Turbo Bag Or Heat Shield

[Roy]

u can raise the back of the bonnet up a bit if u want.

take off bonnet and put some washers on em to act like spacers and raise is 5-10mm doesnt look too different and dramatically realeses heat from the RB26 lol. i would put a shield around ur ABS actuators and a turbo bag. and shield ur exhast.

The that will work, but it wont let hot air flow out...well at least i dont think it will. Due to the pressure differential between the base of the windscreen and engine bay, air is actually nore likely to be siucked into the engien bay...ever seen the scoops on the Walkinshaw commodore, cold air intakes on MX-5s etc etc?

[lwells]

whats these racepace ones worth? might give em a call tommorow, does anyone have a contact number and dont forget the state phone number first as im unsure which state they are in.

Please post up the details if/when you get them. I am in a similar situtation trying to decide which heat insulation method/s is best, though sadly I only have piddly low mounts to worry about

[Craved]

The that will work, but it wont let hot air flow out...well at least i dont think it will. Due to the pressure differential between the base of the windscreen and engine bay, air is actually nore likely to be siucked into the engien bay...ever seen the scoops on the Walkinshaw commodore, cold air intakes on MX-5s etc etc?

im with you Roy, lifting th rear does indeed draw air INTO the engine bay, but it would flow down past the turbo and dump so would indeed work..

main examples are your interior fan vent below the windscreen, also VK group A.

best way is to vent the bonnet similar to the Nur spec r34's, that design actually draws are out of the bonnet area.

[nizmokid]

how about fitting a air duct (pipe) from the front of the car to face the rear of the turbo to keep it cool?....seen it done on a few drift and drag cars in japan......poor mans cooling!!!! .........might work though?

[Tangles]

WHERE can I get a turbo bag?

How much, etc etc?

[INASNT]

how about fitting a air duct (pipe) from the front of the car to face the rear of the turbo to keep it cool?....seen it done on a few drift and drag cars in japan......poor mans cooling!!!! .........might work though?

Now ur trying to push shit uphill!!

[markimak]

guess raising the rear of the bonnet might create a vaccum and suck air down.. it will work though. so do it.

still dont think rain will dramatically cool the turbo down. its not gonna be a torrent anyway. if anything it would be droplets/mist

[caminperth]

Either way, shield or bag, it's going to be the lesser of two evils - you'll have to decide which one though.

Shield - better cooling of the turbo, though hotter underbonnet temps and therefore associated damage to the surrounding objects.

Bag - cooler underbonnet temps, the ability to 'touch' the bag after some hard driving, but heak soak into the bearings when shut down due to the trapped heat and no oil/coolant flow.

[rev210]

Either way, shield or bag, it's going to be the lesser of two evils - you'll have to decide which one though.

Shield - better cooling of the turbo, though hotter underbonnet temps and therefore associated damage to the surrounding objects.

Bag - cooler underbonnet temps, the ability to 'touch' the bag after some hard driving, but heak soak into the bearings when shut down due to the trapped heat and no oil/coolant flow.

Dude,

who turns their engine off straight after flogging it? A few minutes of cool down as per any hard driven turbo will see the temps drop enough to keep things alive. Add this to the fact that I have never had any experience or have even heard of turbo bearings dead as a result of a turbo beanie.

[caminperth]

Dude, how's it going?

Insulating the turbo with a bag will hold more heat in it than it normally would, but would stop heat output to the engine bay. As to how much heat - I'm not sure..

I'm definitely not saying a bag will ruin bearings or that a shield will set fire to everything in the engine bay - just that both have pros and cons.

[BOZ22N]

Correct me if I am wrong but are u guys saying that raising the rear of the bonnet will suck air down into the engine bay? hahahaha

It creates a vacuum or a venturi affect, sucking hot air out of under the bonnet.

I reckon raise or get a vented carbon bonnet and put bags around your abs, and p steer reservoir and ceramic coat your exh manifold then just put a heat shield around your turbs.

Just my thought,

Correct me if I am wrong but are u guys saying that raising the rear of the bonnet will suck air down into the engine bay? hahahaha

It creates a vacuum or a venturi affect, sucking hot air out of under the bonnet.

I reckon raise or get a vented carbon bonnet and put bags around your abs, and p steer reservoir and ceramic coat your exh manifold then just put a heat shield around your turbs.

Just my thought,

[Roy]

Correct me if I am wrong but are u guys saying that raising the rear of the bonnet will suck air down into the engine bay? hahahaha

It creates a vacuum or a venturi affect, sucking hot air out of under the bonnet.

I reckon raise or get a vented carbon bonnet and put bags around your abs, and p steer reservoir and ceramic coat your exh manifold then just put a heat shield around your turbs.

