I will be looking in to getting a more hp engine an every one tells you to go big....well my 84 is a g-body so ?I would like to get the Buick Grand National 3.8 an was wondering, might this be to much for my first swap?

 

Swapping in a turbo motor would be fun and a challenge.
An easier swap is a 403 Olds. I swapped a 403 out of a 1979 Trans Am into a Cadillac that originally had a 307. Talk about sleeper!
Everything bolted right up and looks stock.
It's also a lot cheaper finding a good running 403 than it is to get a complete Turbo motor. Not to mention the nightmare of figuring out the wiring and computer for the Sequential fuel injection.

If you had a complete Grand National donor car to swap everything from that would be an option...where do you find a wrecked GN with a good engine??

 

That's kind of backwards. Go bigger. The 3.8 didn't have that much power. You could only run about 18 psi of boost at most. A nice 350 or 403 would be better.

 

I would go with a 350 or 403 as well. It would cost quite a bit more to build a 3.8L turbo engine.

 

Since the GN is also a G-body, just get the appropriate Buick motor and frame mounts. Of course, you'll need all the brackets, etc. The biggest problem will be the computer and wiring, of course. This swap has been done before.

 

thank you guys,Looks like i have to look at this a bit more be for moving on.

 

Just keep in mind that the GN guys that have 500 to 600 HP have a lot of money invested in that motor, a lot.

Turbos are fun thou

 

yea very true but you do start off witha lot more then 180hp {:

 

How about slap a turbo on a 403? Or better yet, turbo a 455.

 

Before you toss out that 307 take a look at this article from the EMC that put out 435 HP.
http://www.popularhotrodding.com/tec...ine/index.html
That's better than a stock 455. Right now there is a guy campaigning a 307 in stock eliminator class running in the 10's. My vote for you would be a stroker 350 Olds. Much stronger block than the 403.

 

How much time (money) do you think that guy put in, just for the heads?

 

The heads were cast iron 5a from a mid 80s Toro. Core motor was probably $100. I scrapped three last year. As far as time goes he spray welded the exhaust dividers & epoxied the floor on the intake side. He didn't hog the sh*t out of them. Flow numbers were kind of low. If I had to guess maybe 25-30 hours of port time and probably less than ten into fitment of the valvetrain including back cutting the valves. With the honeycomb Comp springs, titanium keepers, shaft rockers, Chevy 2.02 valves - less than $1000 total. He actually used 1.65 rockers on the exhaust & 1.8 ratio on the intake. He also went with a solid lifter cam instead of roller the setup.

 

How about swapping a 260 for a 350 rocket ?
Going to do it this week. Any advice ?

 

This is about the easiest swap there is. Totally bolt-in. Use the motor mounts and accessory brackets from the 260. Verify that the water pump length on the 350 matches that on the old motor, or just use the 260 pump.

 

Great ! Do you agree it will be more powerful to go from the 260 to 350? The carb is a 2 barrel. Change it ?

 

It would be difficult to make it LESS powerful...

First, you cannot use the intake from the 260 on a 350. The 260 ports are different. Either use the intake that comes with the 350 or get a used or aftermarket one. The 2bbl vs 4bbl question is up to you. If you are doing this for more power, go with a 4bbl. If you want economy, use a 2bbl - although the tiny primary barrels of the Quadrajet will provide very good mileage.

...IF you keep your foot out of the secondaries!

 

Can an Oldsmobile Quad 4 be swapped in for the 260? Would this be an improvement or a downgrade? I know the 260 was pretty anemic.

 

Funny you should mention this, because I've been having similar thoughts, especially since I now have a running Q4. The Q4 was never used in longitudinal installation (Aerotech excepted, of course) but several aftermarket vendors sell parts to install the Q4 in street rods in longitudinal drivelines. Naturally, a trans adapter is required and custom motor mounts must be fabricated. An aftermarket computer is required to drive the EFI and ignition (though I've seen one street rod with a distributor driven off the back of the LH cam, in place of the power steering pump).

Considering that the 260 produced a pavement-ripping 105 HP (that's for the gasoline version, NOT the diesel ), the Q4, even in it's 150 HP base version, sounds pretty good. Add the cams and PROM from a W-40 or W-41 version and even a 307 pales in comparison. Of course, there's a big difference in the shape of the power curves. Don't expect the Q4 to do much of anything below 3,000 RPM.

 

 

Can I take the hei distributor from the 260 and put in the rocket that has points ?

 

Can I use the 260's hei distributor for the 350 that has points

 

Yes.

 

Thanks!!

 

There has been a little surprise. Can the push rods and valve springs from the 260 be used on the 350 ? A bit of rust found on the one side ?

 

The pushrods should be interchangeable, but match them up to be sure. Valve springs depend on the heads. Some Olds heads have deep spring seat pockets. Also, valve spring force is likely different.

 

Ok thanks.

 

Next question : I need the head sequence and torque specs for the the 350 rocket 68 thru 70 casting and intake manifold torque specs and sequence ? Found a mess in the block ! had to tear it down and start all over !!