Intake routing ls swap....How did you get cold air? (1 Viewer)

[cseitz]

I recently installed a mild cam in my 5.3, and had it tuned. After going over the results with the tuning wizard (LS pros in Sacramento) the window at which my engine runs best is in the 70-110 degree range for intake air temp. I can slip out of that range rather quick and performance just seems to fall off. So, I'm trying to figure out a better way to keep my intake as cool as possible. Anyone have a clever way of routing your intake to get cold air? Just curious what others have done.

 

[mr jits]

I recently installed a mild cam in my 5.3, and had it tuned. After going over the results with the tuning wizard (LS pros in Sacramento) the window at which my engine runs best is in the 70-110 degree range for intake air temp. I can slip out of that range rather quick and performance just seems to fall off. So, I'm trying to figure out a better way to keep my intake as cool as possible. Anyone have a clever way of routing your intake to get cold air? Just curious what others have done.

It gets pretty hot underhood in an LS swapped 40. I would think your best bet (although ugly) would be a snorkle.

 

[cseitz]

It gets pretty hot underhood in an LS swapped 40. I would think your best bet (although ugly) would be a snorkle.

I just cant bring myself to put a snorkel on my cruiser. That is what my tuner mentioned as well, I thought he was kidding. I have been trying to come up with some sort of an intake box to try and keep my air cleaner separated from engine bay heat.

 

[afraptor22]

The way the front end tapers in there is no space on the sides of the radiator to pull in fresh air. With the front intake LS intake you have to do a 180 to go back and pull in air from somewhere near the cowl. All that tubing absorbs heat, even with my snorkel I get high IAT. You could get crazy and flip the intake backwards and then go 90 up. You’ll have very little room for a MAF though.

 

[cseitz]

The way the front end tapers in there is no space on the sides of the radiator to pull in fresh air. With the front intake LS intake you have to do a 180 to go back and pull in air from somewhere near the cowl. All that tubing absorbs heat, even with my snorkel I get high IAT. You could get crazy and flip the intake backwards and then go 90 up. You’ll have very little room for a MAF though.

I've thought about that as well. My aluminum intake ducting heat sinks really bad. I've got some exhaust heat shield and was thinking about wrapping it.

 

[afraptor22]

I've thought about that as well. My aluminum intake ducting heat sinks really bad. I've got some exhaust heat shield and was thinking about wrapping it.

Heres an old picture of my engine bay and why it's so cramped with that large filter cylinder. Making some heat shields or covering them with heat shield might help. Something I need to do when I finally stop putting different motors in the thing.

20200104_102413.jpg

• afraptor22
• May 3, 2020

 

[afraptor22]

20200503_084438.jpg

• afraptor22
• May 3, 2020

 

[FF LC FREAK]

I built a box for my filter. It is only open to the front - beside the radiator and over the steering gear. The lid is removeable so I can get at the filter. It significantly dropped my IAT for the most part. But sitting in traffic/on the trail on a hot day, the temps start rising. However, before I built the box, with just an open element inside the engine bay, I saw temps hitting 165*. Now the hottest I've seen is 130*. Not perfect, but way better than it was. It is also much slower to raise. I think the only way to drop more from there is to add a snorkel. I just didn't want to do that.

Here's a couple of pics. This was my original attempt at building it. I kind of added to it as I went along. My plan is to make a much nicer looking box at some point, but I haven't gotten around to it yet. In other words, ignore the crappy welds and metal work.

 

[cseitz]

Heres an old picture of my engine bay and why it's so cramped with that large filter cylinder. Making some heat shields or covering them with heat shield might help. Something I need to do when I finally stop putting different motors in the thing.

20200104_102413.jpg

• afraptor22
• May 3, 2020

That's a good way to do it. You got me beat for room, my cruiser has coilovers up front and the hoops and engine brace also take up some good room.

 

[cseitz]

I built a box for my filter. It is only open to the front - beside the radiator and over the steering gear. The lid is removeable so I can get at the filter. It significantly dropped my IAT for the most part. But sitting in traffic/on the trail on a hot day, the temps start rising. However, before I built the box, with just an open element inside the engine bay, I saw temps hitting 165*. Now the hottest I've seen is 130*. Not perfect, but way better than it was. It is also much slower to raise. I think the only way to drop more from there is to add a snorkel. I just didn't want to do that.

