Its a 850 double pumper carb running on a 12.8:1 compression HYd roller cam 408.
4200 stall and 4.56 gears out back.
Now this stumble started show it ugly head the first of this year. And Every Holley book and YOUtube i have watched say if it stumble at the first of the full throttle stomp. YOU NEED BIGGER SQUIRTERS.
I started out with what can in the carb, which is 31's, then 33 and seamed to fix the problem......
next race had the same stumble problem so i when to a 35 and stumble when a way............
Last race had same problem and when to a 37. problem solved and ran good again. Vary confused but fix the problem so well ok.................
So today i install my 90/10 shock up front and put my GoPro back under the car to see how the 90/10 work.
Guess what!!! Yup the stumble is BACK.
Now one more tidbit before you watch the video. I made sure there was 0 play between the squirter arm and lever. secondary need a slight adj and figured it was going to run even better. But NOOOO
With all of this i don't' think the Squirter is the problem, but what is?????
You can watch the hole video but the "drive and stumble" is about 1.30 into the video
If i roll the throttle in it works just fine. but if i stab it, it stumbles........
Your primary shot pump my be going to hell, hence the change in running characteristics.
What cc shot pump do you have? Have you checked the pump diaphragm?
I had to go to a 50cc shot pump on my BB stroker to lose the stumble.
Sounds like it's running out of fuel
