setting up three 94's for a Y block ?

Ralph Moore

Ralph Moore

Well-known member
I'm setting up some early 94's (model 91-99) and I'm looking for a good place to start from as far as jetting/power valve combinations go. Engine will be mostly stock(maybe a mild cam) with center dump headers. Intake is an Offy. I plan to pull the chokes out of the two end carbs. Anyone had experience with this?

Thanks,
Ralph
 
You have really picked just about the best 94 you could for a tripower setup as long as they are all 91-99's.
Don't let anyone fool you, you have a lot of hours to look forward to making these 94's better than new and will spend upwards of $200 just to buy the parts to make them that way..................and if someone else tells you different..................they don't have a clue!
I have set up a few tri-power setups over the years and it sounds like you are just getting started on the motor, so my first recommendation would be to go through the carbs.........and this means tearing them down all the way, soaking them and replacing any parts that look like they are worn, lap all of the body surfaces on a known flat plate, use premium gaskets form Charlie Price in Florida..................this will not be cheap but will be the only to ensure you get a tri-power setup that will work right out of the box and continue to work for a long time.
I would suggest turning the secondary carbs into dumpers, no power valves and no idle circuits. Then put some 12 degree throttle plates in the secondaries, and a 5 degree throttle plate in the primary. The primary is the only one that will receive a choke, but when you pull the chokes out of the secondary carbs make sure you plug the holes in the top of the carb horns.............without doing this you will screw up the air coming into the carbs and tuning this setup will become almost impossible..................a 22 caliber shell casing does this nicely, but don't let it protrude into the venturi, it needs to be flush. You will need a good progressive linkage, and don't with that cheap crap from Elco or Speedway. I know a lot of people on this site are going to say it is OK, but it is cheap crap and you can't get the precise settings you need. Either contact Flathead Jack or one of our very own members, Strombergs97, Duane.....................who makes some of the best linkages known to man..............IMHO
If you need more information just give me a PM or we can continue here if you want. I think if you search my postings you will find that I have gone over this subject before................but if you want help just let me know.
 
I've already got a good start on most of what you posted. Bodies cleaned, flat sufaces faced, chokes removed from secondaries and plugged(nice idea to use the shell casing), I had several carb plugs left over from other kits that worked good. Do you plug the idle circuits, or just run the screws all the way down? What # jets do you run in primary, secondaries? How did you plug off the power valves? Setting these up for a friend, and my mistake his intake is an Edelbrock 553. After I get done with these I plan to set up a triple for my 52 Merc engine using early Chandler Groves 94's.
 
Ralph,

I have always used epoxy to plug the idle circuits and then sanded them down on the outside and inside............here is a picture of a mockup I did awhile back for a 312 Y block. As for plugging the power valves, you can buy plugs through Holley that work fine. If you don't want to have a perminantly filled bottom base (filling the idle circuit with expoy) you can just screw the needles into the seat, but you really need to lap the needle and seat to get a perfect seal, if you don't they will leak.
As for the jets, what cam will you be using, that is the important part.
 

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Looks like the same setup, Thanks for the advice, I've rebuilt plenty of carbs, but I've never done a dual/triple setup before. So it's going to be a learning experience for me.
 
I suggest that you leave the choke plates in for better air flow direction..Old myth to remove them..Of course if your running WOT all the time then it's OK to remove..
Duane..
 
Ralph,

You heard it from (stromberg81), what happened to strombergs97 Duane.
Duane is a good buddy and here in California we call him Mr. Stromberg as he has rebuilt hundereds for customers all over the world.
But, on the 94's............at least the secondaries, take the choke plates and shafts out............just make sure to plug the holes.
On jet sizes, it really depends but a good place to start is 50/52's in the primary and 46/48's in the secondaries. Don't forget to set this up as progressive and when you do, bolt the bases to the manifold, install the linkage and make sure everything is working as it should before you bolt the rest of the carb tops on...................this way you can see the throttle plates and make sure they are fully open and fully closed. You should also start to bring the secondaries in at about 70% throttle.
Here are some pictures of the last one I did for a guy back on the East Coast. Notice the NOS Thermostate housing, and the bases were cad plated along with all the linkage..............
Good luck and post pictures when you are done.
 

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Seems to be some discussion about the choke plates, IMHO I would think the plate left in would restrict flow, even if ever so slightly. I can see your point though, when the guys were hitting the salt back in the day it was WOT all the way.
I also think the main drawback to leaving them in is what would happen if one ever got closed on you when you were tooling down the road?
\
Another question, I've noticed on my carbs that I have two different styles of bowl vents, one to the outside air, and the other with a venturi to the carb throat. Sort of an early emission control, will it make any difference mixing these up, or should I plug it(and drill same as others), or use the venturi style for the Primary carb?
 
Bump, went to the local NAPA and was able to pick up the power valve plugs made by MR. Gasket, can't believe they had them in stock.
 
Ralph,

I think the "myth" about leaving the choke plates in was only aimed at the 97 style Strombers. The Strombergs do run better with their choke plates in and remember the Stromberg and 94 are totally different carbs. I have set up quite a few 94 tri-power setups and they performed great...reading the plugs is the true test and driveabilty are the key issues and since the secondary carbs are just dumpers...........take the choke plates out. While we are talking performance, don't use those cheap paper air cleaners, use the good K&N filters(I think they are 3202's)...............sure they are three times more money but the flow 50% better and will last forever.......and be aware that all air cleaners are not alike............some are considerably more restrictive than others............sure they look neat, but will they flow the air needed????
As for the small differences in bowl vents......................that will make no difference in setting up the carbs, run them the way they are; when you start plugging holes and redrilling them you never know what or how that will affect the carb..............leave them alone.
I know where Duane is coming with not to remove the choke plate since he is Mr. Stromberg here in California, but again this really applies to the Stromberg. If you have had any dyno time with fooling around with carbs you will see that removing the choke plate does (in any Holley carb) will help with performance, and in some cases you can actually see the difference in HP/Tq numbers......in this case you may or may not, but remember that an internal combustion engine is nothing other than an "air pump", the more good air you get in is hardly ever bad, and don't forget about good air cleaners and air filters...............then getting the bad air out is the job of a good set of headers.............................the first picture is a set of headers I made for a flathead, and the second pair is off my 70 Maverick Drag car....a well though out pair of headers can add as much HP as the tri-power setup...................................IMHO
 

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It may be awhile, but I'll let you know how it performs. All carbs, especially performance/racing require some tweaking to get it to perform the way you want it. At least in my experience.
 
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