Here's a couple of pics. This was my original attempt at building it. I kind of added to it as I went along. My plan is to make a much nicer looking box at some point, but I haven't gotten around to it yet. In other words, ignore the crappy welds and metal work.

That's the route I'll need to go. How did you come over the alternator with the ducting? Mine goes to the passenger side because of the alternator

 

[FF LC FREAK]

This was my original routing. Just up and over the alternator.

In an effort to get cooler air, I put in this set up. But the filter was too restrictive, and I kept getting DTCs. But this is the current routing, but with the bigger filter and box that I posted before. I did wrap the pipe with HVAC insulation from Home Depot. That actually did help.

 

[cseitz]

This was my original routing. Just up and over the alternator.

In an effort to get cooler air, I put in this set up. But the filter was too restrictive, and I kept getting DTCs. But this is the current routing, but with the bigger filter and box that I posted before. I did wrap the pipe with HVAC insulation from Home Depot. That actually did help.

I see. I think I might have mounted my engine a little higher than yours. Also is the a 105A alternator, I went 140 and the frame size looks a little bigger. I'd love to sweep my intake over to the driver side, since it is opposite my battery. Maybe I can get an oval pipe that will clearance the hood better. I think you have the right idea on the intake box though. Just ditch the headlight on the side like some of the import cars do and you'll be set.

 

[FF LC FREAK]

Yeah, you are definitely lacking space in your engine bay with the shock hoops and cross brace. Good luck!

 

[cseitz]

Yeah, you are definitely lacking space in your engine bay with the shock hoops and cross brace. Good luck!

Yeah its tight. I ordered a Cobra intake elbow which is very compact to come off the throttle body, and try and make my way over to the drive side engine bay. Ive been looking at Craigslist and FB market place too see about swooping up a used intake box that I can make work. Ive thought about building something out of aluminum but if I can get something out of abs I think it will help with heat better. I'll post pics as it develops.

 

[mano002]

I don't have an LS, but I used one of these on another build, and I liked the options for plumbing the snorkel off any side. Universal Air Box

 

[cseitz]

I don't have an LS, but I used one of these on another build, and I liked the options for plumbing the snorkel off any side. Universal Air Box

Yeah that's pretty much what I am leaning towards. There is a handful of similar used ones that pop up.

 

[peesalot]

I have your exact situation on my ls swaped 40. Save my heater fan is gone. Lay the optima sideways and or shorten the battery tray a bit, run an intake tube over batt, attach filter just past batt, it will come right to the heater fan, make a heat shield, so it isolates the filter and the louvers in the hood. I used roof flashing from ace and rivets, the prebent 90's on the flashings comes in handy, used some weather strip on edges to seal at hood, stuck heat shield to outside. Mounted on top of fender well and on the firewall rib next to heater fan.

 

[cseitz]

I have your exact situation on my ls swaped 40. Save my heater fan is gone. Lay the optima sideways and or shorten the battery tray a bit, run an intake tube over batt, attach filter just past batt, it will come right to the heater fan, make a heat shield, so it isolates the filter and the louvers in the hood. I used roof flashing from ace and rivets, the prebent 90's on the flashings comes in handy, used some weather strip on edges to seal at hood, stuck heat shield to outside. Mounted on top of fender well and on the firewall rib next to heater fan.

You lost me, any pics? I pulled my battery to swap it over to the drivers side. I could get over my alternator without hitting the hood, so I have to stay on the pass side.

 

[spotcruiser]

I have a 1st Gen 5.7l Vortec, so I don't really have the same input air temperature problem that you do, but I wanted to keep the filter dry and free of crap. I didn't find any commercial air boxes that would fit in the available space, so I welded up a 16 gauge steel housing for it. The filter housing is open to the front and outboard side, but could very easily have been open to outside air through louvres or a snorkel for cooler air. You could do something similar.

 

[peesalot]

I'm talking about the passenger side. If battery is gone then extend intake tubing toward firewall until tip of air cleaner is right at the heater blower. Create an airbox using the stock hood louver as the fresh air inlet.