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Engine Forge Intake and BOV

3DoorMadness

Member
Feb 3, 2019
39
60
18
Canada
Yes I spent way too much money for this.

I will upload pictures later but this is all I have. I put it on around 2 weeks ago and haven’t ran into any heat soaking issues yet as temps here in Canada haven’t ran above 15 degrees celsius. Will definitely need a heat shield. My N also has a Forge BOV and JB4 if you were wondering. (credits to @1FastStagea who has been helping me along the way as I’m new to the tuning world )

Here’s a quick little crappy video.

I looked into the flutter but was told I shouldn’t worry as long as it is not fluttering while spooling (which it doesn’t)

 
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I would love to see how it changes once temps get higher up there. I'm in Florida so it's usually around 30~C+ damn near all year round here and have been wondering how to go about a new intake for my climate. If anyone has any suggestions for an intake with insanely hot temps all year round I'd love to know how to deal with that. I mean any cold air intake should be better than stock even in hot climates?
 
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I would love to see how it changes once temps get higher up there. I'm in Florida so it's usually around 30~C+ damn near all year round here and have been wondering how to go about a new intake for my climate. If anyone has any suggestions for an intake with insanely hot temps all year round I'd love to know how to deal with that. I mean any cold air intake should be better than stock even in hot climates?

I’ll let you know as soon as it hits 30 degrees here in Canada.
 
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Another question, do you keep your JB4 bolted to the fuse box? I was wondering when/if I remove the air box where to put it as the air box was the only place that didn't need to be secured.
 
Another question, do you keep your JB4 bolted to the fuse box? I was wondering when/if I remove the air box where to put it as the air box was the only place that didn't need to be secured.

I use Velcro tape. Haven’t had a problem with it coming off. On an additional note, I’ve been running JB4 since 500KM and I am at 6000KM now. No issues other than rough cold starts (actually didn’t start once and misfired) but I suspect this to be due to the cold temperatures here in Canada and the spark plugs I am using. It’s only on the first start of the day after a cold night so I am not too worried about it. Other than that, it’s been perfect!
 
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I have a question regarding the JB4 box. Did you manage to check horsepower improvement ? There is a statement on the brand side saying: "Power gains of up to 100hp and 100tq to the wheels on a stock vehicle", but it sounds totally unreal to me.
 
I have a question regarding the JB4 box. Did you manage to check horsepower improvement ? There is a statement on the brand side saying: "Power gains of up to 100hp and 100tq to the wheels on a stock vehicle", but it sounds totally unreal to me.

Search around the forums. RPM 8300 has been doing the testing with the JB4 and posting his dyno results. 100hp increase isn't that far fetched just not on stock parts or pump fuel. Plus you have to keep in mind those numbers are really for the Stinger GT so it's not really even the same engine it just so happens to work with the 2.0 Stinger which is the same as the N.
 
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I use Velcro tape. Haven’t had a problem with it coming off. On an additional note, I’ve been running JB4 since 500KM and I am at 6000KM now. No issues other than rough cold starts (actually didn’t start once and misfired) but I suspect this to be due to the cold temperatures here in Canada and the spark plugs I am using. It’s only on the first start of the day after a cold night so I am not too worried about it. Other than that, it’s been perfect!

Oh good I was really hoping that drilling wasn't necessary as I'd rather not have holes in the fuse box. I might grab some real strong velcro and try that out. I actually emailed Forge last night and asked if they had tested the i30N intake with the VN and they said that they had and it worked as well as they hoped so next week they are going to put it up for sale under the Veloster N section after they finalize fitment.
 
Oh good I was really hoping that drilling wasn't necessary as I'd rather not have holes in the fuse box. I might grab some real strong velcro and try that out. I actually emailed Forge last night and asked if they had tested the i30N intake with the VN and they said that they had and it worked as well as they hoped so next week they are going to put it up for sale under the Veloster N section after they finalize fitment.

The i30N intake fit perfectly on my VN, I wonder what changes they would actually be making (if any). Both the BOV and intake are from Forge and made for the “i30N”.
 
I’ll let you know as soon as it hits 30 degrees here in Canada.

Any update on those intake temps? I think we're pretty close to actually having some options for the intake and I can't decided if I want to go for a closed box or an open intake.
 
Any update on those intake temps? I think we're pretty close to actually having some options for the intake and I can't decided if I want to go for a closed box or an open intake.

