that's exactly right. adding the two up(reduced pump rpm at low throttle and reduced flow from an impeller intended for high rpm.. undersized or not).. can certainly compound the issue. FWIW.. most edlebrock street pumps I've seen are always going to flow more water than a standard factory pump(through better impeller design). Although I could see how a "HD version" could possibly be somewhat better in low rpm flow than an Eddy. Only when you get into the more serious intentioned Victor series pumps will the low rpm flow be sacrificed for more power and less high rpm cavitation. Which is exactly as Edelbrock describes them too. I run a 25% crank + 15% water pump underdrives on my 500 horse 385 Chevy with the regular Eddy pump and have no issues whatsoever using only a single core factory rad. With even slight airflow running thru it during slow cruise.. or when the e-fans kick on at about 210 after heating up at idle.. it runs at/right back down to about 175'ish temp(w/ 160 t-stat). Also keep in mind that horsepower makes heat.. so if this motor isn't anything excessive?.. you may be running a less than optimum tune on it as well which can have an impact. PS. I run fairly high concentrations of watter wetters in all my junk because it allows slightly more agressive tunes and maintains greater margins.
Make sure you your running 50/50 or more water. Straight antifreeze will not cool it. Also, the higher pound themostate is doing good, the poundage pushes heat out of the block if that makes sence to you. I'd also run a 180 degree thermostate. It holds shut longer and allows the coolant in the radiator to cool off better. Most people think it lets the coolant out sooner to cool, but it also has to stay in the radiator to cool off to work. It may not make heads or tales to you, but try it. Money back gaurantee.
I think the motor is at most making 425 HP and my mechanics definitely put 50/50 mixture in. the local "experienced in hot rods" old man claimed that the pump would keep the car cool on the street even when i specifically asked "will the car have heating issues at low rpms with this waterpump". I wanted the aluminum one to save a little weight. when you add up all the little things, it definitely adds up, even if it's only aluminum heads and water pump instead of cast iron and a chromoly flywheel instead of steel. The car is indeed quick now (considering the estimated 6.35:1 power-to-weight ratio), but i want it to be maintenance free above everything else
They're not underdriven accoding to the description. It implies that the pump is slightly overdriven. Did you notice the pic ? The crank pulley has two sheeves and it shows the belts running around either side of the waterpump pulley ? I guess to illustrate that you can get a set for either std or reverse rotation pumps. They look pretty much the same as the pulleys I'm using, the waterpump pulley about the same diameter as the crank pulley.
The increased pressure raises the boiling point of the coolant mix. It does not push the heat out any faster. A 180* T-Stat stays open pretty much all the time, once the operating temps get past 180*, no different than any other rated T-Stat. It only takes a few minutes longer (actually probably not even that much longer) but once it's there, it'll stay open til the temps drop below 180
The picture isn't quite accurate. the forward most pulley is connected to a power steering pump. I removed my power steering system about 10 years ago in favor of simplicity and increased performance. The kit only comes with a single sleeve crank pulley, they put the dual sleeve picture in for convenience since it's hard to find a picture of just the crank, water pump, and alternator. Anyways, from what I can gather, there's nothing wrong with my pulley set, but instead I need a standard flow water pump. Simply because the high flow water pump coupled with the overdriven pulley set, my guess is that the coolant is moving too quickly through the system to cool properly, correct?
I've also heard that switching the radiator out for a crossflow radiator will solve the problem, any thoughts? of course, with the newly added taurus electric fan, I'm not sure if it will mount to a crossflow radiator...
MIne is a down flow aluminum. I got here (this forum) just in time several years ago to get in on a run of these someone had made in China, it was basically a bolt in but made in aluminum. A high volume pump will not lfow too much, you want more flow at lower rpms for street driving. I suspect your pump is a high rpm unit designed to flow less to keep it from cavitating at high rpms. If you want to compare, then run to the local parts house and get a late 88 Crown vic pump and bolt it on and see if it helps. If it does, then you can sell the Edelbrock so someone else, a rebuilt Vic pump sells for around $40, even a new unit is around $80. The late 88-91 is aluminum bodied. The pumps made before that date are iron bodied.
