Single plane intake manifold

[ZRCTION]

496 bbc, 9.5:1 comp, oval port heads have'nt decided on a cam yet but it will be a big nasty flat tappet solid lifter from Clay Smith. I was curious what single plane intake works best? Single 4 barrel Holley 850cfm. I see the Victor is used alot but what about the Team G? Any others?

[DelawareDave]

Dart.
I wouldn't hesitate to use either of your choices, or the dart, except the issue of your oval port heads, and the availability of your manifold of choice to match them. I don't know if you could port match a rectangle intake to an oval port head.

[Sleeper CP]

What's your RPM range?
Sleeper CP
Big Inch Ford Lover

[cstraub]

I just so happen to have a Oval Port Dart single plane that was going on a 496CID project. If your interested let me know I am willing to part with it.

[ZRCTION]

What's your RPM range?
Sleeper CP
Big Inch Ford Lover
? probably upwards of 7-7500rpm. Rock solid bottom end, still deciding on a cam. I just know I want to get rid of the air gap dual plane intake I have now.

[cstraub]

? probably upwards of 7-7500rpm. Rock solid bottom end, still deciding on a cam. I just know I want to get rid of the air gap dual plane intake I have now.
You'll will then need a single plane..

[cfm]

Very hard to beat the Dart Oval Port Single Plane Intake. Especially if you are dropping it in as cast out of the box. Well worth the extra $100 over the other manufacturers intakes.
I'd still use this in your application even if you where building a mild 5500 rpm motor.
I hope your oval ports are atleast mildly ported by a Professional

[Fired Up]

I have a Holley Strip Dominator (large oval port)for a BBC that I ran with my big oval port heads and 850DP if you are interested. PM me if you have any questions. .

[Sleeper CP]

? probably upwards of 7-7500rpm. Rock solid bottom end, still deciding on a cam. I just know I want to get rid of the air gap dual plane intake I have now.
Stout. What are you putting it in?
Sleeper CP
Big Inch Ford Lover

[bradbigsley]

7-7500 rpm with a single holley 850?

[Sleeper CP]

7-7500 rpm with a single holley 850?
Good question :D
496x7500(rpm)=3,720,000/3456=1,076(cfm)
1,076 x 1.1(ve of 110%) = 1,183 cfm required by a 496 at 7,500 rpm's.
Sleeper CP
Big Inch Ford Lover

[SmokinLowriderSS]

7-7500 rpm with a single holley 850?
As much as I am the pain in the arse guy who seems to always think everyone with an 850 on a 454 jet-boat is overcarbing, An 850 on a 500" motor at 7-grand is a pretty drastic UNDER carb IMO.
I'm with brad & sleeper on this one.

[jungledave]

496 bbc, 9.5:1 comp, oval port heads have'nt decided on a cam yet but it will be a big nasty flat tappet solid lifter from Clay Smith. I was curious what single plane intake works best? Single 4 barrel Holley 850cfm. I see the Victor is used alot but what about the Team G? Any others?I am no expert on chevys but are you using an oval port head like a 353049 or 990 head? I was told that a 454-468 is as big as you should go on a factory oval port head and that they would not make good power after 5500 RPM. Shoudn't a 496 have square port heads on a 7000 RPM motor. I am running 049 ported heads on my 454 with the performer RPM air gap intake. I really like the perforamance of the intake. Like I said I am no expert and have learned quite a bit off this site:)

[steelcomp]

If you really want this thing to run right, get the heads flowed. I think you'll find that you're going to be a little on the shy side of what you need for a 496 turning 7000+ (ported by a pro, you'll have a better chance, but still going to be shy) although with a good roller, you might get there. I don't think you'll do it with a flat tappet, though. With a single four, an 850, and that oval port Dart, you'll have some serious throttle response, that's for sure, but I'm thinking it'll be done by 6000, maybe a little more. Of course, if you want to spend a lot of $$ and get really trick with long rockers, custom grind, trick porting, big valves, mucho compression, light weight rotating assy, etc.....:idea:

[steelcomp]

Good question :D
496x7500(rpm)=3,720,000/3456=1,076(cfm)
1,076 x 1.1(ve of 110%) = 1,183 cfm required by a 496 at 7,500 rpm's.
Sleeper CP
Big Inch Ford LoverI don't think you'd never see 110% ve on this build.

