Messages

I understand about the high flow pumps. But I like to keep my car as much "off the shelf" as I can. Always easier to get a replacement in BFIowa

I don't understand other than BF IOWA?     All the new fangled high flow/volume pumps have the same footprint as the old ones making literally "off-the-shelf".... and for the most part water pumps do NOT have replaceable parts anywho! What are you going to replace? You can swap the high flows for a regular or visa versa without changing anything for the most part. Stewart actually makes a stock looking (iron) high performance pump that is literally hard to tell from the original!

But, the real quizical issue is that the newer high flow pumps such as TuffStuff, Edelbrock, Moroso and other quality replacements have much better support front bearing technology and have failure rates and product lifes that are expotentially better than the stock pumps.... and don't get me started on rebuilt ones!  They have huge failure rates and are *-poor at moving water!  I know.. I have tested just about everyone that is on the market!

Also, I would easily argue that the newer technology is not only better as far as performance is concerned (typical stock pumps deliver only 30 gpm at highway cruising speeds/rpms (ie,2500) to a Stewart Stage I that delivers about 55gpm in comparison and idle conditions are really bad for stock pumps in comparison), but I also would tell you that your old pump is robbing you of horsepower at cruise (could be up to 6hp compared to just 1.7 for a typical highflow model) causing more heat to be generated and of course eating more of that precious gasoline.  At full throttle some stock water pumps are so inefficent that they take up to 10 hp at 5000 rpms whereas the Stewart Stage I will only take slightly over 2 hp!

So, I am not saying that you have to run these things... but we all spend all kinds of $$$ on other upgrade goodies to improve our rides, I just can't understand why folks wouldn't want to do this easy upgrade for better cooling performance, much higher reliability, and lastly but not least gas savings as well.  There are NO downsides to this ... and no I don't work for a waterpump manufacturer!  

I like to post this stuff not to pick on anyone .. .. or second quess what they want in their own ride.. but to bust the many myths of the cooling equation for these applications .. that's all.  

Well after 50,000+ mi all over the country in all kinds of temps and conditions without a problem, I'm not going to fix what's NOT broke.  My son always had a cooling problem with his 406 powered Jeep he built for off-roading until he went with a double pass. Again not broke needn't fix. Both of these radiators are aluminum 2 core with big tubes. Neither car runs a high flow water pump either

I like the "if it's not broke.. don't fix it" addage for sure.  Also, let's not confuse double-pass with double-row. Not the same and I think it can get confused sometimes.

But, in case you are interested, high volume/flow pumps are a great insurance policy for both cylinder temperature differential and hotspots (some hotspotting can occur without you knowing it! They improve flow throughout the cooling manifold and especially in the rear cyclinders regardless of radiator construction.   I think they are a great bang for their cost these days.

Well I'll stick with my triple pass as it's proven to work for me on the street.

I agree!  This is not about changing your multi-pass series out unless they are NOT doing the job!  My statement here was to make everyone aware that single-pass, large-tubed aluminum radiators are the most efficient.

I would tell you that if you are NOT running a high flow water pump with your multi-pass (or any new application for that matter) that would be a good upgrade and certainly more insurance for higher flow numbers meaning higher cooling capacity!

I hate to burst bubbles here... but there are several misunderstandings in this thread that I would like to comment on for future reference.

Multi-pass radiators are very good for "constant RPMs" situations such as racing applications etc. But, for the street they are NOT the most efficient. That does NOT mean they won't work or improve YOUR situation per se. ....just that they are not the best technology for street applications.  

For example physics dictate that double pass radiators require 16x more pressure to flow the same volume of coolant through them, as compared to a single pass radiator. Triple pass radiators require 32x more pressure to maintain the same volume. Automotive water pumps are a centrifugal design, not positive displacement, so with a double pass radiator, the pressure is doubled and flow is reduced by approximately 33% and we all know flow is king! Modern radiator designs, using wide/thin cross sections tubes, seldom benefit from multiple pass configuration.  The decrease in flow caused by multiple passes offsets any benefits of a high-flow water pump also.  Common double or triple-row big tube aluminum radiators are king when it comes to shear cooling efficiency.

 I should of added an update with this post.

No air flow restriction from the electric fan.

