Radiator advice

[brad smith]

1989 red devil setup for autocross.

In the middle of summer I was struggling to keep the temps in the 160 range. I think I found the problem:


Those are the original school bus heater cores. Also because of how the fans were mounted they have bent the fins over (although the construction lends itself to damage, the fins aren't like a traditional radiator and extend past the tubes by quite a bit.

Anyone ever try anything like this? (ebay link) I would have to block off some ports but it's exactly the right size. If not any other ideas on radiator sources?

(ideally they would be 16"x9" 2" thick.)

[Jim Murphy]

Go buy a REAL aluminum radiator to fit. There are posts/threads on this forum about this issue. BTW, having the highest CFM fan available attached to a sealed shroud will help. AND an inline water pump that both can be run with the motor off between runs is the best way to bring it down to 100 degrees. You only have a restrictor in place of the thermostat, don't you?

Jim
Been messing with these cars since 1982.

[brad smith]

I've read though all of the tech posts looking at info about radiators. Was hoping to find some info on what radiator to source but just yesterday found an aluminum radiator from a Yamaha 700 ATV that will fit perfectly so 2 of those are on order. Just need to source an electric pump so if anyone can point me in the right direction there that would be a big help.

Everything else on the list is just about figured out - new high CFM fans, and yes - the thermostat has been modified to just the plate (so it's wide open)

thanks for the advice -
Brad.

[Jim Murphy]

Get an in line pump from a RV catalog as the water temps will rarely get too high for it.

HTH,
Jim

[Jeff Blumenthal]

The Davies Craig water pump is what most use for Solo. Getting it direct from Australia will save $$.
http://www.daviescraig.com.au/Electric_ ... tails.aspx

[Jay Novak]

This is the pump you want. I have physically tested everything on the market.

Bosch makes 3 different flow rates. This is the deal. 12 gal/min for the high capacity Bosch, measured.

http://www.ebay.com/itm/GENUINE-FORD-RA ... 0834766754

Here is another link.

http://97.74.32.155/files/pump.pdf

You can get them for less.

[brad smith]

awesome! thanks for the info all - I really appreciate it.

Brad.

[Bill Butterworth]

What year and model Yamaha 700 ATV radiator did you use? What are the width, height and thickness?

Thanks, Bill

[brad smith]

Keep in mind - I only autocross with my car (and i have electric fans)...

i installed 2 of these: http://www.ebay.com/itm/291185624552?it ... m=&vxp=mtr

it's from a raptor 660 2001 - 2005. overall size is listed on the ebay page but I can tell you they are a single core - all aluminum rad. I still have my radiators run in series but I've done a couple events this year and last year after runs i would register around 150/160 on the thermo and this year for the last two events it's been 140. They are also a lot lighter than my old rads - saved about 6 lbs total.

I'll be switching my plumbing from series to parallel which will slow my flow rate down in each radiator - and hopefully get both rads to share the cooling load. I just need to make a couple 1" wye fittings for the plumbing.

brad.

[Jay Novak]

Keep in mind - I only autocross with my car (and i have electric fans)...

i installed 2 of these: http://www.ebay.com/itm/291185624552?it ... m=&vxp=mtr

it's from a raptor 660 2001 - 2005. overall size is listed on the ebay page but I can tell you they are a single core - all aluminum rad. I still have my radiators run in series but I've done a couple events this year and last year after runs i would register around 150/160 on the thermo and this year for the last two events it's been 140. They are also a lot lighter than my old rads - saved about 6 lbs total.

I'll be switching my plumbing from series to parallel which will slow my flow rate down in each radiator - and hopefully get both rads to share the cooling load. I just need to make a couple 1" wye fittings for the plumbing.

brad.

Not big enough, even with fans. Parallel plumbing might bring the temps down a few degrees. More likely you will not see a measurable difference as the rads are just too small.

[brad smith]

I have my third event this weekend - I'll report back with how they did and some pictures.

