making carb intake into multiport....

[Plato2k5]

Is there any write-ups on doing this conversion? Taking a regualr carb intake manifold and drilling the holes for individual injectors? I know it has been done. I have a mopar 360 la block so there is no stock manifold for multiport injection. I could use one of the latter dodge 360 magnum but the heads would have to be swaped as well.... to much work and my heads have work done to them.

I know MSD sells injector bungs you can epoxy in. Blank fuel rails can be found online...

Does anyone have any information on this?

thanks....

[insanezane]

try this place they sell the bungs and rail stock racepartsolutions.com zane

[zerofloat]

Here is a pic of steel bungs being brazed into a stock cast iron manifold.
http://www.gmcmhphotos.com/photos/showp ... hoto=23797
Most of the project pics are here
http://www.gmcmhphotos.com/photos/showg ... ppuser=311

HTH
Wally Anderson

[Plato2k5]

great info guys, thanks

[Turboperformance]

You know Edelbrock sells a SB intake and fuel rails for the LA V8's (273,318,340,360)?
Super Victor EFI 340/360 #28155*
Fuel Rail Kit for use with #28155 and Bosch style injectors #3641

I made my own EFI intake from a Single Plane Intake using injector bungs I bought off eBay. I made it to use the Magnum injectors as well as the Fuel rails. It was the biggest PITA and if I were to do it again I would buy the Edelbrock set up in a heartbeat. I am just experimenting with a lowly LA 318 to prove to myself if it is worth doing to a 340. I am also using a 90mm TB from a NorthStar. I have not got the set up running yet but I am working towards it a little bit everyday.

Good Luck

[DaytonaTurbo]

Agreed, too much work and too much time considering there is an off-the-shelf efi edelbrock victor intake manifold available for BB and SB mopars.

[fury fan]

I’ve done a handful of bigblock Mopar intakes with 3/8” pipe fittings that are then drilled to size. There’s actually a lot of little-devil-details in converting a manifold but for oddball applications there’s no alternative. For bigblock there is only 1 option – the supertall $300 Victor, which doesn’t suit my needs.

For most factory LA intakes, though, the siamesed-pair runners are not very flat, one is always much steeper than its partner, so that rules out any screw-in fittings because you wouldn’t get complete circles of threads in the steep runner.

However, there are some early 273 (and possibly LA318) intakes with very flat runners that you could drill & tap.

EFI-ready manifolds aren't necessarily that expensive. Depending on what tools you have, you might need to buy a 3/8" pipe tap, some large-size drillbits, pipe fittings, etc. I've spent probably $75-100 on misc items for converting intakes. To do just one intake wouldn't be worthwhile...

[Matt Cramer]

My slant six manifold has sections of aluminum bar stock with the ends cut at a 45 degree angle, welded to the runners. The bar stock was then drilled and tapped for an injector.

[Flo]

I am just searching the right manifold for a 318 too. Have the 302 heads which are going to stay in place, so no MAgnum manifold. The Victor seems way off for my combo. My cam has max torque at 4000rpm and max power at 5500 and is totally done soone after that. I was thinking about convertong an Air Gap and milling off the divider. Anyone of you ahving real experience with that?

[fury fan]

FWIW, Hughes Engines has a nice setup based on an AirGap manifold. It's pricey, but it might give you ideas for your setup.

I have heard of guys removing the plenum divider for port EFI installations. The divider is there to preserve the vacuum signal with a carb, so it is no longer beneficial.

[Flo]

Already ordered one of the Chinese Airgap knock offs for experiments. Will mill off divider (this is really only useful for vacuum signal to carb) and add injectors. Curious to see what happens.

By the way I have a 67 Fury by myself!

[fury fan]

Ah, a 318 Fury in Germany, I think I recognize you from the Drydock? There can’t be too many folks matching that description…

Hopefully we’ll both get EFI working, looks like you’re a step ahead of me with the COP ignition.

You have the Crosswinds intake to try, yes? Let us know how the quality is, I have heard mixed reviews of that manifold.

I have a buddy with a factory 273-318 marine manifold – flat-paired runners and 4-barrel plenum. I think it would be ideal for drilling/tapping for bungs.

[Flo]

HI Fury Fan,
youa re right I am on the dry dock too.
I ordered the "Summit" brand Air gap. Will let you know what I find. I like the dual bolt pattern and the additional meat where I see the bungs in the future. I also have an old Offenhauser, one of the single planes with divider. Also thought about using that one if the Air Gap is too tall.
We will see how much time and money I can afford to sink in there.
Flo

[fury fan]

Dual bolt pattern – you mean it fits LA and Magnum? I searched Summit for a Summit-brand dual-bolt version but didn’t find it. Can you send me a part#?

There might be a Diplomat copcar in my future and EFI would be desirable (either on an LA or a Magnum, don’t know which). I’m planning that build in my mind…

[Flo]

Maybe I am wrong, but I bet a box of beer this is dual pattern from the pics:
SUM-226042
Greets
Flo

[fury fan]

I think you're right, the picture does show both bolt setups. That's a good price for a carby Magnum manifold.

It's too bad they didn't cast a little more aluminum on the runners so it could be drilled for injectors. You'd think manufacturers would get the idea that EFI is the way of the future for some of us guys...

[Flo]

well, they added some meat for NOs-injectors... I gues not enough for fuel injecotrs though. Should make welding easier... Curious about the casting quality!