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Interest in an EFI L-series manifold?

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I'm looking into making a 4-cylinder manifold for the L motors. How much interest is there for these? These are fabricated from raw aluminum, not cut up L28 manifolds.

 

I'd be selling them complete with fuel rail, regulator, and throttle body, but the prices aren't even thought about yet...I'd need to see how much interest there is in them.

 

I have photos of the L6 manifold that will be going on my car shortly if you want to see what kind of manifolds I'm talking about.

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Im gonna be building an L4 turbo mani that would go good with this lol

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This is the partial manifold, not including the plenum or most of the accessories...

 

IMAG0460_zps23e5864f.jpg

 

Getting the fuel rail in place:

 

IMAG0480_zps4e002a94.jpg

 

Regulator and fuel lines fitted up:

 

IMAG0489_zps4446bebf.jpg

 

And with the plenum installed...this is actually a manifold designed to hold boost!

 

IMAG0491_zpsfc0f1d3b.jpg

 

The dual-plenum design would cost more, there is more math involved and it's harder to package.

 

IMAG0492_zpsb22871ca.jpg

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The manifold you see in the photos above probably has 300hrs of labor involved, between the design and fabrication. I can seriously cut that down; but the parts bill is about the same...

 

The manifold I will be offering will be a single throttle system unless someone just waves cash in my face. The ITB stuff is a BITCH to get working right.

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interested, L4 one would need to be shorter to clear brake booster and such. all depends on price.

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Price-wise, we're looking at about 150$ in materials for the manifold and fuel rail only, about 12 hours labour, plus the throttle body and regulator if you guys don't want to source your own.  The fuel rail wouldn't come with the integrated regulator housing unless you were buying the regulator too. Easier on me to source them than try to tell you where to get one.

 

150$ for materials, 240$ in labour, Throttle body is to be determined and the regulator is 40+50$ housing, you can buy the standalone housings online for about 80$ each, without the regulator...Or I can sell a standalone regulator+housing if you don't need a manifold but want a modern regulator, too.

 

What size throttle body do you all want?

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Just to be clear...this is a semi-custom part. I will need specific information and will tune the manifold based on your displacement, cam, turbo/nonturbo, and the vehicle...so a worked over, ported-head L20B manifold won't be the same as a bone-stock L16 manifold.

 

The price will vary a little based on options, and if you want me to source fuel injectors I can do that too. If you need a wiring harness, I can make that to match the manifolds, all of this stuff is available if you've got the interest.

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As far as clearing the engine bay, I will need measurements from a few different cars and trucks to pattern these with...That manifold in the photos has intake runners of 15.5" length, tuned for 3rd wave resonance at 5300RPM. The runner inside diameter is tuned based on displacement and desired torque peak, in conjuction with cam duration and lift.

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yeah the L4 engine bays will have complications with something of similar length.

esp the 620s with the larger brake booster.

skib whats u gots going???!~

Iv got a flange laying around Ill eventually build into an L4 turbo mani.

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So how much room from the head, do you guys have? measuring from the flange surface straight out until you hit something, Above cylinder #4 exhaust, and cylinder #1 exhaust?

 

If someone has a photo of a 510 engine bay, looking down on the L, and can overlay those measurements and the clearance to the shock tower that'd be very helpful.

 

Are these going on stock, unported heads or ported heads? What is the intake port diameter? I only have a 210 casting to work with, with the 1.125" intake ports.

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There is so much involved here, I would be very interested in this, and I would like as complete a package as possible.

I have a W53 closed chamber head with 280Z valves, the intake ports are 1 1/2 inches.

My block is a Z22 punched out to except stock Z24 pistons with the stock L20b/Z22 crank, so it is basically a 2300cc engine.

I just went out and looked at what I have for room in a stock 521 situation, stock master brake cylinder(MBC), I have measuring from the mount surface of the #4 exhaust hole on the head to the MBC 13 inches, same with the #4 intake hole, the back edge is 13 inches, this does not accommodate for future plans for a power brake booster.