Just my thought,

Doesnt it come back to pressure, and where there is a high pressure area, that air will want to move to a lower pressure area. I understand the base of the windscreen to be a high pressure area. Cars liek the MX5 etc drill big holes in the window sill/firewall and put their cold air intakes there as the high pressure area gives them an inlet charge effect.

Dick Johsnon Racing got in trouble back in 94/95 when during tech inspection it was revealed that the firewalll had some opening to the grill at the base of the windsreen, and at speed the low/high pressure gavce themn more hp as the cars airbox was havign air forced into it.

As posted the VK Brocks bonnet spoiler, as was the A9X etc all had the opening facign backwards near the base of the windscreen....i understand this is all to do with differential pressures and the fact that higher pressure air wanst to move to lower pressure areas....

[caminperth]

As posted the VK Brocks bonnet spoiler, as was the A9X etc all had the opening facign backwards near the base of the windscreen....i understand this is all to do with differential pressures and the fact that higher pressure air wanst to move to lower pressure areas....

The ugly (or beautiful as I see it) Wilkinsaw VL had the same arrangement for the induction - rear facing scoop.

[Roy]

The ugly (or beautiful as I see it) Wilkinsaw VL had the same arrangement for the induction - rear facing scoop.

I love the Walkie...so as i see it lifting the bonnet may help get some cooler air in the stinking hot underside of the bonnet, but i dont think its the greatest fix, and not one i would expect the original poster would be happy with considering the spend on the car

[BOZ22N]

very tyred, i am trying to find a proper deffinition for you, if i am right? all i can find at the moment is this

Bernoulli's principle applies to any fluid, and since air is a fluid, it applies to air. The camber of an airfoil causes an increase in the velocity of the air passing over the airfoil.

This results in a decrease in the pressure in the stream of air moving over the airfoil. This decrease in pressure on the top of the airfoil causes lift.

so as i understad it the shape of a cars front end looking side on is sort of like a foil, long and curved on the top and short and relativley straight on the bottom. so therefore the top of the bonett we have a low (fast moving air) and under it we have a high (slower moving air) there for causing a pressure differential and air flow outward from the engine bay.

i will try and think about it tomorrow at work, mybe i am wrong?

cheers,

[Roy]

very tyred, i am trying to find a proper deffinition for you, if i am right? all i can find at the moment is this

so as i understad it the shape of a cars front end looking side on is sort of like a foil, long and curved on the top and short and relativley straight on the bottom. so therefore the top of the bonett we have a low (fast moving air) and under it we have a high (slower moving air) there for causing a pressure differential and air flow outward from the engine bay.

i will try and think about it tomorrow at work, mybe i am wrong?

cheers,

LOL...yeh Fluid Mechanics

You are right, but consider what happens to the airflow as it hits the grille/headlights, then the base of the windscreen, the airflwo becomes detached and its basically a mass of turbulence...so its a bit more complicated then it first appears , and a foil is not an accurate model of what is happening with airflow.

But this is gettign away fromt eh point of the thread, it will help under bonnet temps...full stop

Are there better ways to control the temps? No doubt, keep the temp in the exhuast gases

[WetGTR]

Hi Brad!

Racepace contact details are as follows:

Talk to Ben on (03) 9762 9421.

Hmmm Benno's the man

[INASNT]

very tyred, i am trying to find a proper deffinition for you, if i am right? all i can find at the moment is this

so as i understad it the shape of a cars front end looking side on is sort of like a foil, long and curved on the top and short and relativley straight on the bottom. so therefore the top of the bonett we have a low (fast moving air) and under it we have a high (slower moving air) there for causing a pressure differential and air flow outward from the engine bay.

i will try and think about it tomorrow at work, mybe i am wrong?

cheers,

LOL quoting your uni text books????

I actually use alot of fluid dynamics for work with hydro turbines and the rear off the bonnet will not pull out hot air as much as a text book would make you believe.

[BOZ22N]

LOL quoting your uni text books????

I actually use alot of fluid dynamics for work with hydro turbines and the rear off the bonnet will not pull out hot air as much as a text book would make you believe.

Sorry mate no uni degree here I am a mechanic. lol

Just interested in the "why" factor so I look into things a bit more than I probably should.

Good luck with your choice cruise liner, which ever way you go it will still work and your engine still rocks my world.

Ryan

[CruiseLiner]

Sorry mate no uni degree here I am a mechanic. lol

Just interested in the "why" factor so I look into things a bit more than I probably should.

Good luck with your choice cruise liner, which ever way you go it will still work and your engine still rocks my world.

Ryan

cheers mate for the support, ive been reading on the net in general about the turbo bags and especially on the aus rx7 forums they have about 5 of them saying they have had manifolds cracking within 6 months and other probs, etc and thats shop owners saying that not just normal users. they all highly reccomend to keep the heat off everything else by using metal shields on the bits u want cool, not on the turbo itself.

interesting reading on some other forums...

cheers

Brad