LS-2 Conversion Fly by Wire Concerns?

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Dec 8, 2009 | 03:24 AM

81fastvette

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From: Vancouver Wa

LS-2 Conversion Fly by Wire Concerns?

I am considering doing an LS-2 swap into my All Weather DD and have concerns about the Fly by Wire throttle body, would hate to have it go WOT or fail when needed most! Can a wire driven LS-1 throttle body be used on a LS-2 or would this require a specially programmed ECM?

Dec 8, 2009 | 06:42 AM

Matt Gruber

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From: central FL, near the beach.

Edelbrock makes a dual plane. Then u could use a 4165 Holley Double Pumper, which will get about the same mpg, and u can avoid that expensive to repair efi. Plus u get that cool sound WOT. The timing module comes with the manifold.
The reasons LSX get great mpg:
low friction rings
roller rockers
roller lifters
cam desiged for mpg
excellent timing control
low hp oil pump
efficient exhaust
electric fan turns ON at 228F, not before!
steep overdrive .50 is helped by efi, but if u don't have more than .70 OD, efi won't make a significant difference.

Last edited by Matt Gruber; Dec 8, 2009 at 07:40 AM.

Dec 8, 2009 | 08:09 AM

KENS80V

Melting Slicks

Joined: Aug 2004

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From: Oakbank Manitoba

Quote:

Originally Posted by 81fastvette

You can use a cable driven LS1 throttle body but you will also need a LS1 or LS6 intake manifold. The LS1/LS6 manifold will bolt right up. Also I'm sure the aftermarket makes cable driven throttle bodies to fit a stock LS2 90mm manifold (although they are pricey). A program from a 2002 Camaro would be a good tune to start with if you have a 24 tooth reluctor. Be careful with your choice of LS2 motor as there was an early 2005 version with a 24 tooth reluctor and a later model with a 58 tooth reluctor.

Last edited by KENS80V; Dec 8, 2009 at 08:13 AM.

Dec 8, 2009 | 08:19 AM

Garys 68

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My Nissan pickup has DBW, it's a lot more common than you think. I've got a 6.0 LQ9 out of an escalade with DBW in my 68 vette, no problems. Look at the schematics for DBW, it's triple redundant with the sensors.
Add to the other problems in converting to cable, the fact that the TB acts as the IAC with DBW.
Use the DBW and dont worry about it.
Oh yeah, and you can even have the pedal/throttle response programmed with it too.

Dec 8, 2009 | 08:22 AM

Gordonm

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From: Forked River NJ

The drive by wire has been around for years and has worked very well. I would not be concerned at all with it. I was driving an LS7 resto mod over the holiday weekend and it works very well. I would keep the LS2setup and drive it.

Dec 8, 2009 | 09:14 AM

7T1vette

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From: Crossville TN

Drive-by-wire throttle systems are designed to fail with the throttle going closed. The worst that will happen would be that the car would slow down and roll to a halt. It won't even shut the engine down...but just goes to an idle condition. If the wire breaks, it senses a No Throttle condition.

Auto designers take lots of precautions with how systems fail just so drivers/vehicles don't have accidents because of system failures. Where individual owners get into problems is when they start modifying such systems and DO NOT take those conditions into account. You are much better off utilizing a complete system rather than 'piecemealing' it.

Last edited by 7T1vette; Dec 8, 2009 at 09:17 AM.

Dec 8, 2009 | 09:15 AM

SteveG75

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From: FL

My 2003 Avalanche has DBW. 47,000+ miles with no issues. DBW works well. Another small advantage is that it is very easy to use cruise control since it just requires a VSS and some switches to activate.

Go to www.ls1tech.com for lots more info.

Dec 8, 2009 | 09:26 AM

jackson

Le Mans Master

Joined: Sep 2001

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From: Unreconstructed, South Carolina

fly by wire is not as responsive as cable. Reference endurance racers. Take a look at Schwanke Engines of Springfield MN. They've been marketing real race LSx motors for quite a while. More recently Schwanke's ASA Transcontinental motor is based on LS3, has GM fuel inj, GM CoP ign, GM ECM (reprogrammed) and THROTTLE CABLE. Those will power some ex cup cars at Phakisa 1.5 mile D-oval track at Welkom (near Jo'berg) South Africa; ASA races there late Jan 2010.

One of these pieces was prepped at a local shop & I got somewhat familiar w/ it; it left last week for SA.

I dunno what all's involved coverting to hard cable; above motor came from Schwanke as package w/ all hardware (even elec fuel pump & reg) & cable.

http://www.phakisa.com/html/asa_racing.html