This is a myth!  Electric fans will NOT block airflow to any significant degree.  There are plenty of new OE cooling designs (such as a BMW X5) that use front electric "pusher" fans as primary cooling fans and are very efficient.

I did notice one strange thing. When i turned the lights on the temperature gauge rose from 190 to 210 degrees.   I turned the lights off and it went back down. Next, I turned off the dash lights. The gauge went back down.  :?  Then I check the temperature with the infrared thermometer. Matched the gauge reading with the lights off.   Something going on here.

Don

What is going on here could be a ground.... but my money is on voltage drops occuring at the dashboard power buss.  This is very common.  What happens is the source is paralleled at the same point where the lights are being source. The wire length or size is not sufficient to carry all the load and therefore voltage drops to the temperature sensor which uses the voltage as reference for a reading. When the voltage dips at the meter then the meter  is affected.  I have seen this time and time again.  I would suggest that you put the headlights on a relay sourced from a breaker protected lead from the battery bus to aleviate this phenom.

Thanks for all the outpouring of support and thoughts!  I appreciate it for sure.

I can't start to tell you (and most of all...those who knew him or just met him) how much the "car community" has meant to my Dad.  And...you are all a part of this... and made his life so qualitative the last few years.  He just fell in love with all the people!

http://www.chevytalk.org/threads/showflat.php?Cat=0&Board=UBB4&Number=1695812&page=0&fpart=all

My take is a tad different.  Actually, the hotter the "peak combustion temperature" the more hp you make. The engine coolant temps may or maynot have something to do with that.  

If your nominal engine temps are running so hot as to affect the incoming fuel/air charge temperature (namely increase the temperature), the less dense the charge will be resulting in loss of power (this is why outside air induction works to make hp).  So, keeping fuel and air cool is important if you are interested in power.

Today's modern engines are designed both from materials and function to run a hotter thermostat. This has to do more with pollution issues but combines for more effiicency as well.

Most of the crate motors of yesteryear's design (such as your 502) are made for the 175 to 210 degree range. In fact, running less than 175 reduces not only power but also is not hot enough to work correctly with most oils (can't burn off all the moisture etc).  

I would recommend a "balanced" (AKA high flow) 180 degree thermostat from Mildon, Mr Gasket or Robert Shaw.  These are highly effective at controlling temperature, higher flow and won't fail in the closed position.

Here's a great discusion page for more... http://www.performanceunlimited.com/illustrations/thermostats.html

Gone!

At the host hotel Marriott Airport....sweeeet!  I believe $99 no smo and ya have to like the person you are sharing the room with really well...same king bed.

email me at hotrodsrj@bellsouth.net

I'll be there with my Dad's 55 in the same usual spot me thinks.  This is probably his last year doing the 55 thing (he is ill)....so stop by and say hello to a fantastic guy, WWII vetern and greatest Dad in the World.  

hope it helps you out.

it sure made my coupe run better.

I didn't wanna say it out loud, but that Steve Jacks feller is pretty smart.

didn't want him to think we like him or anything.  


Vance

Awwwwwwwwwwwh Shucks!  I like you guys tooooo!

First, let me give credit where credit is due. The article that you linked to is actually from John Z over at Camaros.net.  This is one of the best expressed tech explanations that I have ran across in years...so it's John's discertation....not mine.  But, it's exactly what I have learned and know...and in perfect form.  Another link here... takes the garbage numbers out that were somehow scrambled in the text copy.  http://www.camaros.net/forums/showthread.php?t=70263&highlight=vacuum+advance+101

Also, my experience with the ZZ4 HEI is that you will definitely need a full time vacuum advance for this...but it also has a tendancy to allow too much vacuum advance under light and moderate throttle conditions.  So, a Crane adjustable/limiter is usually needed...or it will sometimes detonate or ping due to the excessive total vacuum advance.  Limit it to 12 degrees please.

Also, the Edelbrocks AFB carb can have an "off throttle" hesitation due to the booster springs that come in the carb by default (orange).  The ZZ4 will make at least 18" of vacuum and need the highest booster spring (silver) or stiffest one you can get.  I suggest you also make this change and watch your hesitation disappear.

My two sense.

