asubennett

iTrader: (6)

Notice that my Edelbrock fuel rails getter rather warm after some spirited driving. Thinking about wrapping them in gold reflective tape. Anyone ever done this here with LS engines. I know BMW guys do it a lot. See below.

https://www.google.com/search?q=gold...9%3B1024%3B576

stevieturbo

The rails are situated in a roasting hot engine bay, if you've an alloy intake they're bolted directly to that heat source.

the only thing then cooling the rails...is the fuel passing through them. Which in turn is then heating the fuel.

Vicious circle ?

I'm sure the gold tape can do no harm, I really cant see it doing much good though

Ultimately the only concern is hot fuel ( monitor and log temps then ), and if it is higher than you like, just fit a fuel cooler.

asubennett

iTrader: (6)

Yeah, thought about the fuel cooler but I really believe the heat transfer is radiant not conducted. The gold wrap might help deflect some of that heat transfer perhaps...?

I'll try it and take rail temps before and after. If nothing else they look pretty wrapped gold.

stevieturbo

radiant, conducted it really makes no differences.

You could avoid radiant heat in short bursts. But the engine compartment does not run for seconds at a time, and it's basically a huge heater at 200degF, and that's not even including exhaust heat etc.

So wouldnt matter how much gold you stick on it...it's still going to get hot.

And whilst gold could be deemed a reflector...gold will also be a very good conductor too.

If you want minimal heat transfer, maybe someone could make plastic or composite rails.

RonSSNova

iTrader: (3)

Stock truck rails are plastic. Ugly, but plastic.

I'm wondering if you could have the rails thermal barrier coated.
You could also wrap with header wrap.
There are other reflective wraps available. Kind of an awkward thing to wrap though.

The rails only bolt to the intake in 2 places. So the thermal xfer there should be minimal.

To see if any solution works would require some temp measurements.

Try some stuff. I've thought about it too.

Ron

69-chvl

iTrader: (11)

Probably better to vent all of the underhood heat off somehow.

forcd ind

iTrader: (7)

Nascar engines wrap the rails, and the cross over pipe, so it must do some good-of course they are looking for even the slightest little thing

LS1-IROC

iTrader: (4)

Just about any form of heat management under the hood of a high output engine is going to be a benefit, whether it's measurable or not is debatable.

stevieturbo

And until you've logged fuel temps to establish if the heat is a concern....all the talk is meaningless.

And if heat is an issue...by far the easiest and most effective way of dealing with it, is fitting a cooler.

asubennett

iTrader: (6)

Cooler and wrap probably will help the most. A big indication to me will be simply a touch test. I cant touch the rails as is after a cruise they get hot. Will wrap with the gold and see what happens. I bet I can touch them after. Not super scientific but a good start.

stevieturbo

Touch test is meaningless. The thing you would be concerned about are fuel temps.

Just fit a sensor and log them.

I have a very badly placed cooler, when stationary it will do little. When moving it should cool a bit.

But I've never seen fuel temps that are of any concern when the engine is running. Even when sitting queuing for a long time with engine idling etc.
And that's with a pair of 044's running all the time which some rant you should never do.

tblentrprz

a few thermal couples, i/f box and water pipe insulators and you're off and testing

V-seriesTech

iTrader: (5)

Want more fuel pressure but, don't want to heat up your fuel?

Belt drive.



Your/our injectors are insulated by O-rings, that gets rid of some heat transfer,...the rails attach by a bracket, if using an aluminum intake, just thermal barrier the mounting brackets that attach to the rail. That would honestly repel more then you think. You could also coat the outside of the rails themselves, keeping radiant heat out...or use some heatsheild armor to wrap around them. A fuel cooler is definitely a good option as well. Also to consider, the bends used in the fuel system. Lot's of sharp 90 degree AN fittings? Use Y's instead of T's when you can...etc.

Anything you can do to repel heat,..I don't think anyone could/should deter you from that. Do it to it.

stevieturbo

Only thing you need to monitor is fuel temps, presuming you've an ecu that can log stuff, all you need is a $10-15 sensor and some wiring.

asubennett

iTrader: (6)

Ha, yes. 2 4303's probably not helping fuel temps. But I start with a pretty low static base pressure. Not cranking up the FP too high.

@ Stevie Turbo, why would the touch test be meaningless? I am running Holley EFI, so yes, I could monitor with a sensor. But if it's too hot too touch that means the fuel inside is being heated. If it's cool to touch, presumably there is not heat transfer at that point. Am I missing something?

stevieturbo

Belt drive wont make a damn bit of difference to the heat imparted to the fuel from the hot rails and hot engine compartment...except now you've also the fuel flowing through a hot pump also bolted to the hot engine, in the hot engine compartment.

And certainly I've no problems with fuel pressure.

stevieturbo

As said, the rails are bolted to a hot engine, in a hot engine compartment.

The test is as meaningless as touching the engine and saying it's hot too. Of course it's hot, why would it be anything else ?

There is no way the rails are going to be cool, unless you're pumping chilled fuel through them, and enough of it to combat the heat imparted from the hot engine.

The only way to isolate from the heat would be to have totally non conductive rail mounts, and fully insulated rails. But even then, heat soak over time is still going to work it's way into the rails.

Just buy a cheap coolant temp sensor. I use Bosch motorsport ones for engine temp, oil temp and fuel temp. You could just as easily use the normal GM LS coolant temp sensor for same. It's same thread as the Bosch anyway

I screwed my fuel temp sensor into a small manifold that distributes fuel to the rails.

V-seriesTech

iTrader: (5)

Very nice...and smart with the low pressure setting. Another thing many people do is run too high of base pressure.

Electric pump(s)=generate heat.

Belt drive pumps, can be mounted wherever YOUR imagination allows. If that is on a hot engine, so be it.

I think you're over generalizing towards the negative. Any step along the way to combat heat, should be used. I again don't see why you'd deter him from that. Test. Coat mounting brackets, insulate rail(s). Test. After going through major heat/thermal issues with my own build, defiantly a believer in coatings/insulation(s).

chuntington101

Totally agree Steve! Unless your having proven fuel vapor in rail issues or you have very high fuel rail pressure don't bother! OEMs do full hill climb runs and then leave the engine for 5 min to 'heat soak' and never boil fuel! You have to remember the fuel line pressure will help prevent the fuel from vaporising.

No point making a solution if you don't have a problem in the first place now is there!

PS. Steve your starting to sound like Max Torque off pistonheads with all your senssors.

stevieturbo

I've tested my own pumps, static test, and let them run for 20 mins to see if they raised fuel temp.

Yes they did, but really it was only by a very small amount. It will literally be nothing compared to the heat from the engine itself.

I'm simply saying whether wasting time trying to insulate, will actually make any worthwhile difference vs just fitting a cooler. Which will without question help cool the fuel.

Of course if fuel temps arent actually hot in the first place, then it's all a wasted effort really.

Hence I've said from the outset...log temps first, and then try and fix something if it needs fixed.