Page 1 of 2 12 LastLast
Results 1 to 10 of 20

Thread: Once again fiat 48 rings true.

  1. #1
    Blown 472
    I have a similar B!-BS that made? so I will say 550 to 590 without knowing if the cam is a roller and not knowing which fuel or spark plug and jetting you are using. BTW I have seen a motor dyno,ed on two different dyno,s on the same day loose 40 hp by switching dyno,s. The first was a Superflow and it broke after cam break in and three pulls to seat the rings.(the motor was a 318 truck spec. roundy round motor) We pulled the motor off of the Super flow and was able to drive 20 miles to the east to Vrbancic Bros and use thier DTS that afternoon. The altitude and weather were the same but the motor made less HP and torque on the DTS. Go figure, was the Superflow optimistic or was the DTS stingy?
    I,ll never know for sure. The bottom line is we are not racing dyno,s so the true test and measurements are found at the race track IMO!
    From the moparts site.

  2. #2
    LakesOnly
    Stopwatch! Period!
    LO!

  3. #3
    Blown 472
    Originally posted by LakesOnly
    Stopwatch! Period!
    LO!
    For those of us brave enough to take our shit to the track and not just talk smack online.

  4. #4
    Fiat48
    Just for fun, here is a time slip of my old car (L702) and my present car (7246) running side by side, just screwing around at a local track. Both altered roadsters, blown alcohol, and both tuned to run a mid 7.50. Object of the game here was to tune both cars to run close to 7.50 but not under. That's the way we qualify in nostalgia. Once we are qualified, we squeeze the 2nd qualify run close to the 7.50 as we can.
    http://www.***boat.com/image_center/...x_755_-med.jpg
    Here are the run conditions: Static elevation=4100 ft. Corrected altitude = 6511 ft.
    Both engines BBC 475 inches. Both 6/71's Blown alcohol. L702 has 1 full point more static compression (13 to 1). Both run same camshaft, ignition system, 34 degrees timing and same injection system. Cylinder heads are different. Both cars weight within 75lbs of each other. Both powerglides. Both are tall decks, both use a .400 long rod and a trw type piston.
    L702 runs a 33x17x15 tire with a 4.86 rear end gear. 8 3/4 Chrysler rear end (I knew Blown472 would like that part). Tune up is 2% underdrive on the blower. 80 pill. Nice new tires on this car. Cylinder heads are Brodix BB2 xtra pocket ported only.
    7246 runs a 34.5x17x16 tire with a 4.70 rear end gear. 9 inch ford (Lakesonly likes that part). Blower is 24% overdriven. 40 pill. Old tires. Cylinder heads are fully ported Chevrolet solid aluminum open chamber D port.
    Using the old power and speed calculator and figuring each car at a weight of 2100 lbs = 990 hp.
    I'm gonna let Blown 472 think about this.

  5. #5
    Blown 472
    That is interesting due to the fact the winning car had a slower mph, bigger et, and it looks like it was won on the starting line as he had a better reaction time. The sixty foot is killer, those cars must hook pretty damn hard. Less gear and and less blower and still runs within two mph. hummmmmmm
    How do you keep that 8.75 alive, all the stuff I read says they wont take a bunch of power or maybe cuz your stuff is not heavy?

  6. #6
    Fiat48
    I've run 7.20 at 190 with the little 8 3/4 Chrysler. We blew a few rear ends till we found the problem. The gears are too hard. An old drag racer/machinest told me to deburr all sharp gear edges, then heat the gears in an oven at 450 degrees. Then quench immediately in cold water. Since we did that, we never lost another gear set. Yeah, a light car helps a lot.
    Fuel racers in the old days ran the 8 3/4.
    The 60 ft of the L702 car is: new tires and more gear.
    The more MPH at 1/8th for the 7246 car I attribute to higher gear and larger tire has more growth. Also a factor at the finish line.
    But the biggy is 2% underdrive in the L702 car and 24% overdrive in the 7246 car to run 7.55 e.t. While the L702 car has a bit more compression, it's the cylinder heads that make the difference. It's all about cylinder heads and there's the proof.
    The L702 car will run 7.50 at 18% underdrive at Bakersfield (2500 ft corrected air) while the 7246 car takes 4% overdrive to do the same job.
    Reaction time? I thought I would be polite and let him leave first.

    I wonder about this 990 HP. And if it's rear wheel HP. I don't know.

  7. #7
    Blown 472
    Interesting. Polite? hehehee
    How is your altered set up? you have a driveshaft or is the tranny coupled right to the rear? does the rear move or is it solid?

  8. #8
    Fiat48
    Both are solid suspended cars. Short solid drivelines I'd guess about 18 inches long. L702 is a Neil and Parks chassis and 7246 is an S&W chassis. Both built in 1991.

  9. #9
    Blown 472
    Cool, thanks. That is interesting about the heads, a fully ported vs a pocket port dealio and the pocket port out flows the other. You forgot the boost numbers, heheheee

  10. #10
    Fiat48
    About 10 lbs on the L702 car and 17 lbs on the 7246 car. But we don't know how accurate the boost gauges are. And L702 gets better fuel mileage.

Page 1 of 2 12 LastLast

Similar Threads

  1. Hey fiat
    By Blown 472 in forum Gear Heads
    Replies: 7
    Last Post: 06-04-2007, 10:05 PM
  2. Replies: 30
    Last Post: 05-08-2007, 08:22 PM
  3. Hey Fiat,
    By Blown 472 in forum Gear Heads
    Replies: 3
    Last Post: 03-25-2006, 06:30 AM
  4. Hey Fiat 48
    By Blown 472 in forum Gear Heads
    Replies: 26
    Last Post: 07-23-2005, 05:25 PM
  5. Hey Fiat
    By Blown 472 in forum Gear Heads
    Replies: 4
    Last Post: 02-09-2004, 08:12 PM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •