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Nothing fancy, just a Hellcat lower intake box, aFe headlight duct, intake tube w/o a silencer, and oil catch can (by Speedlogix). Attached some before & after pics, nothing flashy, but that was kinda the point, keep it sleeper-ish.

Had a friend help, took about an hour. Hardest parts were getting hoses on the existing nozzles (even with lube) and setting the air box right. We apparently kept setting the air box too low and couldn’t get the top of the air box to go on as it was too close to the coolant tank.

Also, what is that smaller tube connected to the top of the air box for? Noticed there was a diagonal plastic wall in the corner of the air box lid, seems like that would restrict airflow. Wondering if I should get the SRT airbox lid now.

Initial impressions - haven’t driven it too much since but so far it sorta feels like the sound has been subdued a bit to me. Last couple days beforehand I’d been driving quite a bit in Sport mode with windows down (I’m in AZ), enjoying the sounds. So far, after the mods with maybe two 10min drives, the exhaust note sounds a bit....flatter, like less bassy sound, and bit quieter overall. Was surprising, half tempted to put intake tube w/ silencer back on (think it would sit fine ontop if catch can, just more work to empty it) and see how it sounds. But I’ll give it a few days first, maybe it’s my imagination, I dunno.

On the other hand, the increased throttle response is noticeable. Not “huge” but noticeable to me and makes shift the 6mt a little be easier. I swear each gear goes to a higher speed than before too, before needing to shift, but think I’m crazy there. Probably just driving more spirited than I have before! :)

Hopefully be getting the clutch delay valve deleted next weekend at a friend’s who has a jack, well lift, that can lift this heavy of a car. My little cheap one can’t, ha ha!

Edit: so got a question....on one of my short drives after installing these mods I was at a light and it turned green and the guy in front was just sitting there for way too long. So instead of honking I decided to just rev the engine a little, to get their attention and to test out sound. The gear was in neutral, I had the clutch pushed in, I poked/tapped the gas (aka foot wasn't rest on the pedal, just quick touch, then moved foot away) and it rev'd to about 3k rpm......but instead of just quick "vroom" to 3k rpm and then back down to idle, it "stuck" at 3k rpm for like 2-3 sec while my foot was NOT on the gas pedal, THEN it went back down to idle. It was like the throttle got stuck open or something. It was weird to me, my question (finally!) is could that be a result of anything I installed? Or just a weird fluke? Any areas I should double check?
 

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Nothing fancy, just a Hellcat lower intake box, aFe headlight duct, intake tube w/o a silencer, and oil catch can (by Speedlogix). Attached some before & after pics, nothing flashy, but that was kinda the point, keep it sleeper-ish.

Had a friend help, took about an hour. Hardest parts were getting hoses on the existing nozzles (even with lube) and setting the air box right. We apparently kept setting the air box too low and couldn’t get the top of the air box to go on as it was too close to the coolant tank.

Also, what is that smaller tube connected to the top of the air box for? Noticed there was a diagonal plastic wall in the corner of the air box lid, seems like that would restrict airflow. Wondering if I should get the SRT airbox lid now.

Initial impressions - haven’t driven it too much since but so far it sorta feels like the sound has been subdued a bit to me. Last couple days beforehand I’d been driving quite a bit in Sport mode with windows down (I’m in AZ), enjoying the sounds. So far, after the mods with maybe two 10min drives, the exhaust note sounds a bit....flatter, like less bassy sound, and bit quieter overall. Was surprising, half tempted to put intake tube w/ silencer back on (think it would sit fine ontop if catch can, just more work to empty it) and see how it sounds. But I’ll give it a few days first, maybe it’s my imagination, I dunno.

On the other hand, the increased throttle response is noticeable. Not “huge” but noticeable to me and makes shift the 6mt a little be easier. I swear each gear goes to a higher speed than before too, before needing to shift, but think I’m crazy there. Probably just driving more spirited than I have before! :)

Hopefully be getting the clutch delay valve deleted next weekend at a friend’s who has a jack, well lift, that can lift this heavy of a car. My little cheap one can’t, ha ha!


Very nice. Good job!
 
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Nothing fancy, just a Hellcat lower intake box, aFe headlight duct, intake tube w/o a silencer, and oil catch can (by Speedlogix). Attached some before & after pics, nothing flashy, but that was kinda the point, keep it sleeper-ish.

Had a friend help, took about an hour. Hardest parts were getting hoses on the existing nozzles (even with lube) and setting the air box right. We apparently kept setting the air box too low and couldn’t get the top of the air box to go on as it was too close to the coolant tank.

Also, what is that smaller tube connected to the top of the air box for? Noticed there was a diagonal plastic wall in the corner of the air box lid, seems like that would restrict airflow. Wondering if I should get the SRT airbox lid now.

