Hi All, I've searched the archives but never really found what I was looking for. I have a stock Model A engine and a Burns twin carb intake. I've heard Stromberg 81's are the ideal carb set for this engine, due to the fact they flow at 125 CFM. I have a pair of Holley 94's, and have also been looking at Stromberg 97's due to their availability as well. Questions for the community... 1) Would the twin Holley 94 carbs be "too much carb" for this application, or can you toy with the jetting to make it work? 2) With the Strombergs, the 81's flow at 125 CFM and the 97's flow at 150 CFM. Do you think the 97's would work, or the best bet being to snag a set of 81's? If the Holley 94's or the Stromberg 97's would be fine, can anyone share their jetting success (and power valve selection for the 94's)? I'm getting ready to tear into the Model A and just want to make sure the selection isn't too much for the engine and it's enjoyable in the end. Thanks in advance! Jake
My first RPU had the stock engine when we bought it. It had a two carb intake with two 97's, and a Delco-Remy distributor. It ran awesome for a 4 banger. I would go with the 97's. Can't tell you what the jetting was. Never had them apart.
Fighting this right now with my 2 Carb'd Banger. Dual 97's down jetted. The engine is slightly bored out, has a cam of some non stock spec, high compression head and electronic ignition. Due to my own lack of experience in tuning these things I am going to a single carb set-up. I have had fuel in the oil and inconsistent drivability. When it is running good it is fun. Again I may be inducing this. This set-up has been run by man before and have great results.
A single carb will give better low end drivability. I guess it depends on the engine speed your going for and other mods. I'm building a 28 Chevy motor bored to take A pistons, I have no intention to rev over 3000 RPM with splash oiling and old Babbitt so a single carb will benefit this. Twin carbs would lose low end and only come to good effect where I would risk losing my engine. For me my cam grind and fuelling etc is all geared towards low end torque. Forget looking pretty. Limit your build to how strong the bottom end is. Sent from my iPhone using The H.A.M.B. mobile app
1961 a friend had a dragster with a 4 banger in it and it had 2 97s on it and for his needs they worked fine. For the street I think the 81s would be fine.Do not run more than 2.5 to 3 lbs of fuel pressure on the Strombergs. Make sure your power valves are not leaking down to contaminate your oil and if using the stock fuel tank use a shut off valve.
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