[steelcomp]

Dart.
I wouldn't hesitate to use either of your choices, or the dart, except the issue of your oval port heads, and the availability of your manifold of choice to match them. I don't know if you could port match a rectangle intake to an oval port head.The mismatch isn't as big a deal as you'd think. Certainly not worth the effort to make a rect. port fit the oval. The air will pack against the exposed intake surface on the head (going into the port) and form it's own boundry layer, actually providing for a fairly smooth transition. More important would be the plenum volume and runner entry size and shape to feed the engine. I think (not sure, though) the Dart is a rect port intake that they reshaped the runners down stream, so it probably has all it needs in the plenum/entry area. The velocity on a 496 at 7500 with this inatke on stock ovals (at the choke) is probably very high. Even though this is an oval port intake, I'm pretty sure it was designed to work with Dart's oval port Merlins or something similar, which flow better than 990's.

[Sleeper CP]

I don't think you'd never see 110% ve on this build.
9.5:1 and flat tappet you are correct.
On our old 512 w/ 10.17:1 and a custom roller saw 112% at 6,000. I was figuring if he is building it to turn 7,500 it better be trick.
Sleeper CP
Big Inch Ford Lover

[GofastRacer]

I don't know if you could port match a rectangle intake to an oval port head.
I did it once with 049's and an Edelbrock TR2X tunnelram, it worked but all I got was 2mph out of it, and I'll tell ya this I would not do it again, 2mph ain't worth all the hours to get that 2mph!...

[Sleeper CP]

I'll tell ya this I would not do it again, 2mph ain't worth all the hours to get that 2mph!...
Oh what kind of hotrodder are you,:( I know guy's that would give up body parts for 2mph;):D
Sleeper CP
Big Inch Ford Lover

[steelcomp]

9.5:1 and flat tappet you are correct.
On our old 512 w/ 10.17:1 and a custom roller saw 112% at 6,000. I was figuring if he is building it to turn 7,500 it better be trick.
Sleeper CP
Big Inch Ford Lover
For that set up to turn 7500, it'd HAVE to hit 110%+. That's basically my point. It won't.

[steelcomp]

Oh what kind of hotrodder are you,:( I know guy's that would give up body parts for 2mph;):D
Sleeper CP
Big Inch Ford LoverLOL...yeah, no doo doo.

[GofastRacer]

Oh what kind of hotrodder are you,:( I know guy's that would give up body parts for 2mph;):D
Sleeper CP
Big Inch Ford Lover
Yeah when run out of rope, but when you can just bolt something else on and get 5-10mph, 40hrs ain't worth 2mph!...:rolleyes:

[cfm]

I don't think you'd never see 110% ve on this build.
Agreed, but.....
That's actually a decent % to use for carb sizing on a single plane intake. I like to use 110%-130% on single planes and around 130-150% on dual planes. The larger % for engines with great heads/ good compression / modern cams / good modern intake.

[Sleeper CP]

Agreed, but.....
That's actually a decent % to use for carb sizing on a single plane intake. I like to use 110%-130% on single planes and around 140-150% on dual planes. The larger % for engines with great heads/ good compression / modern cams.
Educate me on this.
Do you mean dual carbs, or dual plane:confused:
If someone is running a 540 at 7,000 rpm's my math shows 1,094. If I multiply that by a VE of 150% I get 1,640 cfm's. So that's a "minimum" of 1,640 cfm's to achieve the full potential (?) from the engine. But a built 540 at 7,000 can certainly use two 1,050's or 1,100's couldn't it:confused:
Or would you recommend two 950's for that combo?
Just asking . Thanks
Sleeper CP
Big Inch Ford Lover

[cfm]

Thanks for replying, made me notice a typo I made in my last post above.
I meant 130-150% (not 140-150%) on dual planes. Yes, dual plane intake manifolds.
BTW: a stock or low performance or old outdated dual plane does not really conform to this. I'd stay same as single plane of 110-130% on those.

[ZRCTION]

? probably upwards of 7-7500rpm. Rock solid bottom end, still deciding on a cam. I just know I want to get rid of the air gap dual plane intake I have now.
Sorry for the typo. Its going to be a 468. George at Clay Smith is doing the build, he is calling the shots and says the dart intake should be fine for what i'm doing. He said today the cam should be around a 620 lift.
the engine is going in a 75' Hallett Baron Sprint with 15 over gears and a 11.5x14 prop. hoping for 500 or so hp. we'll see. Just making it loud quick lake boat:D
I am very interested in the Dart intake, is it going to fit a standard deck od is it for a tall deck?

[cstraub]

The Dart intake, that I have, is for a 9.800" Deck.

