'77 Nova swap 6 banger for v-8

Looking at swapping out the 6-banger in my '77 Nova for probably a 350. What kinds of mod's, if any, am I going to need to take into consideration? I'm getting ready to basically rebuild the front-end and all the parts (ball joints, bushings, etc.) seem to be the same regardless of engine size. Some specific questions:

1) Wondering if the springs are the same and if I should beef up the stabilizer bar?
2) I think the motor mounts will work (that is, I wont need to do any welding/cutting, etc.)?
3) It has an auto trans which I'm assuming ( ) it's a Turbo 350 and will mate with a 350?
4) Need to swap out the rear-end? Not sure what the gearing on it is. Is there a relatively easy way to find out? It sure seems to wind out now - don't know for sure if that's the gearing or because it's just a 6 cyl?

Anything else I need to account for, please advise.

Thanks,
Jag


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I've done this same swap to a '76 so I can give you some pointers. The motor mounts on the frame remain in the same place, you will just need the metal "shell" engine bracket(motor mount cup) for a '75-87 SBC car. Truck mount cups are taller and won't fit correctly. Trans behind the six is more likely to be a TH250 (mine was) so look at it close. A TH350 will bolt in its place with no trouble. The six cars frequently came with the spindly 7.5" rear(mine did), but the V8 Nova or Camaro/Firebird 8.5" rear is a bolt in. The 7.5 is easy to identify by the two 3/8" long "fangs" that stick down from the casting below the rear cover at about the 4 and 8 o'clock position. The 8.5" will have a 1", square cornered 1/2 block at the same spots. Distributor and alternator wiring will need to be re-routed, and the power steering pump will need to have it's brackets changed to V8 type. Alternator and starter can be re-used, you might have to change the throttle cable. I was building a street/strip car so I left the sixer front springs in, and it did sit low with a V8. Sway bar was the same as a V8 car, if you want a bigger one look to the '70-81 Camaro/Firebird. The rest (belts. hoses, etc.) is stock V8 Nova. It is a pretty easy swap, done in a day if you have all the parts.

hi there

well, 77 seems to be the oddball year in that the th350 did come behind the 250 engines. i had a 77 250 nova and it had the t350. i can look in the gm data options ordering sheets for the 77 novas that i have here and make sure. regardless of the trans though it will bolt to any chevy v-8 engine.

have fun

http://novaresource.org/axle.htm is a good reference source for Nova drive trains. The "rules" were sometimes broken, however. Occasionally, due to parts availability problems, they would use a stronger rear or trans than spec called for, in order to keep the assembly line operating, but it was only once in a while.

http://www.oldsmobility.com/10bolt-tech.htm has pics of how to tell an 8.5" rear from a 7.5".

The Camaro/Firebird 8.5" rear will NOT bolt into a Nova. It's too wide, and the spring perches are too far apart.

My last ride before building this Corvette, was a '70 Nova. While it was a V8 car to begin with, (307) and had the auto matic trans, I went through a lot of drive train changes after selling the 307 and building my 350.

First, I went through a couple of Turbo 350 transmissions. I had the OEM one built twice until it blew up on a 6500RPM 1-2 shift. Then I went to a Turbo400 and never had another issue. I had to get a different driveline made for the 400.

Then I blew up the OEM 7.5" Rear end. Many pieces. I got a 12-bolt housing from a Gen1 Camaro, to replace the ol' 10 bolt with. Yet another custom driveshaft of course. BUT - That drivetrain lasted for years under much abuse. I ran 4:11 gears and let me tell ya: That Nova ran like a rocket! Wish my Vette was as light and as immune from SMOGGING as that good ol' Nova. I miss it.

That '70 Nova was a great & fast car. I drove it through 7 states before selling it.