45 AM	#1
nvrsatisfied Registered User Join Date: Oct 2007 Location: oklahoma Posts: 457	I.D.ing a big block head...... O.K. first thing first i have did a search and ran across a forum from this site which did give me a little bit more knowledge..... My question is that my head I.D. #346236 shows different cc ratings on different websites.... so which is it 113cc or 120cc??? Did the "peanut" port exist in a 120cc or only a 113cc??? website-------------rating MORTEC------------120cc MINUIT10.net-------113cc NASTYZ28----------113cc CHEVYCARCLUBVIC--120cc 67-72CHEVYTRUCKS---- ?????? what i have learned so far is that these heads are the "peanut" port heads, which i understand are good for under roughly 4500rpm at making there power, that is fine with me, since the truck is going to play in the mud. and as always thanks for any help. __________________ Lug Nuts Classic Rides. (Bodywork, small fab, and Restorations) Perry, Ok. We're just two guys, trying our best. 72 cheyenne super https://67-72chevytrucks.com/vboard/...d.php?t=811512 55 chevy truck http://67-72chevytrucks.com/vboard/s...d.php?t=840174

01-15-2009, 03:20 PM	#2
nvrsatisfied Registered User Join Date: Oct 2007 Location: oklahoma Posts: 457	Re: I.D.ing a big block head...... have i stumped you people????? or do i not have enough info.....i am still finding websites giving different CC ratings __________________ Lug Nuts Classic Rides. (Bodywork, small fab, and Restorations) Perry, Ok. We're just two guys, trying our best. 72 cheyenne super https://67-72chevytrucks.com/vboard/...d.php?t=811512 55 chevy truck http://67-72chevytrucks.com/vboard/s...d.php?t=840174

01-15-2009, 04:42 PM	#4
breeh Recovering 67-72 Addict Join Date: Oct 2000 Location: North Bend, WA Posts: 1,788	Re: I.D.ing a big block head...... I've had the same frustration with BBC heads and published data. I was told once that there was quiet a bit of variability and the only way to know for sure is to cc them. Drop, drop, drop.... __________________ 68 Short Fleet 4x4; 427; BTO Level 3 700R4; NP205; Dana 60 front and rear; 4" lift with 35's; Disc brakes; AGR variable ratio steering; factory bucket seats; factory tach and tilt. "Friends call me cruzer cuz I like fast cars and fast women"

01-15-2009, 11:24 PM	#5
knsmodels I make Models Join Date: May 2005 Location: Bucks, PA Posts: 626	Re: I.D.ing a big block head...... pics of the comb. chambers would help in identifying.......also are they square ports or ovals on the intake side??? __________________ Click to see what I do 1972 LWB K10 350/4 sp 1968 SS Chevelle 396/tremac5spd

01-16-2009, 12:37 PM	#7
Willys47 Registered User Join Date: Dec 2007 Location: Nanaimo B.C. Posts: 604	Re: I.D.ing a big block head...... I looked through my books and one has the 346236 cc as 112.0 the vales are 2.06/1.72 the engine is a 454 from 1975-76 truck very small port .This info is from HP books how to rebuild your BB Chevy I found the info in the parts ID section under the cylinder-head casting numbers __________________ I was hooked on these trucks since 1982 when I drove my budys fathers 1968 Custum GMC 396 automatic dana 60 rear with a power lock diff what a ride more fun then we will we can ever tell!!

01-15-2009, 03:33 PM	#3
69sixpackbee Registered User Join Date: Jan 2001 Location: Sabinal, Texas Posts: 1,706	Re: I.D.ing a big block head...... Split the difference between the two so let's call it 116.5, no?

01-16-2009, 09:45 PM	#8
knsmodels I make Models Join Date: May 2005 Location: Bucks, PA Posts: 626	Re: I.D.ing a big block head...... if the heads are off of the vehicle then yes you can tell by looking at the CC what they are...... __________________ Click to see what I do 1972 LWB K10 350/4 sp 1968 SS Chevelle 396/tremac5spd

01-15-2009, 11:53 PM	#9
clay68c10 Senior Member Join Date: Aug 2004 Location: Centennial, CO Posts: 2,990	Re: I.D.ing a big block head...... You can do a quickie cc measurement. Get a small piece of plexiglass and a generic syringe from the pharmacy. Put a small hole in the plexiglass, use a little bit of grease to seal it to the combustion chamber and see how many syringes it takes to fill it. It may not be super accurate, but it'll give you a good idea what you've got. __________________ ClusterTruck: 68 C10 Bought in 89, wrecked in 03. Slow low $ rebuild started '17. 6.0 & TKO http://67-72chevytrucks.com/vboard/s...d.php?t=788602 93 K1500 Short Step, 350, NV4500, EBL flash ECU. Vortec heads & roller cam someday... 05 Jeep Wrangler Unlimited. 3” lift & 6-speed 02 E320 the insurance total “free car” 13 Tahoe LTZ

01-17-2009, 01:09 PM	#10
396C20 Registered User Join Date: Apr 2006 Location: SoCal Posts: 70	Re: I.D.ing a big block head...... I just had a set of these rebuilt for my 396 and the combustion chambers are 120cc. Hope this helps. __________________ 69 Chev C20 396 T400 Dana 60 3.54 A/C Daily Driver - Stolen 67 Chevy C20 CST



Register or Log In To remove these advertisements.

Register or Log In To remove these advertisements.