Odd heads either side
Thread Starter
Instructor
Joined: Dec 2000
Posts: 108
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From: Derbyshire,England
Odd heads either side
Hi
I have just got the engine out of my car and have started stripping it down and noticed the drivers side head casting number ends 041 whilst the passenger side head casting number ends 186. Is there any significant difference between these heads that will affect how the motor runs? should i junk them ? ( I originally thought that they were both 041's and was going to keep them) and go for some aftermarket heads.
Help
David
I have just got the engine out of my car and have started stripping it down and noticed the drivers side head casting number ends 041 whilst the passenger side head casting number ends 186. Is there any significant difference between these heads that will affect how the motor runs? should i junk them ? ( I originally thought that they were both 041's and was going to keep them) and go for some aftermarket heads.
Help
David
Drifting
Joined: Jul 2001
Posts: 1,418
Likes: 1
Re: Odd heads either side (ukvette72)
Here is a link that might be of some help.Just be carefull not to get as much money tied up in used heads as newer heads cost.
http://home.isoa.net/~mharrisj/sbcheads.html
http://home.isoa.net/~mharrisj/sbcheads.html
Intermediate
Joined: Mar 2002
Posts: 26
Likes: 0
From: Louisville KY
Re: Odd heads either side (ukvette72)
Interesting,
Without knowing the complete casting #'s... I'm looking in my Corvette "black book" here and I see 3927186 is a 1969/70 350 head for a number of HP rating models (300 - 370 HP!). The 3947041 is strictly a 1969 head for the 300 HP 350 motor.
It's interesting because in my "head research" as of late I've learned that while head design is important, it may be the valve train that gives the extra performance (hence the broad power range on the same 3927186 casting above.
I've heard for best balanced performance you should have matching castings. This is probably true even if combustion chamber size is the same and valve sizes! There has got to be an apparent difference in intake runner, exhaust outlets, etc.
If both heads are good, I'd find another 186 and pair it up!
Just an opinion from a Kentucky boy! Yee-haw! Hahaha!
Rod Hisle
Louisville, KY (Home of the Kentucky Derby!)
:flag
Without knowing the complete casting #'s... I'm looking in my Corvette "black book" here and I see 3927186 is a 1969/70 350 head for a number of HP rating models (300 - 370 HP!). The 3947041 is strictly a 1969 head for the 300 HP 350 motor.
It's interesting because in my "head research" as of late I've learned that while head design is important, it may be the valve train that gives the extra performance (hence the broad power range on the same 3927186 casting above.
I've heard for best balanced performance you should have matching castings. This is probably true even if combustion chamber size is the same and valve sizes! There has got to be an apparent difference in intake runner, exhaust outlets, etc.
If both heads are good, I'd find another 186 and pair it up!
Just an opinion from a Kentucky boy! Yee-haw! Hahaha!
Rod Hisle
Louisville, KY (Home of the Kentucky Derby!)
:flag
Le Mans Master
Joined: Aug 2000
Posts: 9,662
Likes: 7
From: Semper ubi, sub ubi
Cruise-In VI Veteran
Cruise-In VII Veteran
Re: Odd heads either side (ukvette72)
According to http://www.mortec.com the 3927186 is ....69-70...302/350......Camel hump,64cc chambers,accessory holes
and the
3947041 is for the, 69-70...302/350......Right angle casting identifier, 64cc chamber, accessory holes, good HP head
Although the castings aren't identical, both the heads are considered the basis for a some pretty good performance heads with some work.
In my uninformed opinion, I'd look for a head that matched either of them and go with it.
and the
3947041 is for the, 69-70...302/350......Right angle casting identifier, 64cc chamber, accessory holes, good HP head
Although the castings aren't identical, both the heads are considered the basis for a some pretty good performance heads with some work.
In my uninformed opinion, I'd look for a head that matched either of them and go with it.
Drifting
Joined: Oct 2001
Posts: 1,699
Likes: 1
From: Westampton NJ
Re: Odd heads either side
186 and 041 are pretty much the same. I'd say buy another 186 and then have the valve seats bored out to 2.02/1.60 and then the appropriate chamber modifications made...
