4l60e vs 4l80e
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4l60e vs 4l80e Hello all new member here, I'm rebuilding a 69 firebird and have been on the fence for a couple of years regarding the engine, it currently has a 400 with th400 in it but I was always thinking of putting an ls in it. So the decision has been made I'm currently rebuilding a LQ9 6.0l but dont have a tranny yet....my question is this, can I slap a 4l60e on this engine or should I put a 4l80e. This will be a street car not really raced or driven hard, i might put the pedal to the floor once in a while. Looking for advise on weather the 4l60e will hold up to the 6.0l. As far as hp goes I will keep the 319 heads 10.1 compression ratio maybe mild cam but pretty much stock might try to get 400hp out of it. Thanks
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Ok thanks, stupid question here (get used to it I got lots) my LS is from an 03 silverado, my buddy has an 4l80e from a 1992 gmc 3500 would this fit or should I be looking for one from a gen III vehicle, also would a 4l80e fit in my 69 firebird?
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I don’t think it will work... maybe wrong. A built 4l60e will last, but I think it depends on your budget. If you’re talking a stock 60 vs a stock 80, I’d go with the 80 for insurance. Especially since it’s a street car and you’re not overly concerned with extra drivetrain weight.
If you are going to drive it, put a 80e in it. 60e's are a rabbit hole. I have thrown good money after bad on 60e's because I was told a "built" one will last. My trans is now a 65e with all the built ****. Truck lays down about 430hp NA and my 65 lasted about a year before the problems started creeping back up. The 80e is going in SOON!
