'70 Nova L78 (nicely documented)

[WILMASBOYL78]

RPO-L78 Novas in 1970.....total produced 3765. The L78 top end was basically identical to the LS6 454 motors. Heads were the newer 291's with larger valves..2.19 int...1.88 exh. They both shared the same cam, carb, TCS and low profile intake. The other major difference from 69 was the actual CID of the motor...though labeled a 396, they were actually 402's. Lots of theories on why...I will let others debate that. Some guys I know claim the low profile intake hurt performance and many switched back to the 163 or aftermarket in the day. By the way...I know that 69 green car quite well and one of it's prior owners... almost bought it..sorry I didn't...nice car..good luck!


wilma

[deuce-less]

speaking of 70 L-78 novas....

i can't believe that fathom blue car is still available!!

awesome color, it looks just right

[deuce-less]

if you can, pm me the info you have on the prior owners...

did you get the pic's over the weekend on the th400 car??

i am interested

thx, alan

[YENKO DEUCE REGISTRY]

[ QUOTE ]
RPO-L78 Novas in 1970.....total produced 3765. The L78 top end was basically identical to the LS6 454 motors. Heads were the newer 291's with larger valves..2.19 int...1.88 exh. They both shared the same cam, carb, TCS and low profile intake. The other major difference from 69 was the actual CID of the motor...though labeled a 396, they were actually 402's. Lots of theories on why...I will let others debate that. Some guys I know claim the low profile intake hurt performance and many switched back to the 163 or aftermarket in the day. By the way...I know that 69 green car quite well and one of it's prior owners... almost bought it..sorry I didn't...nice car..good luck!


wilma

[/ QUOTE ]

Never really noticed that the 291's had bigger valves, or that the LS6's had the short intake. Do these differences translate into a noticeable power difference between the '69 vs. the '70?

[WILMASBOYL78]

I don't have any dyno info to document the difference, just "street" feedback from guys I knew. The low profile intake was supposed to be a method for better hood clearance on the Corvette and perhaps Camaro. I would think that the larger valves might take a little off the bottom-end, but on the 454, with all that torque, it probably wouldn't be noticed. Most cars with these type engines had pretty strong rear gears which kept the revs up in the power range. I have never driven an LS6 car but I do know that the L78's really come on once you hit 3,000 rpms. Love to hear those solids sing!!!

wilma

[Schonyenko2]

I was not impressed with my 70 L78. It didn't run as well as 69s. Seemed way nose heavy compared to other earlier L78s I've driven. Best L78 nova I ever drove was a 68. My deuce would have ate my big block alive.

[Salvatore]

SB ate your BB alive! Thats impossible Mayor. Only reason I can figure is that the First Lady must have been driving the Deuce and you the BB car.

[47Hammer]

Maybe he forgot to release the parking brake on the BB.

[Schonyenko2]

BB was before the 1st lady Sammy. She got 1 ride in it before I hit the bridge with it. I don't know why it wasn't quicker than it was. I lost races with it, that I won going away with the deuce to the same cars. I never had a chance to tweak it. I'm sure headers, and some M/Ts would have helped.

[Bill Pritchard]

My friend Rick's 70 L78 Nova was a dog bone stock....ran like low 15's. Add headers, dual point distributor, 4.56 gear and presto, high 12's.