5m-ge future engine mods?

d557charger · 10-09-2011, 02:53 AM

Hi,
I used to work as a tech at a Dodge dealership (haha, I agree - except for Dodges from right now and the ones from '64-'72).
Anyway, a tuning situation once came up and we were all divided about the fan issue. In my own research I found many many articles on the internet showing that an electric fan will nearly rob as much power as a clutch type mechanical one. Think about it, there's no such thing as free power, so to spin that fan, the alternator has to be robbing more hp to feed more electricity to the fan motor. Even if no power were lost going from mechanical => electric => mechanical power again the amount of power needed to spin a fan should remain the same. You may gain a few hp, like one or two (and that only well below the power band for the 5M), and it might improve your mph some... but I personally don't think it's worth the time, effort & jury rigging.

Either way though, no fan of either type can push as much air over the engine as traveling even at 15 ~20 mph can do, and electric fans cut out before that speed, and mechanical fans have clutches that slip out before 3,000 rpm (meaning a mechanical fan cannot steal hp when your engine is running over 3,000 rpm, unless the clutch is stuck), so it's kind of half dozen one way, half dozen the other ... IMHO

Anyway, this is my first post - I'm hoping to get a like new '85 Celica Supra in the coming weeks! It's been a while since I had a sports car so seeing the tuning ideas are welcome!

10-09-2011, 02:53 AM	#13
d557charger Stock Join Date: Oct 2011 Location: Oakdale, Pa Posts: 2	Electric vs Mechanical Fans Hi, I used to work as a tech at a Dodge dealership (haha, I agree - except for Dodges from right now and the ones from '64-'72). Anyway, a tuning situation once came up and we were all divided about the fan issue. In my own research I found many many articles on the internet showing that an electric fan will nearly rob as much power as a clutch type mechanical one. Think about it, there's no such thing as free power, so to spin that fan, the alternator has to be robbing more hp to feed more electricity to the fan motor. Even if no power were lost going from mechanical => electric => mechanical power again the amount of power needed to spin a fan should remain the same. You may gain a few hp, like one or two (and that only well below the power band for the 5M), and it might improve your mph some... but I personally don't think it's worth the time, effort & jury rigging. Either way though, no fan of either type can push as much air over the engine as traveling even at 15 ~20 mph can do, and electric fans cut out before that speed, and mechanical fans have clutches that slip out before 3,000 rpm (meaning a mechanical fan cannot steal hp when your engine is running over 3,000 rpm, unless the clutch is stuck), so it's kind of half dozen one way, half dozen the other ... IMHO Anyway, this is my first post - I'm hoping to get a like new '85 Celica Supra in the coming weeks! It's been a while since I had a sports car so seeing the tuning ideas are welcome!