I was checking out this sweet engine and got to thinking. Could I just buy the intake manifold, which is $400, and bolt it to a salvaged 350 block? What else is unique about the ramjet? The computer? I think doing this would be a heck of a lot more affordable than buying the crate engine, am I wrong? BTW the list price for the crate engine it $4500. I guess that rebuilding a salvaged 350+the intake+computer, HEI, ect might be just as expensive. I dont know jack about rebuilding engines so I need some oppions on this, thanks.

I've been looking at the ram jet too. It is bad. Just hook 12v and fuel, and you're set. But $4500.00 is pricey. The "deluxe" 330 horse engine makes only 20 less HP and 20 less ft lbs of torque.
But its carbutated.:( I think for now I'm going to go with the deluxe. It has the vortec heads that are required for the ram jet(4 bolt intake) so I could upgrade to the injection later. Its also $1500.00 cheaper.:D

Oh yeah, Yes the computer in the ram jet is unique. Its mounted
under the plenum and was originally designed for marine use so its water resistant. Who quoted you $400.00 for the inake and what does that include? That sounds too cheap.

I may be mistaken, but it's my understanding that the Ramjet 350 (crate) requires PREMIUM fuel.

Again, I'm not 100% positive, but I would definitely look into this before I purchased one.

The price is listed at www.gmpartsdirect.com (http://www.gmpartsdirect.com/performance_parts/frameset.cfm) Here is the part # for the intake manifold :12489371.
Yes it dose say that it should run on 92 octane. This is just caus of the compression ratio and you could easily change the ratio.

Does it have a programable chip? If so, then I think you would be able to buy the setup and put it on any 350 you wanted. Just adjust the numbers in the chip. check it!

I dont know about the chip, does anyone? Does the system run closed or open loop? Both?

You may recall the Ram Jet brand from the GM mechanical fuel injection systems of the 50’s. Back then everyone wanted a “fuelie” and today that’s even more true. GM Performance Parts has brought back the Ram Jet name with its all new electronic port fuel injection systems for small-block and big-block crate engines. The small-block Ram Jet 350’s intake manifold is styled like the Ram Jet of yesterday, but that is where the similarity ends. The all new Ram Jet 350 uses state of the art components developed by GM to give you all of the benefits of modern electronic engine management. Who better to fuel inject your hot rod than the people who build 5 million fuel injected cars and trucks per year, including the one in your driveway. Unlike some after market systems, Ram Jet offers great cold starts, hot starts, always ideal air to fuel ratios and exceptional throttle response, power and driveabilty.


The all new 350 horsepower Ram Jet 350 from GM Performance Parts makes it easy to have electronic fuel injection on any 1976 or older vehicle originally equipped with a carburetor. The secret is the industry leading MEFI 3 controller. This new controller fits in the palm of your hand and was originally developed by GM Powertrain for marine applications. MEFI 3 is ideally suited for use in street rods, street machines and sportsman racers. Installation is simple, the Ram Jet 350 is an assembled 350 crate engine with Vortec cylinder heads, Ram Jet induction system, wiring harness, MEFI 3 controller, and detailed instructions. Once installed in the vehicle, a user needs only to supply 12V power and fuel. Please note the fuel pump recommendations in the Ram Jet instruction manual. The Ram Jet 350 has it all, great nostalgic styling, driveabilty unsurpassed by carburetors or after market fuel injection, power to spare and a hot rod idle that sounds like Woodward Avenue in 1969 all over again. GM Performance Parts is “More Than Just Power” and once you’ve driven a Ram Jet you’ll understand why.


Components for this manifold are sold separately, but not as a kit..



Ram Jet 350 Technical Information
Horsepower 350 @ 5200 RPM
Torque 400 @ 3500 RPM
Max. Recommended RPM 5800
Compression Ratio 9.4:1
Block 2 bolt, cast iron
Crankshaft 10243068 cast iron
Connecting Rods 10108688 PM rods
Pistons 12522850 High silicon aluminum withoffset pins
Piston Rings 12522848
Camshaft 14097395 Roller Tappet design
Intake Manifold 12489371
Distributor 1104060
Cylinder Heads 12558060 Vortec
Intake Valves 10241743 1.94"
Exhaust Valves 12550909 1.50"
Valve Springs 10212811
Rocker Arms 12367346 Aluminum roller design
Valve Lash Zero
Spark Plugs MR 43LTS Gap @ .045
Rapidfire #8 @ .035
R42LTS @ .045
Fuel 92 Octane
Ignition Timing 10º BTDC @ 700 RPM

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Copyright © 2000 General Motors Corporation.
Please contact us with any questions or comments.

Originally posted by SweetCJ7
Does it have a programable chip? If so, then I think you would be able to buy the setup and put it on any 350 you wanted. Just adjust the numbers in the chip. check it!

I know that the ram jet crate motor is 9.4:1. So yes you should run premium pump gas. I don't think the chip is programmable but I'm not sure about that. The computer is sealed so I wouldn't think so.

Yes you could run it on any 350, but only with vortec heads.
They have a different bolt pattern thann older heads.

