Severe Duty Fan Clutch

Why not go with 2 electric pulling fans.

 

^^^Instead of 2 electric fans...the route I went was a HD fan clutch and 7 blade metal fan...with a shroud of course. I added a 16inch puller fan on the engine side of the radiator. The profile is small enough to not interfere with the mechanical fan. Have it wired through a relay and toggle switch. It's there if I need it, but never have. The mechanical fan pulls a pretty good draw through my old school 4 row brass radiator. I also use an Edelbrock water pump and Robert Shaw high flow stat.

 

I put a severe duty fan clutch on my '93 Suburban 5.7 that I used to tow my race car with. It was very loud, I almost felt like 5 ton truck at times due to the fan clutch roar ! Never had over heating problems after that.

 

I have locked the two together with straps similar to this john deer kit. https://www.greenpartstore.com/John-Deere-Viscous-Fan-Drive-Lock-up-Kit-RE36368.html
Home made of course.

 

I like to use a fan clutch from something like a 78 Chevy truck with a 454. Never an issue.

IMO, clutch fans cool better than electric fans. Much better actually. I’ve converted ever old Camaro I’ve ever owned to clutch fans and cooling issues stopped.

 

I use a hayden 2747 clutch fan and it cools really great in my 65 gto with 455 engine. No more electric fan needed !

 

You don’t need a severe duty fan clutch. What you need is a good radiator flushing, make sure nothing is blocking air flow to rad, you didn’t remove anything that guided air to the rad, and make sure you’re running a shroud. The factory cooling systems on these cars is bulletproof. They torture test them in Death Valley and the Mesa, AZ proving grounds in the summer when designing them. 79 Camaro Is it still have the stock rad and has it ever been flushed?

 

So are strictly wanting a belt driven fan? Honestly a bit of handy work and an electric fan for a 91 Cavalier 2.2 kept my 402 BBC Monte Carlo cool as a cucumber.
I used the GM oval relays , used to scavenge stripped cars for relays and harness connectors at JY, they would sell me basically battery box full of relays, harness and relay brackets for $10-$20. Side cuts can be your friend.
Those oval relays can handle 70am surge with no issues, all water proof and all you need is fan sensor that screws into head for 80s sbc Camaro/Corvette and I believe many aftermarket sources have them in different turn on temps. I ran 10ga fused wire to fan relay the relay to fan motor then grind fan at rad support. I could pull that 402 down perfectly on simple 3 row rad also. And it was not low compression. 10.5 to 1, Chet Herbert Roller cam 800dp Holley 3" duals.

 

I take it that you are keeping it original but I made the switch to an electric fan and it runs 190 weather it's the winter or the dead of summer. I got tired of it running hot sitting in the summer traffic and you can still put a fan with blades to make it look original. Bu

 

I have run a high efficiency waterpump (flowkooler plate) 160 thermostat, and stainless steel flex fan for more than 30 years with a three core radiator, the only time I've had any issues with cooling is when driving highway speeds higher than 70MPH, then it creeps up to around 180. Cools down quickly when the coolant is pushed through the radiator at a slower rate. That was an iron head 377 with a Comp 305Magnum Cam, currently upgrading from that format.