Page 2 of 2 FirstFirst 12
Results 11 to 14 of 14

Thread: Twin Turbo 408 Ford - Cruise AFR at 12.8:1?

  1. #11


    Skip to post #13 to get right after making your table:

    Also, use this page to determine where your intake closing point really is to properly apply IEA to your cam:

    Race engines are easy. I just use one number and apply to the whole table so injection always ends before intake closing.
    There's a bunch of math to do to make sure your WOT IPW fits in the intake valve open window, but it's not too hard to calculate it.

  2. #12


    Had a chance to drive the car. Bumping the Injector End Angle from -90° to -180° smoothed the cruise out and it's happy at 14.2 AFR. I'll give that IEA table a go as well. Thanks for all the suggestions.

  3. #13


    Yeah, the Injector End Angle can make a really big difference at idle and low speed operation. I watched a tuner change the IEA on a race engine once and it went from sounding like a top fueler to almost a stocker. The car ran the same number down the track, but before the Injector End Angle was adjusted the car couldn't be driven around the pits. After adjusting the Injector End Angle the car could be easily driven around the pits and the track performance stayed the same.

  4. #14
    Join Date
    Nov 2014
    Ont. Canada


    Here's what I did with my IEA: Then alan5oh refined it and came up with some spreadsheets to make it easier.

Page 2 of 2 FirstFirst 12

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
About us
Holley has been the undisputed leader in fuel systems for over 100 years. Holley carburetors have powered every NASCAR® Sprint® Cup team and nearly every NHRA® Pro–Stock champion for four decades. Now, Holley EFI is dominating the performance world as well as our products for GM's LS engine. Holley's products also include performance fuel pumps, intake manifolds & engine dress–up products for street performance, race and marine applications. As a single solution, or partnered with products from other Holley companies - Hooker Headers, Flowtech Headers, NOS Nitrous, Weiand, Earl's Performance Plumbing, or Diablosport - Holley products can give you the edge you need over the competition.
Join us