Technical Rochester Ramjet Fuel Injection

I'd love to put a 64-65 unit on my 64, but they've never been in my price range during my lifetime. I've been drooling on them since I was 16 in 1990. Seems like last week.

Devin

 

F.I.57ChevyNut would be a good guy to ask. Maybe he’ll chime in. He raced them in jr stock as well as in his daily driver.


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I ran a '59 unit on my '57 back in the '60s and after learning how to tune it made good power on the 301.
I'll try and give a brief description of how it works. There is basically a float bowl on the side with a high pressure pump in the bottom submerged in gas that is driven by a short "speedometer" cable from the distributor. The discharge from the pump goes to a spool valve that opens and closes a port to allow the gas to go to a little eight sided fitting on the bottom of the plenum and from the fitting there are small copper lines that go to each injector at the top of the intake port. There is a vacuum diaphragm with a mechanical link connected to the spool valve. One side of the diaphragm gets it's signal from a line connected to the plenum and the other side of the diaphragm is open to atmospheric pressure. The engine vacuum created in the plenum raises and lowers the diaphragm and the link attached moves the spool valve to allow gas to go to the injector nozzles. When you put the pedal to the floor the engine vacuum goes low and the spool valve opens to go full rich to the injectors. At idle the vacuum is high and the valve is almost closed for a lean mixture.
For a rich mix for starting there is a micro switch on the throttle linkage and when you push the pedal down it clicks the switch and a solenoid fully opens the spool valve for a rich mix.
The system works well unless you have a vacuum leak or a radical camshaft. My biggest problem running on the street was that vacuum windshield wipers on the '57. When it rained and you turned on the wipers the engine would go full rich. It wouldn't be a problem with the wiper systems available today but in 1964 it was.

 

Injection unit is long gone but I still have the dual cable distributor (tach, injection) that maybe some Corvette nut will give an insane price for.

 

The 315 hp 60 and 61 did not have fins the 275 hp hydraulic lifter motors did . Getting rid of the fins let them raise the inside about 1/2 inch for more air flow. Fuely systems had to many screws to adjust and people could not leave them alone kind of like a theroquad.

 

sunbeam - These FIs had only 3 screws to adjust......air meter, fuel mixture, and idle speed......quite simple. Most guys who could not figure them out had too many loose screws!

 

That must be why so many were taken off.

 

Inside the 8 injectors is a micro "orifice" that has to be installed a certain direction, at least on my '62 FI.
Back in the mid '70's I traded 2 new Mickey Thomson slicks for a complete '62 FI unit, of course it all needed to be sanded down and polished & than sprinkled with a little Chrome. Didn't set well with the Corvette crowd even back than......................................

 

Never could figure out why that guy installed 2 air intakes, you would still have to be able to drill out the orifice's to a larger size. Would be interesting to hear what Jr. Stock did if anything to "hop the FI up"..............

 

That was one of Zora's better ideas.....

 

Wayne...I have a 63 fuelie and cannot get the Economy and Power Stop settings right on the Fuel Meter. I have set it up using a Miti-Vac based on a 1982 article in NCRS and it worked fine...but 15 years later it surging after I rebuilt it on startup.....Like to purchase a wideband air fuel meter but not sure how to set it up...do you take the readings when driving and come back and make adjustments afterwards or do the adjustments while in the garage. Thanks...Larry

 

They were definitely better than a 4 barrel, but they were not perfected and not enough mechanics were prepared to work on them! I put one off of a 57 Chevy on my 63 Impala SS with a 300 HP 327 and it made a noticeable difference!

 

I have been off the H.A.M.B. for awhile, but when I saw this topic, I thought I had to respond even though the thread is a year old. Warning, this is rather long.

Back in 1961, I went to high school with the son of Joie Chitwood, who was a sprint car and Indy car driver back in the 1930’s and 40’s, and ran an Auto Thrill Show. In 1961, he was in about the 6th year of a 50 plus year association with Chevy. They got new cars for the show each year and Joie Jr drove a 61 Fuelie Corvette (315 HP 283) to school.

That Spring, we hooked up and took the Corvette to the drags at old York US 30 in York, PA. I learned to tune the Fuel Injection, even getting the Manometer to calibrate it. I must have been lucky since we always won. We even beat another Corvette tuned by Bill Jenkins, twice.

I had met Bill Jenkins a couple of years before when he was doing tech inspection at the old Lancaster drag strip. I say Bill Jenkins, because back then his nickname was Jiggs. I don’t know when the “Grumpy” came into being, but he was always polite and answered this dump teenagers questions.

One weekend Joie’s Dad went to see us race. After winning again, he offered me a job as a mechanic with the thrill show. That began a 4 years association with the show and a life time association with Joie Chitwood.

Now for some Rochester Fuel Injection and Corvette stories.

The biggest problem I every had with them is the fuel pump drive cable shearing off. The fuel pump was driven by a cable from the distributor. We always tried to carry one in the glove compartment of each vette (they used 2 in the show) and one in my truck.

One time we were making a hop from a Saturday night show somewhere near Fonda NY to somewhere that escapes my memory in Maine for a show Sunday afternoon. (We didn’t get a lot of sleep back in the day). Somewhere on the Mass Turnpike, one of the vettes sheared off the cable. For what ever reason, there was no spare in either glove compartment. They towed one Corvette behind the other with a seatbelt chain the length of the turnpike.

