Engine exchange from 261 to 350

Bake · Member

Engine exchange from 261 to 350

73SC · A Poncho Legend!

So is this 350 a Pontiac or Chevrolet engine. 1967 was the first year for a Firebird and a 350 was not installed from the factory so what do you have?

dualquadpete · Canadian Poncho Superstar!

Lets hope it's a "chevy block" or if a US 350 blue block you have the trans as well??? Chevy will drop in with just getting frame engine mounts or possibly just moving the 6 cyl. frame mounts to V8 location? If it's a US 350 Pontiac engine wiring will have to be shifted to opposite side for starter & likely Alternator, exhaust will have to be "custom built" Driveshaft frt. yoke changed to fit newer transmission!!!!

73SC · A Poncho Legend!

dualquadpete wrote:
Lets hope it's a "chevy block" or if a US 350 blue block you have the trans as well??? Chevy will drop in with just getting frame engine mounts or possibly just moving the 6 cyl. frame mounts to V8 location? If it's a US 350 Pontiac engine wiring will have to be shifted to opposite side for starter & likely Alternator, exhaust will have to be "custom built" Driveshaft frt. yoke changed to fit newer transmission!!!!

Well Pete, if its a Pontiac engine my advice would be don't do it. As you say a Chevrolet is a fairly straightforward task.

long stroke · Canadian Poncho Superstar!

Why not just keep that trusty reliable 261 and the Power Glide with lots of character and save your self all that money converting to a boring run of the mill power plant.

MC · Canadian Poncho Superstar!

long stroke wrote:
Why not just keep that trusty reliable 261 and the Power Glide with lots of character and save your self all that money converting to a boring run of the mill power plant.

Agreed. The 261 has lots of torque and should move the car along quite well. In fact the US Pontiacs didn't even come with a 6 in '60, IIRC, so that makes it even more unique.

Just my opinion, but it's your car to do with what you wish of course.

Bake · Member

OK folks,
Thanks for the input. I've had lots of others suggest that the 261 is worth keeping.
As for the 350 I'm looking at, I'll have to do more research before I step ahead.

My thoughts on upgrading the engine is so that I can have a daily driver with the advantages of fuel injection and electronic ignition. The best of both worlds is a sturdy old car with an up-to-date power train. Doesn't that make some sense?

Prefectca · Poncho Master!

That makes more sense. What year Firebird, your first post says 66, do you mean 06?

Paul

-- Edited by Prefectca on Tuesday 24th of September 2019 12:00:11 PM

dcneric · Poncho Master!

I build the car for me. It's your car to enjoy as you see fit.

An engine swap can always be a challenge. When getting the donour powertrain try and get as much of extra parts, wiring harness etc that you can. If possible, get the engine block and the frame mounts and even the trans cross member. Some cutting and welding can generally modify most mounts to work on your specific application.

Best of success on making your car more daily driver friendly.

73SC · A Poncho Legend!

We are having a hard time with Firebirds fellas, Production ran from 1967 to 2002 so there is no 66 nor 06. Anyway, the idea of a late model drivetrain is kinda cool in a 60 Vista roof. In fact decent power always changes the drivability of any car for the better.

-- Edited by 73SC on Tuesday 24th of September 2019 01:17:03 PM

MC · Canadian Poncho Superstar!

If you're going the hot rod route, then the most no-brainer to get lots of power and modern fuel injection seems to be the LS swap. Lots of donors out there and lots of info on the net. It's so popular there are even kits available to make it easy (well, easier): http://www.brphotrods.com/products/58-64%20B%20body%20products/index.html

Lots of info out there on the net - this '60 Biscayne swap can probably tell you most of what you need to know, since under the skin they are pretty much the same car:

73SC · A Poncho Legend!

Wondering about what the outcome on this thread, sure would like to know what engine is contemplated for this swap.

lonesome Polecat · Newbie

hi everybody first post:
It has been decades since I had my 1961 Laurentian, but it is important to remember that the Jobmaster 261 came with a truck transmission, and if manual, a truck clutch-

If you are swapping for a later model v8- the best route would be to also swap the transmission as a package. Mating up to the GMC transmissions form a 1961 could be tricky. IIRC, there is a lot of working room in the transmission hump, and the new mountings should be pretty straightforward to weld in.

good luck!

lonesome Polecat · Newbie

If you keep the 261, consider having a timing gauge welded on at the front of the engine, while it is out , as the old style timing through a hole in the flywheel cover is 'special' to say the least. \
consider new manifold with better flow then the originals, ands two linked carburetors. ''the 261 can take a lot of boost.

long stroke · Canadian Poncho Superstar!

lonesome Polecat wrote:
If you keep the 261, consider having a timing gauge welded on at the front of the engine, while it is out , as the old style timing through a hole in the flywheel cover is 'special' to say the least. \
consider new manifold with better flow then the originals, ands two linked carburetors. ''the 261 can take a lot of boost.

What ! confuse

Glenn Musgrave · Addicted!

I am a fan of the 261 but if swapping it out is what you want to do I echo Eric's comment get tranie cross member the whole 9 yds. In fact I would encourage you to try to get the car. I've gone through the swapping process a few times and seemingly simple things like throttle linkage to the gas pedal, pipe or hose to connect to the power brake booster, engine wiring etc. If you have a complete donor car you can strip what you need when you need it and sell the rest. The transmission tail shaft length will likely be different so you may have to go on the hunt for a driveshaft or get one made. Can someone check a parts book to see if the driveshaft for a 6 cyl and an 8 with 300 hp are the same for his car. I'd be concerned adding this kind of extra h.p. and torque could stress and twist the driveshaft. The original shaft wasn't designed for this so I likely wouldn't use the original one even if it did fit. Getting the engine and tranie bolted in place is often the easy part.