Intakes? Boost? And bears oh my!

[TT5.9mag]

I'd still vote dual plane for any kind of street motor. But I can also understand how the single is attractive from a fuel dist viewpoint.

Won't you have fuel dist issues anyway with a blow through, with that elbow on top?

You can with a junk tune up. But it’s not a definite.

Single 4 barrel, twin turbo, blow through, big inch, big hp. This is how the distribution on mine looks. It’s a lot of work to get it right but it’s worth it.

 

[Garrett Ellison]

As promised, some more single plane pics. First is an unmodified non EGR Holley Street Dominator. The port shape and window is close to stock 273/318 port size from the plenum to the flange. It would be a good intake for an RV turbo build.

 

[Garrett Ellison]

And then a Weiand 7545 Xcellerator with a Felpro 1243 hi-po 318 port size intake gasket. A little port matching work would go a long way on these intakes. But it’s a ver efficient fuller web intake design.

 

[Mean416]

Whatever the intake does NA will be replicated under boost. I doubt the old school intake will out perform the newer one in any respect.

 

[Garrett Ellison]

Whatever the intake does NA will be replicated under boost.

This exactly. Which is oddly enough why I posted the Street Dominator in case if it’s a 3.58 stroke engine.

Will be in a heavy W150 pickup.

Just because of this, I would be inclined to try it first if I went with a single plane.

I doubt the old school intake will out perform the newer one in any respect.

Since we are talking about a heavy vehicle, a performer air gap with a one inch spacer (a super sucker or a shear plate between that and the carburetor probably wouldn’t hurt anything either!) and the plenum divider milled one inch from the floor would probably have an advantage here. An air gap intake flows within 7cfm port to port, so fuel distribution shouldn’t be as much of a problem as speculated. The blow through design with a turbo makes for free after cooling. It makes sense to me to use an air gap to maximize that effect.
But, before we go much farther, a few questions about this probably 4500 plus pound 4X4…
What gears and tire size, and what cylinder heads? I’m under the impression that the cam specs are an unknown as of yet and as yet to be determined based on these factors.

 

[gagembassett]

This exactly. Which is oddly enough why I I posted the Street Dominator in case if it’s a 3.58 stroke engine.

Just because of this, I would be inclined to try it first if I went with a single plane.


Since we are talking about a heavy vehicle, a performer air gap with a one inch spacer (a super sucker or a shear plate between that and the carburetor probably wouldn’t hurt anything either!) and the plenum divider milled one inch from the floor would probably have an advantage here. An air gap intake flows within 7cfm port to port, so fuel distribution shouldn’t be as much of a problem as speculated. The blow through design with a turbo makes for free after cooling. It makes sense to me to use an air gap to maximize that effect.
But, before we go much farther, a few questions about this probably 4500 plus pound 4X4…
What gears and tire size, and what cylinder heads? I’m under the impression that the cam specs are an unknown as of yet and as yet to be determined based on these factors.

Yes sorry I've been lagging behind on my post with replies. The truck is heavy as stated. The tire size is 33 inches and i plan to swap to either 3.90s or 4.10s, cylinder heads will be lightly ported 308 heads, unsure if I will stay 1.88 or go 2.02 valves. The cam specs I will call Jim at Racer Brown this evening to see roughly what he thinks the specs will be

 

[TT5.9mag]

This exactly. Which is oddly enough why I I posted the Street Dominator in case if it’s a 3.58 stroke engine.

Just because of this, I would be inclined to try it first if I went with a single plane.


Since we are talking about a heavy vehicle, a performer air gap with a one inch spacer (a super sucker or a shear plate between that and the carburetor probably wouldn’t hurt anything either!) and the plenum divider milled one inch from the floor would probably have an advantage here. An air gap intake flows within 7cfm port to port, so fuel distribution shouldn’t be as much of a problem as speculated. The blow through design with a turbo makes for free after cooling. It makes sense to me to use an air gap to maximize that effect.
But, before we go much farther, a few questions about this probably 4500 plus pound 4X4…
What gears and tire size, and what cylinder heads? I’m under the impression that the cam specs are an unknown as of yet and as yet to be determined based on these factors.

Great post.



