pharlap

I'm getting ready to replace the A/C blower motor and fan in my 1982 corvette. I've looked at some online and I don't know which one i need to go with. I want to know which blower motor and/or fan i need to get to move the most air. I would love to hear your opinions on the subject and which web sites I can find them at.

FYI - I'm not concerned with keeping the car original. A strong blowing A/C that'll keep me cool this summer is far more Important to me than maintaining the purity of my car. I have no problem with after market products if they're good ones.

Also, I read something, somewhere about putting a C4 fan or motor or fan and motor in a C3, but I didn't understand all the modifications that have to be done to do so. If you've done this before or know how to do it please fill me in as to what I'd have do to make it work. They said the C4 set up would move a lot more air than any of the C3's.


Thanks,

Rotonda

The C4 squirrel cage fan is the same diameter as the C3. The differences are - 1) it is approx. 1/2 inch longer, and 2) it is plastic, has many more vanes than the C3 and the blades are more efficiently contoured than the stamped C3 fan. The C4 will mount onto the C3 motor. To mount it back into the car, you need to fabricate a spacer to accommodate the longer length.

I have a C3 motor (from a 77) with a C4 fan attached that I will sell for $20 + shipping. It was working when I removed it and installed a Vintage Air system. If you want it, send me a PM.

Easy Mike

If your motor is otherwise fine, you do not need a replacement. You want the C4 squirrel cage for better air flow.

fishslayer143

Your stock motor is fine.. Get a C4 Blower wheel { Amazon..4 Seasons Brands ..$20 } ... Fabricate a 1/2 inch spacer on the motor flange mount, and enjoy.. You will get 30-40 % more airflow.. I did mine years ago

CA-Legal-Vette

I had understood that the C4 fan motor was more powerful than that on the C3. Not the case?

doorgunner

Lots of info from a previous thread.................

https://www.corvetteforum.com/forums...r-upgrade.html

CA-Legal-Vette

Interesting read. It almost, but doesn't quite, answer my question. If the one point regarding the RPM is true, then for a motor to turn a larger fan at the same RPM (i.e., moving more air), it must be more powerful. Fair point though that a new motor (C3 or C4) will run better than an old one of either.

fishslayer143

The RPM is the same, if your motor is old,needs replacing anyway, then get a new C4 motor otherwise, if your motor works fine, you just need the wheel...it is not larger in diameter, it is longer in length , is lighter plastic not steel and has more vanes.. It simply moves a lot more air..

pharlap

Thank you all for sharing this info with me. I read the thread that someone attached and it was very interesting. I live in Mississippi and it's hot as hell in the south during the summer time and that's why I want the best set up I can get. I'm going to try this conversion with the C4 fan for sure. I have a couple more questions for you guys

it looks like there's a difference between 1984 to 86 and 87 to 96 on the C4's systems. I'm seeing 87-96 when I looked up C4 blower motors and fans. Is this the C4 blower motor and fan I need to use?

I've got to have a new blower motor too. Should I buy a GM blower motor and use something like a four seasons fan? or will it matter if I just buy a four seasons motor and fan combo?

I also seen that people used 3 different size spacers in the attached thread, 3/4", 1/2" and 3/8" all made of plywood. Has anyone done this with a 1982 and if so which size spacer did you use for the 82?

alconk

Interested as well..

terry82

Its the cage that gives you the better flow.Also check the air ducts.From the factory they were not good ,seal them up.

Spoticus

There is a full size spacer template available from this site. You will have to register to get access to it though.
http://www.vettemod.com/forum/downlo...?do=file&id=51

I made my spacer from a nylon chopping board so it doesnt need painting to make it water proof. I think it was half inch thick when finished. It was made with two layers of the board to get the thickness right.

I have read also that you should also upgrade the earth wire from the blower motor to a larger size to get a little more power from the motor. I have not done this part yet but intend to do it once it gets to the top of the list of things to do on my 78.

Bloodzone

I've had my C4 fan for around 6 months now and not installed it as of yet. The spacer was holding me back. I don't have the tools to fab it myself and the job has always sat on the back burner. I had an idea after reading this thread. I'm gonna use a rear hood seal I have laying around. Cut it to correct length and bind ends together with electric tape. It will become a giant o-ring. I may make 2 and double stack them to get the 3/4" needed.

pharlap

That sounds like it'll work. I'm thinking about trying UMHW plastic to make my spacer. If that don't work, I'll use plywood. Thanks for sharing your idea with me.
Just a thought, but If your spacer design doesn't work out for you, hit me up. I have access to the tools and I think it should be pretty easy to fabricate. I can make a spacer for you, while I'm making mine. the only thing is, it may be a few weeks before I tackle this project.
Thanks

Vette-kid

I like the cutting board idea, i was leaning that way myself. I use a few in the garage as a work surface anyway.

Psychovette

Looks like a great modification! My '79 Vette has a good working blower motor but I'd like to change the blower wheel. I looked at the 4 seasons blower wheels on Amazon but don't know which one to order. They don't say what cars they will fit. Any ideas?? Maybe I should just find a C-4 motor and blower wheel assembly and make the necessary shims. Are the blowers different on earlier and later year C-4's?? Thanks.

kanvasman

The other mod that a lot of people do when changing out the cage is to go with a heavier ground wire to the motor. If your c3 motor is good, you don't need to change it. That seems to be a common issue with the older cars that was redesigned when they built the C4.

Street Rat

I ended up with a 1/2" spacer made from abs. Use something easier to cut and shape. Don't ask me how I know. And yes the bigger ground wire helped quite a bit too.

Frank_Nesta

if you use a C4 Blower motor and cage you still need a bigger ground wire. Adding an extra ground with just a jumper wire with alligator clips as a test i could hear the RPMs go up.

M. Young

I printed the drawing off Vettemod and I'm putting it into CAD. I'm going to make one out of aluminum or nylon on the Bridgeport. IF I decide to make some would anyone want one? 1/2 inch thick? You pay for materials and shipping?

-Michael