97 4.3 swap to gen 3 4.8 or 5.3 how to??????

[mercuno]

It is a 1500 with 4l60 tranny and we want to do a basic swap? Cheap is key. harnesses computers exhaust etc etc. I need an idea for a cheap as all get out v-8 swap help...

[ducky]

Check out the LS1 conversion forum index. That has ALOT of information on how to do OBS swaps to gen III engines. Part numbers are pinned, the actual swap is pinned, and a BIG thread on other misc information for the OBS swap is in there. Hope you find what you need.

[skeet]

i did a 99 4.3 to a 5.3 its not that difficult did it in a weekend.. you will use one motor mount from the v6 and one from the v8 the computer can be reflashed from the 4.3 but i got everything posible when i bought the 5.3 the exhuast will bolt right up to the 4.3 exhaust at lease mine did... i didnt have to change nothing.. or had no problems but like i said i used the 5.3 wiring harness and computer ..


heres a tip if this motor has been sitting up for a long period of time, pull the fuel rails clean them very well... one huge problem that i had ...also clean the injectors ... but as for the swap was perfect...

[mercuno]

99 is nbs new wiring configuration and everything. I cant find anything on the 97 obs style 4.3 to gen 3 swap. Will I need a wiring harness or will the one that comes with the motor work the stock guages??? I can get the motor com and nbs harness for 800. what about the a/c comp and the alternator? Exhaust and o2 sensors? the 4l60 should work just fine with it correct? has anyone done anything close to this.

[kwkenuf]

Your swap is not different from the others that have been accomplished and documented on this site. There are far too many variables for someone to answer all your questions in one post. Search this forum and you shall find the info. Yes, you are going to need to do some wiring, the NBS engine harness will not just plug into your 97 system. You will need to identify circuits, and splice /connect as required. You will also need to work on the fuel system. Additionally, there are two types of O2 sensors, get the ones that come with your motor and they'll plug into your harness. Get the head pipes and brackets from your donor vehicle and you may be able to splice into your existing exhaust system for not much money. Purchase an engine as complete as possible (with all accessories), it makes things much easier. A/C compressor mounting is a problem for some, not insurmountable however..... Again, the info is available to you with a quick search in this forum. There is lots of info in the stickies and RedHeartbeat has composed a very good primer on what things you need to consider to get this swap done. After you have done your research and you have specific questions on how best to handle a particular problem, ask away in the conversion forum and you'll get lot's of quick and hopefully helpful advice. This will not be a "cheap as all get out V-8 swap" but you can minimize your expenses somewhat through good research and parts selection. Good luck with your swap!