LS vs old school Opinions

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Glocktogo

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I think it's all a matter of application. If I was building an old school hot rod, I think there's something to be said for doing a flathead. Period correct muscle car? An OHV pushrod V8 is the way to go. Restomod? Definitely an LS motor of some kind. But even the LS is just a dressed up, old school OHV pushrod V8 with modern engine management. The Northstar OHC engines never got off the ground because of the issues they had, not because the concept is unsound. Ford's Coyote 5.0L is inch for inch, one of the best NA V8 engines ever produced, OHC or otherwise. Getting 460/420 with a 7250 redline is impressive to say the least (and a lot of people think it's underrated at those numbers. By comparison, the new LT1 requires almost 25% more displacement to be in the same HP/TQ range (455/455), with about 25% less rpm range, even with VVT.

There's just no disputing that each modern V8 engine advancement has allowed us to get more power per inch, but that doesn't mean the old school stuff is obsolete. It just means the application should fit the expectations you have for it! :)
 

DaveinOKC

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What else you doing to your LS you keeping FI.
What kind of 69 and what cam etc. You keeping stock lifters and springs?

It is for my 69 Camaro with full Speedtech Suspension, 14" Wilwoods and T56 Magnum. Right now looking at a BTR Positive Displacement Stage III Supercharger Cam. Although there are a couple of other options I am considering. Definitely replacing the springs, not certain on the lifters. I will inspect them first and then decide if I want to upgrade to something like the LS7 lifters. I don't need anything ridiculous as the spring pressures will be kept to a minimum and will only be rev'ing motor to 6500-6700rpm. Other mods are an upper and lower pulley change for the supercharger, Flex Fuel Sensor to run E85, and larger fuel injectors. If I don't meet my power goals, I will likely have the LSA supercharger ported rather than install a different supercharger. The LSA supercharger while small, is very efficient.

David
 

ripnbst

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LS motors are all the rage right now for a reason. If old carb'd motors had merit you'd still see them. People are swapping LS based motors into everything. If I was swapping an LS into something it would likely be the motor out of the C6 Z06 Vette. More costly up front sure but it will make gobs of power with just bolt ons.
 

swampratt

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My buddy James did the 6.0 LS with RPM intake and 750 cfm carb.
It is in a long bed truck with 3000 stall and 340 posi track rear gear.

Now something we noticed is the carb needed to be set up pretty fat to run happy with the setup.

Think about this Aluminum heads that have 210cc runners (a moot point on runner size really we do not know how long it is to make a fair comparison to old school heads.)
This head runs much cooler than an iron head.. The carbed intake sits way above a sealed off lifter valley so NO HEAT is introduced into the runners.
This is one reason we had to jet this carb fat... it was stumbling and falling on it's face even during a situation of easing slowly into the throttle.

Now the swap was done in the winter time and it was in the 40's outside and 20 minute drive would still not be enough to make it clear it's throat .
At wide open throttle after it recovered it ran really strong.

Or when ambient temps get into the 70's it runs very well.
This carb swap deal needs something to heat the runners.

Now I did experience the same situation with a tunnel-ram on iron heads with an old school build but after 10 minutes of driving the tunnel-ram would have enough heat in it even in sub freezing temps to allow it to act correctly.

Those dyno tests in a dyno cell do not account for real driving conditions.

I am all for carbs but When there are issues like we experienced with the 6.0 it gets lame.
Yes I have a cure.
I told my buddy we could make a sheet aluminum cover that encased the intake and held the heat that the lifter valley emitted.
Would look like crap but may have worked.

He did not want to try it as he is all about looks.
 

doctorjj

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My buddy James did the 6.0 LS with RPM intake and 750 cfm carb.
It is in a long bed truck with 3000 stall and 340 posi track rear gear.

Now something we noticed is the carb needed to be set up pretty fat to run happy with the setup.

Think about this Aluminum heads that have 210cc runners (a moot point on runner size really we do not know how long it is to make a fair comparison to old school heads.)
This head runs much cooler than an iron head.. The carbed intake sits way above a sealed off lifter valley so NO HEAT is introduced into the runners.
This is one reason we had to jet this carb fat... it was stumbling and falling on it's face even during a situation of easing slowly into the throttle.

Now the swap was done in the winter time and it was in the 40's outside and 20 minute drive would still not be enough to make it clear it's throat .
At wide open throttle after it recovered it ran really strong.

Or when ambient temps get into the 70's it runs very well.
This carb swap deal needs something to heat the runners.

Now I did experience the same situation with a tunnel-ram on iron heads with an old school build but after 10 minutes of driving the tunnel-ram would have enough heat in it even in sub freezing temps to allow it to act correctly.

Those dyno tests in a dyno cell do not account for real driving conditions.

I am all for carbs but When there are issues like we experienced with the 6.0 it gets lame.
Yes I have a cure.
I told my buddy we could make a sheet aluminum cover that encased the intake and held the heat that the lifter valley emitted.
Would look like crap but may have worked.

He did not want to try it as he is all about looks.
For decades people have worked to get cooler and cooler intake charge temps because this obviously leads to more power but you want to heat up the intake?? I think you just need a good person to tune it. Do you own a wideband?
 

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