single plain efi intake manifold
Burning Brakes
Joined: Jul 2006
Posts: 1,080
Likes: 2
From: Pittsburgh PA
where? all the links here in this thread are already converted manifolds. I"m talking about using other single planes that are not yet converted and have them done up, drilled for bosses and custom rails.
There are other single planes out there that work better than victor and the holley.
AS far as the elbows facing forward you can twist the flange around and mount it sideways like a mustang. Anesthes has done this just fine on his vette
There are other single planes out there that work better than victor and the holley.
AS far as the elbows facing forward you can twist the flange around and mount it sideways like a mustang. Anesthes has done this just fine on his vette
Last edited by Orr89rocz; Oct 31, 2008 at 07:39 PM.
Burning Brakes
Joined: Jul 2006
Posts: 1,080
Likes: 2
From: Pittsburgh PA
I hope he gets in here to answer more questions
The stock height of the 9901-101-1 Holley manifold is 5.65". We milled it down to 4.125".
The elbow will be 4.75" on the hood centerline. This will fit under the stock C4 hood.
The elbow will be 4.75" on the hood centerline. This will fit under the stock C4 hood.
Drifting
Joined: Feb 2003
Posts: 1,978
Likes: 2
From: San Antonio Texas
Orr89rocz...I mentioned one place above, and I'm thinking Anesthes had his made there too... I could be wrong. A sideways "Elbow would allow a fabricated plate/secondary runner; to equalize the Plenum length difference with an RPM. The MAF and Air filter setup could be a real PITA though.
Here's a thought that recently occured to me...how about a 1/2" thick 4-Hole spacer as the Elbows' base. These Single-Plane Intakes are originally designed to be sucking from 4 throttle bores...The 1/2" holes might help direct the flow into the runners, and might "effectively" lengthen the Runner, picking up the bottom-mid range. Something to ponder...
Here's a thought that recently occured to me...how about a 1/2" thick 4-Hole spacer as the Elbows' base. These Single-Plane Intakes are originally designed to be sucking from 4 throttle bores...The 1/2" holes might help direct the flow into the runners, and might "effectively" lengthen the Runner, picking up the bottom-mid range. Something to ponder...
Burning Brakes
Joined: Jul 2006
Posts: 1,080
Likes: 2
From: Pittsburgh PA
As far as i know, that holley manifold was bought already made up for EFI and he had it milled down to clear the hood and had the intake elbow made at intakeelbows.com
I think these intakes should have no problem sucking in the air no matter how far the TB is away from the top of the 'plenum' of the base manifold. I have a camaro and may be getting a small cowl hood so i have much more room to play with than C4's. I may convert this winter to see if i can gain anything over the HSR. If not then atleast the carb manifold will be easier to do direct port nitrous with
also keep in mind these single planes are designed to be wet flow manifolds and converting to efi changes it to dry flow... so how that will effect air flow/distribution thru the manifold i have no idea... but i'd assume you will have great low end with fuel injection as compared to carb cars
Carbs rely on velocity to atomize the fuel dumped in by the carb at a low pressure. with our injectors we got high pressure and a nice spray pattern so getting the fuel to distribute and atomize is no problem.
This i why i believe minirams with tiny 3" runners can make flat torque curves and have a healthy bottom end. Carb intakes need abit longer runners to gain velocity to get that fuel distributed right
I think these intakes should have no problem sucking in the air no matter how far the TB is away from the top of the 'plenum' of the base manifold. I have a camaro and may be getting a small cowl hood so i have much more room to play with than C4's. I may convert this winter to see if i can gain anything over the HSR. If not then atleast the carb manifold will be easier to do direct port nitrous with
also keep in mind these single planes are designed to be wet flow manifolds and converting to efi changes it to dry flow... so how that will effect air flow/distribution thru the manifold i have no idea... but i'd assume you will have great low end with fuel injection as compared to carb cars
Carbs rely on velocity to atomize the fuel dumped in by the carb at a low pressure. with our injectors we got high pressure and a nice spray pattern so getting the fuel to distribute and atomize is no problem.
This i why i believe minirams with tiny 3" runners can make flat torque curves and have a healthy bottom end. Carb intakes need abit longer runners to gain velocity to get that fuel distributed right
Le Mans Master
Joined: Jan 2002
Posts: 9,036
Likes: 13
From: Edmonton AB
like the LT conversions.
I still can't come up with a readily workable method of using an
Edelbrock RPM Manifold without a raised hood.
Like the 7501 Performer RPM Air-Gap Dual Plane?
Why not modify or remove the #7501 coolant crossover to create
more clearance?
While the intake is being modified to have the injector bungs and
fuel rail mounting tabs added, perhaps the crossover could be
removed an inch or so up from either side of the intake flange. This
would leave passage stubs that a skillful fabricator could weld
-12 AN male fittings into with relatively little risk of causing intake
flange warpage. Then with some hose ends, some hose and one of
Weiand's #7134 Remote Thermostat Housing, coolant flow to the
radiator could be re-established.
