shafrs3

Folks,
Here is a shot of my first attempt at a performance EFI intake solution that will fit under the stock BB hood. The plan is to use either a GM TPI throttle body or two single 65mm throttle bodies, and add a crossover pipe to make the two plenum's common. Lower half is a 502 ramjet.

Comments and suggestions always welcomed.

BBShark

Cool. Nice work.

Do you have the fuel rail for the Ramjet? If you do I would like to know what you did with the end of rail purge valve. Mine points up right in the front. Looks like I will have to bend it down. I really wish the fuel and return lines came off the passenger side. What are you getting for hood clearance at the front of the manifold? I think I have 8" from block to underside/center of hood.

Two 65mm throttle bodies sound like they may be too big for a street car. I know people who have swapped their TPI 48's with 58's and not been happy with tip in throttle response.

jburnett

Not bad...How low do you need it to be? I build a lot of sheet metal intakes and EFI single plane conversions (mainly for the C4 guys) that stay under the stock hood.
-Jeb

MEGALADON

Do you have any photos of what you can do for a LT1 intake.
more plenum would be nice, and I don't need stock height!!.
I am doing a 95 LT1 swap in my 81.

Shafrs3, that is a cool intake build, hats off to u. If it works
will you build me one also?? PM me if you have to.

jburnett

Sheet metal LT1...
-Jeb

MEGALADON

THATS AWESOME

shafrs3

BBShark,
I'm going to cut that bent section off and replace it with a custom bent piece. I got the fuel rail from an EFI truck application, which I believe is the same thing. The fuel connections are on the drivers side, not much room on the pass side because of the distributor. My existing setup is measuring 8.25" up from the forward lifter valley rail, leaving about 1/2 of clearance to the front of the hood. This setup is 1/4" below that.

The guys with the 58mm throttle bodies, what kind of tip-in problems are they experiencing and are they small blocks? Mine is 496ci and the existing throttle body (4V Holley) flows 900 cfm, all 4 barrels operate as one, no tip in problems.

shafrs3

If IS the operative word here. This is also my first attempt at aluminum welding, I'm using a consumer grade MIG gun and it is not the ideal setup, but it sticks.

Simmo

Have you done any low profile BBC intakes? I love your work.

jburnett

It's been awhile but I built one for a BBC/C4 Vette conversion about two years ago. I'll have to dig up the 3.5" floppy that the pics are on; I used to have a Sony Mavica digital camera and used to put them on the 3.5's... Problem is I have a stack about 4' tall of discs, only part of them are actually named! If I can find the disc I'll post some pics. Full sheet metal like the above LT1 manifold... Entire manifold height if I recall completely was 7.250" from the front china rail on the block... It cleared a stock C4 hood by .250".

Shafrs3- I think you're doing a very admirable job working with a MIG on aluminum. I'd rather get my d!ck caught in a bear trap than MIG aluminum!!!!
-Jeb

shafrs3

65mm throttle bodies attached, hopefully they're not too big.

shafrs3

Thanks Jeb, it's been a bit of a steep ramp-up on the 'ole learning curve.

bb69

That's great. I have been planning in making a manifold for my BB, but I never considered doing it that way. That seems to eliminate the really hard parts: ie locating the distributor and making sure the flanges are flat. Can you please take some close up shots of the injector bosses?

I have a throttle body from a Ford GT I am planning on using. I was thinking of making two separate plenums and joing them just behind the throttle body as Dodge does with the Viper intake. Anyway, great job, and please post more pics and results when you get it all installed and running.

Ken

PS. What computer are you running?

shafrs3

Ken,
Thanks for the complements. Your right, using the lower half of the Ram Jet manifold saves a ton of work. Originally I wanted something similar to a Weber down draft configuration, but decided that keeping throttle plates synchronized would be a pain. This is a work in progress, I still need to decide where to locate the IAC. My ECU is from Holley.

bb69

I have a Megasquirt system, and am in the middle of getting it setup on the car. Right now, I am just using a throttle body with 4 injectors placed below the throttle blades.

From the last pic, it looks like the injector bosses are positioned towards the center of the manifold? That should make the plumbing of the fuel rails and lines a little harder, but also cleaner. Please keep posting pics.

Ken

shafrs3

The bosses are in fact tilted inward. I like this configuration, it makes for a tidy package. All the wiring, injectors and fuel plumbing will reside inside the lifter valley under the plenum. I'm using the fuel log from the GM 8.1 liter truck EFI application which I believe is the same P/N used in the Ram Jet so fuel plumbing is nearly plug-in-play.

dsagers

If you want a big TB for a low price, look for an early 90s TB from an Infinity Q45 with the 4.5L engine. Usually $100 on ebay, much less $$ than some of the custom and after market TB.

shafrs3

Modified factory fuel rail to locate pressure gage fitting to the side and installed injectors. Lots of room under that fuel log for other fun stuff.

BBShark

Looks like you made a new thermostat housing. Is that what I'm seeing?

shafrs3

Didn't make it, it's a Moroso unit that's been trimed down and a plate welded to the top to eliminate one gasket.