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Charlie Yannetti · 06-10-2021, 08:11 AM

I'm running a 1250 by DC Carbs on my 565, but I have a bit more HP than you, and my car is almost 1000 lbs lighter than yours.. I just don't have Tom's compression at 14.5 to 1.. on the stop my O2's get to about 13.9 to 14.1 or so.. I also changed from VP C-14+ to VP X-14 with positive results... no tuning changes, and picked up 1 MPH..

I have also been told by many that 1250 is un-necessary on my combination, and that a 1050 or 1150 would probably work better.. next test and tune, I'm going to back to back my 1250 with the renovated 1150 from my 522 motor.. bigger isn't always better, but some carb builders go by HP numbers.. at 1004 HP, I would say that 1250 is not for you, especially at 3000 lbs..

Running lean while on the stop is kinda the norm, but if you're banging bearings, and possibly hurting the crank, I'm not thinking that running lean for 2 to 3 seconds is your problem.. but that's just me..

06-10-2021, 08:11 AM	#8
Charlie Yannetti Senior Member Join Date: Jan 2005 Location: Alpine, NJ Posts: 557 Likes: 178 Liked 179 Times in 77 Posts	Re: Throttle stop carb adjustment I'm running a 1250 by DC Carbs on my 565, but I have a bit more HP than you, and my car is almost 1000 lbs lighter than yours.. I just don't have Tom's compression at 14.5 to 1.. on the stop my O2's get to about 13.9 to 14.1 or so.. I also changed from VP C-14+ to VP X-14 with positive results... no tuning changes, and picked up 1 MPH.. I have also been told by many that 1250 is un-necessary on my combination, and that a 1050 or 1150 would probably work better.. next test and tune, I'm going to back to back my 1250 with the renovated 1150 from my 522 motor.. bigger isn't always better, but some carb builders go by HP numbers.. at 1004 HP, I would say that 1250 is not for you, especially at 3000 lbs.. Running lean while on the stop is kinda the norm, but if you're banging bearings, and possibly hurting the crank, I'm not thinking that running lean for 2 to 3 seconds is your problem.. but that's just me..