A similar approach might work on other intakes with raised or integral
crossover passages.
Courtesy of Jeg's - Weiand 7134
Or maybe look closely at the crossover on AKS Racing's intake.
.
Drifting
Joined: Feb 2003
Posts: 1,978
Likes: 2
From: San Antonio Texas
...someone mentioned above about useing a Dual-Plane Intake like an RPM. Something I've been thinking on for a while; a "pet project". The place I mentioned above will weld in Bungs and a Fuel-Rail setup on an RPM. From all I've ever been able to gather, the problem is with the un-even Plenum configurations/volume of the Dual-Plane. Try to come up with a way to effectively equalize the Plenums; within a larger Plenum, and keep it all under the 8 to 8 1/2" Hood space we have ( RPM 4.20" front-5.25" rear). From 0-6500 RPM it should be killer. I've heard of 600 HP RPM manifold cars; it should be able to support more with Dry-Flow.
As was mentioned...about the Low-speed loss with Single-Planes... I know there is with a Carb; I don't know with FI. Some Ads claim there is no loss... What I mentioned was a possible improvement if there was. I was thinking a 4-Hole Spacer, 1/2" thick, with about a 1" deep Divider running from Left to Right across the middle of the bottom of the Spacer. This might "effectively" lenghten the Runner length by an 1" or 2". Then build a Plenum on that base. I'm thinking that where the Runner opens to the Plemun determines it's length. Pipe tuning applies to wet or dry flow; it might pick up the bottom-mid range. Just some things to think about...
As was mentioned...about the Low-speed loss with Single-Planes... I know there is with a Carb; I don't know with FI. Some Ads claim there is no loss... What I mentioned was a possible improvement if there was. I was thinking a 4-Hole Spacer, 1/2" thick, with about a 1" deep Divider running from Left to Right across the middle of the bottom of the Spacer. This might "effectively" lenghten the Runner length by an 1" or 2". Then build a Plenum on that base. I'm thinking that where the Runner opens to the Plemun determines it's length. Pipe tuning applies to wet or dry flow; it might pick up the bottom-mid range. Just some things to think about...
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Melting Slicks
Joined: Oct 2000
Posts: 3,426
Likes: 4
From: Heidelberg PA
Cruise-In V Veteran
...someone mentioned above about useing a Dual-Plane Intake like an RPM. Something I've been thinking on for a while; a "pet project". The place I mentioned above will weld in Bungs and a Fuel-Rail setup on an RPM. From all I've ever been able to gather, the problem is with the un-even Plenum configurations/volume of the Dual-Plane. Try to come up with a way to effectively equalize the Plenums; within a larger Plenum, and keep it all under the 8 to 8 1/2" Hood space we have ( RPM 4.20" front-5.25" rear). From 0-6500 RPM it should be killer. I've heard of 600 HP RPM manifold cars; it should be able to support more with Dry-Flow.
As was mentioned...about the Low-speed loss with Single-Planes... I know there is with a Carb; I don't know with FI. Some Ads claim there is no loss... What I mentioned was a possible improvement if there was. I was thinking a 4-Hole Spacer, 1/2" thick, with about a 1" deep Divider running from Left to Right across the middle of the bottom of the Spacer. This might "effectively" lenghten the Runner length by an 1" or 2". Then build a Plenum on that base. I'm thinking that where the Runner opens to the Plemun determines it's length. Pipe tuning applies to wet or dry flow; it might pick up the bottom-mid range. Just some things to think about...
As was mentioned...about the Low-speed loss with Single-Planes... I know there is with a Carb; I don't know with FI. Some Ads claim there is no loss... What I mentioned was a possible improvement if there was. I was thinking a 4-Hole Spacer, 1/2" thick, with about a 1" deep Divider running from Left to Right across the middle of the bottom of the Spacer. This might "effectively" lenghten the Runner length by an 1" or 2". Then build a Plenum on that base. I'm thinking that where the Runner opens to the Plemun determines it's length. Pipe tuning applies to wet or dry flow; it might pick up the bottom-mid range. Just some things to think about...
To my suprise I got my best 60' 1.49 with the single plane. It hits harder than the Superram and it idles better.
Drifting
Joined: Feb 2003
Posts: 1,978
Likes: 2
From: San Antonio Texas
That's cool, I know your car runs good. Your manifold is the Super-Victor isn't it? I do like the Plenum Jeb made for you. I was thinking... he could have angled the sides out at the top for, more Plenum volume. Might be a little improvement ???
I forgot to mention; about a Spacer like I posted above... that the lower RPM air-flow velocity should also increase, by drawing through the Throttle Body holes/ Divider. Both as a result of a longer "length", and the Dual-Plane like configuration of it. It's all speculation on my part; might work... sounds reasonable to me
The depth of the Divider might be criticle; too deep and it might block some runners ability to make the upward turn. Too shallow and it might not have the desired influence on the flow. How would the runners react; with the Manifolds' Plenum still being open on the bottom, between both "sides" ???
