New to the site, with questions
Thread Starter
Teching In
Joined: Sep 2015
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New to the site, with questions I'm working on putting a 2002 4.8 and 4L60E in my 64 Chevy truck. I have an LS 1 intake, aftermarket fuel rails with EV 1 injectors. I'm using the truck accessory brackets, LS1 water pump with spacers and relocated to pulley below the alternator. I have the dbw throttle body that I would like to use. I bought a pedal, GM # 25835421, and after more research, I'm not sure if it's compatible. I'm thinking of buying a kit with computer, harness, tac, and maf. When I called, the tac module was quoted at $400ish and they suggested I go dbc. Is there another throttle body I could use or is it easier to change to dbc ? I'd so, what throttle body should I look for and what is being used for the throttle linkage and bracket ? Thanks. Links to any of these questions are appreciated. There is so much information here, just haven't found the rights threads yet. Thank you !!
TECH Fanatic
Joined: Jun 2014
Posts: 1,533
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What are u running for an ecm? I would call psi conversions . They sell harnesses, ecms, tuning ect... They should be able to help you out. In order to go dbw you are going to need a gen 4 harness, ecm, throttle body, etc . But these run off a 58x reluctor and u have a 24x . Call them they will point you in the right direction.
Last edited by jimmyg; Mar 10, 2016 at 08:25 PM.
If you don't have the TAC module, corresponding pedal, ECM and the throttle body you're definitely better off going DBC. From what I remember, they all have to be from the same vehicle to work right and as you already know, the parts (especially the module) are big money.
On The Tree
Joined: Nov 2010
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From: Fairview , MO
OK you will need the tac module that has the metal/aluminum mounting feet, the short wiring harness for the module to gas pedal and the gas pedal from a 2003-2006 Chevy truck. Also the throttle body if you don't have one already. Your harness should have the blue and green connectors that are bolted to the pcm if it does then you're good to go if it has the blue and red connectors which it should being it's a 2002 then it's a drive by cable setup and that harness won't work without some rewiring. Of course your harness will still need to be reworked to run in your truck but those are the parts you will need for dbw . You will have to do some work on the gas pedal to get it to fit in your truck because the way it is bent it will hit the transmission tunnel. I would look at your local pick and pull or salvage yard and see what you can find before spending a lot of money on new parts.
We need to know exactly what all you have. Is your 4.8 DBW? Sounds like it is, if so, then you need the all plastic TAC, the aluminum base one wont work with the older systems. A lot of parts can be found in junk yards on the cheap.
If you've got a 2002 4.8, it's most likely a DBC throttle body system. Your LS1 intake is a DBC also, as long as it's actually an ls1 intake (3-bolts for the throttle body).
At this stage in your process, I would say track down a 3-bolt throttle body and buy an aftermarket harness for an LS1 as that will probably be your simplest route.
DBW systems require a lot of specifics.If you already have an ecu for that engine, it most likely will not work with a DBW throttle body without some weird repinning and tuning. A lot more headache than it's worth.
Could you tell us more of what you have already?
At this stage in your process, I would say track down a 3-bolt throttle body and buy an aftermarket harness for an LS1 as that will probably be your simplest route.
DBW systems require a lot of specifics.If you already have an ecu for that engine, it most likely will not work with a DBW throttle body without some weird repinning and tuning. A lot more headache than it's worth.
Could you tell us more of what you have already?
Thread Starter
Teching In
Joined: Sep 2015
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Thanks for all the replies. After more research and talking to PSI, turns out my DBW theories body is actually a 2003 model. I do have to use a different pedal than the one I bought previously. I ordered harness and all the goodies from PSI. My friend sprayed color and matte clear on the motor and transmission yesterday while I finished with body mounts. Next step is moving the crossmember forward to center the front wheels,fabricate the rack and pinion mount.,motor mounts, and start reassembly.
