My plan all along for the Acadian engine has been a basically stock 327. You guys helped talk me into using the 69 Z28 aluminum intake and a Holley I purchased. I had hoped to build the engine this summer, but summer is running into winter and I hope to do it this wiinter now.
Last week I picked up a set of 20,000km Vortec heads and an aftermarket aluminum intake to run a Holley carb on them. Should I build the 327 with the Vortecs and that now? About 40 more horsepower from them over the stock 327 heads I hear.
Anyone running this setup on a 327, or even a 350?
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1966 Strato Chief 2 door, 427 4 speed, 45,000 original miles
1966 Grande Parisienne, 396 1 of 23 factory air cars
Carl, I have a Vortec 350 in my GMC and I can not say enough good things about this motor, granted it is fuel injected and you will run a carb. This thing has so much torque, the charts say 365 lb. ft. I have often joked that I should swap that motor into the LeMans. It is a strong mill.
Oh, I am familiar with the stock Vortec. We've had a Vortec half ton since 98. Great engines, decent on fuel and nice power.
I guess my question should have been made clearer. It should read something like "Will I gain enough power doing the swap to Vortec heads to make it worthwhile?"
I am pretty bent on keeping the 327 looking close to stock other than the intake maybe. The Vortec head castings don't have the old style look with the bolt holes in the ends, and the newer style valve covers.
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1966 Strato Chief 2 door, 427 4 speed, 45,000 original miles
1966 Grande Parisienne, 396 1 of 23 factory air cars
Carl, I have a Vortec 350 in my GMC and I can not say enough good things about this motor, granted it is fuel injected and you will run a carb. This thing has so much torque, the charts say 365 lb. ft. I have often joked that I should swap that motor into the LeMans. It is a strong mill.
-- Edited by 73SC at 00:09, 2008-10-20
Should convert this GM torque and reliablity storey over to the NA bashing quality storey on the thread truth about automobiles !
Granted we may have had our weaknesses in some areas of the North American vehicles, but as far as I'm concerned, we (GM) have some excellent engines, the Vortec being one. Great power, far superior fuel economy for the power compared to some of the imports.
And who can argue with the LT1's of the 90's, LS1 F bodies, or the 3800 with or without supercharger?
Anyway, still hoping to find someone with real world experience with Vortec heads on a 327!
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1966 Strato Chief 2 door, 427 4 speed, 45,000 original miles
1966 Grande Parisienne, 396 1 of 23 factory air cars
If you want to make more power... use the vortec heads. If you want it to look stock use the 327 heads....
There are fewer "numbers" guys out there every day.
MORE POWER !!!
If you go by the charts GM publishes, in truck applications the Vortec is the same engine as the TBI with the addition of Vortec heads and intake. Makes anywhere from 55 to 75 HP more. Incidently the 5.7 Vortec is the last use of the Chevrolet Small block first introduced in 1955. Here's one complete for $350!
Use the Vortec's, there a far better head for the application. It has better combustion chamber design, short turn radius, amd atomization then the "old" style heads there are out there. Plus, it has harden seats for unleaded fuel. Since you have an intake to go with them, it's a very good way to go. You'll most likely pick up 50Hp over the "old" design stuff. BUT will have to change springs if your going over .480 lift. They do offer kits to use the "old" style valvecovers on the newer center-bold heads, but I've never seen/used them.
Granted we may have had our weaknesses in some areas of the North American vehicles, but as far as I'm concerned, we (GM) have some excellent engines, the Vortec being one. Great power, far superior fuel economy for the power compared to some of the imports.
And who can argue with the LT1's of the 90's, LS1 F bodies, or the 3800 with or without supercharger?
Anyway, still hoping to find someone with real world experience with Vortec heads on a 327!
Carl I have a fresh 327, with original 300 HP heads, and 350 HP cam It is a rocket! but no faster, that a 330HP crate motor, I had with VORTEC heads, in a 72 Chevelle The 72 Chevelle was faster than my buddies, 72 Chevelle with 454 crate motor Sooo use the Vortec heads!! at least 60 HP.. I love the 327, but with the camel hump heads, my alternator is mounted real low..
If you want pure brute horsepower use the vortec heads. You can pick up an additional 40 hp over the stock vortec head with some exhaust port porting. You do not have to touch the intake side. I have an article with dyno test results that compare before and after.
Personally for your car I would use the castings you have and use the vortec heads for somthing else. What casting number heads do you have? 461, 462, 461X or 041 ? Al
carl, i've built a '75 400 (ya, CHEVY) with '97 305 vortec heads for this '69 impala. other than the aforementioned appearance issue, they're the best way to go. the 305 heads have a 58cc chamber, compared to the 350s 64cc chamber. as john said earlier, you're limited to about .480 valve lift before you have to machine the v/guide for clearance. the only problem is the temp sender hole is smaller than the '69 sender...
If you want pure brute horsepower use the vortec heads. You can pick up an additional 40 hp over the stock vortec head with some exhaust port porting. You do not have to touch the intake side. I have an article with dyno test results that compare before and after.
Personally for your car I would use the castings you have and use the vortec heads for somthing else. What casting number heads do you have? 461, 462, 461X or 041 ? Al
Al
I have the 461 heads, and they are even a real good date to match my build. They are cast about 25 days before my car was built. Same for the carb and intake but I am going to use an aluminum intake. I have either an aftermarket one for the Vortec heads or a stock 69 Z28 intake if I use the 461 heads.
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1966 Strato Chief 2 door, 427 4 speed, 45,000 original miles
1966 Grande Parisienne, 396 1 of 23 factory air cars
carl, i've built a '75 400 (ya, CHEVY) with '97 305 vortec heads for this '69 impala. other than the aforementioned appearance issue, they're the best way to go. the 305 heads have a 58cc chamber, compared to the 350s 64cc chamber. as john said earlier, you're limited to about .480 valve lift before you have to machine the v/guide for clearance. the only problem is the temp sender hole is smaller than the '69 sender...
Dave
Do you happen to know what compression 58cc would be with the stock 327 pistons for 65? I suspect it may be a bit high for my liking. I am trying to get it in the 9.5 range, not really much higher. I want this to be a totally friendly combination, driveable, no worries.
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1966 Strato Chief 2 door, 427 4 speed, 45,000 original miles
1966 Grande Parisienne, 396 1 of 23 factory air cars