My son and I are planning an engine/tranny swap with our 81 V6. Does anyone have any suggestions and or advice on what we are up against? We are planning on swapping out the V6 with 350 crate engine. The transmission we have decided on either 4 or 5 speed. The 5 speed swap may be $ prohibitive. Any insight will be greatly appreciated.

Paul

The swap will not be the hardest thing in the world. You will need a lot of new parts, like the ignition system and exhaust. I don't really know what else to say.

u need smallblock motor mounts 4 speed trannys are easy to come by and u need the clutch linkage and pedals to do the converstion also a bigger radiator there is alot of info here just keep posting questions as u go and we will help:bowtie:

We are planning on swapping out the V6 with 350 crate engine. The transmission we have decided on either 4 or 5 speed. The

It sounds like a cool project. I say +1 to a basic GM performance crate engine and a rebuilt 4 speed. Add a nice exhaust and a reliable carb & you will have a great learning experience for your son.

The '81 was computer controlled, so I would suggest looking for the wiring harness from a 78 to 80 V8 to make your life a little easier.

P.S. The instruments are different for the 6 & 8 cylinders (tach).

Thanks for the info. My son is in the automotive program here in Virginia Beach but I know there are things that he's not going to think of. I knew the 81 was computer controlled, nice to know about the wiring harness and I figured the radiator would have to go. He's already got the carb, intake and exhaust picked out. Couple more questions.

How about the ignition? Anything we can use from the V6? And, do the engine mounts mount in the same place as the V6 one does? I have buds that weld, just want to know what I need to plan for.

We have a lot of stuff to do to the car, I just want some info on things we need to do before we drop the engine in. (buy it for one) Still farting with the brakes. I think the rubber part of the brake lines are shot.

Thanks again for all your help. This is a great site.

The subframe is drilled with the holes for all stock engines, so a big block, small block, Pontiac, I-6, Chevy V-6, or Buick V-6 will all bolt in with the proper mounts. It makes things easy, as long as you know what holes to use. Somebody here has posted the info somewhere.
Everything should be bolt in, but some parts will need to be changed. For instance, you may need to change the upper radiator support when you change the radiator, if the radiator is wider.
For ignition, you should have a 6 cylinder HEI in there. That won't work for you. All you need to do is install a Chavy V-8 HEI. The power wire will connect right up, so that is really simple.
You may want to change the springs and shocks, as they are probably worn and the extra weight won't help, but that is not a high priority type of thing. He might like the stance, and the shocks might not be worn that much.

Some of the items you will need to address have been mentioned. The motor mounts for a V6 and a V8 may be the same, I am not sure, but if not or if the V6 mounts are OE, it is about time to replace them.

You will need a new water pump and assorted belts, brackets and pulleys to mount the alternator, power steering pump and ac compressor. A trip through the junkyard should yield a similar setup on another car and getting all items from an intact front of the motor will make things much easier.

You will need to get an exhaust system made up. If you are using cast iron manifolds or shortie headers, a stock 81 Z exhaust from any local parts house will bolt right up. If you want to do away with the cat, you can use a true dual system from early 70’s Z cars with a little tweaking. If you use long tube headers, you can again use the stock exhaust system from early 70’s Z Camaros, an aftermarket kit from someone like Flowmaster, or have your local muffler shop make up something custom.

For the trans, if the car is now a manual, you are almost there. You will need the appropriate clutch and shifter for whatever trans you choose. The trans crossmember will likely fit with maybe a little repositioning. The drive shaft length and front yoke may or may not have to be addressed, depending on what trans is in the car now and what you go to with the 350. If the car is currently auto, there will be some additional work needed to add the clutch linkage, and whatever else is necessary. I have gone from manual to auto, but never the other way around. Good luck.

Thanks Warped:
That helps alot, the car currently is auto, we are going to get some type of headers, probably long tube since we aren't putting cats on it. If a car is registered antique in VA, No inspection is required. Im trying to talk the boy into shortie headers and exhaust off a z28. If not, it will be fun driving to a muffler shop with open headers. Doesnt the water pump usually come with a long block crate engine? Also, whoever had the car before, already took out the a/c, so its gonna stay off. It'll be fun putting it in, hopefully by the end of the summer. By then we should have the freaking brakes working like they should and have a new radiator, and the rearend upgraded. (Gotta have power to both wheels)

As a side note, are body mounts hard to replace and should we try to get that done before the new engine is in? We are already planning to put a new front end kit on.

Thanks again for the info.

http://www.alangrovecomponents.com/ - makes some nice fitting inexpensive brackets for mounting alternator and PS pump - or you could just grap some brackets out of a junk yard.

For a manual trans car the 27.5 x 19 Griffon radiator from summit can be made to fit with some modifications. MORE than enough cooling for a mild 350, and for a few bucks more than a stocker you get aluminum. Could be used for auto trans too, but you would have to use a seperate trans cooler.

Good luck with the project. Sounds like fun!

The last engine I bought did not come with a water pump. I would imagine that it will depend on whose engine and what they normally come with.

I did the subframe mounts on my car last fall, and it was not particularly difficult. I used the Energy Suspension poly mounts and the kit came with everything needed. My best advice would be to use a good rust penetrant (I used PB Blaster, stock item at my local NAPA), and spray the heck out of the bolt and nut. I did it every day or 2 for about 3 weeks before I attempted to break the bolts loose. The 2 rear bushings were easy, just about falling apart once the bolts were out, but the fronts (under the core support) required a little persuasion to remove. I can give more specifics if you need, but there are a number of good posts about this in the brakes, steering and suspension forum.

on the 81 u will need a regular engine harness cause the computer harness is seprate and will not effect anything if u remove it

I would scrap all the wiring, except for lights and turn signals, forward of the firewall and start fresh. My 81 plagued me with electrical issues for years until I took it all out.

^^ plus it doesn't look to good. Trust me, I keep saying "I'm removing all the wiring I don't need come this spring" every time I pop the hood.

It's really a straight forward affair. Change the frame mounts and get some engine mounts if you don't have those, new radiator and possibly upper core support (as said before) - as cheap and easy as finding the right junk yard, ignition, exhaust ("Dynomax Blackjack" 1 5/8", 3" collector are roughly $80 from advanced auto). For the pulleys & brackets, you could get those out of a junk yard as well.
I don't know about the power steering pump, but if you get the bracket for it from a junk yard, it's not that much to buy a new one from the parts store.
Sounds like your clutch and linkage problems have already been addressed by Thomas81Z.
If you can't find where you need to put the engine frame mounts on the site, one of the easiest ways to find out is to go to your local GM dealership and tell them you need a diagram on where they go for a sbc. That's what I did when I swapped a 79 olds 350 into my 86 cutlass (previously had a 3.8) in my auto tech class my senior year.
Hope you and your son have lots a fun doing this, I wish I could've done something like this with my dad!
Let us know what else you need as you go, and we'll be more than happy to chime in for ya!


-Nate

I've been there. The wiring for the computer will separate from the main harness, no new harness needed. The accessories on the front of the 229 chevy V6 are the same as the sbc, they will bolt up, even the water pump.
The motor mounts will need changed and it is a pita to do.
You will also need a new y-pipe and exhaust manifolds if you plan to retain the stock exhaust. If you have a TH350 trans which you probably have the little th200 or th250? the crossmember will work with the th350 at least. The flexplate and tranny will also bolt to the 350. The hard work is the motor mounts, and fishing the computer harness out of the main harness.

The hard work is the motor mounts,

Exactamundo. After that, it should be cake.