Back in those early days, the junk cars used in the show were stripped of all glass, gas drained, 1 gal put back in, and holes punched in the floor behind the driver seat. A short piece of chain was looped around the frame rails and bolted to old WWII aircraft seat belts. So they were towing less then 3 feet apart.

They parked the disabled vette at the toll plaza at the end of the Mass pike, and I didn’t see it when I drove by, so I had to drive back 150 miles or so to repair it.

The only other Fuel Injection problem we had was due to bad gas. The show would usually have a gas deal in each town where some local distributor got advertising plugs in exchange for 300 gallons of gas.

We never had problems with carbureted cars and trucks, but twice, the Corvettes started missing like hell. Turns out the injectors, all 8 of them, have small screens in them that got clogged. Taking them out and apart in a field was no fun, especially when I dropped a piece that took over an hour of searching to find.

That’s the only Fuel Injection stories I remember. I do have a couple of Corvette stories you may find interesting.

It had to be early in the Summer of 1961, I was driving one of the Corvette’s (Joie SR’s) between shows following Joie JR in his. Somewhere in the outskirts of Dayton, OH, he stopped for a stop sign. I didn’t. Opps. I may have the distinction of being the only one to wreck to Fluelie Corvettes at the same time.

Minor body damage to both, but broke the aluminum radiator in SR’s. Finding someone in 1961 that could weld an aluminum radiator was a chore. Surprised I was not fired on the spot. Needless to say I was driving a truck after that.

In 1962, Joie SR flipped his Corvette in the first turn at Hamburg NY with the guardrail coming down between the windshield and his head. He didn’t get a scratch, but his wife who was there was not thrilled. A lot of fiberglass to patch with duct tape.

In the Winter of 1963 (in addition to building and campaigning a Z11 Impala), I built roll bars to install in the 1963 Corvettes. I must say it was some of the best fabricating I think I ever did. I had to find a place in Tampa that could bend 1 ¾ inch tubing.

I will add that Joie Chitwood III went on to be President of Indy and later Daytona.

 

Dad took me to see The tournament of thrills at Capital Speedway must have been back in the late 60s early 70s.
I sure would like to hear more about campaigning a Z11.

 

RG, I remember seeing the show clearly. Must of have been a thrill to be part of it.

 

@rgclouse, you win. That’s the post of the week AFAIC

 

I Have Run 5 Rochester Injections On My Autos Since 1975 And Always Read The Books Each Time...

 

That's really neat Lou, how about some engine details, I see power pack heads, is that a 283 or 327?
Car looks to be a 64 or 65 Chevelle.

 

It Is On A 39000 Original Mile 1964 El Camino With 220 HP 283 And Factory 4 Speed...Thanks DDDenny....

 

Lou, thats a beauty.
I had an original 327, 4 speed 65 El Camino in the early 70's, a very fun car.

 

I Have Always Liked The "Short" 1964/65 El Caminos And Using The Chevelle Makes Them Just Right...

 

I stumbled across this yesterday when refreshing my mind on the Rochester Fuel Injection. I can't remember the HAMB rules, but will post the link any way.

By the way, thanks for the positive feedback on my post.

Will download a PDF.

https://www.google.com/url?sa=t&sou...FjAAegQIAhAB&usg=AOvVaw1R_J2g79jU28osYvgaAwG2

 

Bought a 57 Nomad last weekend that came with a 58 fuel unit that I would like to install. Missing the distributor. Any one have a line on one of these? I notice the distributor opening has a roll pin installed in it. Does the distributor have a slot or a just a hole? I realize you have only so much travel until the drive cable runs out. Might be a chore to get the base timing where you want it.

 

Most will appear to have TWO speedo cable drives , one for tachometer, and one for the fuel pump on the passenger side of the unit. (Drives are diff than speedo though) adjustments are tunes with a manometer (uses inches of water)

 

'58 Vett's had the tack cable run off the generator I believe.............................

 

Your right I played with 63-65 units

 

Shouldn't mater to the OP when installed in his NoMad......................................

 

The distributor will have a cable drive for the fuel pump.

 

Had this one many years as mentioned earlier-ran strong for a 283-097 cam, close ratio 3 spd 3:70 posi--never had many issue with it. Only time was when on vacation with the kids in Tahoe and it wanted to foul plugs a bit at that altitude-change plugs and go!!
This car was a drag car from new until about 61. At one point it had a 4spd in it when NHRA allowed them. When I bought it it had the 3 spd but the 4 spd was with it-was a Jan 58 dated unit-sold it for serious $$$ a few years ago.. The last time we redid the car I had a FI expert rebuild it-he has done over 200+ units. He called me after I got home and asked where this unit came from as it had some things he had never seen. After some research with the other FI gurus at the time he determined the air meter was from one of the 5 units designed for Cadillac in 57 but never saw production and was overstamped with a Chevrolet number. He also said the nozzles were some he had never seen before as well and a few other things that were a first for him. After it was done we went up there and he had the unit on his 60 corvette and had run it thru all the tests. He took me for a ride and we took it off and came home. The odd thing he did and said they did alot years ago was to run it with the cable from the dist with no housing! Crazy but stayed put as he drove it around. He has done quite a few around here-some are the later units and are on Hot Rods etc.