I am not an expert by any stretch, but I imagine there wont be much difference between a closed box or an open intake. The turbo is going to heat the air either way, and the intercooler is going to cool it off. Sxth element posted dyno gains with an open element filter, on a dyno which I imagine would be less airflow through the bay, than driving at 100mph. They showed Gains mainly on the top end, leading me to believe that any increase in IAT's was minimal and that it was more than made up for by the reduced workload on the turbo. (Easier to draw air).

Personally I'll be going open element myself, as the most important piece to controlling IAT on a turbo car is the intercooler.
 
^ Sorry, BOV's aren't designed to reduce IAT's or cool off turbos. They don't affect IAT's at all. Its main purpose is; to take the load off the turbocharger, when the throttle is suddenly closed.

The blow-off valve (BOV) is a pressure-relief valve to prevent, a turbocharger compressor from going into what is known, as surge. That's it. A good aftermarket BOV, (there are cheap ones also) will provide more precise pressure control. They'll aid in faster turbo recovery between shifts, far less surge and flutter as well.

As ambient and engine temps rise, the inflow of air needs to remain cooler. I believe the Forge really needs a heat shield to keep heat soak at bay. Intercooler helps but is not the complete answer.
 
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Open intake ist counterproductive if you don't have heat shielded your intake from your engine. Also a snorkel thing to lead the air into the intake is highly recommended.
Most guys just drive open intake because it's "cool" and for the sound. If you really want performance, you shouldn't do.
 
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I’ve inferred this before... Reduce and control underhood temperatures, then open SRIs (without a heat shield or enclosure) are just fine. WAI also greatly helps.
 
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I am not an expert by any stretch, but I imagine there wont be much difference between a closed box or an open intake. The turbo is going to heat the air either way, and the intercooler is going to cool it off. Sxth element posted dyno gains with an open element filter, on a dyno which I imagine would be less airflow through the bay, than driving at 100mph. They showed Gains mainly on the top end, leading me to believe that any increase in IAT's was minimal and that it was more than made up for by the reduced workload on the turbo. (Easier to draw air).

Personally I'll be going open element myself, as the most important piece to controlling IAT on a turbo car is the intercooler.

I never thought about that actually, but you are somewhat right. I found the formula for turbo outlet temperature and calculated some numbers. The charged air is incredibly hot. So I just guessed what the difference might be between the closed box and open box and based the guess off what my normal IATs are.

Ambient right now around me is about 32C and my IATs are around 40C while cruising. Since I have no idea what the difference between the stock closed box and the open Forge is I just guessed a 4C increase, no idea if that's even close to correct. So calculating the inlet temp at 40C yeilds 144.4C outlet temp. Then recalculating it at 44C outlet temp is 150C. So the difference is about 5.6C outlet temp with a 4C difference in ambient.

So it seems like whatever the difference is between the IAT for the open vs closed box is additive which is nice. It's not a huge difference at those temperatures but it's still a difference and it's almost directly related to IAT. The intercooler is a whole other thing that isn't very easy to calculate unless you have all the data from the manufacturer for the outlet temperature.

I went ahead and ordered the Forge intake yesterday since I just have to assume I won't be getting any data from anyone about it and I'll post my findings when I put it on. My brothers is a welder so I was thinking of having him fabricate me a box for it but the angle of the filter makes it look like it might be kinda hard but I'll probably try anyway we already have a few sketches of what we could do just depends on how it sits.

@R Veloster N Not entirely sure why you brought that up but yeah that's true BOV's do not change IATs.
 
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I never thought about that actually, but you are somewhat right. I found the formula for turbo outlet temperature and calculated some numbers. The charged air is incredibly hot. So I just guessed what the difference might be between the closed box and open box and based the guess off what my normal IATs are.

Ambient right now around me is about 32C and my IATs are around 40C while cruising. Since I have no idea what the difference between the stock closed box and the open Forge is I just guessed a 4C increase, no idea if that's even close to correct. So calculating the inlet temp at 40C yeilds 144.4C outlet temp. Then recalculating it at 44C outlet temp is 150C. So the difference is about 5.6C outlet temp with a 4C difference in ambient.

A lot of people fail to completely comprehend all the variables in play with a turbo car, in regards to IAT. It really makes almost no difference at all how cold the air your drawing in it, when it gets heated, as you saw, to nearly 300*f by the turbo. The turbo itself is hot, and when you compress air it gets a whole lot hotter. Nice find on those numbers though, I'd be interested in checking out the formula you found if you're willing to share.

You will blow peoples mind when you tell them that a bigger intercooler, that lowers their IAT, will also lower their boost pressure, but still make the same if not more power.

After a while you will learn who has a solid base of knowledge on the forums, and which members can be safely ignored. Took me about 2 posts ;)