DBV2 Twin Scroll Bottom Mount

Bigdaddyaaron

Corporal
Nov 5, 2016
145
110
0
USA
Straight pump gas. Just a Precision LPFP and see what I get. That’s going to be my car anyways. Road racing car.
My guess is you will see 20ish psi @ 3200-3500 (depending on the turbo) and a *safe* max output of +/-480whp (assuming 93oct). More on race gas

How do you plan on doing that? You planning on running straight pump gas on this? Shotgunning the HPFP?
You wont need a shotgun for 93 oct. More vol/unit than ethanol mixes.
 
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John@DBV2

Sergeant
Jan 23, 2017
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My guess is you will see 20ish psi @ 3200-3500 (depending on the turbo) and a *safe* max output of +/-480whp (assuming 93oct). More on race gas

You wont need a shotgun for 93 oct. More vol/unit than ethanol mixes.
I think we’re going to see quite a bit more than 480. My guess is 550+ but we will see soon ;)
 

gixercho

Specialist
Mar 3, 2018
54
42
0
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E92 335i Custom ST
562whp from me on pump 93, bottom mount Vband and the HPFP was maxed, i think twinscroll will help a little with the timing too, so with more fuel with shotgun or other fueling method is possible
 
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John@DBV2

Sergeant
Jan 23, 2017
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562whp from me on pump 93, bottom mount Vband and the HPFP was maxed, i think twinscroll will help a little with the timing too, so with more fuel with shotgun or other fueling method is possible

Thanks for sharing that! We have 94 here local and readily available and it has a 10 percent E content. I think 550+ will be no problem at all. What turbo were you running on that?
 

Bigdaddyaaron

Corporal
Nov 5, 2016
145
110
0
USA
I think we’re going to see quite a bit more than 480. My guess is 550+ but we will see soon ;)
The problem with going higher than that is octane safety. On this relatively higher comp 10.2:1, octane is much more of a limiting factor than anything else. Anything above 500 is asking for trouble due to variances in fuel quality and air temp. That's why I said *"safe* max output".
562whp from me on pump 93, bottom mount Vband and the HPFP was maxed, i think twinscroll will help a little with the timing too, so with more fuel with shotgun or other fueling method is possible
You wilin lol. How would twinscroll help with timing?
 
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John@DBV2

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Jan 23, 2017
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The problem with going higher than that is octane safety. On this relatively higher comp 10.2:1, octane is much more of a limiting factor than anything else. Anything above 500 is asking for trouble due to variances in fuel quality and air temp. That's why I said *"safe* max output".

You wilin lol. How would twinscroll help with timing?

Well we can share our data logs once we’re finished. I won’t be pushing the engine into unsafe territory. I can assure you there is lots of room above 500 even including variance of fuel quality etc. It’s incredible what these cars can do with just pump gas.

Twin scroll is just better, it moves and utilizes exhaust gases more efficiently and makes more power all through the range.
 

gixercho

Specialist
Mar 3, 2018
54
42
0
Ride
E92 335i Custom ST
3582HTZ with Tial .82 Vband housing. May be better timing because gases dont mix themselves so much and help for cooler head, i saw some reviews from other platforms where knock starts to appear with lower on open scroll turbos then twin. This doesnt mean that open scroll is bad.
 

JDKruger4

Private
Aug 10, 2017
26
23
0
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335i LCI
Watching this kit. Not looking to make huge power, but have a reliable 500 whp on my daily with good spool. Ideally, I'll run stock fueling (with Stg2 LPFP) and tune to max out the HPFP on E85 (have the Flex Fuel kit waiting to go on). I have cheap E85 readily available and I'd be happy (for now) with whatever I could get out of that knowing the turbo has headroom and I'm stressing the motor much less than making that power on stockers.
 

Jpotter

Private
Oct 8, 2017
42
26
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2007 335i
Intrested in this kit. If its around 4k im intrested. 5k and i might go doc racing unless people are in love with this. Im only looking to make 500. Only have 91 and 1 pump in that has e85.
 

ShocknAwe

Captain
Jan 24, 2018
1,472
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Charleston, SC
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N54/3 1er ///Mutt
just based on other kit and small stock frame hybrid performance, there's no reason to think 500 wouldn't be possible with a mid sized turbo and GOOD pump gas. Hell, you can hit 500 on stock twins with ethanol. But, impossible to say until the testing starts. Logs and proper dynos will tell all.
 

gixercho

Specialist
Mar 3, 2018
54
42
0
Ride
E92 335i Custom ST
No matter what bulls..ts most people talking about, this turbo kit is not capable for 500... its capable even for more then 800whp with the right size turbo and fuel. Just because the guy dont have acces to e85 or meth and dont have fueling supporting mods for this, doesnt mean that if somebody have them will not make 700 or 800 or even more with the T3 flange with that kit. Educate yourselves before make statements that may be T3 will make only 500 or may be little more, It will make 500 even with stupid small gtx2871 gen2. If you read some will see that T3 twin scroll have almost triple port area then Pure stage 2 turbo for N55 engine and can produce around 550 no problem, so T3 flange is no restriction for much more power. I can continue talk about this, but have no time right now.
 
