FAST "Crank Box"

Reply Subscribe

Thread Tools

Search this Thread

Nov 29, 2004 | 08:24 AM

1point3liter

Thread Starter

TECH Regular

Joined: May 2003

Posts: 404

Likes: 0

From: Jacksonville, FL

FAST "Crank Box"

I've done a good bit of searching on Fast's crank sensor decoder, but i haven't really found any literature on it. I haven't even found a website that lists it for sale.

Anyone have any information on it? A place where I can pick one up online maybe?

Nov 29, 2004 | 09:29 AM

RX-Ben

TECH Apprentice

iTrader: (7)

Joined: Jun 2004

Posts: 372

Likes: 0

From: Brooklyn

Call up FAST. They don't know much there, but it is better than nothing.

The box will give a hall effect signal @ 60 BTDC which is what most standalones require for a trigger angle. Depending on your fueling strategy (batch vs. sequential) you will also need a cam sensor. I tried to find when the stock cam setup gave its signal, but I was never able to get a response.

What is your proposed setup?

Ben

Nov 29, 2004 | 09:45 AM

1point3liter

Thread Starter

TECH Regular

Joined: May 2003

Posts: 404

Likes: 0

From: Jacksonville, FL

Thanks, I'll give them a call.

I'm looking to use an AEM ems with a turbo ls1. I don't have a lot of experience with crank triggers to be honest, but i'm determined to learn and make this work in the process.

This may be a n00b question, but what exactly do people mean when they refer to a 4x signal? How many teeth does the LS1 crank have?

Nov 29, 2004 | 02:38 PM

Pro Stock John

LS1Tech Co-Founder

iTrader: (34)

Joined: Nov 2001

Posts: 45,364

Likes: 1,797

From: Chicago, IL

Kurt @ W2W sells them, his email address is kuperf@aol.com.

He also has a lot of crank trigger experience.

The FAST is 4x.

The LS1 is 24X if I recall.

LS2 is 60X.

Nov 29, 2004 | 02:41 PM

1point3liter

Thread Starter

TECH Regular

Joined: May 2003

Posts: 404

Likes: 0

From: Jacksonville, FL

thanks, but what exactly do you mean by 4x, 24x, 60x etc... What variable does the numerical value stand for.

Nov 29, 2004 | 11:02 PM

RX-Ben

TECH Apprentice

iTrader: (7)

Joined: Jun 2004

Posts: 372

Likes: 0

From: Brooklyn

The numerical value is the times per revolution that a crank signal is put out.
Most standalones require 4 outputs per revolution, at 60 degrees BTDC though some have adjustable trigger angle.

I'm assuming you are considering the generic AEM? They have really missed the boat by not offering an LS1 compatible piece but it would be difficult for any standalone to mirror the capabilities of the factory PCM.

Why would you ditch the stock computer?

Ben

Quote:

Originally Posted by 1point3liter

thanks, but what exactly do you mean by 4x, 24x, 60x etc... What variable does the numerical value stand for.

Last edited by RX-Ben; Nov 30, 2004 at 12:27 PM.

Nov 30, 2004 | 11:34 AM

Pro Stock John

LS1Tech Co-Founder

iTrader: (34)

Joined: Nov 2001

Posts: 45,364

Likes: 1,797

From: Chicago, IL

Merging AEM and FAST stuff sounds difficult, good luck on that.

Trending Topics

Nov 30, 2004 | 11:58 AM

dynocar

TECH Enthusiast

Joined: Sep 2004

Posts: 564

Likes: 0

From: Omaha, NE

Quote:

Originally Posted by 1point3liter

thanks, but what exactly do you mean by 4x, 24x, 60x etc... What variable does the numerical value stand for.

The numerical stands for the number of trigger events per crank revolution. Being a 4 cycle engine requires 2 crank revolutions to complete a full cycle a 4X will give you 8 trigger events to complete fireing all 8 cylinders. The 24x, 60x etc are used in vehicles that test for misfires by comparing the the number of triggers per time at a given RPM, the PCM sorts out the required 4x for each cyl. Not only can they diagnose a misfire, this can also tell you what cyl it is, neat. Most standalones such as FAST and Accel/DFI require a 4x trigger signal. AEM can be programmed for many others. Electromotive supplies their own trigger wheel etc.

EJ