'69 Cutlass S
#1
'69 Cutlass S
Recently acquired a 1969 Cutlass S. Vehicle runs well. Has the original 350 motor but I see where someone put 5A heads on it. Research tells me that these are from an eighties 307.
My question is how much power loss is there with these heads compared to the original #5's ? The car has about 90 K miles on it so I plan to eventually pull the motor for a rebuild & replace heads with the #5 heads.
Just curious to know what people think of this application.
Thanks !
My question is how much power loss is there with these heads compared to the original #5's ? The car has about 90 K miles on it so I plan to eventually pull the motor for a rebuild & replace heads with the #5 heads.
Just curious to know what people think of this application.
Thanks !
#2
Recently acquired a 1969 Cutlass S. Vehicle runs well. Has the original 350 motor but I see where someone put 5A heads on it. Research tells me that these are from an eighties 307.
My question is how much power loss is there with these heads compared to the original #5's ? The car has about 90 K miles on it so I plan to eventually pull the motor for a rebuild & replace heads with the #5 heads.
Just curious to know what people think of this application.
Thanks !
My question is how much power loss is there with these heads compared to the original #5's ? The car has about 90 K miles on it so I plan to eventually pull the motor for a rebuild & replace heads with the #5 heads.
Just curious to know what people think of this application.
Thanks !
#4
Just an Olds Guy
Join Date: Jul 2008
Location: Edmonton, AB. And "I am Can 'eh' jun - eh"
Posts: 24,525
#5
Just an Olds Guy
Join Date: Jul 2008
Location: Edmonton, AB. And "I am Can 'eh' jun - eh"
Posts: 24,525
#6
Allen, will check my casting numbers. Thanks. So what you are saying is that these "5A" stamped heads could be the original heads that came with this 350 motor (68-76).
If so, would they be the same as the #5 heads in respect to CR, size of valves, & flow ?
I know that a 5A head was made for 1980"s Olds 307's also but what I am hearing from forum members is that head would not fit on the (68-76) 350 motor. Is that correct ?
Thanks !
If so, would they be the same as the #5 heads in respect to CR, size of valves, & flow ?
I know that a 5A head was made for 1980"s Olds 307's also but what I am hearing from forum members is that head would not fit on the (68-76) 350 motor. Is that correct ?
Thanks !
#8
Just an Olds Guy
Join Date: Jul 2008
Location: Edmonton, AB. And "I am Can 'eh' jun - eh"
Posts: 24,525
Allen, will check my casting numbers. Thanks. So what you are saying is that these "5A" stamped heads could be the original heads that came with this 350 motor (68-76).
If so, would they be the same as the #5 heads in respect to CR, size of valves, & flow ?
I know that a 5A head was made for 1980"s Olds 307's also but what I am hearing from forum members is that head would not fit on the (68-76) 350 motor. Is that correct ?
Thanks !
If so, would they be the same as the #5 heads in respect to CR, size of valves, & flow ?
I know that a 5A head was made for 1980"s Olds 307's also but what I am hearing from forum members is that head would not fit on the (68-76) 350 motor. Is that correct ?
Thanks !
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#9
Just an Olds Guy
Join Date: Jul 2008
Location: Edmonton, AB. And "I am Can 'eh' jun - eh"
Posts: 24,525
Do you know where to look for your head casting (6 digit) number?
#11
Allan, I have had two 72 Cutlasses with 350's. My point I was making is the heads are 7a (note lower case a) and not 7A (note upper case A). In post #4 you were saying 72 was 7A (upper case).
#12
First, the block number doesn't "suggest" that it's a 350, it PROVES that it's a 350. Unfortunately, that is irrelevant. What is the HEAD casting number, above the center two exhaust ports. That's what matters.
#13
Just an Olds Guy
Join Date: Jul 2008
Location: Edmonton, AB. And "I am Can 'eh' jun - eh"
Posts: 24,525
#14
OK. Checked under several layers of grime & found the heads to be stamped: 397 742A
Nice to know they are at least period correct. I am planning to have this engine/heads rebuilt in the near future.
Thanks to all who responded.
Nice to know they are at least period correct. I am planning to have this engine/heads rebuilt in the near future.
Thanks to all who responded.
#15
Sorry I meant to put 7A heads were 1972, not 71. I would like a set of those 5A 350 heads to hide a bigger motor on a 83/84 Hurst/Olds or a 85 442.
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