70 L-46 to LT1 conversion

[Dennis D.]

Wondering what would need to be changed. I think the bottom end is the same. 186 heads,same.

Different intake, carb, dist., cam, lifters, 2 1/2 exh. Anything else?

[Chas Kingston]

Re: 70 L-46 to LT1 conversion

Swing gate pan
No P/S
Machine the heads for screw-in studs
Tach face
console plate
Fuel line
Stamp pad

to name a few

[Warren F.]

Re: 70 L-46 to LT1 conversion

Transistor Ignition set up, big block hood.

[Dennis D.]

Re: 70 L-46 to LT1 conversion

not looking to make a fake LT1. Leave my pan, so PS will work. Tach and plate not needed. Fuel line on the driver side I didn't think off. I do have a LT1 tank though. Thanks

[Dennis D.]

Re: 70 L-46 to LT1 conversion

Hav a L88 hood (extra). Know about the ignition. Have a msd with a box might work

[Joe L.]

Re: 70 L-46 to LT1 conversion

Dennis------

The short block is mostly the same. The only difference is the cam and lifters. Cam required for the swap was GM #3972178 and lifters were GM #5231585. Both are discontinued. However, a clone kit of cam and lifters is available under GM #12364054.

Most 1970 LT-1's used the standard "5 quart" Corvette small block pan (i.e. the one without the "trap door" baffle). Some early 1970 LT-1s MAY have used the "6 quart" pan and all ZR-1 used the 6 quart pan.

Cylinder heads are the same except that LT-1 used screw-in studs and L-46 used press in studs. Some L-46 may have received screw-in studs, though.

Exhaust system is the same for both engines. Both used 2-1/2" exhaust

Intake manifold, carburetor, and distributor are different, of course.

Fuel supply line for both engines is on the right side, although the configuration of the front end of the lines are slightly different for L-46 and LT-1. No need to change the line, though, for a functional installation. LT-1 fuel pump is different than L-46.

1970 LT-1 without EEC (i.e non-California) used NO fuel return line. So, there was only a fuel supply line and no other line, at all. The 1970 L-46 without EEC used a fuel return line on the right side (same side as supply line). For an LT-1 conversion, this line would be unused and capped.

1970 with EEC (i.e. original California car) used an additional vapor return line on the left side for BOTH LT-1 and L-46.

[Dennis D.]

Re: 70 L-46 to LT1 conversion

Joe

sealed or vented cap for the non eec LT1?

[Joe L.]

Re: 70 L-46 to LT1 conversion

Dennis-----

ALL 1970 Corvettes used a sealed fuel cap regardless of engine and regadless of whether they were EEC or non-EEC.

Late 1969 Corvettes (after about July, 1969) could have used a sealed cap, too. However, all 1969 models were originally fitted with a vented cap.