454 High-Compression Engine setup
Thread Starter
5th Gear
Joined: Jan 2019
Posts: 5
Likes: 0
454 High-Compression Engine setup
hello guys, I'm new here in the forum 
I'm from Switzerland and last year I bought a big block of 73. A great car.
Now I want to increase the performance. The engine was completely overhauled 5 years ago, all original.
Now I want to change the cylinder heads and the camshaft in the first step.
I have seen the Edelbrock Performer High-Compression 454-O heads, I already have a Victor Junior Intake. Can you recommend the setup and what kind of camshaft should I use?Thank you for your answers and sorry for my bad English.
greetings from Switzerland
I'm from Switzerland and last year I bought a big block of 73. A great car.
Now I want to increase the performance. The engine was completely overhauled 5 years ago, all original.
Now I want to change the cylinder heads and the camshaft in the first step.
I have seen the Edelbrock Performer High-Compression 454-O heads, I already have a Victor Junior Intake. Can you recommend the setup and what kind of camshaft should I use?Thank you for your answers and sorry for my bad English.
greetings from Switzerland
Race Director
Joined: Aug 1999
Posts: 18,126
Likes: 174
From: WI
hello guys, I'm new here in the forum
I'm from Switzerland and last year I bought a big block of 73. A great car.
Now I want to increase the performance. The engine was completely overhauled 5 years ago, all original.
Now I want to change the cylinder heads and the camshaft in the first step.
I have seen the Edelbrock Performer High-Compression 454-O heads, I already have a Victor Junior Intake. Can you recommend the setup and what kind of camshaft should I use?Thank you for your answers and sorry for my bad English.
greetings from Switzerland
I'm from Switzerland and last year I bought a big block of 73. A great car.
Now I want to increase the performance. The engine was completely overhauled 5 years ago, all original.
Now I want to change the cylinder heads and the camshaft in the first step.
I have seen the Edelbrock Performer High-Compression 454-O heads, I already have a Victor Junior Intake. Can you recommend the setup and what kind of camshaft should I use?Thank you for your answers and sorry for my bad English.
greetings from Switzerland
Thread Starter
5th Gear
Joined: Jan 2019
Posts: 5
Likes: 0
Race Director
Joined: Sep 1999
Posts: 11,360
Likes: 382
From: Plano TX
I have a '71 LS5 454. Basically the same engine.
The Edelbrock 100cc heads will give you about 1 ratio higher compression. Not enough to make it 'high compression', about 9.5:1 maybe. But that's if the deck is near zero which it won't be if it's factory. Mine was crooked from the factory so cylinders had everything between 7.5 and 8.2 compression.
I finally took the plunge and yanked the engine and had it decked. They saved the numbers (although the machinist had some choice words afterwards. it was not easy). I went with forged pistons with a small dome. With the Edelbrock heads I now have a true 10.15:1. For a cam I recommend this: https://www.summitracing.com/parts/l...0712/overview/
This is a hydraulic roller cam which means you'd also need some other things to make it work. Roller lifters as well as compatible valve springs and a timing cover with a cam bearing. Not cheap, but I'd only recommend hydraulic roller cams for street use these days as the risk of running a cam flat is too great. No fun chasing special zink-oil or messing with additives hoping they'll protect the flat tappet cam.
The Edelbrock 100cc heads will give you about 1 ratio higher compression. Not enough to make it 'high compression', about 9.5:1 maybe. But that's if the deck is near zero which it won't be if it's factory. Mine was crooked from the factory so cylinders had everything between 7.5 and 8.2 compression.
I finally took the plunge and yanked the engine and had it decked. They saved the numbers (although the machinist had some choice words afterwards. it was not easy). I went with forged pistons with a small dome. With the Edelbrock heads I now have a true 10.15:1. For a cam I recommend this: https://www.summitracing.com/parts/l...0712/overview/
This is a hydraulic roller cam which means you'd also need some other things to make it work. Roller lifters as well as compatible valve springs and a timing cover with a cam bearing. Not cheap, but I'd only recommend hydraulic roller cams for street use these days as the risk of running a cam flat is too great. No fun chasing special zink-oil or messing with additives hoping they'll protect the flat tappet cam.
Le Mans Master
Joined: Mar 2001
Posts: 5,738
Likes: 644
From: Lincoln, CA
I'm using the Edelbrock heads with this cam.
http://www.claysmithcams.com/bbc-454...x-of-6000-rpm/
Agreed on changing the valve springs.
http://www.claysmithcams.com/bbc-454...x-of-6000-rpm/
Agreed on changing the valve springs.
Thread Starter
5th Gear
Joined: Jan 2019
Posts: 5
Likes: 0
I have a '71 LS5 454. Basically the same engine.
The Edelbrock 100cc heads will give you about 1 ratio higher compression. Not enough to make it 'high compression', about 9.5:1 maybe. But that's if the deck is near zero which it won't be if it's factory. Mine was crooked from the factory so cylinders had everything between 7.5 and 8.2 compression.
