pappy92651

Hello Dave,

Thanks for the link. I can use that.

FWIW one fan on the 32V engine cooling system does not quite do it. I tried this once before on my 89 and the water temp got above 230F with a 70F ambient. For better or worse 32V guys are stuck with a dual fan system. The close environment and HP create big cooling issues once you get above 400 crank HP (also toss in a heat source called the automatic transmission).

SharkSkin

Yes, the dual fans only move a bit more air when they're both running, but over a greater area. I could see where that would be a benefit. Unless/until I have some reason to do away with the mechanical fan, this was the simplest solution for my needs. Specs for the smaller fans like you want are available too, just poke around there a bit.

Tony

A thought...If you want help running cooler, get your self an external oil cooler and dont bother with the one in the radiator end tank.

blau928

Steve,

Tony's right.. Just plumb in an external cooler with a thermostat switch for the trans... Or, just run lines from the factory aux trans cooler for the auto's... Motorsport has an interesting setup that uses a dual fan shroud that will move close to 5000 CFM... Devek has an interesting one as well..

I will be replacing my factory aux cooler with a larger Setrab unit for this exact reason...!

HTH,

rob rossitto

http://www.jaycorptech.com/showproduct.aspx?productid=15&categoryid=2 has the new 11" stuff that draws only 18amps/1390cfm for $125 or so each... don't get bagged on one of those 100+ test runs or it won't be wearing out your fans you'll worry about on the bus to the "college" showers

aux coolers work too, had dual tranny rads on my 440mopar motorhome pulling a 23' toybox in the desert 110f, no prob on engine/trans temps... might help more if engine rad was replumbed to use extra space from unused oil/trans cooling stuff too, but I thought I'd read someplace it's done that way to keep consistent component temps/avoid thermal shock/etc (at least for engine oil coolers)... on my 'kid' project (289 powered pinto), I had to cut holes in the fenderwells everywhere I could to ventalate that V8 in a shoebox... finally determined it was destined to being a saturday night special/afraid of the sun like a vampire... something about the limited space to dissapate heat...

like you said, in 100f ambient, not much you can do... good news is everybody else is handicapped the same - unless you've got those mongo 5000cfm fans! sounds like you could create global cooling, but maybe need an aux gen to keep'em running and the front end of a peterbuilt to mount'em?

blau928

Er Rob,

You could have your stock alternator rewired to produce 130+ amps like the mustang guys do to their alternators.. a few hundred bucks and a warranty....

the thermostat should take care of the aux cooler circuit's thermal shock.... mocal has one for a few $ that you could plumb in the lines no problemo.... Same for the oil cooler...

You could use a cooler rated for the additional heat load and cross reference the BTU heat rejection performance in 100F ambient... This way, when you hit the 100F, you will be cool...

Maybe that's too much charting or research...?

Anyway.... .02,

rob rossitto

yep, got mine tested at 140amps, think it'll be fine for the spal stuff anyway... charts/research? it makes my head hurt - just wake me & give me the part #'s when it's done (lol)... think most strokers seem to be fine w/the devek rad and the spal setup, so I'd only be making work/mistakes if I tried to re-invent the architecture and had to go through all the testing/doubt I'd ever improve what everyone else has done... w/you mr blau - a stroked & blown monster is a brave new world, not a lot of footsteps to follow except for a track car or two/maybe tim murphy pretty soon... glad you like charts and research (lol)...

but always looking for ways to help the air intake - as steve noted it does get heat soaked at idle on a hot day... think steves/louis/mark k's ideas/research have uncovered a few things we can do to help on that front, and what doesn't work too...

however as steve noted, I suspect if the ambient temp is 100f, since the density altitude or availible air is like running at 9 or 10 thousand feet msl, w/the 3% per 1k drop in performance, cool radiator or not - unless we're cooling the intake air at or below ambient (a la intercooler/magic tubes/diverters/whatever), we're going to suffer a bit, even if our engine temps are optimal... also there's that drop in box pressure under low speed/no speed that'd be nice to cure/minimize/maybe w/different boxes, ducting, etc... IMO, those are the little buggers in the punch bowl we might be able to cure/minimize... like everything else on these mean machines, improving on dr p's research/designs is not a simple task, as they seemed to like charts & math too - and IMO, did a pretty good job (except for not putting cup holders in the right places/not making more 928's)...

blau928

Sometimes a little chart reading can do a lot of good.... Now, I'm no scientist, but sometimes torture myself by performing mental calculations with mathematical tools....!

Me just man from 3rd world liking my little shark and driving it as much as I can..! Ya Mon..!


Yes, but with the added capacity of a larger cooling system being able to absorb and reject more heat, will allow the water to be cooler = motor runs cooler... Now, you can add some more fuel and get some more oomph.. 100F air is not that hot... The SC cars are positive pressure post IC at higher numbers......


cool water and warm oil make power.. Them fellas in NASCAR got 800+ HP runnin in hot weatha in tha south alla time...

Granted the humidity will affect the density ratio of the air positively in tha south... When they run at Sonoma though, they get lotsa dry hot 100F non humid days and still get 800+hp.....

I lost all them part numbers...! I just have some boxes in my barn with "stuff" in them..

mike10562004

bump this is good stuff

callgeorge

Quick story: last year one of my fuses blew so as a default I believe at least one fan was running all the time with engine temps around 170 degrees. I replaced this bad fuse with 180 plus degree engine temps as a result. I am thinking about removing this fuse with added benefit of cooler temps. Any thoughts?

mark kibort

a lot of bad bad stuff in this thread. "1psi", .1sec gains 0-60mph, etc.

there are 3 factors here. pressure in the nose area, flow losses going over the radiator, and heat transfer into the intake runners from the air touching the top of the radiator.

fact: air pressure at the nose is around .11psi, NOT 1psi, at near 100mph (as a note, it goes to about .4psi at 160mph with no losses)
fact: the transient time for 250cfm, per tube over a 180 degree radiator is negligible. more heat is transfered down the engine compartment path, before the air box.
fact: disrupting flow to go around the sharp corner of the insulator plate, would probably negate any heat transfer gains

any gains remotely possible, would be well beyond human perception.

mk