Cable Posted July 24, 2008 Share Posted July 24, 2008 Hey guys, starting another project car but this time I want something dependable and something that wouldn't kill my mpg and still have a decent amount HP/TQ. After weighing cost (among other things) I decided on swapping in a 5.3 Vortec engine. Today I bought a complete setup (engine, computer, harness, MAF, etc) from a rolled low mileage 2004 Burb. I already have the engine mounting handled, so that's out of the way. I will prob end up running full length headers too since it looks like I would have to trim too much of the stock frame to make the stock manifolds work. I did not buy a transmission so that means the TH350 tranny I have will be bolted to the 5.3. I did several searches and found that the stock computer will need to be tweaked to work for me (I figured). I have read that the un-used inputs can be 'edited' off the computer and I have also read something about 'pinning'? I made a list of things that would not be used in my case, but I am fuzzy on how this is done..... (please explain both). -VATS -EGR -Speedo input from trans -Rear O2 sensors (no cats) Okay, lay it on me. What else do I need? Any help is thanked in advance. Thanks guys!! Quote Link to comment Share on other sites More sharing options...
mark Posted July 24, 2008 Share Posted July 24, 2008 You need a VSS input to the computer. It usually comes from the tranny. TH350 does not have that sensor. Quote Link to comment Share on other sites More sharing options...
deja Posted July 24, 2008 Share Posted July 24, 2008 You can eliminate the VATS feature in your PCM and remove the VATS module. But if you want the added anti theft protection this is how the VATS works. There are 4 inputs to the VATS, +12v always, +12v ignition switched in run and start, ground and 2 inputs from the resistor on the ignition key. There are 3 outputs, the security light, fuel pump enable and start relay enable. If you don't have the correct key nothing works! If you still want to use the VATS measure the resistor in the Camaro key, make a resistor to substitute for the key and installed it across the 2 wires that would normally connect to the Camaro ignition switch. I used a quick disconnect so I can remove it when I want to fully protect the car from theft. To eliminate the EGR all you need to do is block off the fitting on the intake. Not sure about the 5.3 but its pretty simple on an LT1. There are a few controls and hoses you can pull off as well, check a shop manual for your engine. You will also need to eliminate it from you PCM or it will pull a code. EBay had block-off plates but it’s easy to make your own, all you need is a steel or aluminum plate, a gasket and a couple bolts. Again I don't know about the 5.3 but on the LT1 once the engine is in the car you can't see the plate anyway so it doesn't have to be real fancy. Sorry no clue on the rear O2 sensors, my LT1 doesn't use them. But you live in Ccalifornia, don't you need to pass smog stuff? If so won't you need the cats? Quote Link to comment Share on other sites More sharing options...
mark Posted July 24, 2008 Share Posted July 24, 2008 Rear O2's can be turned off in the PCM. Quote Link to comment Share on other sites More sharing options...
Scottie-GNZ Posted July 24, 2008 Share Posted July 24, 2008 Good choice on the 5.3L. Best bang for the buck right now. Seems like a TH350 is contrary to your concern about mpg. If you look hard enough I am sure you can find a 4L60E for a decent price and cover some of the cost with selling the TH350. With a 3.54:1 and the TH350 and an optimistic 6% converter slip, that 3.54 is more like 3.75:1. With the 4L60E in OD and lockup, the 3.54:1 is more like 2.48:1. If you do any kind of highway driving, you will easily make up the extra cost of going to the 4L60E. Quote Link to comment Share on other sites More sharing options...
Cable Posted July 24, 2008 Author Share Posted July 24, 2008 Good choice on the 5.3L. Best bang for the buck right now. Seems like a TH350 is contrary to your concern about mpg. If you look hard enough I am sure you can find a 4L60E for a decent price and cover some of the cost with selling the TH350. With a 3.54:1 and the TH350 and an optimistic 6% converter slip, that 3.54 is more like 3.75:1. With the 4L60E in OD and lockup, the 3.54:1 is more like 2.48:1. If you do any kind of highway driving, you will easily make up the extra cost of going to the 4L60E. I guess I should of added this isn't going into my Z. Its going into my '69 Chevy shortbed fleetside. It has 3.08 gears and 29" tall tires. The TH350 is a 'C' model (lockup converter). Thanks for thinking of that regardless. Quote Link to comment Share on other sites More sharing options...
