[Jerain]

Maybe a stupid question, but if you have a BOV type chargepipe and instead of capping off the 2 stock DV openings on the inlets, you mount 2 small 7/8" inletsize airfilters would that give better/extra airflow to the turbos? Just like DCI's it's exposed a bit more to engine bay heat but you still have a mix with the cold air with the stock airbox (with scoops).

Maybe a good alternative for Mr.5 intake and people like me that want to keep the stock airbox look.

[Jeff@TopGearSolutions]

Originally Posted by Jerain

Maybe a stupid question, but if you have a BOV type chargepipe and instead of capping off the 2 stock DV openings on the inlets, you mount 2 small 7/8" inletsize airfilters would that give better/extra airflow to the turbos? Just like DCI's it's exposed a bit more to engine bay heat but you still have a mix with the cold air with the stock airbox (with scoops).

Maybe a good alternative for Mr.5 intake and people like me that want to keep the stock airbox look.

Likely negligible plus it's hot air over there. If you already have DCI there is probably little to gain as the restriction is now in the inlets.

[Jerain]

Originally Posted by Jeff@TopGearSolutions

Likely negligible plus it's hot air over there. If you already have DCI there is probably little to gain as the restriction is now in the inlets.

Thanks but that doesn't answer my specific question regarding my setup.

This "mod" will likely make zero difference.

[CoffeeBean]

Not big enough to make any difference. Do what I did on my old N54 and couple the Z4 lid with a Mr.5 intake.

[Cabdriver]

So like breather valves? That would make a difference if the main filters were restrictive enough that the two smaller ones added flow which is tied to the capacity of the inlets.
Breather valves are cheap enough try it out!

[Bimmer_Engineer]

Wait...so you want to take the holes in your pressurized intake and rather than leaving them plugged you want to leave them open but put an air filter on them?

Hmmm...

Originally Posted by FCobra94

This "mod" will likely make zero difference.

I would contend that it will actually make a difference...a big difference!

[E92 420]

Originally Posted by Bimmer_Engineer

Wait...so you want to take the holes in your pressurized intake and rather than leaving them plugged you want to leave them open but put an air filter on them?

Hmmm...



I would contend that it will actually make a difference...a big difference!

Nothings pressurised it’s under vacuum and no it won’t make a big difference at all.

Why do you think it will?

[Bimmer_Engineer]

Originally Posted by E92 420

Nothings pressurised it’s under vacuum and no it won’t make a big difference at all.

Why do you think it will?

What are you talking about? The DVs attach to the charge pipe...the charge pipe is pressurized...if you put air filters on the bungs where the DVs are supposed to go then boost will leak out...

[Jerain]

Originally Posted by Bimmer_Engineer

What are you talking about? The DVs attach to the charge pipe...the charge pipe is pressurized...if you put air filters on the bungs where the DVs are supposed to go then boost will leak out...

On the inlets as I said in first post, not on the chargepipe.

[Bimmer_Engineer]

Originally Posted by Jerain

On the inlets as I said in first post, not on the chargepipe.

Ahh...nvm then...

[Jerain]

Originally Posted by Bimmer_Engineer

Ahh...nvm then...

Haha no problem, can happen sometimes. Anyway I have bought the 2 airfilters and going to test and log it... Cost me 10euros and can still use them as breather filters.

[Cabdriver]

Originally Posted by Jerain

Haha no problem, can happen sometimes. Anyway I have bought the 2 airfilters and going to test and log it... Cost me 10euros and can still use them as breather filters.

[Jerain]

Well upgraded my chargepipe today and decided to do as the title says, 2 small airfilters on the stock dv to inlets connection. Will upload some pics later. Works perfect, already feels like better top end power, much less turbo howl/whine when drifting in high rpm. I have cut off the 2 stock tubes to the chargepipe connections so now 2x vent to atmosphere, sounds great!

Need some more logging with this V8 E30 MHD, really hard when roads are soaking wet and wheelspin u tot 4-5th gear lol.

[Jerain]

[Jerain]

My car

[nissubaru]

My head hurts trying to figure out how that is not causing a massive boost leak?

[Jerain]

Originally Posted by nissubaru

My head hurts trying to figure out how that is not causing a massive boost leak?

Why should it have a boost leak, nothing has changed on the boost pressurised side to the throttlebody exept for stock DV modded to BOV vent to atmosphere...

Only now I have a stock airbox with Z4 lid and K&N drop in combined with a small Dual Cone Intake.

Most import part, it looks stock for the untrained eye, local police and technical inspection is difficult over here in europe.

[srey]

Originally Posted by nissubaru

My head hurts trying to figure out how that is not causing a massive boost leak?

Because it's on the inlet side. Air isn't pressurized on that side of the turbo. Rather, it's being sucked in. Think pull vs. push.

[BMWdmk]

+1 Where he is putting the small filter is the half way point of the turbo inlet. Most would just attach a filter at the ends (Dual Cone Intake) essentially ditching the airbox altogether. He's basically adding dual cone intake (much smaller version) to his airbox/ factory intake.

The diverter valves are still attached to charge pipe and seem to function as VTA BOV but are not connected by the tube that dumps the excess air into the intake where the little filters are now sitting.

[Jerain]

So first day it was a bit dry and cold here, so first datalogging with this setup (details in signature). Car felt very fast, more grunt up top. Drove the V8 E30 map and my WGDC dropped a massive average 20% in high rpm!! Car breathes much better now, makes lovely turbo spooling and BOV noises! I can recommend these mods to anyone!

My best Virtual dyno showed 461whp on smoothing 5 with just 10 liters of pure 100% ethanol mixed with 30 liters 95RON. Even if those numbers seem a bit optimistic, I'm very happy. I will be running the E50 or E60 map in spring and summer so will be even better.

https://datazap.me/u/jerain/mhd-v8-e...data=3-4-20-28

[Sgop335]

Originally Posted by Jerain

So first day it was a bit dry and cold here, so first datalogging with this setup (details in signature). Car felt very fast, more grunt up top. Drove the V8 E30 map and my WGDC dropped a massive average 20% in high rpm!! Car breathes much better now, makes lovely turbo spooling and BOV noises! I can recommend these mods to anyone!

My best Virtual dyno showed 461whp on smoothing 5 with just 10 liters of pure 100% ethanol mixed with 30 liters 95RON. Even if those numbers seem a bit optimistic, I'm very happy. I will be running the E50 or E60 map in spring and summer so will be even better.

https://datazap.me/u/jerain/mhd-v8-e...data=3-4-20-28

Good hp, but lots of throttle closure. Wonder if the "before" log was similar or is all the "extra" air doing this