Radical Rotary Avantgard

Did a search already and came empty handed.
Anyone has changed the 4 fins fan to the 5 fins and noticed any difference in cooling ability??? Fluidyne rad done but traffic does not care about that.
I don't have a problem but summers in TX are not my cup of tea in the RX7 and A/C on a 100 plus degree day.
Thanks for any input.

Mahjik

iTrader: (1)

There was a dicussion about this (way back when):

https://www.rx7club.com/forum/showth...hreadid=101948

jramosrx7

Don't know what the thread says, but don't think you want to do this. I recall a thread here or another place that pointed out that harmonic disssonance is created when 2 five-blade fans are used. It's either the noise or imbalance created.

the_glass_man

iTrader: (2)

Its done for the noise.

Trexthe3rd

I did the mod and there is absolutely no harmonic noise issue. But contrary to what you may believe, the 4 blade pulls a lot more air than the 5 blade, due to the pitch and depth of the blade. Try it for you self, put your hand in front of the fans when they are on and you should be able to tell very clearly which fan pulls more air.

rotorbrain

trexthe3rd is right. the 4 bladed fan pulls more. there is no noise difference. . . especially if you have a loud exhaust. haha.

paul

Astro

has anyone had sucess with som FAL fans or anything aftermarket ?

duboisr

Garfinkle has changed the fan and I have not heard the thumping sound. The fans do sound like they are moving more air , big difference in sound and feel . the cars temps were good before and after. He thinks it has $34 well spent.

7racer

But does anyone have absolute numbers on temps with the fours vs. the fives???

Tanabe

where can i find some aftermarket fans for let's say... a fluidyne radiator? i remember on that a "certain" site that's not up anymore that sold some for $250 and were like less than an inch thick (i think) is that good/worth it? of course i can't get it from "that" site anymore but who else has some that are worth getting?
thanks mike

Radical Rotary Avantgard

If you go to the Fluidyne web site they have fans and you can get the part # to order it from a distributor. Permacool also have on their site different sizes of fan and it gives the specs (size, depth, electrical consumption, CFM's......etc).
I think Summit distributes both so give them a call.

Trexthe3rd

Unless things have changed in the last 6 months, after a lot of research and experimenting (tried other fans and motors). The long and short of it is this, I have not seen any fan or motor with higher output than the oem components. I was quite shocked and amazed. But if you look at the way the car is put together it wouldn't be hard to understand. Just look at the stock coil output, untill this day, I have not seen any aftermarket (so called high output) coils surpass or even meet the oem output.

Trexthe3rd

The result of the mod was a 7-10 deg F temp drop in stand still traffic (the difference is due to the ambient temperatures).

Tanabe

with that said... the best bang for the buck would be the $34 upgrade for dual 4 blade oem fans right?

7racer

Well, maybe not...

I just saw this on Rob Robinette's old site...it basically states the modifications that Mazda did for the 99 spec

The front-end's opening areas have also been increased by factors of 2.1 for the radiator opening, 1.8 for the intercooler duct, 1.8 for the oil cooler, and 1.6 for the front brake cooling duct intake over the previous RX-7. The radiator's core depth has been increased to 27 mm (1.1 in.) from the previous one's 25 mm (1 in.). The 209 kW (280 bhp) engine had its fin-pitch changed from 1.1 mm (0.04 in.) to 1.3 mm (0.05 in.). Twin cooling fans' blades have also been increased, one from five to seven blades and the other four to five blades, while the high-speed electric motors' consumption has been changed from 160W to 120W.

I wonder if these fans are available??