tuning the dual quad

[enrico]

Just got through installing a rebuilt 425 in my riv but i don't think i've got the carbs just right, especially now that i'm running a little bit of a cam in the new motor. Does anyone out there know a reputable carb/race shop in the southern ny/northern nj area that might be able to help?

[Bob]

Just a suggestion from someone who lives a long way from good automotive services...

I would look for a tuning shop that has a dyno and is willing to spend a little time setting everything up. This expect this could take a few hours, but would probably be worth it in the end.

There is not such equipment within 3-4 hours of where I live, so I have never been exposed to one, but I do believe they are the way to go, especially with a modified engine.

Maybe someone else has some good input here...

[enrico]

I had that done on my corvette when i lived in ohio, and man did that motor sing a different tune when they were done with it. they not only tuned the carb but also changed the weights in my distributor to match the timing curve to my cam. BIG BIG difference!

[Dr. Frankenbuick]

Enrico,

You might also want to drop in on a local 1/4 mile track on a test and tune day. Run back to back tests with different timing, timing curves, jetting, plug gap and shift points. Change one thing at a time and keep everything else consistent. When changing jetting, make sure to jet down if the MPH slows down when jetting up, and jet down to or up to the best MPH. Island Dragway is in Great Medows in northern NJ.

Tom Telesco is in Staford, CT at Classic and Mucsle Automotive - 203 324 6045. He is a Nailhead guy with a stock 64 Riv in the 13s. Tom helps out with Bob Quigg's 401 powered 11 second 66 GS Skylark. This car has an Eedelbrock b262 2x4 set-up, but Bob and Tom have tested all kinds of carbs and manifolds, jetting, timing and parts on this car. He can point you in the right direction.

Dyno tuning is helpful, but not without error. Tire slip and heat soak can point you in the wrong direction. Comparisons of the numbers from the same dyno on different days may not be reliable, and comparisons of the numbers on different dynos even on the same day will not be valid. Make sure to use the same dyno when evaluating changes over time, and back it up with a few runs at the track to be sure it is making a positive impact. It is easy to get a tune in the ballpark, but it can take years to get everything tuned perfectly. Don't get me wrong as my Cobra is dyno junkie. The computer control of most events in that car, and computer changes can be made in 5 minutes. This means back to back runs are for the most part consistent. Proof positive for me is still improvement at the track, but the dyno can be very useful. It is also a lot of fun!

[enrico]

thanks for the info...I will be giving him a call. I am really looking foward to getting the proper ponies out of the motor as I love driving this car.