wow, sounds like you've done some serious work to try and control the heat already. From my understanding, the stock cooling system on the 9-5 isn't too magnificent. If you haven't already, maybe it's time for a more efficient radiator and possibly better fans.

As for the padding on the hood, I would just remove it. That thick wool-like material is there to absorb the engine heat in order to protect the paint on the other side of the hood. All of that excess heat from the engine is just getting trapped and spread out in it with minimal ability to dissipate. Plenty of people on here run their Saabs without it and haven't complained of any paint issues; however due to your overall increased heat production, there's always the chance that you have a different outcome.

 

wow, sounds like you've done some serious work to try and control the heat already. From my understanding, the stock cooling system on the 9-5 isn't too magnificent. If you haven't already, maybe it's time for a more efficient radiator and possibly better fans.

As for the padding on the hood, I would just remove it. That thick wool-like material is there to absorb the engine heat in order to protect the paint on the other side of the hood. All of that excess heat from the engine is just getting trapped and spread out in it with minimal ability to dissipate. Plenty of people on here run their Saabs without it and haven't complained of any paint issues; however due to your overall increased heat production, there's always the chance that you have a different outcome.

I completely forgot to mention, but yes I do have a bigger radiator (d088) and new mishimoto fans. That’s what i’ve been thinking too. People on other forums say to take it off for better heat dissipation, while others say the complete opposite.

 

I doubt removing the padding will do anything much more than make your hood pretty hot.

I assume it's a non-stock turbo? And no heat shield? Because if your radiator fan is melting, there is way too much heat being radiated into the engine compartment.

Does the temp gauge go above the horizontal?

Does it do that when the car is sitting still, when driving down the highway, or what?

 

yeah it’s a GTX3076 top mount turbo. no heat shield, but it does have a blanket wrap on the hot side. There is no heat shield because the turbo is too big.
The heat gauge doesn’t go above the horizontal mark, but the car runs in the range of 210-230 in the city which is too hot for my liking. on the highway I can get it down to 195 but that’s with good conditions. at idle the car sits at about 210-215.

 

yeah that is definitely hot, my 9-5 is tuned but is still sitting in the 83-85°C (~185°F) in the city and at idle. Only during hot n humid PA summer days or when I'm doing an Italian tune up am I seeing anything close to 100°C. I'm not too familiar with the top mount turbos on these cars, but I would reach out to some of the people on the forum who have done it and see what their temperatures are like. They would be of more help.

 

Is this a daily driver, & if not have you considered hood vents? They would tend to have more effect at speed compared to idle but heat soak turbo applications are probably one of the few times they are functional. Along a similar vein, I don't know if removing the weather stripping from the below cowling below the windshiekd/wipers will help evactuate air more efficiently.

Short of that unfortunately I don't think you have much space to work with if you can't even drop a turbo heat shield on. In MR applications I've seen people use a vented hood with exhaust fans to greatly decrease heat soak & IATs, especially at idle but you don't really have that option. Also, removing the padding will increase the temp of the actual hood & probably cause paint issues.

I know you're referring to operating temps but if you're melting radiator fans what kind of IATs are you seeing at idle & at speed? I hope the heat soak was accounted for in your tune.

 

Is this a daily driver, & if not have you considered hood vents? They would tend to have more effect at speed compared to idle but heat soak turbo applications are probably one of the few times they are functional. Along a similar vein, I don't know if removing the weather stripping from the below cowling below the windshiekd/wipers will help evactuate air more efficiently.

Short of that unfortunately I don't think you have much space to work with if you can't even drop a turbo heat shield on. In MR applications I've seen people use a vented hood with exhaust fans to greatly decrease heat soak & IATs, especially at idle but you don't really have that option. Also, removing the padding will increase the temp of the actual hood & probably cause paint issues.

I know you're referring to operating temps but if you're melting radiator fans what kind of IATs are you seeing at idle & at speed? I hope the heat soak was accounted for in your tune.

This is a daily driver, and I actually have the car tuned pretty tame (about 300whp) so that I don’t operate extremely hot.

As to the discussion on hood vents, I’m trying to stray away from that as I am trying to keep the vehicle looking as stock as possible from the outside. If worse comes to worse, I would install the vents.

I didn’t record my IAT temps after install of the turbo, but I would assume they are not too high due to the fact that I have majority of the intake system wrapped in gold tape to prevent heat soak.

 

Bob might be onto something there. Hood vents would probably help. Ya got these kinds..

OR..for the real dramatic..

 

Gotta find one that suits the saab ha! can’t be caught using tacky ones ! Just messin with ya

 

Hello all,
Just finished up my big turbo build on the saab and noticed that the temps under the hood are higher then I wanted. Its getting so hot that the coolant temp is heating up and not really able to cool down. Its also getting so hot that my fan melted!!

