what is the difference?

[harshman]

i have a single pass radiator and can get my hands on an aluminum dual pass racing radiator. what is the diference of the two?

[CarlC]

Stock radiators for our cars are single pass, the return is on the LH side and the tank is full height. The exit is on the RH side and again the tank is full height. The coolant only makes one "pass" through the core.

Dual pass radiators seperate the flow into two horizontal halves. The return will be on the upper RH side but the tank will have a plate that makes the tank 1/2 height. Flow is directed through the upper 1/2 of the core to the LH tank. The LH tank is full height. The flow travels back to the RH side via the lower 1/2 of the core. The exit is on the lower RH side.

For our cars it usually means spending some time at our favorite parts store to find hoses that will fit. An adjustable thermostat housing makes fitment easier.

If the price is right and mounting either a shroud or electric fan is workable then it's a good deal. If it's been hacked it's not worth the time and expense. The MarkVIII fan works very well with most aluminum radiator setups.

There's some pics and info on the C&R Racing dual-pass radiator that on my car. See the sig. below.

[harshman]

ok i get that, here's my problem

https://static1.pt-content.com/images/noimg.gif

what are all of the fittings for?

[Matt@RFR]

Looks like a regular hose going to the pump and two -12's coming from the motor, a temp sender, and on the other side is the -4 overflow line.

Total guess here, but some people use a remote pressurized water fill to fill the radiator back up after it has puked over...is that what the second fitting by the water neck is?

[harshman]

it's the two 12's part that has me corn-fused. how does that work? i am used to the big hoses - one on top and one on the bottom.

[Matt@RFR]

I'm guessing the radiator is used, right? What kind of car was it in? What motor?

I'm sure someone is gonna come along and know exactly what that is (where the hell is Tim?), but my guess, for now, is that if I remember correctly, Yates heads have the water outlets in each head, and they go directly from there to the radiator. My memory is fading of my time in an engine shop though.

I'll get Tim in here and see if he knows.

[harshman]

C&R racing radiator, used in an ex-Winston car for one race at Sears Point, then pulled off and left sitting as a backup. Was never used again.

Dimensions: 30" wide x 17 1/4" tall x 4" thick, dual pass

[Drewhelm]

I have the same radiator in my 69 Firebird. You can cap most fittings. the upper right fittings are 20s not 12s atleast on mine they are. You can cap one and use the other. Lower hose is standard 1 3/4. There is an overflow outlet on filler neck above the top of the radiator, the others are I believe return lines, but I don't use them so they are capped. When I bought mine off e-bay all the caps were already installed.

Regards,

Drew

[Matt@RFR]

Drew, they are -12's....it's written on the radiator!

And with that size, you can NOT cap one off. -12 = 3/4" ID = not enough flow.

[harshman]

so, can i use this with my stock type cooling system? i can pick it up for $100. IMO i guess i would need some exotic plumbing to make it work or install a new 1 3/4" hose fitting up top.

[CarlC]

I may be way off base here and Tim can set me straight, but there are some drawbacks to this setup.

First is cost. The up front cost of the radiator is low, but it will require either lots of AN fittings + manifold mods OR re-working the return on the radiator to accept a standard hose. To rework the radiator to accept -20 the cost of the rework + hose/fittings will be big $.

The other factor is the thickness. If this radiator is truly a NASCAR 4" core I would be concerned about airflow at low speeds. That radiator is designed to work with airspeeds that are much higher than what we normally deal with. Getting the fan system, either mechanical or electrical, would also require some fabrication due to the extra thickness of the core. A MarkVIII fan would be tough to fit even with shroud trimming.

Do Cup cars have integral oil coolers?

[Ralph LoGrasso]

Carl,

I need to ask you to please resize your sig. pic to 75x250 pixels. This is being done to minimize download time for dialup users. Thanks for your cooperation, it is much appreciated.

[harshman]

gotcha. i think although it looks great, i'll pass.

[chicane67]

Matt nailed them all.........

The dual -12 lines were used, one from each side of the engine as the return. The fitting on the lower right is for a temp sender/switch and the -4 on the left header is for the overflow/surge system used by those chassis builders.

Draw backs are the increase cost of the return lines. I should know, my -20 return upper hose was right around $250.00 by itself.....probably about the same for two -12 lines complete.

Second BIG problem. "Fins per inch". Works great on a cup car.....sucks on a street car.

And Carl, dont resize your sig picture. It ROCKS!!...... Ralph is just jealous......and screw the dial up users. STEP UP AND GET SOME REAL SERVICE crackers !!!!

[CarlC]

Dang, I'm not used to such nice requests!

How's the resize?

I could not find it again but somewhere the specs for the sig photos list 29.5kb. I sized accordingly and the system bought it.

Now to show my internet ignorance. How do I make the line in my sig a clickable link to my website?

[ZZ430]

Now to show my internet ignorance. How do I make the line in my sig a clickable link to my website?

Carl, it's none of my business, but try something like this.


Carl's 68 Camaro (http://www.geocities.com/casanoc)

(Click "quote" on my post and you can see how I did it.)

[Drewhelm]

DOH! Sorry, Mine has 2 -20s. I bought it off e-bay then called C&R for specifics. I was told by C&R that it probably wouldn't work in my car, because it was too thick and the fins per inch were probably too high for street. It too is a 4 inch core. With a taurus fan I have absolutely no clearance issues in from of my .060 over Pontiac 455 and it keeps it at a cool 180-195 even in 100+ Texas heat.

Regards,

Drew

[CarlC]

Thanks Don!

[ZZ430]

No problem Carl, a car that nice needs to be seen!

[chicane67]

DOH! Sorry, Mine has 2 -20s.


Wow......2, -20 return lines. That is a pretty serious system to be utilizing 2, -20 returns.

[porschev8]

That radiator will probably work fine with a good set of H/P Spal fans mounted on the correct shroud. Removing the two -12AN fittings and replacing them with a 1.5" hose connection wouldn't be that difficult to do and shouldn't cost more than $100.00 to have done. I wouldn't worry about the core thickness too much, in the picture it appears to be an "Intermediate" track radiator, which is normally used 1 - 1.5 mile tracks so it shouldn't be too hard to move the air through it unless it has an extremely high fin count (more than 18 fins per inch).

-Tim

[yody]

hey tim, any progress on my rad/fan setup? :)

[porschev8]

We're still waiting on 14" Spal fans. Hopefully they'll be here next week.

[JamesJ]

Not saying that this radiator is like this but some have lines for the oil cooling. This cleans things up and its an all in one.