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ShocknAwe

Captain
Jan 24, 2018
1,472
1
729
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Charleston, SC
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N54/3 1er ///Mutt
No matter what bulls..ts most people talking about, this turbo kit is not capable for 500... its capable even for more then 800whp with the right size turbo and fuel. Just because the guy dont have acces to e85 or meth and dont have fueling supporting mods for this, doesnt mean that if somebody have them will not make 700 or 800 or even more with the T3 flange with that kit. Educate yourselves before make statements that may be T3 will make only 500 or may be little more, It will make 500 even with stupid small gtx2871 gen2. If you read some will see that T3 twin scroll have almost triple port area then Pure stage 2 turbo for N55 engine and can produce around 550 no problem, so T3 flange is no restriction for much more power. I can continue talk about this, but have no time right now.

I thought that was already well established? Evidence /cough/ motiv /cough/
 

Clean WHP

Corporal
Apr 24, 2017
173
136
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2010 135i Msport 6MT
the limiting factor for single turbo cars on pump gas is not the pump gas persay, Its the HPFP. Of course, we all know know you will need a LPFP upgrade of some sort, but the HPFP just runs out of flow

From my understanding, every car/n54 HPFP is different where they run out of flow depending on the age/health of the hpfp. The Direct Injection itself can flovide plenty flow, its just the hpfp. This is why the shotgun was invented, so people can have more fuel for more HP then what the stock HPFP can flow.

From my research I've seen cars run out of fuel from the HPFP anywhere from 520WHP to 600WHP on singles. Ever car seems to be different in this aspect. Also, Good old 93 octane has plenty enough octane to make 550-600whp, especially with the turbo sized appropriately.

When I was FBO on a custom 93 octane only tune, I was targeting about 19-19.5 PSI safety in the winter months. Depending on the rest of the set up and how efficient the whole build is (good flowing manifold, good FMIC, catless exhaust, IC piping, etc) I would think 93 octane can safety provide enough octane to run 19-21PSI provided the HPFP can keep up.

Here is an old thread of a 6466 (Gen 1 I believe) Making 600WHP on just 91 octane back in 2013 on 21PSI, granted it was a fairly aggressive tune, but still. Here in 2018, with all the advancements to the platform and bolt ons getting getter, I think a properly set up car on 93 octane on a 6466 could make 600whp at even less than 21PSI making it do-able for sure, if your HPFP is in good health. if not, then all bets are off I guess
http://www.e90post.com/forums/showthread.php?t=829687
showthread.php
 
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JDKruger4

Private
Aug 10, 2017
26
23
0
Ride
335i LCI
From my research I've seen cars run out of fuel from the HPFP anywhere from 520WHP to 600WHP on singles. Ever car seems to be different in this aspect. Also, Good old 93 octane has plenty enough octane to make 550-600whp, especially with the turbo sized appropriately.
showthread.php

Any idea where the HPFP runs out of flow on 100% E85 with a smaller ST? I'd imagine its lower than on 91 oct. 400WHP, 500WHP? My dream is the 450-500WHP reliable daily running a smaller ST on E85 with no fueling upgrades beyond LPFP, lines, and Flex Fuel kit. Maybe I should just stick with the twins but I love the simplicity of the ST and greater reliability not to mention less stress on the motor due to reduced back pressure.
 
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dyezak

Major
May 4, 2017
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Plano TX
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335is
Any idea where the HPFP runs out of flow on 100% E85 with a smaller ST? I'd imagine its lower than on 91 oct. 400WHP, 500WHP? My dream is the 450-500WHP reliable daily running a smaller ST on E85 with no fueling upgrades beyond LPFP, lines, and Flex Fuel kit. Maybe I should just stick with the twins but I love the simplicity of the ST and greater reliability not to mention less stress on the motor due to reduced back pressure.

~450hp

I'm at 420hp and my rail pressures are showing that I'm out of HPFP flow. But some people have more flow than that but a little bit.
 

John@DBV2

Sergeant
Jan 23, 2017
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Yes, but most people think it have to be proven with every kit, like the physic laws are not equal for every one of them.
Haha loved the physics comment, sitting here eating dinner at a restaurant laughing by myself like some kind of psycho.
 
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John@DBV2

Sergeant
Jan 23, 2017
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@Clean WHP

That 6466 is an excellent example. Not even necessary to run a turbo that big either, 21 psi that thing is barely breathing! All it’s doing is slowing down spool with a large turbo like that. Thanks for the information btw, great to have that here for people who just simply don’t know.
 
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Payam@BMS

Sergeant
Oct 27, 2016
412
265
25
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With this much skill I wish you went T4 and killed it. Looks fantastic though, keep it up!

Holy jumping into conclusions batman. I said one thing about T4 and all these guys going crazy about power limits. Nobody even brought that up. Youre limited by turbo options for a twin scroll T3 thats the only downside. This kit will do exactly what all other kits do.