Flex Fuel Setup for RB in S13

[Eric0]

Hello! 
 

I have decided to run a flex fuel setup on my RB25DET. The engine is fully built with forged internals and GTX3076R turbo. To increase HP, I’ve decided to change my fuel system to flex fuel to enable e85. However, I’m new to this e85 world and would like to be informed correctly for my setup. I’m currently pushing 400HP at 17PSI. 

What fuel pump should I run?

what fuel injectors should I use?

what sensor should I use for e85 and regular octane detection?

 

thank you! 

[Ben C34]

Surely this info is easy to find.. What have you figured out so far?

 

Or you just chasing complete spoon feeding?

[Eric0]

6 hours ago, Ben C34 said:

Surely this info is easy to find.. What have you figured out so far?

 

Or you just chasing complete spoon feeding?

Well, I have found flex fuel fuel pumps and injectors, however, I don’t know much about brands. 
 

For example, I found an AEM flex fuel pump at 340lph. Is that a good fuel pump and enough lph? I currently have a 550 walbro and 740cc deatschwerks my tuner suggested 2 years ago. 
Part Number: 3C1450

Or 

a Bosh 040 in tank fuel pump. 

For injectors I have found:

dynamic 1000cc fuel injectors  or are my current injectors okay to keep?

 

Are these good brands and ratings for 600hp, or does anyone have recommended parts? 

thank you! 

 

 

 

[DaymoR32]

my RB25DET NEO has the following spec:-

400hp on 98 at 18PSI
500hp on E85 at 23PSI

Gtx 3076 .82r garrett with speedflow fittings and braided lines
ATP catch can with speedflow -10 braided lines and fittings
50mm gen V turbosmart external waste gate
Spitfire coils
Custom 3 inch dump into 4 inch HKS exhaust
ARP head studs 
Bosch 1250cc injectors 
Turbosmart fuel reg
Turbosmart fuel filter
Walbro 460l fuel pump with relay
Haltech elite 2500

[robbo_rb180]

Easiest way would be :

Walbro 460/525l

Idx1300 injectors

Quality fuel reg

Continental ethanol (also does temp) 

 

Plenty of head room and should idle nicely 

 

[Eric0]

1 hour ago, DaymoR32 said:

my RB25DET NEO has the following spec:-

400hp on 98 at 18PSI
500hp on E85 at 23PSI

Gtx 3076 .82r garrett with speedflow fittings and braided lines
ATP catch can with speedflow -10 braided lines and fittings
50mm gen V turbosmart external waste gate
Spitfire coils
Custom 3 inch dump into 4 inch HKS exhaust
ARP head studs 
Bosch 1250cc injectors 
Turbosmart fuel reg
Turbosmart fuel filter
Walbro 460l fuel pump with relay
Haltech elite 2500

 

40 minutes ago, robbo_rb180 said:

Easiest way would be :

Walbro 460/525l

Idx1300 injectors

Quality fuel reg

Continental ethanol (also does temp) 

 

Plenty of head room and should idle nicely 

 

Hello! 

Thank you for your input. I think I’ll combine your suggestions and do:

525lph walbro fuel pump 

idx1300cc injectors 

turbosmart fuel regulator /filter 

continental sensor 

 

Additionally, I topped out at 400hp flat due to restricted air flow, so I’m increasing my .62 A/R turbo to a .94. Is this a good idea to get more airflow? 

[robbo_rb180]

Stepping up to a bigger rear housing will help but depends how far you want to move the power band up the rev range a. 82 is a good point for response and power be interesting to see how a bigger housing would go. 

[Eric0]

11 minutes ago, robbo_rb180 said:

Stepping up to a bigger rear housing will help but depends how far you want to move the power band up the rev range a. 82 is a good point for response and power be interesting to see how a bigger housing would go. 

My concern is getting too big of an AR. My .63 is suffocating, so a .94 seems promising. However, would it be too much to still have a esponsive turbo? Could I use a 40-50 shot of NOS to help the turbo spool quicker?  I’m aiming for 600hp. 

My idea is to do flex fuel and increase turbo AR. I have a fully built engine making 400whp, but it’s not where I want it yet. 

[robbo_rb180]

That's fair enough, I know how my sil80 went with Aussie 500hp at the wheels and was very linear with a built Rb25, 6boost manifold and gt3076. 82(2008 spec) and e85. 

