Help Me Choose An Intake!!!

[1976 Aspen]

I need a little help choosing an intake for my engine. It's a 1976 318 bored .030 over, zero decked, forged pistons, magnum heads milled .015 gasket matched, bowl ported and polished, TTI Headers, MSD Ignition, 10.33:1 compression, comp cams 280H, and the works. I have a 4.10 rearend with a 4 speed. I will be driving it on the street and the track also. I think I only have three options with those magnum heads. The single and dual plane M1 and the new Edelbrock Performer RPM Air Gap manifold #7577 The air gap is so new that summit or jegs doesn't have them yet. Any ideas where I could find one quickly? Or is that the manifold to have even? Any help would be appreciated. Thanks!!!

[dwc43]

It's not available for magnum heads just yet. It would not make a good street intake either. Since you went with this heads instead of some better ones, your stuck with using a M1 dual plane.

[rumblefish360]

1976 Aspen, I disagree with DWC 100% on this. If an intake is a must have now, go with the single plane intake. If you can wait, the RPM would be a better inatke for your engine.
I then suggest that you look to lighteing your car where you can. The front off the car would be the target area.
It's a stout cam in a 318 in a heavy car.
I can't see how the RPM wouldn't make for a good street intake.
I wouldn't be to thrilled running the single plane intake myself, but it would work OK.
The M-1 dual plane would be best for the street over the single plane, but you did say track.
Try Mancini racing for the intake?
http://www.manciniracing.com/

[1976 Aspen]

These heads are pretty cheap and they come complete with performance stainless valves and 1.6 rockers assembled for $600.00 Ported and polished they outflow the Edels. Anybody know when that Air Gap will be out? It's on the Edel website but I can't seem to find it anywhere.

[1976 Aspen]

Which out of the three would be the best?

[madscientist]

You said this is a 4 speed car with 4.10 gears right?? Skip the dual plane ANYTHING and find a single plane for it. With that gear and a stick you don't need to worry about bottem end.


M.S.

[dwc43]

Stick has nothing to do with needing more bottom end. The bottom end is need to get it moving and the more the better.

[drag-n-cuda]

1976 Aspen,
RPM Airgap would be the best choice if you can wait considering cam, gear, compression, etc.

my $.02,
drag-n

[1976 Aspen]

Now I'm confused!!!

[dwc43]

318's dont like big cams and start to loose botton end torque. It's better to stick with a dual plane on them and build for torque. The 340 makes good hp and hte 360 makes great torque due to more stroke so they can use single planes with very little trouble, but the 318 looses bottom end so a dual plane id much better for them.

[rumblefish360]

Now I'm confused!!!

So am I after reading what you wrote here;

Anybody know when that Air Gap will be out? It's on the Edel website but I can't seem to find it anywhere.

I just looked at it 10 min.'s ago. Go look again.
The RPM intake comes in 2 flavors, standard and air gap. There being sold now. Try jegs.com or summitracing. etc... The RPM heads are out in 2 flavors. 1 for the 340 with positive deck piston and the other one is for standard engines up to a zero deck piston.
Seems like you were talking about the new Magnum heads there a second. There not ready to be sold yet. I'm not sure if the Magnum intake is ready ethier.

Truly, this is where it's at.

If an intake is a must have now, go with the single plane intake.

Because the M-1 dual plane will limit upper RPM power for sure.
If you can't get the RPM, and I don't know why you couldn't, unless it's the Magnum style, get it over the single plane.
This is because this intake does what Edel. claims. Low RPM torque while having the abilty to produce top end power like a single plane intake.

The M-1 dual plane would be best for the street over the single plane, but you did say track.

madscientist said it well, with 4.10 and a 4spd, the single plane will work.
I have a 318 in my car with a slightly smaller cam in front of a 4spd and 4.10's. It'll work. But if the car will see street duty, go RPM.
Being you have an extra gear over an auto trans, this will help acceleration. It beats having a high stall and all the works. (But thats me, a 4spd guy.)
With a comp cams 280H grind, bottom end torque is not really there with or without a daul plane. This cam is going to act bigger in a 318. With a power band rated @ 2500 start, in the bigger engines, wheres the low end power?

[1976 Aspen]

I am talking about the Magnum heads from 93-2003. Thats what I have on my car. I talked to Edelbrock this morning and they said late summer release on the air gap for the magnum heads. I ordered the M-1 single plane this morning. I'll get the air gap this fall if I don't like it. I should have a pretty broad powerband I think with the 280H. Don't you?

[rumblefish360]

2500- 6000+ RPM, yea. I'd say broad.

[FASTDARTCHESTER]

Aspen,

I have a combo similar to yours but with the '302 heads with 1.88/1.60's; ported and polished to the max. Compression is 9.3:1.

In my Dart it went 12.90's last season with an M1 DUAL plane. I bolted an Air Gap on over the winter and just tuned it in and there is no doubt it pulls harder. I'm guessin the car is 12.60-12.70 now. All data supports a 25-30 hp gain on a well modified engine.

That's my experience with it. I am really impressed.

TD