Torn old school or new school

[autonaut]

My 78 Malibu 400 sbc runs fine, gets about 10 mpg, mid 14's in the quarter. My '96 Impala SS gets twice the gas mileage, has run 14.7 with headers, cat back etc, has no problem smoking those big tires. I had a 4.3 V8 '94 Caprice for a winter car. It's driveline( trans, harness, etc.) plus a 5.7 LT1 long block will provide the next driveline for the Malibu this winter. Maybe not as good as an LS, but you can buy a 94-96 B body car for under $1000 these days and with the Malibu 4-600 lb. lighter it should be a nice driveline. It should be capable of 13's in the quarter and get the same gas mileage as my Olds Silhouette van. I have done a couple of LT1 swaps (62 Pontiac, 56 Ford) and this one looks easier.
Pete

10mpg hitting 14's in a malibu is not good. Something is wrong here!

 

[lilbowtie]

Autonaut - I'll second that!

 

[rwd_pete]

Late '60s muscle car era cars typically got 10-15 mpg just driving around. The 400 engine has a Crane 272 cam, Performer RPM intake and 750 Holley, but smog heads. I drive it back and forth to work, not much highway. It might get 15+ mpg on a trip.

I had a 2.5:1 first gear 4 speed, but to improve econonomy went to a 2.41 rear with a 3.5:1 first gear three speed. With that setup the car ran 14.6 @ 94 without getting to third gear. When I put the 400 in it I blew the spider gears in the 7.5 witihin the first 1/2 hour doing some testing. Leaving easy at the track on the 7.5, wheel hop had the 275/60s getting chunked with the front fender edge so I packed it up after two runs. It still gets crappy mileage even with 2.41's.
The Vortec package is similar to the LT1 regarding head flow, roller cam etc. Both can make 400 hp without too much effort. The Vortec easier to install, The LT1 more complex to install, but will get better fuel economy. I installed a 4 barrel on one LT1 installation, but still had to use electric fans and an electric fuel pump. In hind site, I think I should have just left the injection on it. It has a GM hot cam and I was concerned about computor tuning.
I'm just getting my Impala SS winter ready and then the Malibu gets parked for the winter and I'll start the swap. LT1/4L60E. Although a '78 doesn't need e-testing here, the car still is supposed to have all of the 78 equipment... no EGR on a Performer RPM. Fines are $325 per missing item. So the plan is to make it emssion compliant after the swap because I don't see the laws getting any slacker.

 

[Redline007]

I actually have and old early 80s 350 from a suburban with a 700 r4( needs rebuild but runs), 350 in a 70 Monte Carlo (runs), transmission is shot, and lastly a vortec 350 out of a 99 I think ( no trans with it and some rust on piston and cylinder wall). Is there a combo I should put together from these parts? Also how much would a full engine and head rebuild run me at a machine shop?