Twin turbo cam
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Twin turbo cam I have a .030 over 6.0 ls with a 4" dart crank. So a 408. It has cnc 823 heads and a Holley high ram. Turbo 400 with 3600 stall. I have been going back and forth on the tkm lamb cam and the btr 400+ medium twin turbo cam. I have a set of Turbonetics C15 78/75 billet bb turbos laying around. It's mostly street driving on e85 so I want a good sounding cam as well. Don't want a tractor sound. Which cam do you guys recommend? Thanks
Last edited by Glove; Apr 8, 2024 at 05:03 PM. Reason: Change in direction
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For a 370CID Twin Turbo that cam has too late an exhaust valve closing and too much overlap. I'm sure if you provide more info like vehicle weight, rear gears, turbo choices, exhaust setup, compression ratio, boost, fuel, and what your doing with the car (street, street/strip, strip only) then you'll probably get some better suggestions.
@Summitracing has a line of twin turbo specific camshafts. You're probably looking at the 8722R1 or 8723R1 depending on the answers to the above. https://ls1tech.com/forums/generatio...urbo-cams.html
@Summitracing has a line of twin turbo specific camshafts. You're probably looking at the 8722R1 or 8723R1 depending on the answers to the above. https://ls1tech.com/forums/generatio...urbo-cams.html
Last edited by 68Formula; Apr 1, 2024 at 08:43 PM.
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OP,
We echo what @68Formula is saying. That current cam is quite spicy for what we'd typically recommend. With more info on the combo and goals, the community could better serve you.
We echo what @68Formula is saying. That current cam is quite spicy for what we'd typically recommend. With more info on the combo and goals, the community could better serve you.
For a 370CID Twin Turbo that cam has too late an exhaust valve closing and too much overlap. I'm sure if you provide more info like vehicle weight, rear gears, turbo choices, exhaust setup, compression ratio, boost, fuel, and what your doing with the car (street, street/strip, strip only) then you'll probably get some better suggestions.
@Summitracing has a line of twin turbo specific camshafts. You're probably looking at the 8722R1 or 8723R1 depending on the answers to the above. https://ls1tech.com/forums/generatio...urbo-cams.html
@Summitracing has a line of twin turbo specific camshafts. You're probably looking at the 8722R1 or 8723R1 depending on the answers to the above. https://ls1tech.com/forums/generatio...urbo-cams.html
In my opinion at least... the whole appeal with a twin setup is to maintain 1:1 or better back pressure ratios. This means you cam the engine aggressively as if it were a max effort "NA cam". Meaning you make more power per pound in boost vs a low overlap "turbo cam".
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Huh... How exactly can you say the cam need less overlap when he didn't list the turbos he'd be running?
In my opinion at least... the whole appeal with a twin setup is to maintain 1:1 or better back pressure ratios. This means you cam the engine aggressively as if it were a max effort "NA cam". Meaning you make more power per pound in boost vs a low overlap "turbo cam".
In my opinion at least... the whole appeal with a twin setup is to maintain 1:1 or better back pressure ratios. This means you cam the engine aggressively as if it were a max effort "NA cam". Meaning you make more power per pound in boost vs a low overlap "turbo cam".
With twins it's true, one can spool a lot faster with bigger camshaft and more overlap, and it's easier to maintain good back pressure ratios; but there's still going to be a limit. The one he listed has a 52* IVC, and 14* ATDC EVC with 28.5* overlap, so regardless of the choice of turbos it would not be something one would want to use.
Yeah, no idea what turbos he has but just looking at the cam specs and intake being used that's like an 8000+ rpm setup assuming any sort of reasonable turbo setup.
I'm running a 252/260-116+4 with "small" 6870s on an LS7 based 427 and it runs out to 8200 rpms pretty easily, makes enough to trap 184 mph at 3400 lbs raceweight and there is still a few psi on the table.
I'm running a 252/260-116+4 with "small" 6870s on an LS7 based 427 and it runs out to 8200 rpms pretty easily, makes enough to trap 184 mph at 3400 lbs raceweight and there is still a few psi on the table.