I forgot to mention; about a Spacer like I posted above... that the lower RPM air-flow velocity should also increase, by drawing through the Throttle Body holes/ Divider. Both as a result of a longer "length", and the Dual-Plane like configuration of it. It's all speculation on my part; might work... sounds reasonable to me
The depth of the Divider might be criticle; too deep and it might block some runners ability to make the upward turn. Too shallow and it might not have the desired influence on the flow. How would the runners react; with the Manifolds' Plenum still being open on the bottom, between both "sides" ???
Melting Slicks
Joined: Oct 2000
Posts: 3,426
Likes: 4
From: Heidelberg PA
Cruise-In V Veteran
That's cool, I know your car runs good. Your manifold is the Super-Victor isn't it? I do like the Plenum Jeb made for you. I was thinking... he could have angled the sides out at the top for, more Plenum volume. Might be a little improvement ???
I forgot to mention; about a Spacer like I posted above... that the lower RPM air-flow velocity should also increase, by drawing through the Throttle Body holes/ Divider. Both as a result of a longer "length", and the Dual-Plane like configuration of it. It's all speculation on my part; might work... sounds reasonable to me The depth of the Divider might be criticle; too deep and it might block some runners ability to make the upward turn. Too shallow and it might not have the desired influence on the flow. How would the runners react; with the Manifolds' Plenum still being open on the bottom, between both "sides" ???
I forgot to mention; about a Spacer like I posted above... that the lower RPM air-flow velocity should also increase, by drawing through the Throttle Body holes/ Divider. Both as a result of a longer "length", and the Dual-Plane like configuration of it. It's all speculation on my part; might work... sounds reasonable to me
The depth of the Divider might be criticle; too deep and it might block some runners ability to make the upward turn. Too shallow and it might not have the desired influence on the flow. How would the runners react; with the Manifolds' Plenum still being open on the bottom, between both "sides" ???
Le Mans Master
Joined: Jan 2002
Posts: 9,036
Likes: 13
From: Edmonton AB
Here is what a converted 7501 would look like. Further work would
need to be done to the coolant crossover.
And here is what a 7516 (the Vortec version of the 7501 Performer
RPM Air-Gap Dual Plane) would look like.
Part of the image is obscured as a courtesy to the fabricator.
.
Drifting
Joined: Feb 2003
Posts: 1,978
Likes: 2
From: San Antonio Texas
Nice Pics... how well do they work? I'm guessing the second pic Manifold had it's Divider removed ? Trying to "even up" the sides...I personally don't know for sure if it's a problem, but everytime I've posted about a Dual-Plane, I'm told the sides don't flow the same.
Le Mans Master
Joined: Jan 2002
Posts: 9,036
Likes: 13
From: Edmonton AB
The slot in a plenum divider is a tuning technique for carbureted
operation. Like the 7501 above, the OEM slot in the divider of the
7516 had been filled. The divider is continued up into a fabricated
plenum that bolts to the intake.
Longer runners lower the RPM at which the torque peak occurs,
relative to shorter runners.
My vote is that choosing a dual plane design, then proceeding to
cut away the divider would be less satisfactory than choosing a
single plane.
Originally Posted by Curveit
... everytime I've posted about a Dual-Plane, I'm told the sides
don't flow the same.
don't flow the same.
side-to-side issue.
Before conversion and remedial work, an OEM 7501 flowed
as follows:
CFM @ 28" H²O
1) 271 -- 2) 262
3) 281 -- 4) 257
5) 288 -- 6) 264
7) 259 -- 8) 264
The numbers in black represent the ports fed by the deeper3) 281 -- 4) 257
5) 288 -- 6) 264
7) 259 -- 8) 264
plenum section on the left/drivers side. Those in red represent
the ports fed by the shallow plenum section on the right/pass side.
.
Drifting
Joined: Feb 2003
Posts: 1,978
Likes: 2
From: San Antonio Texas
Yea, back in the '60s we all would cut the Dividers for more top-end power (cheap mod). I'm also well aware of In & Ex tuning lengths; like the PipeMax program. I you were running a Carb, the Drivers side (Deep) would "draw" harder, and run a little richer, with equal Jetting. Carbs can compromise some; that's how Dual-Planes can work. If you wanted one "spot on", you'd really need to stagger the Jetting.
To equalize the thing for FI; if it really is a problem... the easiest solution would be to fabricate a ring around the edge of the Shallow opening, the same height as the other side is deep. The problem then, is the airflow from the ThrottleBody smashing into it, and/or the lack of height between the new opening and the Plenum roof. I also thought of 2 "elbows"; one longer, by the difference between the sides; opening into a larger Plenum. Do you know how either of the Manifolds pictured worked out?
To equalize the thing for FI; if it really is a problem... the easiest solution would be to fabricate a ring around the edge of the Shallow opening, the same height as the other side is deep. The problem then, is the airflow from the ThrottleBody smashing into it, and/or the lack of height between the new opening and the Plenum roof. I also thought of 2 "elbows"; one longer, by the difference between the sides; opening into a larger Plenum. Do you know how either of the Manifolds pictured worked out?