My main question has to do with the padding on the hood of the car. I see most people remove it completely but I did not. I only cut out a small section above the hood so that the turbo doenst accidentally catch it on fire.

Would I benefit from removing it completely? Is the padding holding in heat and not allowing it to dissipate properly?

Right now the manifold, turbo hot side, and downpipe are cermamic coated, heat wrapped, and the turbo has a blanket. The hood above the turbo also has gold reflective tape on it as well.

If you have any extra tips on how to keep the temps down, let me hear em

Thanks in advance!

Only thing I could think of is something similar to this guy in CO. Now it’s for stock mount turbo but something similar with a small fab and ducting for fresh air? Do you have photos of the current set up?

Sent from my iPhone using Tapatalk

 

Only thing I could think of is something similar to this guy in CO. Now it’s for stock mount turbo but something similar with a small fab and ducting for fresh air? Do you have photos of the current set up?

Sent from my iPhone using Tapatalk

I actually contacted him in hopes of having some sort of aluminum radiator shroud made, but he never got back to me and left me hanging. I had cash in hand ready but that didn’t seem to entice him :/ I would love to get something like that fabbed up so that it could shield more of the vital complements. Hopefully I can get his attention with this post!

 

Removing the insulation just lets the hood get hotter, but it's not really designed to dissipate heat. You would have to paint it flat black (so it's a blackbody radiator) and put heat sinks on top of the hood to provide a better cooling area. That would let it reject heat a bit better, but still not that great.

Hood vents would make a lot more sense, as they would actually exhaust hot air. Note, this might make it really hot in the car, because that hot air wold get sucked into the air intake for the HVAC.

I suspect that the best way to deal with the temperature is to have the fans running permanently. Saab's programming for the fans wouldn't take into account the extra radiated heat from the bigger and unshielded turbocharger. So the engine might be at a reasonable temperature, but everything else in the front of the engine compartment is way hotter due to a possibly glowing-red-hot lump of iron sititng in the middle there.

 

I actually do have fans running constantly. I ditched the oem fans for a single 12” mishimoto fans for a total of 1150 cfm. I know 4cyls need around that range for the engine to run properly, but I considered the fact that this isn’t a “normal” 4cyl so i’m in the process of adding another fan in front of the a/c condensor that will act as a push fan so that the rad fan can pull in more air.

I fear that the material of the mishimoto fan may be a weakness as well because it is made of a pretty cheap/thin plastic. Holding a lighter to it for seconds causes it to melt whereas the oem fan doesn’t begin to melt until 30-40 seconds.

Of course that is a scientific test at all, but it’s enough to show the quality of the plastic used.

 

make a heat shield for the turbo. use the correct material Design Engineering, Inc lots of stuff, the stainless sandwich sheets and the blankets with eyelets are very good. DEI sell installation fastener kits also.

putting a big *** turbo is great on paper but you have to do the work to finish the job and you didnt, so you are paying the price for that,. Hood vents are a good idea but hard to do right. Around 8 inches in from the hood sides half way back from the front. Stay away from anything at the base of the windshield, and 12 inches forward, its a negative pressure area and the air flow actually turns back at that point, which is why there are grilles there below the wiper posts for intake into the HVAC system.

Dont remove the rear hood seal nor the front hood seal.I would leave the blanket also. They work .But your unshielded big *** turbo is roasting everything....fix it.

 

make a heat shield for the turbo. use the correct material Design Engineering, Inc lots of stuff, the stainless sandwich sheets and the blankets with eyelets are very good. DEI sell installation fastener kits also.

putting a big *** turbo is great on paper but you have to do the work to finish the job and you didnt, so you are paying the price for that,. Hood vents are a good idea but hard to do right. Around 8 inches in from the hood sides half way back from the front. Stay away from anything at the base of the windshield, and 12 inches forward, its a negative pressure area and the air flow actually turns back at that point, which is why there are grilles there below the wiper posts for intake into the HVAC system.

Dont remove the rear hood seal nor the front hood seal.I would leave the blanket also. They work .But your unshielded big *** turbo is roasting everything....fix it.

So I just sent the manifold, downpipe and turbo hot side to Jet-Hot to get coated in their Ultra Extreme coating.

The good thing about this coating is that it allows for the use of heat wrap on top of the coating without damaging the ceramic coat. So on top of that coating, I plan to heat wrap everything with DI wrap.

To top things off, and I would like some advice to how beneficial this will be, but I also plan to wrap the manifold in a custom heat wrap blanket.

I already spoke with the company, exchanged dimensions, and the blanket will fit the current manifold I currently have.

Would that even me THAT beneficial? I would think that it has to be to some degree right? I know i’m replying to qwik directly, but input from others would be nice