If the weather cooperates I'm going to try to get to the track on Friday with the new combo. I've been running a 750 VS on the street but I'd like to switch over to my 650 DP for the track. Can anybody recommend a good starting point for the jetting on the 650? My full combo is listed in my sig. Car weighs 3380 with me in it and I will be running 26" BFG drag radials. I may or may not run with open headers.

Thanks!

Chris

Start with the stock jets on your 650 DP --- you can go to the Holley site (look for numerical carb listing) and look them up but I think they are 65F/73R if I remember correctly. If you go to open headers you might need to go step richer and maybe use a bigger accelerator pump cam too.

If you did go and look at Holley’s numerical listing you saw that there was a wide verity of jet sizes used on the 4777 alone not to mention all the other models. I would probably start at 71’s in all four corners and adjust from there to correct for altitude, temperature and what Eric68 said about open headers.

In a routy 400, at 600 feet above see level, with open headers, I used 72’s all the way around in a 4777-0. There really isn’t a 4777-0, but mine was so old it had no suffix.