The fact is that the shorter the better, there just is no way to custom make each one at a reasonable price.

I was actually looking at this, but I don't know enough to make an informed decision.

http://www.extrudabody.com/servlet/the-135/Twin-SU-SU's-MGB/Detail

Datsun%20twin%20SU_1388c.jpg

I cannot seem to make the link work.

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That manifold has 15.5" runners...but is only 14 inches from the cylinder head to the outside curve of the plenum. We can get good runner length out of  a 13" limit.

 

a 1.5" port would mean a torque peak of about 4400RPM, but the manifold would have to be 15 inches from cylinder head to the end of the runner to match that...would make for the highest peak torque. We can shoot for lower peak numbers and wider powerband, by making the runner length about 14" long, we can make highest power between 4400 and 6000RPM. This would give us a total manifold length of  10" to the end of the runner, or about 12" overall to the outside of the plenum, because we need to account for the length of the intake port inside the head.

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That extrudabody kit is only for the two throttle bodies...it doesn't include the SU manifold...

 

I'm considering the sale of a complete manifold with fuel rail, and can make it a package ready to be wired up to your ECU.

 

Take note...I'm able to provide a manifold harness, but you're on your own for the ECU. I can provide the harness with the wires labeled for you to connect to your ECU, but that's about as far as I can go for reasonable money. I can do full megasquirt harnesses, but without having the car in my hands, it's pretty difficult to accurately price something like that.

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That manifold has 15.5" runners...but is only 14 inches from the cylinder head to the outside curve of the plenum. We can get good runner length out of  a 13" limit.

 

a 1.5" port would mean a torque peak of about 4400RPM, but the manifold would have to be 15 inches from cylinder head to the end of the runner to match that...would make for the highest peak torque. We can shoot for lower peak numbers and wider powerband, by making the runner length about 14" long, we can make highest power between 4400 and 6000RPM. This would give us a total manifold length of  10" to the end of the runner, or about 12" overall to the outside of the plenum, because we need to account for the length of the intake port inside the head.

 

Basically I don't understand this, even though I do understand your measurements.

Here are some photos of my dirty engine compartment, it is 11 1/2 to 12 inches from the face of the head to the outside of the air filter housing.

DSCN1024.JPG

 

DSCN1025.JPG

 

DSCN1026.JPG

Fact is, I have no use for an EFI thats power band is where you are talking about, I rarely run it up past 4500rpms, so if this EFI is basically for racing, I have no real use for it, I am looking for a general use EFI that would get decent mileage, and that would generally act like my LZ23, or possibly more power all the way around in the 2500 to 4500rpms.

I hope these photos help you in some way, I have a lot of crap stuffed in my engine compartment, but I have seen a lot more crammed in there on other peoples builds.  :lol:

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Looking at your photos, 12" to the outside of the plenum (which is smaller top-to-bottom than that air cleaner housing) would allow an intake runner length of 14", which should be plenty to give you a fat torque curve.

 

The manifold would be built to maximize power for the simple fact that Horsepower=Torque*RPM/5252. If you're not going to match components (I.E if you guys are happy with a compromised design just to get an easy-to-obtain EFI manifold) Then a simple, effective design can be built and I can make a few at a time, so wait time and fitment would go down.

 

How many people would be bolting this to an engine that they are going to drive like a stocker? (limited rev range, power is a secondary consideration) If this is the target application, then I could probably do one in 8 or 10 hours instead of 12, the price would come down a little.

 

For good mileage, ditch the ported head, run a tiny cam, and about a 32mm intake runner, with a 45mm throttle.

 

As far as being able to produce these at a "reasonable price", the part of the fabrication that takes the longest is jigging and welding in the injector bungs. That's four to five hours of work, because an O-ring injector WILL NOT seal if the ports are not aligned to within 0.020". It'll blow fuel all over the manifold and engine bay if it's not, and that will generally cause bad mileage and other nasty things (fuel smell, gunked up dirty parts, engine fires...)

