Head selection

Adger Smith · 11-05-2015, 01:54 AM

What head casting number would you select for a 1.94 valve 350 stocker if you had 4 numbers to chose from?
450, 703, 624, 556
PM or e-mail me if you are bashful
adgersperf@aol.com
Thanks,
Adger Smith

Mike Taylor 3601 · 11-05-2015, 10:24 AM

I know this will probably get bashed, but oh well.
I know flow #'s aren't the whole story,but all the small blocks I have checked I can remember off top of my head 450,416(1.84/1.50 or 1.72/1.50)for 305 624,882 350(1.94/1.50) for 350 flow #'s are so close together AT .400'' LIFT AND BELOW that it wouldn't matter which one you used. about 165 cfm @25''@400(.388'' using lift/diameter ratio)is what I see on a SF-600 on those castings.
Mike Taylor 3601

REGGIE WINKLES · 11-05-2015, 11:57 AM

Adger, I would go with the 76 cc- 624 casting all the way. If not mistaken I think the 450 & 556 castings have the 1.72 intake valve. I have seen a lot of the 624 heads used. Don't know anything about the 703 head.

Adger Smith · 11-05-2015, 10:06 PM

There are two versions of the 462624 head that I know of. There was a version from 1971 thru 1977 and another from '78 to '86. I'm assuming the late one is the version that is redesigned to save weight. Is it the earlier one that is more desirable?
There is also a 458624 listed that was in an early and late version, but I've never seen one & it is not on the NHRA list. Must have been in trucks only.
703 head is listed as:
1978-1980 HP 350/220/225/230 1.94 1.50 78cc chamber

Mike Taylor 3601 · 11-06-2015, 10:49 AM

I can't remember any 624's besides the lightweight version,can't remember ever seeing 703,556 heads.
Mike Taylor 3601

Bench Racer · 11-06-2015, 06:07 PM

Adger, my brother David ran a 624 head super stock combination several years ago. I think it was a 1981 Chevy 350/175hp engine with a Q-jet. It was a very stout piece in SS but had some "high dollar" heads on it. Not sure how they would flow in stocker trim. The numbers were 462624.

Chipper Chapman · 11-07-2015, 06:08 PM

624 was the lightweight version of the 882. Very prone to cracks and many cores only had a 1.72 intake.

FED 387 · 11-07-2015, 06:37 PM

Sm valve 624 came on L48--- large valve on L82--- 75 and later heads have an EXTRA exhaust manifold bolt hole ---VERY prone to cracking ---check around coolant holes and between valve seats--FED 387

11-05-2015, 01:54 AM	#1
Adger Smith VIP Member Join Date: Dec 2001 Location: Texarkana Ark/TX Posts: 2,446 Likes: 575 Liked 880 Times in 311 Posts	Head selection What head casting number would you select for a 1.94 valve 350 stocker if you had 4 numbers to chose from? 450, 703, 624, 556 PM or e-mail me if you are bashful adgersperf@aol.com Thanks, Adger Smith __________________ Adger Smith (Former SS)

11-05-2015, 10:24 AM	#2
Mike Taylor 3601 VIP Member Join Date: Oct 2008 Location: Somerset,Ky Posts: 1,371 Likes: 352 Liked 304 Times in 102 Posts	Re: Head selection I know this will probably get bashed, but oh well. I know flow #'s aren't the whole story,but all the small blocks I have checked I can remember off top of my head 450,416(1.84/1.50 or 1.72/1.50)for 305 624,882 350(1.94/1.50) for 350 flow #'s are so close together AT .400'' LIFT AND BELOW that it wouldn't matter which one you used. about 165 cfm @25''@400(.388'' using lift/diameter ratio)is what I see on a SF-600 on those castings. Mike Taylor 3601

11-05-2015, 11:57 AM	#3
REGGIE WINKLES Member Join Date: Jun 2007 Location: St. Augustine, Fla. Posts: 229 Likes: 569 Liked 39 Times in 9 Posts	Re: Head selection Adger, I would go with the 76 cc- 624 casting all the way. If not mistaken I think the 450 & 556 castings have the 1.72 intake valve. I have seen a lot of the 624 heads used. Don't know anything about the 703 head. __________________ Reggie Winkles 2650/Stock

11-05-2015, 10:06 PM	#4
Adger Smith VIP Member Join Date: Dec 2001 Location: Texarkana Ark/TX Posts: 2,446 Likes: 575 Liked 880 Times in 311 Posts	Re: Head selection There are two versions of the 462624 head that I know of. There was a version from 1971 thru 1977 and another from '78 to '86. I'm assuming the late one is the version that is redesigned to save weight. Is it the earlier one that is more desirable? There is also a 458624 listed that was in an early and late version, but I've never seen one & it is not on the NHRA list. Must have been in trucks only. 703 head is listed as: 1978-1980 HP 350/220/225/230 1.94 1.50 78cc chamber __________________ Adger Smith (Former SS) Last edited by Adger Smith; 11-05-2015 at 10:11 PM. Reason: add 703

11-06-2015, 10:49 AM	#5
Mike Taylor 3601 VIP Member Join Date: Oct 2008 Location: Somerset,Ky Posts: 1,371 Likes: 352 Liked 304 Times in 102 Posts	Re: Head selection I can't remember any 624's besides the lightweight version,can't remember ever seeing 703,556 heads. Mike Taylor 3601

11-06-2015, 06:07 PM	#6
Bench Racer Member Join Date: May 2002 Location: Green Creek (Tryon) North Carolina Posts: 331 Likes: 69 Liked 99 Times in 21 Posts	Re: Head selection Adger, my brother David ran a 624 head super stock combination several years ago. I think it was a 1981 Chevy 350/175hp engine with a Q-jet. It was a very stout piece in SS but had some "high dollar" heads on it. Not sure how they would flow in stocker trim. The numbers were 462624.

11-07-2015, 06:08 PM	#7
Chipper Chapman Member Join Date: Jan 2004 Location: Belmont N.S. Canada Posts: 473 Likes: 246 Liked 166 Times in 71 Posts	Re: Head selection 624 was the lightweight version of the 882. Very prone to cracks and many cores only had a 1.72 intake. __________________ Chris Chapman 1969 Chevelle NHRA F-G/SA 1090

11-07-2015, 06:37 PM	#8
FED 387 VIP Member Join Date: Jun 2006 Posts: 3,419 Likes: 528 Liked 332 Times in 180 Posts	Re: Head selection Sm valve 624 came on L48--- large valve on L82--- 75 and later heads have an EXTRA exhaust manifold bolt hole ---VERY prone to cracking ---check around coolant holes and between valve seats--FED 387

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode