I need torque!
Thread Starter
Teching In
Joined: Feb 2009
Posts: 33
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From: Va Beach
I need torque! I am considering swapping an LS motor into my 72 Riviera but I need a combination that will provide me with the most bottom end torque I can get.
I want to stay NA because I'm on a budget and I'm not really looking to make more than 500 crank horsepower with all the accessories bolted on. The kicker is I would like more than 500 lb-ft of tq so I can get this 4400lb metal giant off the line. The reason for the swap is I want more power, reliability, smooth operation and economy than my Buick 455 gives me. I've never really seen a high torque low horse LS combo, but I would imagine the key would be higher cubes with heads that provide better flow at lower lift numbers. Any help or guidance would be appreciated.
I want to stay NA because I'm on a budget and I'm not really looking to make more than 500 crank horsepower with all the accessories bolted on. The kicker is I would like more than 500 lb-ft of tq so I can get this 4400lb metal giant off the line. The reason for the swap is I want more power, reliability, smooth operation and economy than my Buick 455 gives me. I've never really seen a high torque low horse LS combo, but I would imagine the key would be higher cubes with heads that provide better flow at lower lift numbers. Any help or guidance would be appreciated.
Look in the dyno section, plenty of cam only/heads cam cars are making REALLY good torque and about the horsepower you want. I'm personally slapping a turbo on mine as its about the same money for me (I'm a welder) as it is to do a cam and springs and such. I think a TR224 or TR228 is a popular and good cam with a lot of low end and an idle that wont take your fillings out 
TECH Enthusiast
Joined: Jan 2010
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From: REALITY
When you consider valve-timing events, you also have to consider all the other elements acting on the fuel charge and combustion gases in the cylinders. An earlier-closing intake valve starts building cylinder pressure sooner. This increases low-speed torque due to greater cylinder pressures, but it means that the engine is having to work harder to compress the charge. As previously explained, a later-closing intake can enhance top-end torque at the expense of low-end torque, but you can get most of the torque back on the low end with an increased compression ratio. What you look for is a cam profile that promotes increased cylinder filling with earlier intake opening so that the valve is farther off the seat during the early portion of the intake stroke. Then you want to delay the exhaust-valve opening as much as possible to take advantage of all the energy you can from the combustion process before you blow down the cylinder. A quick-opening exhaust valve is helpful here, but, again, there are trade-offs.
This combination builds good torque but tends to increase valve overlap at TDC. This is where the cam lobe separation angle takes control. The lobe separation angle is the angle between the peak of the intake lobe and the peak of the exhaust lobe expressed in cam degrees. Tighter lobe separation angles (less than 110 degrees) make more torque and horsepower, but, with more overlap, the engine experiences poor idle quality and high fuel consumption. Opening up the lobe separation angles (more than 110 degrees) broadens the power band while improving idle and part throttle characteristics. With these wider lobe separation angles, peak torque and power are generally reduced, but the engine becomes very smooth and drivable.
-By John Baechtel
This combination builds good torque but tends to increase valve overlap at TDC. This is where the cam lobe separation angle takes control. The lobe separation angle is the angle between the peak of the intake lobe and the peak of the exhaust lobe expressed in cam degrees. Tighter lobe separation angles (less than 110 degrees) make more torque and horsepower, but, with more overlap, the engine experiences poor idle quality and high fuel consumption. Opening up the lobe separation angles (more than 110 degrees) broadens the power band while improving idle and part throttle characteristics. With these wider lobe separation angles, peak torque and power are generally reduced, but the engine becomes very smooth and drivable.
-By John Baechtel
With this said you should pay attention to your cam... The cams with earlier opening and closing intake timing events will produce more torque generally example: 21X/22X or 22X/22X, or 22X/23X @ .050........ If you talking about producing more torque I would not get a super big, megadeath, weapons of mass destruction, killa type cam.... example: 24x/25X+ @.050... Now if you want to broaden the torque curve or power curve you can by retarding the cam in essence running a 114-117 LSA vs a 110-112.... You will just be moving or delaying the torque to a higher rpm...... But advancing the cam and running a tighter LSA 110-112 should provide more low end torque.. Adv and retarding are ways to play with the torque curve and powerband....
Also your exhaust system, plays a roll... Maybe look into some longtube headers.....
Also when looking at heads, I would not suggest heads that are heavily ported with only a large concentration on flow cfm at .500,.600 lift... But flow well throughout the .200,.300,.400, range which is where more time is spent with typical driving..... you want the smallest port with the highest flow possible.....
Last edited by bozzhawg; Jun 2, 2010 at 10:31 AM.
Thread Starter
Teching In
Joined: Feb 2009
Posts: 33
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From: Va Beach
With this said you should pay attention to your cam... The cams with earlier opening and closing intake timing events will produce more torque generally example: 21X/22X or 22X/22X, or 22X/23X @ .050........ If you talking about producing more torque I would not get a super big, megadeath, weapons of mass destruction, killa type cam.... example: 24x/25X+ @.050... Now if you want to broaden the torque curve or power curve you can by retarding the cam in essence running a 114-117 LSA vs a 110-112.... You will just be moving or delaying the torque to a higher rpm...... But advancing the cam and running a tighter LSA 110-112 should provide more low end torque.. Adv and retarding are ways to play with the torque curve and powerband....
Also your exhaust system, plays a roll... Maybe look into some longtube headers.....
Also when looking at heads, I would not suggest heads that are heavily ported with only a large concentration on flow cfm at .500,.600 lift... But flow well throughout the .200,.300,.400, range which is where more time is spent with typical driving..... you want the smallest port with the highest flow possible.....
Also your exhaust system, plays a roll... Maybe look into some longtube headers.....
Also when looking at heads, I would not suggest heads that are heavily ported with only a large concentration on flow cfm at .500,.600 lift... But flow well throughout the .200,.300,.400, range which is where more time is spent with typical driving..... you want the smallest port with the highest flow possible.....
Teching In
Joined: Jan 2009
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From: North of Bagdad
Hitting this thread to see where you're at on the project. Thinking about doing the same with an earlier Riviera. Just wondering about the driveline being able to handle the strain if too much power is added. Like adding a D1SC or twin turbos.