Eddie, When you enter that part number, all it says is manifold.
Is there a description or a picture of what you're getting for that price? Could it be only the manifold minus throttle body, injectors, and computer :confused:

I don't what is inclueded as manifold. You must beable to buy the throttle body, injectors, and computer. If not how would one go about lowering the compression? Swap out the pistons? Is this possable with the RJ350? I would get this thing but I dont want to have to fill it up with premium, gas is expensive enough as is. I won't be starting the project that the engine would go in till next fall so I guess I have some time to figure it out.

They don't sell the ram jet fuel injection as a kit. Only components.
The manifold part# is just the manifold. IMHO If you were to build a 350 short block, buy the vortec heads, then piece together the injection you would be over the cost of the crate motor. But I guess that depends on how much of the short block you allready have and how much you payed for it. I think you would still be best off running premium.

you should be able to squeze by with 89 with out any problems. i dont know what tthe factory comp on my 92 351w is but i thought it was 92.5 to 1. i have a 6 psi supercharger and get by on 89 for around town. i do put in 92 if i am towing or going to the dunes (gets close to 7 psi at 6500 and some times i'm a little slow shifting:D)

Originally posted by it'll fit
you should be able to squeze by with 89 with out any problems. i dont know what tthe factory comp on my 92 351w is but i thought it was 92.5 to 1. i have a 6 psi supercharger and get by on 89 for around town. i do put in 92 if i am towing or going to the dunes (gets close to 7 psi at 6500 and some times i'm a little slow shifting:D)

I agree it wil be fine day to day with cheao stuff, but if you plan on getting on it or putting any kind of load on it fill it with premium. hell I know a guy who got away with 89 in his 11 sec. Nova when he was just driving to and from work.

WHat if I ran the cheep stuff and just dumped in some octane boost when I went wheeling? Or if I filled it with half 89 and half 92 would that make it 90.5 octane? I won't be driving the jeep with this engine in it till the spring of '03 maybe by then opec will be run by america and gas will be $.50/gal
:D HECK YEAH :D

Last time I called you could get all the separate parts EXCEPT the injection unit so you had to buy it complete.

Originally posted by Aggro
Last time I called you could get all the separate parts EXCEPT the injection unit so you had to buy it complete.

You might be right. :( Let's all e-mail GM so they release a ram-jet injection kit. I want one. Just cant afford it now.

So do you get a ramjet membership card so that you can buy a replacement part if you break one. I dont know if I like the idea of having somthing go out (I knw not likely but anything is possable) and not being able to pick up a new part easily. If theay do have somesort of ramjet owners thing then one of us just has to buy the whole thing then get the injection chit for everyone else to hepl defray the cost of the engine a bit :D

You can get a kit from Arizona Speed and Marine.

http://www.azspeed.com

You can get the ramjet front TPI/LT-1 style air cleaner/throttle body, or you can get the superjet sytem that looks almost just like the 50s fulie system where the throttlebody is on the drivers side.

You have to use vortec heads, though there are alum units out now I think. Plus the wortec heads work really well also.

I hope this helps

later:jeep:

Mieser, thats a cool site. I dont thing I would spend $3-4,000+ just for a injection kit when I can get the crate engine for $4500. cool stuff though.

Top. Anyone have anything new to say about the RJ 350?

Originally posted by Eddie Mcstiff
Top. Anyone have anything new to say about the RJ 350?

ahh yeah I want one:D

oh yeah the high octane thing,people use a thinner than stock head gasket to raise compression ratio ,so maybe you could use a thicker one to lower it.

for a grand more you could get a LS1 all aluminum crate motor:D. this motor is light(lighter than most v6s), simple upgrages and your over 425hp, but definatly 92 octane @ 10.25 to 1. This is starting to be the new buggy(sand) motor of choice because of the weight and turn key power.

Jeremy's Roggy-Built Cruiser has one. Those motors are sweet!

just fired one up last night in a friends girlfriends truck . 72 longbed 37ssrs,60 456 (nice) We never messed with the wires but had to move #1 two positions counter clockwise and then the timing was a little too far advanced(pinged) but seems to fine now and it does run strong for a heavy truck. One say i will say in order to get everything nice under hood there is a lot of little things to think about like fuel lines, aircleaner, routing of harness in a 72 4x4 was kind tight cause the distributer is on the firewall real tight unless you move motor forward.
And the other thing was dont forget you have to have vortec heads for this intake!

Originally posted by Eddie Mcstiff
Top. Anyone have anything new to say about the RJ 350?

Two things.........it comes from the factory as an open loop motor - I would go with the www.azspeed-marine.com closed loop setup for it, so you are then using an O2 sensor to make the mileage and the air/fuel mix more precise.

Second thing - if you are indeed in Boulder at elevation, you probably won't have as much of a pinging problem if you attempt to run 'non-premium' fuel. Not sure what you pay for fuel now, but in Oregon the diff is about $.18 per gallon. Worth it, I run it in my TPI406 but it is NOT a daily driver. Changing head gaskets at first would probably void the warranty, and losing power is never a good thing..................:)

Blazzin, I am located in Boulder most of the year and do most of my wheeling over 5500ft. So do you think the closed loop kit replace the computer or does it hook to it? The site wasnt very clear. If it replaces it then I could prob just get a short block and the closed loop system and make my own RJ350.