Low Profile Single Plane Intakes

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Valiantjim

Valiantjim

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So here's probably an uncommon request. I'm looking for legit experience with low profile single plane intakes on hot smallblocks. Why? I'm playing with the concept of how far I can push "273 Commando at a glance" subterfuge. I'm not a racer anymore but want to pop the hood of my 66 Valiant V100 and relate the look to the Commando label.

I'm using a 1990 roller cam LA block and have both a pair of worked 308 heads with 2.02 intakes and a set of Indy 360-1 aluminum heads. On the exhaust side I have 68-70 hipo 340 manifolds that I figure to apply the highest flow single exhaust possible. Still haven't finalized quench piston 360 or flat-top 408. The intake needs to look as much like a flat single plane 273 4bbl as possible. I include consideration of a stock intake, Extrude Honed with 4-hole plenum milled open, and any aluminum aftermarket shape that looks similar. I even have an Offy dual-port single-plane and a Holly Streetmaster on the shelf. This is all about a sub-2800# Valiant using a low first gear 904, 2.76 gears and as much motor as I can make look like a 273 Commando. Street driver with an unlikely looking old man behind the wheel...

I appreciate any input from anyone who's actually worked with low profile single planes across race/street/displacement variations.
I get that many have theories and opinions, as I do. I'm really looking for hard data from folks who applied real parts on real motors in real cars.

Thanks!
 
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I've used the Street Dominator on several engines across different makes on the street and strip and was always happy with them. Very surprised with the amount of bottom end torque they still have even though they are a single plane.
 
Holley Street Dominator or Edelbrock Street Master? The Holley Street Dominator is very close height wise to the stock 273 four barrel intake. I would run the Street Dominator with the 360 with 2.02 308 heads. If you ran the 408 360-1 head combination and wanted the somewhat stock appearance, I would run an Edelbrock Torker II and would see about having it ported. It's probably the largest single plane your'e going to find that resembles a stock intake.
Torker II 340/360 Small Block Chrysler Intake Manifold
Either way, that whole affair of a high geared lightweight car sounds like a whole lot fun, even more so with a 408 dressed to look like a 273 Commando!
 
The Torker II has caught my eye already, and no doubt the runner profiles are similar to the factory intake. My bias is definitely towards the 408/Indy option. For sure, the expected 400+ HP outcome in a light Valiant is fun to ponder. I've run some really hot A-bodies but am now in the mind of a basic stock looking Valiant. Driving around in an obvious race car is no longer age-appropriate for this driver. In fact, I think I may be about to have more fun than ever! Thanks for the quick responses and I'm definitely open to anyone else's input.
 
This looks similar to a factory 273 4v.

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Since you are running large port heads, I'd go with an Offy Port-O-Sonic. With some mods, they were recommended for Super Stock class racing. They will not limit your rpm either. Not that a 360 needs rpm. An Offy 360 intake also comes in a large port that looks similar to a factory 273 Commando intake. I'm contemplating a 273, 1.88 "J" head build using the Port-O-Sonic, factory exhaust manifolds, and Commando straight thru single exhaust.
 
Street master 318. Low profile and looks like a cast iron 273 piece if painted.
Any LA engine painted international tractor red with factory 273 valve covers and the chrome tin hat will fool 90% of the average folks.
 
Aren't truck 5.9 Magnum manifolds a easy swap with lots of flow?

The Offy Dual port may choke your engine. I have a 318 sized one I bought from Summit back in 2000 or so on my '79 360 van. The big port 340/360's were out of production. It worked well with the Comp RV grind and 2200 stall converter. It was done at 5000rpm in a 6500lb shoe box. Is your's the 360 size? It's an MPG/torque intake.
 
Another vote for the Holley Street Dominator. The Streetmaster looks VERY stock too, but one look at the 318 sized ports and plenum bottleneck would rule it out for anything bigger than a 273/REALLY mild 318 build.
The Torker II looks like a good possibility, but I've never used one so I can't comment on it. But I would beware of the later issued ones that have an offset thermostat- that would also kill the look, especially if using the correct Commando-era T-stat housing.
I like the 308s for this build, as the aluminum Indy heads would kill the Commando look almost immediately.
 
The Holley Street Dominator is good, but it has 273/318 intake ports. If running 340/360 intake port heads, I would use a 340/360 port intake manifold.
 
I like the Port-O-Sonic for the larger cubic inch build, too. The 360 variant would have a little better bottom end grunt with the street dominator for the 2.76 gears. But I don’t think that’s going to make a lot of difference with that light of a car.
 
I have an almost NOS PortOSonic for the 4V 351 Cleveland and it's a bad lookin beeotch. I would call it more of a mid rise intake, though. It's taller than the Street Dominator.
 
RustyRatRod said:
I have an almost NOS PortOSonic for the 4V 351 Cleveland and it's a bad lookin beeotch. I would call it more of a mid rise intake, though. It's taller than the Street Dominator.
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That Port-O-Sonic is kind of a ‘tweener intake. It falls between the Street Dominator and the Strip Dominator.

Ive always wanted to try one of those but never have.
 
Rat Bastid said:
That Port-O-Sonic is kind of a ‘tweener intake. It falls between the Street Dominator and the Strip Dominator.

Ive always wanted to try one of those but never have.
Click to expand...
Buy my Cleveland and you can try one. lol
 
I'll Do $10!
:lol:
Sorry, I couldn't resist! I wouldn't take it if it were given to me to have to use at the present, too much to do and keep up with and not enough $ to even do that...
 
If you could get the dividers cut out of the Offenhauser dual port, it would probably come on looking closer to stock than any of the other intakes. That would be pretty labor intensive to do, though!
 
Garrett Ellison said:
If you could get the dividers cut out of the Offenhauser dual port, it would probably come on looking closer to stock than any of the other intakes. That would be pretty labor intensive to do, though!
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Isn't the dual port the same as the 360*?

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