Engine Temp

[West Coast Dave]

When making a change from iron heads to aluminum heads has anybody noticed an increased running temp. It seems like we jumped up about 25-30 degrees. Is it normal, if not what might be the problem?? Thanx for the advice.

[Havasu Hangin']

My engine is running about that much warmer, but I also changed the sending unit from the intake to the head...aluminum has better heat transfer? maybe...

[KC]

aluminuim has MUCH better heat transfer over cast iron, so they are going to absorb and disapate the heat farther, faster and hotter.
chances are that you have a temp drop on the block that equates to a temp drop for the oil.
$.02

[502procharger]

kc,
did you order your zz502?
brian

[Hotcrusader76]

KC:
aluminuim has MUCH better heat transfer over cast iron, so they are going to absorb and disapate the heat farther, faster and hotter.
chances are that you have a temp drop on the block that equates to a temp drop for the oil.
$.02Actually its just the opposite. Aluminum has a lower "specific heat capacity" (.900) over Iron (.473), hence the reason Iron heats up faster. Its not that Aluminum gets rid of it faster, its that it never is able to retain the heat as fast as Iron can, and it just doesn't transfer as easy. This is why you can pick up Aluminum foil off a Bar BQ and not get burned. Pick up a cast Iron and skillet and your smoking!
In theory your heads should run cooler than Iron.
:D
[ August 27, 2002, 06:17 AM: Message edited by: Hotcrusader76 ]

[KC]

as I read through one of my big block books last night, it states that aluminum heads should run cooler also.... how does a large heat sink sitting ontop of a motor run cooler??? that heat is going some place, I gues the energy is being kept closer to the chamber and leaving with the exhaust.... not like the heads have fins for cooling. ok, ok...

[KC]

502procharger....
no I did not order the zz502, the Ram Jet version will not fit in my engine bay without a significant air scoop, so I am going to patiently wait for a used 502 MPI... I want the EFI, no carbs for me, almost snagged EFI system on EBay but the seller pulled it three hours before the end of auction.
Given how rare the 502 MPI is, I might just go overboard and get the whipple.
KC

[502procharger]

kc,
try this guy, his name is kevin. it is the place i snaged that 540. i do not know what exactly he has, but there were a ton of new and used engines. he said he would beat anyones best price. give him a shout. 1-732-751-1200. he ships nation wide, and i think like $200.00 is the max shipping he charges(i could be wrong)
let me know what you find out.

[502procharger]

test
[ August 27, 2002, 06:11 PM: Message edited by: 502procharger ]

[KC]

502procharger...
Thanks, I'll call him in the AM. KC

[502procharger]

also look at these 502's
http://www.offshoreonly.com/cgi-bin/classifieds/classifieds.cgi?db=sterndrives&website=&language=&session_key=&search_and_display_db_button=on&results_format=long&db_id=231&query=r etrieval

[Hotcrusader76]

KC:
as I read through one of my big block books last night, it states that aluminum heads should run cooler also.... how does a large heat sink sitting ontop of a motor run cooler??? that heat is going some place, I gues the energy is being kept closer to the chamber and leaving with the exhaust.... not like the heads have fins for cooling. ok, ok...With Aluminum's SPC (Specific Heat capacity) being .900 J/g'C (Joules per gram degrees Celcius) and Iron's being .473 J/g'C, it takes less energy to +gain or -lose temp. from Aluminum than Iron, with heat. So basically it comes and goes faster, meaning it runs cooler than cast Iron. What's the catch? Iron is stronger! wink
DO NOT ask me how I came up with that, because I don't have a clue either. You should talk to me when I am drinking... :D
-Ty
[ August 27, 2002, 08:57 PM: Message edited by: Hotcrusader76 ]

[KC]

502procharger...
I just picked up a 454 MAG MPI with 20 hours on it for a great price, a good bulletproof motor, it needs a fuel system. So I am calling Whipple today to see if their 7.4 MPI 310hp system will sit ontop of the 385hp MAG, I think it will!
That would give me enough power to max out my Bravo on without the wory of destroying the pistons and the rods as with the 7.4 310hp motor.
I'm still on the waiting list for one of those 502s, Thanks.