I finally took the plunge and yanked the engine and had it decked. They saved the numbers (although the machinist had some choice words afterwards. it was not easy). I went with forged pistons with a small dome. With the Edelbrock heads I now have a true 10.15:1. For a cam I recommend this: https://www.summitracing.com/parts/l...0712/overview/
This is a hydraulic roller cam which means you'd also need some other things to make it work. Roller lifters as well as compatible valve springs and a timing cover with a cam bearing. Not cheap, but I'd only recommend hydraulic roller cams for street use these days as the risk of running a cam flat is too great. No fun chasing special zink-oil or messing with additives hoping they'll protect the flat tappet cam.
The Edelbrock 100cc heads will give you about 1 ratio higher compression. Not enough to make it 'high compression', about 9.5:1 maybe. But that's if the deck is near zero which it won't be if it's factory. Mine was crooked from the factory so cylinders had everything between 7.5 and 8.2 compression.
I finally took the plunge and yanked the engine and had it decked. They saved the numbers (although the machinist had some choice words afterwards. it was not easy). I went with forged pistons with a small dome. With the Edelbrock heads I now have a true 10.15:1. For a cam I recommend this: https://www.summitracing.com/parts/l...0712/overview/
This is a hydraulic roller cam which means you'd also need some other things to make it work. Roller lifters as well as compatible valve springs and a timing cover with a cam bearing. Not cheap, but I'd only recommend hydraulic roller cams for street use these days as the risk of running a cam flat is too great. No fun chasing special zink-oil or messing with additives hoping they'll protect the flat tappet cam.
I'm using the Edelbrock heads with this cam.
http://www.claysmithcams.com/bbc-454...x-of-6000-rpm/
Agreed on changing the valve springs.
http://www.claysmithcams.com/bbc-454...x-of-6000-rpm/
Agreed on changing the valve springs.
I think I will order the camshaft from Summit because the shipping to Switzerland works great here.
once everything is installed I give a feedback if it works
Melting Slicks
Joined: Oct 2008
Posts: 2,154
Likes: 69
From: Regina Sk Canada
I am thinking you should get rid of that intake for an RPM performer if your going with oval port heads and a hydraulic cam, this motor will be done by 5500-5800 rpm anyway. pick a cam in the .550-.585 lift and .245/.255 duration at .050
Race Director
Joined: Jul 2015
Posts: 13,082
Likes: 3,399
From: SW Florida.
Victor Jr is a great full-throttle intake. Drag car or high perf boat. You lose quite a bit of power from idle to 5k rpm, which is where it will spend all it's time. Check with edelbrock. Not sure which manifold, but they make a dual plane with ports that match those half-oval, half-rectangle heads.
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Race Director
Joined: Mar 2016
Posts: 14,305
Likes: 8,110
From: Napa Valley California
I went with the Edelbrock Performer RPM Air Gap.
Edelbrock recommended it for my 496, with the Edelbrock Performer RPM heads with oval ports.
They said it’s an almost perfect port match and will work best from idle through 6000 rpm’s.
I went with a Crane, HR 230/236, 590/610 with an operating range of 2000-5800 rpm’s which Crane told me will realistically pull through 6000 rpm.
I’ll be at 10.4 to 1 CR and a Quick Fuel Q-850 carb.
Edelbrock recommended it for my 496, with the Edelbrock Performer RPM heads with oval ports.
They said it’s an almost perfect port match and will work best from idle through 6000 rpm’s.
I went with a Crane, HR 230/236, 590/610 with an operating range of 2000-5800 rpm’s which Crane told me will realistically pull through 6000 rpm.
I’ll be at 10.4 to 1 CR and a Quick Fuel Q-850 carb.
Last edited by OldCarBum; Feb 2, 2019 at 06:48 PM.
Melting Slicks
Joined: Oct 2008
Posts: 2,154
Likes: 69
From: Regina Sk Canada
I went with the Edelbrock Performer RPM Air Gap.
Edelbrock recommended it for my 496, with the Edelbrock Performer RPM heads with oval ports.
They said it’s an almost perfect port match and will work best from idle through 6000 rpm’s.
I went with a Crane, HR 230/236, 590/610 with an operating range of 2000-5800 rpm’s which Crane told me will realistically pull through 6000 rpm.
I’ll be at 10.4 to 1 CR and a Quick Fuel Q-850 carb.
Edelbrock recommended it for my 496, with the Edelbrock Performer RPM heads with oval ports.
They said it’s an almost perfect port match and will work best from idle through 6000 rpm’s.
I went with a Crane, HR 230/236, 590/610 with an operating range of 2000-5800 rpm’s which Crane told me will realistically pull through 6000 rpm.
I’ll be at 10.4 to 1 CR and a Quick Fuel Q-850 carb.
Race Director
Joined: Mar 2016
Posts: 14,305
Likes: 8,110
From: Napa Valley California