LD4B intake

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jrc4y4

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Have a 1972 318 bored .030. 470 lift cam, Edelbrock Performer Intake, 600 CFM Eddy carb. 2800 stall. 2.76 gears (will swap to 3.55s eventually). Stock exhaust manifolds. Stock heads. MP electronic ignition.

I was thinking of switching to an LD4B intake as I found one locally. Eventually I want to put 302 casting heads and hi po exhaust manifolds on and figured I would swap an LD4B at the same time. Would it be worth spending the money for a new intake, or would the Performer do what I needed it to?

Driven on the street most of the time, some on the highway. Haven't raced at the track in years. Want to keep it street friendly but get more out of it so people are surprised by the 318. Any help is appreciated!
 
we replaced a performer with an LD4B on a stock 318 and it ran waaaayy better....

Go with the LD4B...
 
Ha, you commented on the other intake post too! Thanks for all the help! I may have to even swap it on just intake for intake then as it sits.
 
I'm not sure about the performer intake coil mount but the ld4b does not have one on the manifold. I'm about to put a ld4b on my 273 can't wait. Dustin
 
i don't know if there would be an improvement but i love the look of the LD4B....and LD340.
wonderful old time pieces!
 
I'm not sure about the performer intake coil mount but the ld4b does not have one on the manifold. I'm about to put a ld4b on my 273 can't wait. Dustin
Let us know how it works. Do you have a 4 barrel on now? Stock Hipo manifold?
 
if you like, the stock coil mounting bracket is a perfect offset fit on the passenger side firewall hump....
 
If you take the time to port match the performer intake they work really well. I have a performer 318 / 360 and home ported '81 smogger heads on the stock '81 318 bottom end in one of my cars. Has a mild cam and a TQ carb. Thing runs really strong. I thought the intake was not going to be that great but I see no limitations with it on a street build.
 
Unless you plan on porting the 302 heads and or milling you probably won't see much improvement for the money. Plus not saying don't swap on 340 manifolds but again dollar for hp increase is questionable 5-7 hp.

If you don't want to port EQ's would be better and even if you do there probably still better.
 
If you take the time to port match the performer intake they work really well. I have a performer 318 / 360 and home ported '81 smogger heads on the stock '81 318 bottom end in one of my cars. Has a mild cam and a TQ carb. Thing runs really strong. I thought the intake was not going to be that great but I see no limitations with it on a street build.

Ok good to know.
 
Unless you plan on porting the 302 heads and or milling you probably won't see much improvement for the money. Plus not saying don't swap on 340 manifolds but again dollar for hp increase is questionable 5-7 hp.

If you don't want to port EQ's would be better and even if you do there probably still better.

1 7/8 inch manifolds are on there more. 340 hi po and a 360 magnum (I believe) are 2 1/4 and 2 1/8 respectively. I would expect more performance gain than 5-7 HP, wouldn't you think?

What are EQs?
 
1 7/8 inch manifolds are on there more. 340 hi po and a 360 magnum (I believe) are 2 1/4 and 2 1/8 respectively. I would expect more performance gain than 5-7 HP, wouldn't you think?

What are EQs?

There's a manifold shoot out on a mild 360 (300hp) With 318/360/340 and magnum manifolds and there was 5 or so hp from lowest to highest flow which was a combo of 340 and magnum manifolds. Even shorty headers only added like 10 or so hp and full length was like 15-20 hp If I remember right.

EQ are decent price high flowing magnum type head can come in LA intake bolt pattern.
 
There's a manifold shoot out on a mild 360 (300hp) With 318/360/340 and magnum manifolds and there was 5 or so hp from lowest to highest flow which was a combo of 340 and magnum manifolds. Even shorty headers only added like 10 or so hp and full length was like 15-20 hp If I remember right.

EQ are decent price high flowing magnum type head can come in LA intake bolt pattern.

Ok wow. Yeah I'm hoping to get mine in the 350 crank HP range someday. Currently 200 HP at ground and 240 tq, so I figured 270 crank and 300 tq? Just a guess.

Do you have a link to the shootout? Would hate to waste time and money to gain minimal performance.

So EQ are aftermarket?
 
Ok wow. Yeah I'm hoping to get mine in the 350 crank HP range someday. Currently 200 HP at ground and 240 tq, so I figured 270 crank and 300 tq? Just a guess.


Do you have a link to the shootout? Would hate to waste time and money to gain minimal performance.

So EQ are aftermarket?

4bbl and headers and comps xe262h is said to make 282 hp on a stock long block.
Seems similar your might be losing 15-20 hp cause of manifolds.

So basically your looking to gain 80-90 hp that's a lot especially with manifolds.

273/318 heads stock are good to about 300 hp with reasonable cam and CR.
Basically if you slap on headers and bumped up your CR 1 point you'd be at 300 hp.

Head flow is what you need to gain the rest.
The rule of thumb is you can make 2 hp per cfm but for street cam and cr its more like 1.7-1.8 hp per cfm. About 30 cfm gain at around your cam lift. You can get there with less but you'll need more cam.
Plus your gonna need to make up for the lack of headers.

General numbers
1.88 valves good for 375 hp
2.02 or magnums 400 hp
EQ 450 plus hp

Can port out 273/318 heads to match if you have the ability but then still a waste to me cause you could port out these heads for more.

Yes EQ's are aftermarket some places call them other names. Eq is enginequest

Screenshot_20170715-151208.png
 
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After buying EQ bare heads, valves and springs etc only to need the guides honed and seats cut to assemble I'd advise to go with these heads already setup from a place like Hughes, bronze lined guides, valve job, springs installed for lift .around .540", ready to go for less than buying them bare and going the route I did. A better route for most outside of max efforts
 
4bbl,headers and comp 262 probably won't add anywhere near 90hp

I've seen you argue that point many times why won't it ?

There's basically only 4 things besides heads that make N/A power
1. carb/intake
2. cam
3. Exhaust
4. CR

So to me a stock long block has a hidden potential limited by stock heads and cr.
Lucky most stock heads leave a lot of room to grow from stock hp numbers. Except /6 Lol. That's why LS, modern hemi's and even a lowly magnum engine work well with a few bolt on's. And even 340/360 LA engines.
My magnum arguably picked up 100-130 hp with cam intake and headers. And a 5.2 magnum over a LA 318 made about 70 hp with basically a head swap.

318 heads have enough flow to make 350 hp if you go by that 2 hp per cfm rule. But I'd imgine you need a lot of cam (296 plus) and cr (13:1 plus) to squeeze those numbers out. But i find most engine are capable of 1.7-1.8 hp per cfm with streetable cams and cr. Which is 295-315 hp. So to get there you'd need to add a point of CR and go up a step or two on the cam ladder. So I don't see why 282 hp is so hard to believe.
 
My 1/4 mile dropped from 16.2x to 15.2x (slipping trans with 15.2x, blew next day lol) with the mods listed above. Still stock heads and manifolds. Guess that's about 100 hp ground, right?
 
your taking a lo compression 318 with small ports and valves,adding a 340 style cam and 4 bbl and making more power than a hi compression 340!
 
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