[Sleeper CP]

468@7,000-7,500@500HP=:(
Even at 9.5:1 you can get way better than that. Make sure you use a good set of heads on that thing. It will pay dividends.
Sleeper CP
Big Inch Ford Lover

[ZRCTION]

The Dart intake, that I have, is for a 9.800" Deck.
:confused: :confused:

[ZRCTION]

468@7,000-7,500@500HP=:(
Even at 9.5:1 you can get way better than that. Make sure you use a good set of heads on that thing. It will pay dividends.
Sleeper CP
Big Inch Ford Lover
Heads will come later. Kind a shot my budget on the bottom end. I think this boat will be plenty for now, just getting started with my first v-drive flatty.

[cfm]

Anybody else lost on this build or am I just having senior moments ?

[GUGS102]

I have a 489 with ported 049s and a .622/246 silgle pattern solid roller. I am running a air gap dual plane on it currently. It's in a jet so right now I am only turning 5200 at 76MPH. I know, I know, leaving a bunch on the table.
That is what the bottle is for. I have a dart oval port and have not tried it yet. I was told not to bother until I start spinning it over 5500.
Maybe I'll try the single plane and see what it does.
No expert either but that is a lot of weight to spin with a flat tappet. I'd say spend for the solid roller set up now, you can reuse all of it and sell the cam for one that matches your heads down the road. Come one, what's another $1000 for the short block.:D

[Sleeper CP]

Anybody else lost on this build or am I just having senior moments ?
;) :confused:
Sleeper

[steelcomp]

I have a 489 with ported 049s and a .622/246 silgle pattern solid roller. I am running a air gap dual plane on it currently. It's in a jet so right now I am only turning 5200 at 76MPH. I know, I know, leaving a bunch on the table.
That is what the bottle is for. I have a dart oval port and have not tried it yet. I was told not to bother until I start spinning it over 5500.
Maybe I'll try the single plane and see what it does.
No expert either but that is a lot of weight to spin with a flat tappet. I'd say spend for the solid roller set up now, you can reuse all of it and sell the cam for one that matches your heads down the road. Come one, what's another $1000 for the short block.:DNo reason to run a dual plane on a jet. That Dart will be an upgrade for sure.

[steelcomp]

Anybody else lost on this build or am I just having senior moments ?
LOL...what build? :jawdrop: :)

[cfm]

Sleeper and Steel - thanks. I was starting to feel as old as I look. LOL.
ZRction - for anyone to help you correctly we need as much 100% fact as possible. One little piece of misinformation or even a typo can lead you down the wrong path of 'bad suggestions.'
GUGS102 - With that cam + cids I'd put that Dart on there. Add to that, with plate nitrous systems I'd much rather have that single plane on there. Dual plane intakes have much larger fuel distribution inconsistencies. Also, if you can raise the rpm of that engine by another 500-700rpm or so it should really pull hard.

[River Rat 005]

I have a 489 with ported 049s and a .622/246 silgle pattern solid roller. I am running a air gap dual plane on it currently. It's in a jet so right now I am only turning 5200 at 76MPH. I know, I know, leaving a bunch on the table.
That is what the bottle is for. I have a dart oval port and have not tried it yet. I was told not to bother until I start spinning it over 5500.
Maybe I'll try the single plane and see what it does.
No expert either but that is a lot of weight to spin with a flat tappet. I'd say spend for the solid roller set up now, you can reuse all of it and sell the cam for one that matches your heads down the road. Come one, what's another $1000 for the short block.:D
I have a .030 454 with a similar cam. I took off a Weiand dual plane and put on the dart oval. I picked up 300 rpm. Went from 5500 to 5800.

[GUGS102]

I have a .030 454 with a similar cam. I took off a Weiand dual plane and put on the dart oval. I picked up 300 rpm. Went from 5500 to 5800.
That is a great gain. At roughly 20hp per 100rpm. 60Hp for an hours worth of work. Where do I sign up?
Maybe I'll get a fire under my rear and run it Sat morning as is, then change it out and run again. I'm only 20 minutes from the lake, that would make a good lunch break.
Other difference is the density altitude between last I ran it (Labor Day) and now. At that lake 2700ft and 100+ degrees it ran 73 at 5000.
Here in phx same combo ran 76 at 5200. At the river it runs 77-78 at about the same RPM (too little to make a clear distinction)
These are all based on my in dash GPS with recall button (what a cool toy that is)

[cfm]

Don't get too excited, or as excited, yet. He said Weiand dual plane without mentioning the model. If an Action Plus, that would totally explain it. If he said Stealth than this is more comparable, but not quiet as powerful as the Air Gap RPM.
The new this year Weiand Stealth Air Strike intakes are every bit as powerful as the Air Gap RPM's.