 

What does it cost to import an L20B EFI manifold and cylinder head to the US? (The EFI head has a different bolt pattern for the intake manifold, so it's either drill your head for the new bolt pattern or get the H77 head casting too.)

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Tons of people would be interested, but interest correlates inversely with price. So interest in the manifold will be dictated by how much it's going to cost me. I can't say how interested I am without knowing what the final price is.

 

What about the air filter?

 

Right now your price ads up to be about $430, plus whatever else anyone might need. Once people get injectors and everythign else, it's going to be way up there. I think the realistic interest will be rather small. I'd like to see it done, because I love efi on an L series, and even made my own setup once. But it's unlikely I'd be interested at $400+

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Fair enough. I'm not going to do it for charity, and the photos I posted are of a manifold that I am rather unwilling to duplicate...My intentions were to build a manifold for the 4-cylinders that has the plenum attached, nonremovable, and a throttle body in the front, similar to most other EFI manifolds.

 

Any slip-on air filter would have worked fine for that. No worries, guys. If anyone does want one, they can send a message.

 

430$ for a complete manifold, with a fuel rail to match, ready to have injectors you sized installed and a throttle body you choose installed, doesn't seem too bad to me. Look at the price for an aftermarket manifold for the CA18, RB26, 2JZ, etc...quite a lot cheaper!

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Looking at your photos, 12" to the outside of the plenum (which is smaller top-to-bottom than that air cleaner housing) would allow an intake runner length of 14", which should be plenty to give you a fat torque curve.

 

The manifold would be built to maximize power for the simple fact that Horsepower=Torque*RPM/5252. If you're not going to match components (I.E if you guys are happy with a compromised design just to get an easy-to-obtain EFI manifold) Then a simple, effective design can be built and I can make a few at a time, so wait time and fitment would go down.

 

How many people would be bolting this to an engine that they are going to drive like a stocker? (limited rev range, power is a secondary consideration) If this is the target application, then I could probably do one in 8 or 10 hours instead of 12, the price would come down a little.

 

For good mileage, ditch the ported head, run a tiny cam, and about a 32mm intake runner, with a 45mm throttle.

 

As far as being able to produce these at a "reasonable price", the part of the fabrication that takes the longest is jigging and welding in the injector bungs. That's four to five hours of work, because an O-ring injector WILL NOT seal if the ports are not aligned to within 0.020". It'll blow fuel all over the manifold and engine bay if it's not, and that will generally cause bad mileage and other nasty things (fuel smell, gunked up dirty parts, engine fires...)

 

What does it cost to import an L20B EFI manifold and cylinder head to the US? (The EFI head has a different bolt pattern for the intake manifold, so it's either drill your head for the new bolt pattern or get the H77 head casting too.)

 

Its just that it would be really hard to tuck those long runners in a 510 engine bay.

Something more balanced would be best, see the cannon sidedraft manifolds. Something with similar fitment would be ideal.

 

U67 stock porting is 35mm, and a lot of people street port around 38mm.  

A lot of us aren't interested in a race car manifold, or some ridiculously restricted fuel economy manifold.  The best option here would be finding a balance of what people are looking for.

 

If I where not going sidedraft carbs, under $500 for an EFI manifold is a great price.

 

Fair enough. I'm not going to do it for charity, and the photos I posted are of a manifold that I am rather unwilling to duplicate...My intentions were to build a manifold for the 4-cylinders that has the plenum attached, nonremovable, and a throttle body in the front, similar to most other EFI manifolds.

 

Any slip-on air filter would have worked fine for that. No worries, guys. If anyone does want one, they can send a message.

 

430$ for a complete manifold, with a fuel rail to match, ready to have injectors you sized installed and a throttle body you choose installed, doesn't seem too bad to me. Look at the price for an aftermarket manifold for the CA18, RB26, 2JZ, etc...quite a lot cheaper!

I think the problem is your posting this at RATSUN, a lot of the members here are use to building things on the cheap!

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