Initial impressions - haven’t driven it too much since but so far it sorta feels like the sound has been subdued a bit to me. Last couple days beforehand I’d been driving quite a bit in Sport mode with windows down (I’m in AZ), enjoying the sounds. So far, after the mods with maybe two 10min drives, the exhaust note sounds a bit....flatter, like less bassy sound, and bit quieter overall. Was surprising, half tempted to put intake tube w/ silencer back on (think it would sit fine ontop if catch can, just more work to empty it) and see how it sounds. But I’ll give it a few days first, maybe it’s my imagination, I dunno.

On the other hand, the increased throttle response is noticeable. Not “huge” but noticeable to me and makes shift the 6mt a little be easier. I swear each gear goes to a higher speed than before too, before needing to shift, but think I’m crazy there. Probably just driving more spirited than I have before! :)

Hopefully be getting the clutch delay valve deleted next weekend at a friend’s who has a jack, well lift, that can lift this heavy of a car. My little cheap one can’t, ha ha!
Did you take the rubber bushing off the bottom of your factory air box and mount it on the bottom of the Hellcat one? If not that could be why it is not sitting right.

That Small tube is for make up air for the PCV system when the PCV valve is open it draws air in there, when it is closed it pulls oil/blow by through it, they little chamber in the lid it so the air goes through the filter twice before entering you intake tube and throttle body. Don't believe me, check your airfilter after about 9k miles, mine was black with oil in that spot.
 

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Discussion Starter #4
Did you take the rubber bushing off the bottom of your factory air box and mount it on the bottom of the Hellcat one? If not that could be why it is not sitting right.

That Small tube is for make up air for the PCV system when the PCV valve is open it draws air in there, when it is closed it pulls oil/blow by through it, they little chamber in the lid it so the air goes through the filter twice before entering you intake tube and throttle body. Don't believe me, check your airfilter after about 9k miles, mine was black with oil in that spot.
Yeah, I had read people saying it was a bit of a pain to get that little rubber bushing off the bottom and around the screw mount off, but they both popped right off for me. I think what we were doing was pushing it too far into the fender. Like with that rubber bushing on the bottom I don't think it needs to go all the way into the hole till the box touches the fender. Which is basically what we were doing, really pushing it down to make sure it was really firm, which seemed to make it sit too low and so that last tab (further right) on the lid wouldn't go in cause the right side of the lid was right against the coolant tank. I did not put any weather striping foam on that rectangle area on the new hellcat airbox if that matters at all?

I'm noobish, what's PCV stand for and what does the system do? So should I just leave the factory RT airbox lid on it then and not get the SRT one? Actually do the larger engines have that little tube coming off the airbox as well even?

Thanks for the info!
 

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Yeah, I had read people saying it was a bit of a pain to get that little rubber bushing off the bottom and around the screw mount off, but they both popped right off for me. I think what we were doing was pushing it too far into the fender. Like with that rubber bushing on the bottom I don't think it needs to go all the way into the hole till the box touches the fender. Which is basically what we were doing, really pushing it down to make sure it was really firm, which seemed to make it sit too low and so that last tab (further right) on the lid wouldn't go in cause the right side of the lid was right against the coolant tank. I did not put any weather striping foam on that rectangle area on the new hellcat airbox if that matters at all?

I'm noobish, what's PCV stand for and what does the system do? So should I just leave the factory RT airbox lid on it then and not get the SRT one? Actually do the larger engines have that little tube coming off the airbox as well even?

Thanks for the info!
PCV= Positive Crankcase Ventilation. You hooked your catch can up to the PCV valve and then to the manifold. When that PCV opens, oil and vapors are sucked out that side through the catch can, air is pulled in from the small hose connected to the top of the airbox. When the PCV valve closes, under low manifold vacuum situations, Wide Open Throttle, pressure in the crankcase goes out that little hose and through the air cleaner, that little "well" in the corner makes sure it passes through the air cleaner before it enters your intake tube and throttle body. Yes leave the R/T lid on. That is what I did.
 

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Yeah, I had read people saying it was a bit of a pain to get that little rubber bushing off the bottom and around the screw mount off, but they both popped right off for me. I think what we were doing was pushing it too far into the fender. Like with that rubber bushing on the bottom I don't think it needs to go all the way into the hole till the box touches the fender. Which is basically what we were doing, really pushing it down to make sure it was really firm, which seemed to make it sit too low and so that last tab (further right) on the lid wouldn't go in cause the right side of the lid was right against the coolant tank. I did not put any weather striping foam on that rectangle area on the new hellcat airbox if that matters at all?

I'm noobish, what's PCV stand for and what does the system do? So should I just leave the factory RT airbox lid on it then and not get the SRT one? Actually do the larger engines have that little tube coming off the airbox as well even?

