The Cal-look Lounge

Cal-look/High Performance => Pure racing => Topic started by: Jon on March 30, 2007, 15:17:18 pm



Title: 12 sec with STOCK fuel pump?
Post by: Jon on March 30, 2007, 15:17:18 pm
Can it be done, or is it just one of these things you hear about, that can't be done?
I love the way the old race engines look, especially, the Inch Pincher look with the stock pump. I hear you can "blueprint" them, are we talking about making sure the rod has no play before actuating the "leaver"? I thought about moving the pump 1mm over to move the rod closer to the pivot point to get a higher ratio on the lever.

Did anyone play with these things back then? 
 


Title: Re: 12 sec with STOCK fuel pump?
Post by: Alan Uyeno on April 01, 2007, 07:40:11 am
I would guess a stock pump can provide enough fuel to the IDA's as long as the fuel inlet is opened up and larger needle/seats (3mm) and an opened up float bowl is used.

If your car uses E85 fuel I'd say NO WAY!!


Title: Re: 12 sec with STOCK fuel pump?
Post by: Jon on April 01, 2007, 23:38:52 pm
Thanks for the replies, I have a pair of 3mm valves laying around. But before I go this route I will do some "field tests". The hard part is to figure out how much it delivers on 6000-7000 rpmīs.


Title: Re: 12 sec with STOCK fuel pump?
Post by: Alan Uyeno on April 02, 2007, 01:03:03 am
According to mallory a 200HP engine can use upto 46gph with a dead head regulator with electric fuel pump. I'm assuming theres safety worked in with that sort of calculation.

If you have 3mm n/s and opened up float bowls you might be fine. The little cavity in the IDA thats opened up is aproximately an ounce more of fuel so thats just a good bump in capacity.

6000-7000rpms will only occur for short durations of time in the 1/4. You might just be fine. An a/f meter would indicate lean fuel deprevation if you can data log. If not you'll probably feel a slight nose dive at the end of each gear.


Title: Re: 12 sec with STOCK fuel pump?
Post by: ovaleasy on April 13, 2007, 03:54:37 am
I have run in the 12:30s @108 mph with a stock fuel pump and unmodified 48IDA's.
Motor size was 78X89 in an average weight street car.


Title: Re: 12 sec with STOCK fuel pump?
Post by: Jon on April 13, 2007, 09:54:19 am
Impressive Ovaleasy!
Did you you modify it in any way?


Title: Re: 12 sec with STOCK fuel pump?
Post by: ovaleasy on April 13, 2007, 16:53:52 pm
No. The only modification to the fuel system was a vent for the tank.


Title: Re: 12 sec with STOCK fuel pump?
Post by: RhoadsVW on May 08, 2007, 01:11:21 am
With a stock fuel pump in the 70's Mark Hunsaker ran a 12:30 with an IDA motor built by FAT Performance.
       Dave Rhoads