beheaded cutlass

March 26th, 2009, 09:52 PM

Gents, within the scope of my knowledge of Olds design, I know big block heads can be bolted on small block motors. I've got a strong '72 350 but I wanted to pour some tabasco sauce in the tank if you will. My thoughts were to remove the old heads and stick on a set from a 455; preferably from a '70 W-30. Now I know I may be reaching far on this one, but any thoughts? Even aftermarket with specs comparable to the legendary Cobra Jet motor: 2.200-inch intake and 1.760-inch exhaust would be nice.

64Rocket · March 27th, 2009, 12:30 AM

You would lose compression for the cumbustion chamber on the big block heads are 80 to 84 CC's. small block heads are 60 to 64 CC's. The ports in the big block head will cause problems with the intake. The size valves you are talking about will never happen in an Olds head, there is not enough spacing between valves to go that big. You can put 2.00" / 1.62 valves in the small block heads.

Gene

J-(Chicago) · March 27th, 2009, 12:46 AM

Why stop at just heads?
Get a whole big block!

citcapp · March 27th, 2009, 08:14 AM

X2 on the big block a 70-71 big block will really wake up your Olds

2blu442 · March 27th, 2009, 08:58 AM

And changing from a small block to a big block is pretty straightforward. There are threads talking about the few tweaks you need to be aware of, try a search on the topic. John

March 27th, 2009, 11:05 AM

Thanks for the Intel. Bigger block would be optimum, but I was thinking, seeing she still appears to have a whole lot of life in her (And I got her all fancied up), that I would use a set of Edelbrock heads with 2.072'' intake valves and 1.680'' exhaust valves. The only stipulation is I would have to change the intake of course (3711).

64Rocket · March 27th, 2009, 10:30 PM

If you use the E-brocks, you will need a set of roller rockers and harden push rods. Also there is a problem with the mechanical fuel pump and clearing the head. I have heard that you have to clearence the head. But if you go to far, you will hit water. Plus you wil have to mill the heads to get the combustion chamber CC's down to a usable number.
Anything is possible, it has been done, you can make it work. Go for it.

Gene

March 27th, 2009, 10:47 PM

Gene, hey bro, you seem to be the coach on this one, what would you do then, because Edelbrock makes it seem so simple?

March 27th, 2009, 10:50 PM

How do I go about putting those valves in my heads (2.00" / 1.62 valves in the small block heads)
(ignorance on certain topics is a curse of mine

March 26th, 2009, 09:52 PM	#1 (permalink)
christine fury Guest Posts: n/a	beheaded cutlass Gents, within the scope of my knowledge of Olds design, I know big block heads can be bolted on small block motors. I've got a strong '72 350 but I wanted to pour some tabasco sauce in the tank if you will. My thoughts were to remove the old heads and stick on a set from a 455; preferably from a '70 W-30. Now I know I may be reaching far on this one, but any thoughts? Even aftermarket with specs comparable to the legendary Cobra Jet motor: 2.200-inch intake and 1.760-inch exhaust would be nice. Last edited by christine fury; March 26th, 2009 at 09:52 PM.. Reason: correction

March 27th, 2009, 12:30 AM	#2 (permalink)
64Rocket Registered User Join Date: Sep 2006 Location: Union City Calif.94587 Posts: 301	You would lose compression for the cumbustion chamber on the big block heads are 80 to 84 CC's. small block heads are 60 to 64 CC's. The ports in the big block head will cause problems with the intake. The size valves you are talking about will never happen in an Olds head, there is not enough spacing between valves to go that big. You can put 2.00" / 1.62 valves in the small block heads. Gene __________________

March 27th, 2009, 12:46 AM	#3 (permalink)
J-(Chicago) Seasoned beater pilot. Join Date: Jan 2007 Location: Chicago Posts: 2,697	Why stop at just heads? Get a whole big block! __________________ I'd rather have a numbers matching poker hand.

March 27th, 2009, 08:14 AM	#4 (permalink)
citcapp Super Moderator Join Date: Nov 2007 Location: Bothell, WA Posts: 3,455	X2 on the big block a 70-71 big block will really wake up your Olds __________________ Pat 1957 Super 88 with a 455 1948 2dr series 76 with a 455

March 27th, 2009, 08:58 AM	#5 (permalink)
2blu442 Moderator Join Date: Sep 2006 Location: Medford, Oregon Posts: 2,261	And changing from a small block to a big block is pretty straightforward. There are threads talking about the few tweaks you need to be aware of, try a search on the topic. John __________________ 1964 Cutlass Factory 4spd 1965 442 4spd 1967 442 Auto 1967 Cutlass Convertible 1967 Cutlass four door daily driver 1968 442 Auto 1969 442 W30 Auto 1970 442 4spd 1971 Cutlass Flat Top Wagon 1973 Che*vy 3/4 Ton 454/TH400 Tow Vehicle Only the tow vehicle is finished!

March 27th, 2009, 11:05 AM	#6 (permalink)
christine fury Guest Posts: n/a	Thanks for the Intel. Bigger block would be optimum, but I was thinking, seeing she still appears to have a whole lot of life in her (And I got her all fancied up), that I would use a set of Edelbrock heads with 2.072'' intake valves and 1.680'' exhaust valves. The only stipulation is I would have to change the intake of course (3711). Last edited by christine fury; March 27th, 2009 at 11:08 AM..

March 27th, 2009, 10:30 PM	#7 (permalink)
64Rocket Registered User Join Date: Sep 2006 Location: Union City Calif.94587 Posts: 301	If you use the E-brocks, you will need a set of roller rockers and harden push rods. Also there is a problem with the mechanical fuel pump and clearing the head. I have heard that you have to clearence the head. But if you go to far, you will hit water. Plus you wil have to mill the heads to get the combustion chamber CC's down to a usable number. Anything is possible, it has been done, you can make it work. Go for it. Gene __________________

March 27th, 2009, 10:47 PM	#8 (permalink)
christine fury Guest Posts: n/a	Gene, hey bro, you seem to be the coach on this one, what would you do then, because Edelbrock makes it seem so simple?

March 27th, 2009, 10:50 PM	#9 (permalink)
christine fury Guest Posts: n/a	How do I go about putting those valves in my heads (2.00" / 1.62 valves in the small block heads) (ignorance on certain topics is a curse of mine

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