Thanks for the info!
Positive Crankcase Ventilation. There used to be material outside of the valve collectors but some federal agency deemed it was yucky or something. So now you collect it in a separate can and dispose of it in a very responsible way...............or something.
 

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Positive Crankcase Ventilation. There used to be material outside of the valve collectors but some federal agency deemed it was yucky or something. So now you collect it in a separate can and dispose of it in a very responsible way...............or something.
Probably should have asked this in the beginning, but I'm guessing when I empty I just poor it into like an empty water bottle and take it to an auto parts store to dipose of? I use to do my own oil changes on one car I owned (which I didn't enjoy, more so cause that car was pos and I hated it in general) and that's how I'd dispose of it's used oil, though it was more than a water bottle's worth!
 

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rev'd to about 3k rpm......but instead of just quick "vroom" to 3k rpm and then back down to idle, it "stuck" at 3k rpm for like 2-3 sec while my foot was NOT on the gas pedal, THEN it went back down to idle. It was like the throttle got stuck open or something. It was weird to me, my question (finally!) is could that be a result of anything I installed? Or just a weird fluke? Any areas I should double check?
There is definitely a little hang time after you rev the engine (usually around 1500-2000rpm)...mine does it for ~1-2 seconds. One of these days I will log RPM, throttle blade position, pedal position to see what is happening.
 

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Probably should have asked this in the beginning, but I'm guessing when I empty I just poor it into like an empty water bottle and take it to an auto parts store to dipose of? I use to do my own oil changes on one car I owned (which I didn't enjoy, more so cause that car was pos and I hated it in general) and that's how I'd dispose of it's used oil, though it was more than a water bottle's worth!


I guess some of us (you) are more responsible than others (me). I put it in an empty plastic pop bottle and put it in the recycle bin. It's all oil based.......I tell myself. Really just a few spoon fulls come out at oil change time. Do it then..... pour it in his thing. Just don't put it back in the car. I saw someone want to do that.
 

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There is definitely a little hang time after you rev the engine (usually around 1500-2000rpm)...mine does it for ~1-2 seconds. One of these days I will log RPM, throttle blade position, pedal position to see what is happening.
Ok, so it's not just me. I thought I had observed similar at higher rpm but for like a split second. This particular time around 3000rpm it was a noticeable hang. Just kinda weird to me as previous manuals I had didn't do that, though to be fair I've only had two other manuals in my life so far, a 2005 V6 Mustang and a 2008 BMW M3. The latter basically acted like an indy car engine, very responsive! (It had 4.0L V8 w/ 414hp and 8400rpm redline).


Just don't put it back in the car
Ha ha! I won't be doing that! After doing my own oil changes on that one car of mine, I've seen what it does to the oil. It goes in a nice transparent golden color, comes out solid black/dark brown, ha ha.
 

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The "oil" in the catch can is really a nasty brew of oil and fuel vapors, known as blow-by, that leak past the piston rings. It is definitely not something that you want back into the engine.
 

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The "oil" in the catch can is really a nasty brew of oil and fuel vapors, known as blow-by, that leak past the piston rings. It is definitely not something that you want back into the engine.

A Greenie on a prior thread wanted to put, "it" back "in". Wasn't comfortable with discarding it at all. LOL!!!! A future Prius owner to be sure!
 

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There is definitely a little hang time after you rev the engine (usually around 1500-2000rpm)...mine does it for ~1-2 seconds. One of these days I will log RPM, throttle blade position, pedal position to see what is happening.
Well, here is a log I just took. As you can see it hangs around 1500rpm for ~2 sec and then finally ramps down to idle at ~1 sec.
 

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Well, here is a log I just took. As you can see it hangs around 1500rpm for ~2 sec and then finally ramps down to idle at ~1 sec.
I....I have no idea how to read this, ha ha! But I'd be curious about any further testing you do! What kind of tool/system do you need to get this data?

Did you remove the silencer intake tube as well? Or is this stock under there? Hellcat intake? I guess I'm curious if it does this stock or if it's cause of one of the mods I/we did.
 

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The green line is RPM and the blue line is the actual throttle blade position (valve in the throttle body). Ignore the purple line for now as I thought it was the accelerator pedal position but apparently it is not. I am not expert but here is how I interpret the log (see attachment for comments). In short, when my foot is off the pedal, the throttle blade does not immediately go to fully closed (i.e. idle) position. Also the engine speed decreases at 3 distinct rates which I am not 100% sure why. I suspect it is a combination of the VVT repositioning the cam, the throttle still being slightly open and the PCM tune. Maybe someone more knowledgeable can chime in and school my monkey arse.

