Exactly which heads do I have?
09-17-2002, 09:46 AM
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Exactly which heads do I have?
I have a `98 7.4 MPI (310 hp). I am in the planning stages for future upgrades. I am not sure what cylinder heads this engine came with. I have been told it has the 454 "Vortec" heads. I have also been told it has the infamous "peanut-port" heads. I know the peanut-port heads are only good for tow-trucks. If I have the Vortec heads, will they respond well to porting and larger valves? Or should I just save up and buy some Merlins? I`m not looking for huge horsepower, but would like about 425 at the prop. One more thing...Which is a better head? The Vortecs or the early 70`s large oval-port?
09-17-2002, 11:35 AM
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I know that Valako (JimV) has done some peanut port heads with very good results. I guess you'd need to crunch the numbers to see which way is more cost-effective- having the heads modified or just buying aftermarket heads.
09-17-2002, 11:41 AM
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Originally posted by DonMan
Yes, I have seen that article in one of the hot rod magazines. He really woke them up.
Yes, I have seen that article in one of the hot rod magazines. He really woke them up.
Man, that article must be 10 years old! Good to know that I'm not the only one to memorize a magazine! lol!
09-17-2002, 03:08 PM
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DonMan reply
DonMan,
The heads you have are not the "peanut port heads" they are large oval port heads. The peanut port heads hold 200 cc's of volume and the BB Vortech heads hold 230 cc's of volume, the same as the early large oval port heads. The BB Vortech heads are superior to the early heads because they have a small vane in the intake port that induces swirl into the intake mixture as it enters the cylinder. The exhaust ports are improved D port designs that flow very well. The combustion chambers are high compression heart shaped that keep the fresh fuel mixture from exiting the exhaust valve on camshaft overlap. They are also good at adding swirl to the air fuel mixture. They tolerate high compression ratios with low octane fuel. The heads are an improved version of the old large oval port heads and are really something! They are the best engineered (not the highest flowing) big block cylinder heads available except for the new 496 engine.
You need to increase the camshaft lift and duration to improve the performance of your engine. This is a real can of worms with the EFI. Just for fun you should add a carb and cam and see how it goes. I bet you would be very pleased!
I wrote a very detailed article in the May 2002 FAMILY AND PERFORMANCE BOATING MAGAZINE on the big block Vortech heads.
See if you can find a copy, or order it from us at 805-986-0400.
By the way, Bob Carpenter, who writes for the magazine, is the same Bob Carpenter that used to write for Peterson Publishing/ CUSTOM CLASSIC TRUCKS he is really cool and laid back (typical of a native of southern caifornia) but gets a little uptight when I am driving the boat! (goes to show that race car drivers are wimps compared to us boat drivers!). Look for his daughter to be the next big tennis sensation from southern California!
Sincerely
Dennis Moore
The heads you have are not the "peanut port heads" they are large oval port heads. The peanut port heads hold 200 cc's of volume and the BB Vortech heads hold 230 cc's of volume, the same as the early large oval port heads. The BB Vortech heads are superior to the early heads because they have a small vane in the intake port that induces swirl into the intake mixture as it enters the cylinder. The exhaust ports are improved D port designs that flow very well. The combustion chambers are high compression heart shaped that keep the fresh fuel mixture from exiting the exhaust valve on camshaft overlap. They are also good at adding swirl to the air fuel mixture. They tolerate high compression ratios with low octane fuel. The heads are an improved version of the old large oval port heads and are really something! They are the best engineered (not the highest flowing) big block cylinder heads available except for the new 496 engine.
You need to increase the camshaft lift and duration to improve the performance of your engine. This is a real can of worms with the EFI. Just for fun you should add a carb and cam and see how it goes. I bet you would be very pleased!
I wrote a very detailed article in the May 2002 FAMILY AND PERFORMANCE BOATING MAGAZINE on the big block Vortech heads.
See if you can find a copy, or order it from us at 805-986-0400.
By the way, Bob Carpenter, who writes for the magazine, is the same Bob Carpenter that used to write for Peterson Publishing/ CUSTOM CLASSIC TRUCKS he is really cool and laid back (typical of a native of southern caifornia) but gets a little uptight when I am driving the boat! (goes to show that race car drivers are wimps compared to us boat drivers!). Look for his daughter to be the next big tennis sensation from southern California!
Sincerely
Dennis Moore
09-17-2002, 03:52 PM
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Thanks for the reply Dennis!
I realize how finicky the EFI is when installing go-fast parts...what a headache! I am just looking for a few more MPH out of the "little" 454 without going bankrupt. I have thought about swapping on a carb, but am afraid of killing my fuel consumption. It is really pretty respectable right now. When I get ready for the cam swap, I will get back to you on a recomendation.
I thought that was the same Bob Carpenter! Classic trucks are one of my other passions. Tell him to "lighten up", the white knuckles are a sure sign of a good time!
THANKS FOR THE INFO!
I realize how finicky the EFI is when installing go-fast parts...what a headache! I am just looking for a few more MPH out of the "little" 454 without going bankrupt. I have thought about swapping on a carb, but am afraid of killing my fuel consumption. It is really pretty respectable right now. When I get ready for the cam swap, I will get back to you on a recomendation.
I thought that was the same Bob Carpenter! Classic trucks are one of my other passions. Tell him to "lighten up", the white knuckles are a sure sign of a good time!
THANKS FOR THE INFO!
