Heat Soak

[Deathwish]

Ok then where do i start. I've got an R33Gts-t. Its a standard engine but with a race head gasket. Its got a greddy inlet plenum with 740 injectors and a turbometics A.65 series turbo and a full 4" straight through exhaust. I've got a race rad and a greddy oil cooler and filter relocator. Its putting out 549bhp on the top map. Heres the problem, im having really bad heat soak/transfer to everything under the bonnet. Im after some advice and ideas as to how i can reduce the heat problem. Its not overheating or anything but everything is really hot. I've wrapped the manifold and got a heat shield on the turbo. Im considering putting an water/oil cooler on the gearbox to help there.

[gotRICE?]

lol @ 409KW on a stock RB25!

But even so... its an engine. It gets hot. Unless its sapping the performance its not actually bad to have a hot engine...

If your really worried raise the rear of the bonnet, or get a vented bonnet.

Edited July 7, 2009 by gotRICE?

[blind_elk]

... raise the rear of the bonnet, ...

How can that help? It's a high air pressure region at the base of the windscreen. How else do you think you get air in through the heater vents. Or how those "reverse scoop" bonnets worked on old-school Falcons and Commodores? All you will do is push air into the engine bay. Then you will have overheating problems because there is no pressure differential to allow cool air to come in through the radiator.

Back to the original problem - it's an engine making lots of power, of course it's going to generate some heat.

[Deathwish]

thanks for your replys guys. I have a carbon triple vent bonnet on it already. I've been considering an intercooler mister to try and cool the inlet charge a little and maybe put a mister on the oil cooler while im at it. I've also looked into fitting an electric water pump which would keep the water circulating after the engine is switched off for a while until the engine temperature has dropped to a level im happy with. What about venting air from vents at the bottom of my do-luck from bumper up into the engine bay at the inlet plenum and manifold to try and keep them cooler when driving?

Regards, Thwish

[Ultimategtr]

Is it a track car or road?

Do you always get heat soak? or just after a short drive?

raising the rear of the bonnet will kind of help, ONLY if youre not racing that is.. ie on the streets.

Why dont you take out the AC? Or perhaps run a few elec fans between the fmic and the radiator?

The other question, is it a high mount or low mount turbo?

[The Dan]

How hot is it getting? In degrees celcius please.

And not coolant temp, actual engine temperature ie. rocker covers, or engine block etc.

[R31Nismoid]

^ agreed.

Without the actual temp - who says it is getting too hot?

Just because it feels hot means little.

[EFI Performance]

If its a stainless exhaust manifold, good luck keeping the heat out.

Gauge the engine temp via the ecu, see what it is reading, watch as it heats up, fans come on and if temp movement decreases.

Another thing, is it too lean???? AFR?

[Deathwish]

Again thanks for all your comments guys. Ok then, i'll try and answer as many questions as i can.

1. Its used 99% on the road but gets really used lol.

2. Its running on a Greddy/Trust Topmount stainless steel manifold.

3. Dont know the actual temps as i dont have any sensors measuring it.

4. I just go by how hand hot the actual inlet plenum and intercooling piping gets.

5. The temp gauge in the dash doesn't show it going over half way so its not overheating as such but just want to get the overall temp down as it cant be doing much good for power and engine wear.

Thanks for all your input, it is much appreciated. Thwish

[The Dan]

Again thanks for all your comments guys. Ok then, i'll try and answer as many questions as i can.

1. Its used 99% on the road but gets really used lol.

2. Its running on a Greddy/Trust Topmount stainless steel manifold.

3. Dont know the actual temps as i dont have any sensors measuring it.

4. I just go by how hand hot the actual inlet plenum and intercooling piping gets.

5. The temp gauge in the dash doesn't show it going over half way so its not overheating as such but just want to get the overall temp down as it cant be doing much good for power and engine wear.

Thanks for all your input, it is much appreciated. Thwish

Point 3 needs to be covered. How do you know it's hotter than NORMAL, unless you know that actual temperature.

The fact is, even a standard RB engine is usually too hot to touch anywhere once it's been for a 10 minute drive. I'm guessing yours is the same, but if you can take a temp reading with a laser pointer or temp gauge on a multimeter, then I will be able to tell you if it's normal or not.

[Craved]

Ceramic coating the inside and outside of the manifold will help on that side

[mad082]

why not put a temp sensor in the intercooler piping just after the turbo but before the intercooler and another one after the intercooler just before the plenum to see what the actual intake temp is and if it is affecting how the intercooler is doing it's job. if you really wanted you could have 2 on the cold side of the cooler, 1 just after the intercooler and one in the plenum to see if it is having any effect. but i would doubt it is having much of an effect as the air is passing pretty quick through the plenum and piping, but if it is causing the intercooler to heat up dramatically then you will be losing power.