cobra30689

Hello! Newbie here.....

Eyeballing a '83 Z28 with an L69. Wondering if there are any caveats with replacing the L69 with a 350 keeping the E4ME and computer, as I am primarily concerned with proper transmission operation (700R4). Aside from mixture control, are there any other functions of the ECM that require a retune (if there is such a thing) for a larger engine with possible modifications (I haven't decided WHAT I want to do to the new engine yet)?

t/aws61985

iTrader: (2)

I'd keep the l69. They are almost non existent anymore. Never see them for sale and when you do they always have a 350 now.

midias

Lots of good info here

http://www.early3rdgen.com/forum/viewtopic.php?t=25

1987L69

If you do swap a 350 everything will swap over, some people will say you need a knock sensor for a 350 because it will have a different "harmonic tune" to the block but I have seen the 305 ones work in a mild 350. If I were you personally I would keep the 305 if you decide to swap it, just put it in a corner of your garage and forget about it until you decide to sell the car if you ever do

86LG4Bird

iTrader: (1)

Keeping the E4ME and computer is the right thing to do IMO. All the extra performance with very little hit in fuel mileage
See my sig. As long as the cam is mild, the carb will adapt just fine.
Again, depending on the cam, you might want a more aggressive timing curve. I'm running a stock L69 chip in mine.
The trans works just like stock.
If you do headers and end up with your O2 sensor in the collector, run a heated one. I'm running the stock sensor with TPI manifolds.
I just used the stock knock sensor, but I really don't rely on knock sensors in any of my motors.

dmccain

iTrader: (2)

Like 86LG4Bird said pretty much a straightforward swap. I agree the 750 Quadrajet will be plenty for a mild 350. While you are doing the swap get a better torque converter if nothing else get an s10 converter in there for less than $200 it will be worth it.