Posted By: None2Slow
Which carb for a mild d/d 360? - 08/21/10 10:37 PM
I have 2 different carbs that I can use. 1 is the 80457 (600 vacuum secondary) and the other is 80508 (750 vacuum secondary duel feed). The car is going to be an automatic with a factory h/s torque converter. The motor is a .030 360 with 10:1 piston, .484 purpleshaft and the heads have been rebuilt with 2.02 valves and some mild cleanup. The rear gears are about 3.25:1 with a 235/60/14. This is going into a 63 Valiant convetable. The car will be more of a weekend cruiser and just to drive around when the weather is nice. I will also make a couple trips a year to the track and the occasional exhibition of speed, but for the most part, just a fun car. Looking for the better of the 2 for power and mileage. Either way, I need to put a kit in whichever I use, so I am looking for which would be better to use.
Posted By: MoparforLife
Re: Which carb for a mild d/d 360? - 08/21/10 11:01 PM
The 600 would be fiine but myself I would use the 750 vac and jet i t accordingly in the front. It will only use what it needs for secondaries. Vac secondaries are great for the street.
Posted By: mark7171
Re: Which carb for a mild d/d 360? - 08/22/10 03:15 AM
Bigger carbs work well for me. The vacuum secondary holleys never see full cfm potential, unless you are reving that 360 out to 7000. A 77o vacuum secondary holley SA would be nice, a 650 DP is good, 600 edelbrock is a drop on that would provide incredible throttle response.
On my 318 the 770 street avenger worked fine with a stock silver spring. At 5000 rpm it flew about 650 cfm.
Posted By: None2Slow
Re: Which carb for a mild d/d 360? - 08/22/10 04:01 AM
How does the throttle response for the 750 compare to the 600? I would guess that the 600 would get a better jump off the line from a stop light to light run. Is the 750 going to be a little more lazy until it gets moving? Maybe sell them both and get a 700? I may be able to get a 650DP. Would that be a better carb then either of these? Any input is welcome.
Posted By: forphorty
Re: Which carb for a mild d/d 360? - 08/22/10 06:25 AM
I'm getting a little off topic here,but i think the 484 cam is a little much for a factory high stall converter. Will probably contribute to laziness off the line more than a slightly oversize carb will. I dont know what that 80508 carb is. If it is similar to a 3310, run it.
Posted By: MY340
Re: Which carb for a mild d/d 360? - 08/22/10 03:32 PM
600cfm better mileage probably?
750cfm definitely more power!
I'd go with the 750cfm for sure.