[Cory McLeod]

When I tried converting from series to parallel, I had trouble finding 1" Y connectors. Here is what I used.

https://www.grainger.com/product/ELDON-JAMES-Y-Connector-23CM53?functionCode=P2IDP2PCP

Can't testify to their long term sturdiness, because I only used them for one day, but thought this might save some folks the time of trying to find a source for Y connectors.

[Jay Novak]

When I tried converting from series to parallel, I had trouble finding 1" Y connectors. Here is what I used.

https://www.grainger.com/product/ELDON-JAMES-Y-Connector-23CM53?functionCode=P2IDP2PCP

Can't testify to their long term sturdiness, because I only used them for one day, but thought this might save some folks the time of trying to find a source for Y connectors.

Great solution Cory. Should work fine.

[brad smith]

nice find! I had been looking around and thought I was going to have to make my own.

Thanks Cory!

[brad smith]

Cory - thanks for the time saver! I have a couple of those fittings installed. saved me a lot of time vs. making them.

This last Sunday I finally had a warmer event (the previous two were cold and rainy). After pulling into grid from my runs the engine was never over 150 so i'm happy. It may not be the best option for cooling but so far it's working.

[Jay Novak]

You are loosing at least 5 hp at 150 degrees F

[brad smith]

last Sunday was my first event with everything in place. Radiators in parallel, electric booster pump wired to run off grid battery when engine off and the on-board battery when engine on. It was about 90 degrees, with 60% humidity (after a popup rain shower in the first heat that put about 1" of water down on the course, but I got dry runs by my heat)

anyway - my cheepo electric water temp gauge said I was starting each run around 110-120 and by the time I pulled into my grid spot it was around 140-150. I will say that I had some major issues up at spring nats with a co-driver, but that was before the electric water pump.

I've learned a bunch about cooling. It's important to have as much flow as possible - the turbulence in the coolant is important to keep lower temp coolant mixing with the higher temp coolant in the passages of the engine and keep localized hot spots from forming. It can not flow too fast - speed is good. (so is turbulence inside your radiator - if the flow is too laminar the energised water molecules won't shed their energy because they become trapped inside the other water molecules and it's like an insulated sleeve.)

Cavitation though, that's bad. Make sure you have all of the air out of your system. If you don't you won't get high enough pressure to resist cavitation at the water pump.

Also - when I switched my setup from series to parallel - it halved my flow rate through the radiators. It wasn't fast enough to cause the turbulence inside the radiators needed to shed the energy efficiently. I was better off in series - until i got the booster pump. Now it's flowing like crazy through my engine and rads, keeping everything nice and cold. And i'm down on total weight for the system. The old radiators were heavy - the new ones saved me almost 5 lbs total even with the electric water pump.


Is there a better way to cool the engine - definitely. In my case it would have required more body work changes than I had time to do. In a couple years I'll probably revisit it and drop in larger radiators to help in keeping the system as cold as possible.

[Jim Murphy]

IIRC, you do have large (covering most of the radiator and shrouded in) high volume radiator fans as well - correct?

[brad smith]

Sorry Jim - somehow i didn't see this question. yes I have large-ish 8" fans that are ducted tight to the radiators. As a matter of fact, the entire airflow is fully ducted tight to the radiators - up to the pusher fans - through the radiators - out the top with no chance for the hot air to sit under the bodywork. The old Red Devil (89) bodywork isn't the lightest or flashy-ist but it's get the job done in that department.

Jay / et all - can you recommend a radiator for an auto-x car that hopefully won't break the bank and will fit in a side pod on it's back? (think like the invaders - but hopefully not quite a long. I don't have as much front to back space in the pod).

thanks guys - hope your off-season projects are going well.

[Jay Novak]

Yes, there are lots of aluminum radiators on EBay that are replacement radiators for production cars. Look for dimensions and double row. They are all made in China but I have been using them for years with never a problem. Find one that fits your package space. Search on eBay for aluminum radiator. You will probably find several.