Scottie-GNZ Posted July 24, 2008 Share Posted July 24, 2008 I guess I should of added this isn't going into my Z. Its going into my '69 Chevy shortbed fleetside. It has 3.08 gears and 29" tall tires. The TH350 is a 'C' model (lockup converter). Minor missing details That combo should do well for mpg. As my sig states, I am building a 98 Sonoma Stepside with an LM4/4L60E. There is a company in the Tampa area that builds custom harness and makes the ECM mods for that swap. Just got that stuff in the mail today so I am itching to get going. Quote Link to comment Share on other sites More sharing options...
Cable Posted July 24, 2008 Author Share Posted July 24, 2008 Minor missing details That combo should do well for mpg. I agree. I still might add the correct 4L60/4L65e down the road, just not today. Are you going to run the drive-by-wire setup or retro-fit to the cable style? I am keeping the drive-by-wire on mine since I grabbed the pedal and control box for it. Besides, one less thing on the firewall. I love the look of a clean and shaved firewall. If I could, I'd run the master cylinder and booster along the frame rail to keep it off the firewall too. Quote Link to comment Share on other sites More sharing options...
Scottie-GNZ Posted July 25, 2008 Share Posted July 25, 2008 Definitely doing DBW. I grabbed the pedal from the donor, 04 Trailblazer EXT, but it is HUGE so I will have to rig something up. Quote Link to comment Share on other sites More sharing options...
Cable Posted July 25, 2008 Author Share Posted July 25, 2008 Definitely doing DBW. I grabbed the pedal from the donor, 04 Trailblazer EXT, but it is HUGE so I will have to rig something up. Really? Mine is smaller than my '69 factory pedal. You might search around for a truck pedal or a car one for that matter. From what I read they all interchange with the connections and computer sensors. Quote Link to comment Share on other sites More sharing options...
Basic Posted August 15, 2008 Share Posted August 15, 2008 Really? Mine is smaller than my '69 factory pedal. You might search around for a truck pedal or a car one for that matter. From what I read they all interchange with the connections and computer sensors. I'm surprised you're using the TH350. There won't be any problems with a difference in bolt pattern between the LSx Gen III block and a turbo 350 tranny? If that's the case I'd be more than happy to test fit a T-5 on my 5.3. Quote Link to comment Share on other sites More sharing options...
Cable Posted August 15, 2008 Author Share Posted August 15, 2008 I'm surprised you're using the TH350. There won't be any problems with a difference in bolt pattern between the LSx Gen III block and a turbo 350 tranny? If that's the case I'd be more than happy to test fit a T-5 on my 5.3. It will bolt up with 5 of the 6 bolt holes on the tranny. I would also need a flexplate spacer from GM. However, since first posting this topic I scored a 2004 GTO 4L65e & converter with 13k miles on the clock for $800. Quote Link to comment Share on other sites More sharing options...
Basic Posted August 15, 2008 Share Posted August 15, 2008 Can you elaborate on the GM flexplate spacer. I just dug up some good information to reference regarding using this tranny, but I did find out there's about 3/8" to be negotiated to space out the flywheel from the engine. Do you know a specific part number for the flexplate spacer? Quote Link to comment Share on other sites More sharing options...
Basic Posted August 15, 2008 Share Posted August 15, 2008 Is this the flexplate spacer you're talking about? http://www.crateenginedepot.com/store/LS1-Flexplate-Spacer-12563532-P1343C0.aspx Quote Link to comment Share on other sites More sharing options...
mobythevan Posted August 15, 2008 Share Posted August 15, 2008 Yes, that is the spacer. I used it to run a 700r4 on my 5.3 last year. I am now using it to run a powerglide behind the 5.3 Quote Link to comment Share on other sites More sharing options...
Cable Posted August 27, 2008 Author Share Posted August 27, 2008 Engine/trans installed: http://www.ls1tech.com/forums/showpost.php?p=9999014&postcount=3 Quote Link to comment Share on other sites More sharing options...
Pete84 Posted August 29, 2008 Share Posted August 29, 2008 Looking good. Time to start shopping for some forced induction? Quote Link to comment Share on other sites More sharing options...
Cable Posted September 2, 2008 Author Share Posted September 2, 2008 Well I got the modified PCM and harness back from Wait4Me and plugged everything back in today. Still have to mount the PCM somewhere on the driver's side, prob on the inter fender well. I also have to wire up the the harness for stand-alone operation (3 ignition switched and 1 constant 12 volt) fuel pump and relay. Quote Link to comment Share on other sites More sharing options...
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