I also made the change from the performer to the ld4b and noticed a performance improvement
Well the distributor vacuum horn is really really close to the runner. makes timing difficult. when I upgraded to an MSD distributor i couldnt get the timing right. Removed the vacuum horn and was able to dial in the timing ( i must confess, I am not the best at doing the timing - I did get professional help - who couldn't get it done either before removing the horn)
Maybe that is part of the reason
did it on my 318 with 302 heads , ld340 was noticeably better, my experience anywayGood info! Curious to try ld48 and ld340 in a side by side comparison on a build I'm doing.
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I have managed to get an LD4B intake. Right now I'm using a 500 cfm Edelbrock. Do you think that's enough carb? Seems like a lot of people are using 600's. Haven't been able to try any engine work as It's getting some paint.View attachment 1715125457 The engine came out of a 66 Barracuda. The owner is a professional engine builder with a lot of racing experience. He's the one that recommended the LD4B so I'm thinking it should fit. Currently it's running an Edelbrock 500cfm carb on a cast iron intake.
who did u last race? 'cause they blew your doors off .....I have managed to get an LD4B intake. Right now I'm using a 500 cfm Edelbrock. Do you think that's enough carb? Seems like a lot of people are using 600's. Haven't been able to try any engine work as It's getting some paint.
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Looks good. A 500 should work good on a 273 build. I have a 600 Edelbrock on mine and it works well too. If you are going for more horsepower and like to mess with tuning, you could tune what you have or try a different carb. But saying that, you may only gain a little horsepower. May-be not enough to justify the time and money.I have managed to get an LD4B intake. Right now I'm using a 500 cfm Edelbrock. Do you think that's enough carb? Seems like a lot of people are using 600's. Haven't been able to try any engine work as It's getting some paint.
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And it might. The LD340 has bigger ports and a different port configuration.did it on my 318 with 302 heads , ld340 was noticeably better, my experience anyway
As I understand the LD4B manifold was designed for use on the 273 back in the 60's. Port sizes on the 273 heads are smaller than your 318. Just like everything else, manifold technology has advanced in the last 40 yrs. IMHO you'd be stepping backwards switching manifolds.
I don't think you will be disappointed. I just sold one today.I just picked up an LD4B. Because of this thread.
My 318 needs all the help it can get!
Yes they do work and for the haters, there are better manifolds out there I bet, but day in and day out, The LD4B is a great manifold. (as you well know) A friend built a fairly mild .030 over 440 with a custom grind Comp cam, warmed over stock heads, headers and a CH4B intake (like the LD4B) It made 497 horse and 520+ torque. And it fit under his fresh air hood without mods and pulls like a freight train.Call me crazy, but I run an LD4B that is port matched to my EngineQuest heads. The 408 makes 520+ hp on pump gas. I always wonder how much power I'd gain/lose by swapping on my Mopar M1 intake.