Engine replacement
Thread Starter
Heel & Toe
Joined: Apr 2000
Posts: 23
Likes: 0
From: Auburn, NY USA
Engine replacement
So I’m back. Haven’t posted since about 1997…. Finally decided to do some upgrades to my 81. Over the years I’ve done the interior, suspension, bushings etc. Finally doing some engine work. I had a known long time engine builder build me a 350 four bolt, with 400 heads and a mild cam. He thinks it will be about 350 to 400 hp which is perfect. Time to pull the old smog motor out. Do any of you have any experience in this? I want to put a whole serpentine system on it but I am wondering if it will fit under the hood. I’m also worried about the intake and the 650 carb he put on it and if the hood will close. Just curious before I tear this apart. Current smog motor runs great and all the smog stuff is gone but my 3500 ram truck will still smoke this car easily. I’m torn between leaving this car alone and putting the new engine in something else some day. Have to do something with the new one….. already have a LOT of money invested and more to go. Any thoughts? Much appreciated.
Drifting
Joined: Mar 2008
Posts: 1,806
Likes: 433
From: Denver CO
Pro
Joined: Jun 2021
Posts: 505
Likes: 230
Adding some stall with the torque converter will help with the tall gears. I would think 2200-2400 range depending on the cam specs. You’re pretty limited on serpentine options, but there are threads here on what will fit. I opted to go with a 700r4 when I swapped engines because the swap cost wasn’t much more than the rebuild cost.
Dr. Detroit
Joined: Mar 2012
Posts: 10,095
Likes: 4,022
From: New Braunfels Texas
You need torque to pull that gear and that means 383 or 406......I wouldn't even bother building another 350......especially with 400 heads which were marginal at best......and unless those heads are ported, you will never see 400hp......odd choice of head to spec, unless the guy just had them laying around.
If your engine is sound......modify it. Put some real heads and exhaust on it......
Nobody can tell you if the intake will clear because you didn't tell us what it is. The "650" carb has nothing to do with it......
Need more info...
I built a 385ci for a friend in an 81' and it is a beast with 700r4 trans......rear gear is stock.
Jebby
If your engine is sound......modify it. Put some real heads and exhaust on it......
Nobody can tell you if the intake will clear because you didn't tell us what it is. The "650" carb has nothing to do with it......
Need more info...
I built a 385ci for a friend in an 81' and it is a beast with 700r4 trans......rear gear is stock.
Jebby
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Race Director
Joined: Mar 2017
Posts: 11,906
Likes: 4,479
From: Virginia
Welcome back to the Forum! Everyone seems quick to tell you what you should have done. Why not just swap the engine and see what else needs to be done? It's really easy to spend money on more parts. Spend money on gas, tires, and cheeseburgers instead!
A $700- gantry crane from Harbor Freight might be a safer way to pull the engine, and cheaper than hiring a mechanic.
Please post some photos of the completed engine, unless I read tour post incorrectly. If there's still time to kibbitz, buckle up.
A $700- gantry crane from Harbor Freight might be a safer way to pull the engine, and cheaper than hiring a mechanic.
Please post some photos of the completed engine, unless I read tour post incorrectly. If there's still time to kibbitz, buckle up.