I am new to this forum but not to tech forums in general. I have an 87 Firebird Formula. It has a 305 with a rochester 4 barrel with TPS and Fuel Mixture solnoid. I purchased a 350 GM Goodwrench motor with 35,000 miles on it. It is also carbed. It came out of an 82 Blazer. I need to know without spending countless hours searching through the archives if it is a simple swap. From what I understand, everything should bolt right up. Tranny, engine mounts, exshaust manifolds etc. Please set me straight ASAP! This car needs to be back on the road NOW!!!!I plan to attempt the swap this week. Also, is the oil pan from the 305 the same as the 350?

 

yes to all your questions

 

if i wanted a 350, would i be able to get a small block 350 from and car/truck/van, and still say yes to all of his above questions? does year matter?

 

any 350 will bolt right up to your tranny. All small blocks have the same bellhousing pattern. Your tranny would even bolt up to a big block they are all the same.

Some 4x4 trucks may have a different oil pan but im not positive. I very well could be wrong there. But the motor will bolt right up. Motor mounts, tranny, EVERYTHING will bolt up fine dont worry.

 

gm is awesome! can someone confirm the quoted post?

 

Confirmed,He is correct.Why do you think small/big block chevys are so popular,Besides parts being priced pretty reasonable, more parts interchange than any other make out there.

 

You can buy a 3rd gen with a 305 and swap in a 350 with no modifications. May have to add a few high po parts just for fun

You go buy a 87 mustang with a 302 and decide you want to swap in a 351...have fun. You have to buy special kits to make it fit.

With a chevy anything from a 265 (sweet no oil filter!) to a 400 small block will bolt right in place of the other.

 

'87 305 has one-piece rear main seal, GM Goodwrench 350 has two-piece rear main seal. The flex plates are different, and if the Blazer has 168-tooth flex plate (which it probably does), it won't work. You need a flex plate for '82-'85 F-body automatic application.

The oil pans are different for the same reason. As long as the 350 has the Goodwrench oil pan on it, it will fit in the F-body chassis.

The intake mount bolts are at a different angle for the center two bolts on each side of the intake. The Goodwrench engine doesn't come with an intake. As long as you're happy with the '82 Blazer intake (should have EGR, but may be cast iron instead of aluminum), and it's a 4-bbl intake, no problem. You'll have to switch over the '87 EGR parts to the 350. And carb. And distributor. And thermostat housing. And all temp/vacuum sensors.

The '87 305 carb'd exhaust chokes a 305. It'll be even worse with a 350. But, it will bolt up.

 

Thanks for the fast replies fella's. I tore the bottom end out this past weekend. Before you ask, here's the deal on the motor. My 305 is knocking worse than the prom queen with the football team. Neighbors hate it when I have to be at work at 3:00 am. Well I am a part time Mechanic for a shop near my house so I asked around for a cheap motor and found a guy with a GM Goodwrench crate motor for sale. Has 40,000 or so miles on it with a bad rod knock. the guy hit something in the road and put a hole in the pan
motor is complete minus the carb and the distributor. He gave it to me for $150. It is now in my posession on my engine stand. Like I was saying, I took the crank out and OOOUUUCCCHHHH!!!!!! Wiped out #'s 8,7,6,5 rod bearings. Bye Bye crank! I have the crank back in as of today, 40 over on the mains and 20 over on the rods. Damn she is beautiful and shinny.
I have just a few more questions. on this subject of the 350 swap.

Will the 350 Exhaust manifolds mount directly to the existing down pipes?

Should I use the flywheel from the 305?

Will there be any problems with the Quadra-jet from my 305 working on the 350? It is a 4 barrel with the fuel mixture solnoid and TPS. Brand spanking New! Well Basically. It was completely rebuilt including the metering rods.

Now for the big question, What size cam can I put in for a little bit more umph!!? Would like something with a good idle and lots of power between 2500-6000 Rpms. Any suggestions?