I used a Diablo Trinity (hand held device) to log data. Diablo sells 2 versions of the trinity....one that just monitors PCM functions and one that can modify PCM functions (i.e. allows you to tune the PCM...PCM must be unlocked by Diablo). HP Tuners also makes a version which requires a laptop and targets more advance DIY tuners. I like the diablo because it is a stand alone device and gives me basic tuning capabilities.

I am using a Hell Cat lower intake box and tube and since I have a supercharger (I will stress that the car would hang even when the engine was bone stock...maybe I should log my 5.7 grand cherokee as proof) the intake tube is just a silicone elbow with a hump in it to allow for flexibility.
 

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The green line is RPM and the blue line is the actual throttle blade position (valve in the throttle body). Ignore the purple line for now as I thought it was the accelerator pedal position but apparently it is not. I am not expert but here is how I interpret the log (see attachment for comments). In short, when my foot is off the pedal, the throttle blade does not immediately go to fully closed (i.e. idle) position. Also the engine speed decreases at 3 distinct rates which I am not 100% sure why. I suspect it is a combination of the VVT repositioning the cam, the throttle still being slightly open and the PCM tune. Maybe someone more knowledgeable can chime in and school my monkey arse.

I used a Diablo Trinity (hand held device) to log data. Diablo sells 2 versions of the trinity....one that just monitors PCM functions and one that can modify PCM functions (i.e. allows you to tune the PCM...PCM must be unlocked by Diablo). HP Tuners also makes a version which requires a laptop and targets more advance DIY tuners. I like the diablo because it is a stand alone device and gives me basic tuning capabilities.

I am using a Hell Cat lower intake box and tube and since I have a supercharger (I will stress that the car would hang even when the engine was bone stock...maybe I should log my 5.7 grand cherokee as proof) the intake tube is just a silicone elbow with a hump in it to allow for flexibility.
Ah ok, hmmm that is interesting why it does that.
 

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I love that you're modding your car but didn't you post on another thread that this was a lease? Just wondering why you would go to the trouble and effort to mod it then. Won't you have to reverse all of this mods as well? Are you considering keeping the car as a buyout? Not trying to be a smartas$, just wouldn't want to see you waste your $$ or have issues when you give the car back etc.
 

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I love that you're modding your car but didn't you post on another thread that this was a lease? Just wondering why you would go to the trouble and effort to mod it then. Won't you have to reverse all of this mods as well? Are you considering keeping the car as a buyout? Not trying to be a smartas$, just wouldn't want to see you waste your $$ or have issues when you give the car back etc.
It is a lease and currently have no plans to buy it afterwards. Hoping by the time the lease is up I can afford a Scat Pack, but even if I can't I'd probably want whatever newer tech they put in them then. There's not really any "trouble and effort" I'm only doing simple/easy mods that can be done/undone in an hour or so. I've only spent about $320 on everything here (plus AEM filter and trunk strap), which to me $320 over 3yrs is pretty cheap amount to budget for a little bit more "fun" out of the car. Actually it'll be less as I can sell the parts afterwards as well.

Honestly think a lot of them would go unnoticed at turn in. Oil catch can and non-silencer intake tube would be most noticeable, but I doubt anyone would notice the hellcat air-box unless I pointed it out, and certainly not the clutch delay valve delete. But we'll see if I feel that way when it gets closer, but if I change my mind it won't be more than an hour or two to put everything back and then sell the parts.

Only other thing I may do is a shorter shift stick and custom knob, that's about it really. Tempted by the Barton shift, but the price and install of that, seems a bit much for a lease to me.....but we'll see.
 

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It is a lease and currently have no plans to buy it afterwards. Hoping by the time the lease is up I can afford a Scat Pack, but even if I can't I'd probably want whatever newer tech they put in them then. There's not really any "trouble and effort" I'm only doing simple/easy mods that can be done/undone in an hour or so. I've only spent about $320 on everything here (plus AEM filter and trunk strap), which to me $320 over 3yrs is pretty cheap amount to budget for a little bit more "fun" out of the car. Actually it'll be less as I can sell the parts afterwards as well.

Honestly think a lot of them would go unnoticed at turn in. Oil catch can and non-silencer intake tube would be most noticeable, but I doubt anyone would notice the hellcat air-box unless I pointed it out, and certainly not the clutch delay valve delete. But we'll see if I feel that way when it gets closer, but if I change my mind it won't be more than an hour or two to put everything back and then sell the parts.

Only other thing I may do is a shorter shift stick and custom knob, that's about it really. Tempted by the Barton shift, but the price and install of that, seems a bit much for a lease to me.....but we'll see.

I don't think you will have a problem at the dealership when turning it in. There are no guarantees on anything in life, only after. You are not hurting the car, only upgrading it. Leave it on or take it off.......... I doubt you will have a problem. And if you did.......how bad can it get while looking at another one? Really all depends on the dealer. I plan on buying but I have NO worries. I'll get thanked.
 
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