PanGasket
has cork sides
are the ports really gonna be a huge issue and what kind of gaskets should I use, the 318 gaskets, or the 340/360 ones?
Edelbrock 7576 Air Gap on 318
- Thread starter PanGasket
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fishy68
Tyr Fryr's Inc.
There is a real big difference in the small 318 ports vs. the Eddy's 340/360 size ports. Will create a huge step for the air to try and jump over. Lots of turbulence. I'd never put one on small port heads. There are good small port intakes out there.
PanGasket
has cork sides
please direct me to one
SirDan
Well-Known Member
The ld4b is a great intake for a 318. the ld4b is supposed to be cast for the 318 small ports but when i yanked mine off it had big ports. so measure the port size before buying. It's an old school intake and you can't get a new one anymore. Probably one of the best manifolds out there with 318 sized ports.
I had the big port version on the small port 318. ran really good, would have ran better if it had the small ports.
I had the big port version on the small port 318. ran really good, would have ran better if it had the small ports.
Baxter61
Well-Known Member
Is this a stock 318? Or does it have higher comp, 340/360 heads, some cam and headers? A weiand action plus is a good choice for a stockish 318
fishy68
Tyr Fryr's Inc.
As SirDan mentioned the LD4B is a great intake. Another older intake that was very good was the Holley street dominator. It was a single plane intake which doesn't always lend itself well to a small cube engine but it was designed with small ports and plenum so it worked on the 318 real good. One thing to ask when buying a used intake is has anyone ground on it. Sometimes what people do to try to make something better isn't always a good thing so I generally pass on a modified intake unless they have very good pics of what was done or I know who I'm buying it from well enough to trust them. I've seen a couple for sale lately priced very reasonable so you might look in the for sale forum. If you can find one with the balance tube running across the back from the #7 to #8 ports I hear they work the best. I've only ran the style without the balance tube and they worked great for me.
PanGasket
has cork sides
I'm actually trying to buy new, but it seems like no one makes small port intakes new for the 318.
edelbrock performer is a small port intake
as for the airgap im probably the only one in the world that is not impressed by it, ports are way small compared to the gasketsize on a 340 and it may be a good performing intake but on my junk the holley stripdominator felt better and the old edelbrock tunnelram sure has alot more go.
PanGasket
has cork sides
I just don't wanna keep changing intakes. I wanna buy a great one and a nice mild cam and headers and be happy with what i boughtedelbrock performer is a small port intake
as for the airgap im probably the only one in the world that is not impressed by it, ports are way small compared to the gasketsize on a 340 and it may be a good performing intake but on my junk the holley stripdominator felt better and the old edelbrock tunnelram sure has alot more go.
fishy68
Tyr Fryr's Inc.
You might want to ask one of the engine builders on the board (Brian with IMM engines or Mike at MRL) what would be the best for you. I'm not familiar enough with the small port engines to know what there is new on the market.
OldmanRick
Well-Known Member
If you want to buy new, just get a Performer and be done with it. But, i've seen them used on the net at $100 or less. If they haven't been modified that would be a great deal for you.
fishy68
Tyr Fryr's Inc.
That's odd that you say that because a few yrs. back I port matched a Air-gap to a set of 68 X heads and had to take very little meat out to match it the heads. Now the gaskets were a different story as they come in various port sizes. The Fel-Pro gaskets I bought at that time had port windows quite a bit bigger than the X heads. I wonder if you might have got one that had a casting issue? I have only had 2 and both were fine but I read that some had issues.
LXguy
Well-Known Member
edelbrock performer is a small port intake
as for the airgap im probably the only one in the world that is not impressed by it,
Are you sure you were looking at an Edelbrock intake and not the Chinese knockoff POS?
They are very different.
DarTT
I like the Street Dominator also.
If you are going to upgrade to 360 heads or something later, I would just get the air gap now. Yes, the ports are bigger and it isn't going to be ideal, but it isn't like it won't run at all or something like that. If you really hate it then buy a small port intake and you won't be out anything, except some gaskets and elbow grease.
PanGasket
has cork sides
which gaskets should i buy for the air gap? small port or big port?
the performer is basicly the only one out there that you can buy new for the smallport engine except for maybe some offenhauser ,from my memory but i would think the performer is better,its not intended for a serious streetmachine set the world on fire type but will do good on the small ports with a nice and mild cam,the small ports keep velocity high and its low enough to fit under most any hood. had one on a 318 along time ago that with a edelbrock 600carb and a mild cam and some headers made for a nice daily driver 318 with enough power to make some smokeshows with some help form the brakes if i had done it today i would have used a edelbrock 500 ontop of it
this is unless you plan on getting heads with the bigger ports in the future then you might aswell get one with bigger ports straight away.
i never bothered to portmatch it since i figured i couldnt reach far enough with my short carbides to make a good diference, later this summer that manifold is going to leave the engine again,i will have a look thru my assortment of gaskets and do a comparison with diferent gaskets to make sure,my heads are pretty useless to compare with since they are matched to the biggest gasket i could find,and it has been years since that was done so i cant remember wich gaskets they where matched to by my friendly porting guy and this manifold is on the car for a simple purpose that is not related to powermaking anyway
yep its a geunine edelbrock piece,will have a good look at it the next time its of and compare to a few gaskets might be a factory oddball or something. and the lack of performance might in my case just be that it doesnt like my enginecombination wish i thould was a perfect combination for it
64physhy
Well-Known Member
I have an Offenhauser on my 273 and a Performer on the 318 that came out of my Duster. IMO, the performer is best for a 318. Good low-end torque. I've ran Performers on SBC's also, and think that it's about the best street manifold out there, especially on the lower CID engines.
For a mild 318 with 318 heads I would agree to go with the performer or action plus, or something close to those. If you had 340/360 heads I would say go for the air gap, or performer rpm.
Is your car an original 2 barrel or 4 barrel car if it's 4 barrel you have 360 heads anyway, I'd only with the rpm air gap if you plan on a more serious build down the road. Or dig up 360 intake little heavy works with all factory accessories and equal of better than lower end aftermarket intakes.
Unless he has some special import 318 from Mexico, they did not put 340/360 heads on 318s at the factory. The performer and others like it are not lower end intakes, they are just made to work with stock port sizes on 318 heads.
if you decide to use it use felpro 1213 gasket 0.60 thick
HemiMark
Well-Known Member
I just bought an LD4B from e-bay. Havent got it yet but I will report how it works. It's going on my sons 318.
Factory 4 barrel 318 cars had 360 intake and heads, Chrysler did the same crappy swap most of us make and wonder why its got no power. And the performer makes less HP than 360 stock intake I got one in the garage that my cousin gave me because it slowed his late model down even though weight is very important to those cars especially over the front tires. The ports on them are a compromise too small for 340/360 too large for 273/318.
DusterKrazy
Well-Known Member
Yes..they did. Chrysler started to offer a 4bbl in '78...that got you the 360 heads. There are a few police package cars equipped this way.
.....Ur 318 is gonna be pretty sad on the low end with an air gap intake.......I've seen police cars with 360 heads on 318s........but any cars or trucks i've had just had 318 heads on a 318 4 bbl............kim.....
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