Hello all.
So, where is the safe place to mount HSV under the hood? place where there is less heat stress to HSV?
thanks.

 

I had initially thought the cowl would be good after seeing Alex's install.....I'm an SRT-4 owner.

I have done a couple of installs of the different Aquamist kits on my car that included the install of the HSV. Because of the way I was injecting at the IC exit and in the cold side pipe my HSV has been down low and in front where theres been good airflow. My latest install which is the HFS-5 which will be port injection I made a bracket and mounted the valve and the flow sensor up high and near the R/S strut tower.

IMO, After reviewing (just thinking after reading post's and talking to Richard and remembering the failures that have occurred over the past couple of years ) I think it comes down to air flow. IMO airflow is the most important thing to consider out side of the obvious = do not put near exhaust components.

I think that in the back of the engine compartment in the EVO near the cowl, heat is getting trapped. Even though the turbo is up front it would at first seem its a great spot but its seems that it isn't.

From my memory of an EVO engine compartment, look at a spot nearer to the L/S strut tower, its not far from your injection points and I think theres might be some airflow there.

Heres an image of mine, Richard has posted an image of another setup in another thread.


Maybe some EVO owners should post images up of some mock-ups (no need for fully installed) and let the community see some ideas so that we can come up with a common consensus on the best spot.

 

How about on the side of the fuse box cover under the hood on the driver's side -- the side of the cover closest to the side of the car? That's where I'm considering relocating my HSV and flow sensor. Sorry, I don't have a picture.

 

I am currently away at school but when I come home for thanksgiving break I am going to thoroughly examine the engine bay and find a location with good airflow and easy mounting.

Jack - does aquamist offer a 6mm inline quick adapter or do you only have 4mm adapters? I am just thinking that if I move my HSV and flowsensor, will I need to run a new line from the pump or can I simply add extra length with a quick disconnect adapter.

 

another thing to consider is underhood temperatures when you are either stuck in traffic or shut the car down and have almost zero air flow. In this case, the lower you can mount it the better. Heat rises, and with no airflow, the area close to the hood of the car is going to get very hot. I found this out the hard way.

 

At least the vent in the hood helps a little. When parked with engine cooling, that is where 90% of the heat will try and exit (heat like air follows the path of least resistance). Has anyone tried to mount the HSV lower in the engine compartment, and away from the rising heat? There may be better airflow there as well. I will look around this weekend and see if I can come up with an alternative mounting location too.

 

mine is just inside of the firewall. not much heat inside of the car

 

I agree with the concerns of when the car stops moving. Even in normal driving, I've seen 130F at the MAF sensor when the car sits at a red light on a 90 degree day. That's especially a concern in an autocross situation where you run hard for a minute, then come back into line a few minutes later with the car stopped and the hood closed. At least at the track you can pop the hood when you come off the track.

Also, I agree that air flow is not necessarily a good thing if it's hot air flowing from the exhaust/turbo area. I think that's the problem with the cowl location. As far as putting the HSV inside the car, that would work okay so long as the line from the HSV to the nozzle isn't too long. Otherwise, you'll have an overrun condition when you lift that is analogous to what happens with a typical pump speed system without any sort of valve mechanism.

 

I have mine mounted to a bracket that's bolted about 1/2 way down the firewall (outside the car) at about the centerline of the car. There should be a chimney effect of cool air rising in that area when the car is parked.

 

i'm not so sure that the overrun condition will happen with a valve operated nozzle. sure, with a pump speed system, the pump is going to slow down before it stops, thus you'll get some excess meth flowing through the nozzle as it turns down. but with a valve system, you cut the flow off immediately regardless of the length of tube between the nozzle and the HSV. of course if the nozzle is mounted lower then the HSV, you'll get gravity feed of any fluid in th eline, but that applies to a short line as well. the best solution would be to have the HSV mounted lower then the nozzle and pointed up so as to no allow the fluid in the line to drain down the nozzle.

 

Yes I do have 6mm quick connects. when your back from school let me know, we can hook up so I can get that MAC valve as well.

 

Hmm...now that I think about it I think the issue is probably determined by whether the fluid between the nozzle and the HSV would be trapped due to air not being able to enter the line between the HSV and the nozzle (same effect as holding your finger over the end of a straw with fluid in the tube). In any case, I would think that engine vacuum (off boost) would be more of a factor than gravity?

 

I know it may not be right for all but another location may be inside a factory air box. or where the air box pickups cool air.

In the previous installs my HSV was low and to the front. I think length of line after the flow sensor is OK if it's not past 3 feet maybe a little more.

Someone should post/link some under the hood images in this thread for discussion purposes and a couple of images of the cowl area near the wiper arms and motor as well.

I'm leaning towards a low spot in the rear where theres under the car airflow, near an inner apron that has some airflow, or the cowl.

In the worse case a thermal heat tube from a mid seventies carbed car could be used like a brake duct. Maybe mount the HSV inside of it near one end and the other end near some cooler airflow......if its the reflective kind it may also help shield it from heat. This stuff is cheap at the typical autoparts store.

Something like this
its called many things, but at Rock Auto under 75 Chevy truck, "Fuel/Air" its called "Fuel Pre-Heater Hose". Basically its a pipe that connects a heat shield on an exhaust manifold to a air cleaner assembly = allows for hot air to the carb to speed warm-up when cold. Theres a black cardboard type and an aluminum foil type, its pretty cheap and easy to work with.

 

here's my mounting location on the firewall. Simple aluminum strip that the HSV and flow sensor are mounted to, which is then bolted to a stud sticking out of the firewall.

 

how about heat shield with thermotec taped inside the heat shiled?? i will post up some pics ofr the heat shield that zzomabe custom made for him and me.