hey

should have my engine done by mid-august (have to wait for HR lifters). so i figure i'll work on modifying the cooling system since i had overheating problems with my last set-up.

i'm going with a 2 row alum rad and a nice electric fan from a C4. now i need to get a water pump, which i can't seem to make up my mind about...do i get an electric and earn back lost HP and save weight, or go with an aluminum mechanical pump and maintain water pressure?

also, been doing some research over the web and i can't seem to find much info on piping the water flow to the back of the block or tapping into the heads. does anyone have any info or EXPERIENCE (KEY WORD THERE) on the best way to do this without the bubba effect taking over.. i'm running victor jr heads. the vette will be driven on the street occasionally, definitely not a daily driver.

thanks in advance. :chevy

 

You left out some info but I can share my experience and that from the forum on some things. The vast majority of forum members swear by Spal elect fans. The best period! What yr vette has just 2 cores? Is that wha it came with? My 74 had a worn out 3 core and I had it rebuilt to 4 core. I saw that mod on the forum, saved money, better fit than aftermarket. Don't get cheap on waterpump! Low pressure allows steam pockets to form. Steam does not conduct heat away from engine Spend the money, don't scrimp on this. If you are planning to run A/C you will need all the help you can get. All the name WPs seem to work well. The roller rockers made a difference in my car. The RRs were one of the first things I did. Reduced temps and mover the engine's "sweet spot" up 200 rpms. You will also be happy HR when you get lifters. I spoke to honcho of Be Cool. He said" Most guys scrimp on the rad and try to make it up w/huge fans. He stated thart the rad alone w/o fan should carry car at cruising speeds. Getting good rad fit is important. The seals need to be good or else air goes around rad rather than through it. Hope this helps. Lower temps = HP & TQ. 180 to 220 is 20 HP diff.

 

my vette ('75) originally had the 4 core heavy copper. i just recently got a griffin 2 core aluminum-- so right there i should see a big difference in temp.

i had a flex fan on the old engine, this time i'm going with a 17" electric from a C4, so that will save some low rpm drag on the crank.

also on the last engine, i had the stock pump, which i think is where most of my high-temp probs came from. i wanted to go with an electric, but now i'm reading about a mechanincal water pump made by stewart that is iused in winston cup cars. supposedly they outflow edelbrocks best pump (victor series) and use only around 2.5 hp at 4000 rpm. so i think i'll pass on the electric and not on water pressure.

also, no A/C.. took that out a long time ago-- i don't like A/C so that saved me some weight.

 

I use the Edelbrock Victor short water pump which has a cast iron impellor vs. other brands stamped steel impellors. I am using a stock big block rad with the factory clutch fan, and my temps rarely exceed 160 as indicated on my gauge. And that's with the so called "problematic" (hard to cool) 400 small block, with at least 1/3 of the block filled with block filler.

As far as hp lost, I can't say. But the pump must flow pretty good. I don't even recall hearing my clutch fan totally engage! For cooling, I think that the stock clutch fan cannot be beat.

 

I think Moroso sells that water re-routing kit for the small block. Look for the Smokey Yunick book (not sure of the title) He's the one that designed it.
Good luck

 

Ummm...hate to break it to you...copper radiators transfer heat a heck of a lot better than the cheaper aluminum radiators. The 4 row copper radiator was the ONLY way to cool a big block. The aluminum 2 and 3 row radiators just couldn't keep the motors cool.

As for aftermarket aluminum radiators...they are made for pretty much one thing...racing, thats wide open throttle, high speed airflow...and not made for sitting at stoplights with the AC running in 110ş sunny weather. You draw your own conclusion but GM did not get it 'wrong'.

 

yeah, i heard about that smokey yunik book, have to make a run to barnes & noble this weekend.

as far as the copper rads...aluminum dissipates it faster than copper (cooper retains heat longer)..which means cooler water and a cooler engine.

and i am building this engine for racing, not daily driving (and no A/C), which is another advantage of the aluminum rads-- much lighter than coopper.

besides, if copper was better, why did GM switch to aluminum radiators in all their production cars with A/C? :confused: