As requested...

I don't have this mounted on my car yet... in fact this isn't even the car with the fuel system on it, it just happened to be on the lift. There are two locations that I like for this cooler -- underneath the diff on the rear cross member, and between the sway bar and rear crossmember.

Pics:

underneath diff


underneath diff


between swaybar and crossmember



The swaybar location is easier to plumb IMHO but would also place the cooler close to the exhaust pipes. Might have to wrap the pipes or provision some other thermal protection.

The diff location is a little more concealed/stealth but the heat of the diff may become a problem. I don't know how hot it gets over time.

In either case, the fins of the cooler can be mounted slightly lower than the crossmember so that as the car is moving, air is running across the fins. Should provide for good cooling.

Hope this helps.

 

Thanks for the pics Tony. They are worth a thousand words

 

Tony,

Have you given any thought to installing it in the rear brake ducts? The rear brakes really don't need cooling but the vent can stream plenty of clean cool air over the fuel cooler.

 

Looks beefy enough to stand up to road debris.
What do those go for?

Oh, I've had pretty good luck insulating exhaust with heavy duty aluminum foil. Used it on the headers in a mid-engined car. Might even look a little more trick than header wrap. Seemed to work best if I wasn't too neat about putting it on, crinkling a layer a bit before putting on the next one....some trapped air space.

 

The last location looks good. Can you turn it around or point it forward because the more air you can get across it, the more it will cool. You want reasonably laminar flow as this will cool more efficiently then turbulent perpendicular flow.


Mike

 

You going to cool the return side or feed side??

 

why would you cool thr return line, serves on purpose in my own opinon,

 

The idea is to keep fuel temperatures in the tank low so fuel pump performance won't be compromised.
Fuel returning from the engine compartment would probably be the hottest, so best heat exchange might be there.

See his temperature measurements at http://forums.corvetteforum.com/show....php?t=1415268

Fuel tank and fuel rails got up around 165 degrees F.

 

Correct. I actually think that cooling the return side will provide the most bang for the buck. As you mentioned the intention is not to make the fuel leaving the pump cool enough for the motor... it's to make the fuel ENTERING the pump cool enough to not cause a pressure drop. Based on my measurements it appears that with aftermarket rails, the fuel is hottest when returning from the front of the car. That's why I think cooling on the return is a good strategy.

I don't know how temps are affected on stock fed/stock rail cars, those were just measurements from my aftermarket ECS setup.

Re: price -- it was something around $100, I don't remember exactly. It has -8an ports on both sides and a check valve on one side. I'm actually looking forward to experimenting with the check valve on the return, it may help me keep pressure in the rails between cranks.

Re: location -- the bolt holes for the unit are on the side I have facing the aluminum crossmember. It could certainly be angled differently by fabbing up a simple bracket. Yes, the unit is very beafy, the fins will easily withstand rocks and other road debris. I don't think I'll put it near the brake duct vents, if for no other reason than putting it there would actually be harder than putting it in the few spots I took a picture. In those spots I can just drill and bolt, anywhere else I'll likely have to fab a bracket.. pull the wheel, wheel will liner, etc. work around my pump.. you get the picture

 

Cooling the return side would also be safer, as its low pressure.

And fitting a cooler in the feed/pressure side, could also restrict fuel flow to the engine, which wouldnt be a good idea.

Any more pics of the cooler itself ?? its it just an alloy tube with fins around it ??

I'll be fitting a 13 row Earls "oil cooler" in my fuel return line very soon.

I'm just mounting it under the car. it wont really be in direct airflow, but its mounted well clear of any hot parts, ie the exhaust etc, so when on the move, I think it should offer good enough cooling.
I may build some sort of small duct, to direct air onto it, but see how it performs first without it.

 

Great idea and once you get this mounted and up and running let us know how this works, looks like something I need here in the heat of Texas and the return side is the way to go we want the fuel in the tank as cool as possible to keep our pumps from over heating as this is probably the biggest contributing factor to the walboro style pumps crapping out. Pretty much why I very seldom let my gas gauage go under a 1/2 tank, keep my primary tank full, especially when I want to abuse my car

 

i though tit would be best to mount on the feed side! that way you get the coolest (ie densist) fuel to the injectors!

i know thats what F1 guys do but they do run VERY high injectors presures!!!!

thanks Chris.

 

The nice thing about the return side is
* you are cooling less fuel
* you are cooling it before it hits the tank and heats the rest of the fuel
* it is MUCH easier to plumb
* it can cool both the primary fuel pump and secondary fuel pump in one cooler -- my fuel feeds don't come together until they hit the front of the car. wouldn't make sense to put a cooler up there, there's no good place where the car is nice and cool.
* the cooler would be immediately after the biggest (imho) heat sources -- the pumps and the rails, and therefore have the biggest heat delta (which should provide for the best cooling on a passive cooler like this one).
* the cooler doesn't add a restriction to the system that the system would "care" about

If done in front of the pump(s) plumbing becomes complex and may reduce flow to a point that the cooling effect is not worthwhile.

 

I'm really interested to know how much your fuel temp. is going to drop?!?! Also wondering what happens when air temp is 105 here in Dallas and the pavement temp is near 130 or higher right now. Just wondering if all the radiant heat from the hot streets is going to affect the fuel temp the short time the fuel in actually in the cooler. Please keep us posted

Shahram

 

I'm curious about under car temps too.
Anyone have one of those indoor/outdoor thermometers with the wireless outdoor sending unit? The "outdoor" unit could be zip-tied under the car, and transmit readings to the "indoor" unit in the car.

I had one from Radio Shack, but it died.

 

Won't know until I try it... gotta finish up some work on the convertible first. Only other thing I can say is that I would speculate that this location is cooler than the location of most front mount intercoolers, and will probably get more airflow if the fins are mounted lower than the rear crossmember (direct airflow instead of airflow that is deflected by the front air dam).

 

I agree. A buddy has his rear cooler and trans cooler in these locations. He is a road racer and also thinks the rear ducts for cooling brakes are not needed. One other spot might be in the tunnel?
Robert