Sorry...sorry...sorry to hear that.  That's about what I am in age...and it's real work to keep on top of your health.  I don't wish cancer on anyone ...it's a horrible death and the poor guy and family that has to watch this awful event.

On a related subject....and unfortuneately.. I read (AMA journal of sorts) that this "hobby", "occupation" or "lifestyle" (building and professional maintenance of custom cars and related activities) was one of the worst for your health. The stated reasons were exposure to chemicals (esp aeromatics and paints), excessive tobacco use,  abuse of the muscle skelton system (in other words... joint degradation), very poor eating habits (all you have to do is look around at any event), and lack of REAL exercise.  This group had the highest obesity, heart attacks, strokes and cancer rates compared to 133 other mainstream "hobbies" or "occupations".  

Sorry ...didn't mean to hijack the thread.

The overwhelming majority of DC motors are optimised to run in one direction.    In order to negate the effect of rotor winding reactance, the brushes not are mounted at the true symmetric point, but advanced slightly.  It has some similarity to the ignition being advanced on a gasoline engine.

Even where DC motors are used in applications where they are required to be reversed, such as electric winches or garage door openers, they are still optimised for the high load direction and if they operate at lower efficiency in the low load direction it does not matter.

Any person doubting this only has to take a bare windscreen wiper motor, and run it first in the design direction then backwards by reversing the connections.   You will not need a fancy optical tacho to pick up the difference in speed, it will be quite apparent by the sound from the running motor.

In the case of fan motors, the manufacturers may make the motors "straight up" to save the need to stock different models, but I suspect they try to achieve maximum efficiency and if that is the case the motors will be designed for a particular rotation just like the curved blades.

Hey Peter...good info ....and I agree....I have seen alot of DC motors that are "rotation direction specific" for optimization (mostly in aircraft slaved motors in my experience).  However... I have had several conversations with Spal, Derale (esp these guys) and Hayden engineers that choose these motors specifically because they are "multi-directional" and lose no "working ability" running in either direction...again according to them.   I have to take their word for it...as designs of these can vary. But, these are pretty simple designs and relatively inexpensive motors and I have tested several multi-directional fans in a "airflow box" and they perform (CFM and RPM wise) almost exactly the same in either direction.

John,..... I assure you that the motors on these fans are simple DC motors that run as good in one direction as the other...they really don't care....so I don't know what's up with directions being wrong...and/or the leads are colored wrong or whatever...but it really doesn't matter.  The fan will work at the rated specification either way.  So...enjoy.

A clarification about my comment about the blades/shroud combo and why it DOES or at least COULD make a difference which way the blades spin for MAXIMUM output.  SIMPLE flat blades with a equal pitch throughout the blade length from both sides can be reversed and used that way with no penalty in CFM production as pointed out.  

But, for example.....if you think the ever popular Spal purported "straight-bladed" fans are simply reversable by swapping leads and plug and play...you are wrong at least from an airflow perspective.   They have a slightly "off-pitch" designed blade from one perspective that makes their direction imparitive to produce maximum CFMs. Note the difference in part number here for "pusher" vs "puller".  http://www.spal-usa.com/fans/automated/tech_sheets/2041-2055.pdf

Also in the same matter, "skewed" blade designs will NOT produce the same amount of air one way...and then simply reverse the leads of the motor and produce the same the othe way.  Here is a classic "skewed" design that if you want to reverse the direction of the fan...then you have to turn the blades around too.



These type of "skewed" blades are designed for the leading edge of the blade to turn in the clockwise direction (as viewed from this side) and would lose about 30% of their output by simply reversing the leads.  All bi-directional skewed bladed fans instruct you to not only reverse the leads, but turn the fan assembly around too for puller vs pusher operation.  

Just a clarification.

210 Puller   http://www.flex-a-lite.com/auto/html/low-profile-electric.html
I am wondering if I reverse the leads, how much air it will move?

John.....these fans are only made from a shroud/fan blade design to pull. So, if the blades are running the wrong way the correct way is to reverse the leads on the fan and it will deliver the specified CFMs.  Are you sure that you have followed the directions for the relay/motor interface.....but it's pretty easy just to swap the leads and go! No biggie.

Let's us know how it all works out for you?