how much power does that hot rod have? it seems that today manf r suggesting that anything over 600 hp might have a problem running an electric water pump on the street..i had problems in the past with 1, but today i have lot more fan (electric 1300 cfm x 2). and 26" aluminum radiator,. i have close to 700 hp. locked timing, seems to run a little hotter with the timing that way...would be great to get rid of the metal fan but, 300$ and the wiring is a gamble. it barely keeps up now depending on the temps.
it's something in the neighborhood of 590-600 hp @ 6100-6200rpm-ish,
at it's current state, pulls hard up that point
(
probably not making that above 5800-5900 right now, HP restrictive man.'s)
just a lowly street-strip drag-car, in search of a corner,
driver/car not dedicated racecar
(
I've had a few of these types of stroker builds, this a tad milder than my old combo was,
mainly this one less converter & less camshaft &/or compression, is still 11:1 zero deck flatops)
it's a little more hp with the step headers, like about 7%-10%
or more @ the RW
(
I'm gonna' build a new set, long story, the headers I had wouldn't fit with the rack & pinion)
I had to put the hand ported HP manifolds & 3" head-pipes back on for a while
it's really choked down with the Iron HP manifold, runs at about 195*
in 100* Calif. summer here at altitude
with the step headers it was running cooler, at like 180*-185* pretty regularly
& the fans I used are
3000cfm puller w/shroud &
2900cfm pusher,
I didn't skimp on cfm, IMO it has plenty of cfm flow
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I run 18* initial timing & 18* of added advance, with an FOB 18* advance plate
for 36* total all in @ about 3000rpm & the softest adv. curve springs
(springs form Mr. Gasket or Moroso ?)
& it has an adj. vacuum advance, MP dist. from like 2007-ish
it's not ideal for an all-out racecar (750+hp) maybe, but works for my set up
& what I do with it, I'm sure I'd do pretty well at the track if it was set up for it too
(
it's set up to actually handle & drive, big front & rear sway bars etc. & not just 1/4 mile blasts)
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as to the use of the 35gpm electric water pump
35gpm is plenty too (at my hp level anyway) I actually had to restrict some of the flow
(5/8" - 3/4" opening) so the water would stay in the radiator a tad bit longer
In my case a 55gpm or more volume/flow, I'd have had to restrict it even more
sort of defeats the purpose of more flow/volume
I've ran it like this now since 2007
with a 100 more HP, I may have decided or gone to a 55gpm pump
but it didn't need it "yet"
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If I had chose to use a wider 26" 'HD' style radiator
(my car never had)
I'd have to cut out & mod. the org. opening in the core-support
& different mounts for the radiator
to get the benefit of the extra 4" of flow & use a 26" radiator
I didn't cut anything on the car, it was a
bolt in with the 22" MRE custom rad.
or almost any other aftermarket 22" lager tube alum rad.
(
I had the 26" HD rad. in my 68 Charger, with a similar RB stroker 513cid build
mech. pump & fan & it didn't cool as well as what I have now, by any means)
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I currently have no issues of overheating, whatsoever "yet"
even "putzing" around at near idle a lot
I do a bunch of test blast all the time, full throttle for 8-10 seconds or more
(or as long as I can on the roads here), it cools down rather quickly
it really doesn't spike much even, maybe 10* - 15* total (205* maybe)
albeit with the
heat sink/Iron HP manifolds vs the headers,
it takes
a bit longer to come back down to normal temp.s,
hopefully to cure that very soon, with the new custom home built headers
& scavenger 4-2-1 collectors, I will do
sooner or later 
...