Here is holdeners test of dual planes on two different engines and two kinds of boost. You can see it does work. And the power curves do what dual plane intakes are supposed to do. But pay attention to the headers and 8 o2s on the LS. I honestly think this is the level of tuning it takes to keep one alive with a dual plane and boost. Tune tune tune.

 

[Garrett Ellison]

That’s okay Gage, there is life outside of the forum! How many pounds of boost are you going to use and what’s your present transmission and axle gearing?

 

[TT5.9mag]

I’ve recommended this on the forum before and I’ll do it again here. @gagembassett you should go to the junkyard and grab a magnum 5.9, throw a blow through carb, intake manifold, and a cam/springs in it, and boost. Use it as a learning tool and a sacrificial lamb to get the system worked out and learn to tune it. Most of the parts can be moved over to the new engine and the knowledge you get from tuning on an engine you don’t really care about will be well worth the effort. And it will easily make your power goal we talked about. Hell you might just leave it in there if you don’t kick the rods out.

 

[DNasty777]

I’ve recommended this on the forum before and I’ll do it again here. @gagembassett you should go to the junkyard and grab a magnum 5.9, throw a blow through carb, intake manifold, and a cam/springs in it, and boost. Use it as a learning tool and a sacrificial lamb to get the system worked out and learn to tune it. Most of the parts can be moved over to the new engine and the knowledge you get from tuning on an engine you don’t really care about will be well worth the effort. And it will easily make your power goal we talked about. Hell you might just leave it in there if you don’t kick the rods out.

This is what I'm doing. $500 for a 5.9 magnum at a pick-and-pull, put new bearings in it and gapped the rings. I'd rather learn on this junkyard motor and blow it up instead of my 408 rotating assembly and the associated block.

 

[a-bodyguy]

tests ive seen the street dominator on the sbm was worse then a factory intake i would never run it
with a blower you will have loads of torque thats 1 reason the cam shops go 112 or 114 lsa
single plane all the way you can afford a little less torque@3000
imo

 

[TT5.9mag]

tests ive seen the street dominator on the sbm was worse then a factory intake i would never run it
with a blower you will have loads of torque thats 1 reason the cam shops go 112 or 114 lsa
single plane all the way you can afford a little less torque@3000
imo

Can you link to the tests please.

 

[a-bodyguy]

Can you link to the tests please.

i believe member 273 posted and intake shootout with it
318willrun said it was slower then the stock intake

 

[Garrett Ellison]

I’ll agree that a street dominator is best for small port heads. They work best with 10:1 plus, a large cam, headers, 700 plus CFM carb, and low gears on a stock headed 318. But if using 308 heads with template porting and gasket match work (about as far as I would go in this heavy weight) an air gap is perfect. I’ve driven one on a N/A 9:1 360 with a comp 268 magnum and headers on an 8,000 plus pound 4.88 geared W300, and it had reasonably good torque even with the close ratio NP435. Depending on how much boost is being produced, 3.55 to 3.73 gearing may work better by keeping the turbo spooled up under load at its efficiency peak for more time. Water/Methanol (washer fluid) injection and boost timing master is your your friend if going with this plan. I’ve seen it work very well injected into the inlet of a ProCharger, I would imagine it would work pretty well for a turbo, too.

 

[TT5.9mag]

I’ll agree that a street dominator is best for small port heads. They work best with 10:1 plus, a large cam, headers, 700 plus CFM carb, and low gears on a stock headed 318. But if using 308 heads with template porting and gasket match work (about as far as I would go in this heavy weight) an air gap is perfect. I’ve driven one on a N/A 9:1 360 with a comp 268 magnum and headers on an 8,000 plus pound 4.88 geared W300, and it had reasonably good torque even with the close ratio NP435. Depending on how much boost is being produced, 3.55 to 3.73 gearing may work better by keeping the turbo spooled up under load at its efficiency peak for more time. Water/Methanol (washer fluid) injection and boost timing master is your your friend if going with this plan. I’ve seen it work very well injected into the inlet of a ProCharger, I would imagine it would work pretty well for a turbo, too.

It does work well. But Ive only injected it post turbo. Not in the inlet. Ever since the engine masters episode and talking with Brule, I’ve omitted the water and inject straight methanol.