Originally Posted by conceptfab
I have been calling around to have my carb modded for blow through and i get prices from $450-$1100. Thats a big difference and one thing i have learned is you get what you pay for. These are all big companies too. The one big difference is i hear that over 1000-1100 whp you need to go to dual needle and seat fuel bowls and thats what the double in price is for
Yes fuel volume capacity is real important as you approach that power range especially if you run E85 or plan to in the future. IMO you could run two small Holley dual feed carbs to get enough needle area and probably improve on air/fuel distribution while your at it.
One of many reasons for not running a Qjet in blow-thru mode is the limited needle area and small bowl capacity.
Think about this... it takes @ 6000 lbs/hr air(@ 100 lbs/min) to make 1000 HP.
Turbo'd the fuel required would be @ 525 lbs/hr or 8.75 lbs/min.
Pump gas varies some but 6.01 lbs per gallon is typical.
So... 1000 hp will use @ 87.35 gal/hour or @ 1.46 gal/min fuel flow. Thats a bunch of fuel to move through a needle seat assembly.
That is primarily the reason for the dual needle bowls on the big HP blow thru carbs.
BTW I've heard no evil when it comes to CSU's blow thru carbs!