If just chasing a power figure adjust baro, temp correction and ramp rate on the Dyno ?  

 

[GTSBoy]

0.94 A/R is quite a large housing for a 3076 sized turbo and will certainly negatively impact on response. 0.82 is already noticeably less nice than 0.63.

Shall we take it that being a 240SX that you're in the US? How then should we interpret the power numbers that you mention? What sort of dyno? Is it a typical high reading US dyno? Or more realistic? The reason I ask is that this post in the RB turbo dyno thread is a good place to draw some idea of what the turbo is capable of. That one had a 0.83 housing and was on E85, making 336rwkW (~450 rwHP), on 19 psi. Depending on how optimistic your dyno is will tell you something about where you sit now and what gain you might get from (a) the bigger housing and (b) going to E85.

Hard to know how much extra power you get from changing to E85 as a blanket rule, but if you apply a 20% discount from the power figure in that post, you get down to ~360rwHP. That's a lower number than you're reporting, on a smaller housing, with lower boost, and no E85.

 

[Eric0]

2 hours ago, robbo_rb180 said:

That's fair enough, I know how my sil80 went with Aussie 500hp at the wheels and was very linear with a built Rb25, 6boost manifold and gt3076. 82(2008 spec) and e85. 

If just chasing a power figure adjust baro, temp correction and ramp rate on the Dyno ?  

 

 

1 hour ago, GTSBoy said:

0.94 A/R is quite a large housing for a 3076 sized turbo and will certainly negatively impact on response. 0.82 is already noticeably less nice than 0.63.

Shall we take it that being a 240SX that you're in the US? How then should we interpret the power numbers that you mention? What sort of dyno? Is it a typical high reading US dyno? Or more realistic? The reason I ask is that this post in the RB turbo dyno thread is a good place to draw some idea of what the turbo is capable of. That one had a 0.83 housing and was on E85, making 336rwkW (~450 rwHP), on 19 psi. Depending on how optimistic your dyno is will tell you something about where you sit now and what gain you might get from (a) the bigger housing and (b) going to E85.

Hard to know how much extra power you get from changing to E85 as a blanket rule, but if you apply a 20% discount from the power figure in that post, you get down to ~360rwHP. That's a lower number than you're reporting, on a smaller housing, with lower boost, and no E85.

 

Hello Robbo_rb180,

I do want a a relatively linear trend throughout my power-band, and it sounds like your build was just perfect! To this day, I’m still thoroughly impressed with your tuning ability! 
 

Hello GTSBoy,

Would a better alternative is to go with another turbo than swapping my housing to a .94? The dyno is a typical high reading dyno. I’ll be sure to check out those threads to become better informed  

 

 

[robbo_rb180]

Thanks Eric. Maybe worth stepping up to a 3576 or 3584 if wanting the power. Check out @Dose Pipe Sutututu build page 72 has good data and setup if wanting good power with response, no need for nitrous on your current set-up might just need rear housing, setup close loop boost control on the link and more timing with the e85. 

 

[GTSBoy]

45 minutes ago, robbo_rb180 said:

Maybe worth stepping up to a 3576 or 3584 if wanting the power.

I was going to say the same thing. No point in crippling a small turbo.

[Eric0]

7 hours ago, robbo_rb180 said:

Thanks Eric. Maybe worth stepping up to a 3576 or 3584 if wanting the power. Check out @Dose Pipe Sutututu build page 72 has good data and setup if wanting good power with response, no need for nitrous on your current set-up might just need rear housing, setup close loop boost control on the link and more timing with the e85. 

 

Hello,

I’ve researched quite a few threads and read through page 72 and everyone prefers the gtx3576r over the 3076r. It produces more power with a smaller AR due to the bigger turbine. I also read that a .82 housing will be about as big a gtx3076r housing should be before it becomes laggy and unproductive. For the time being, I’ll upgrade to a .82 housing and get a front mount intercooler (mine is pretty small, 24x12x4.5). 
 

I was reading a forum and a guy said: 

“Im running the GTX30R with .82 Tial housing. Spool is very quick, awesome turbo for the street.” Then a dyno graph was posted. 
 

Do exhaust housing brands affect the flow of the turbo? Tial is famous for their v-band flanges, are they better to regular T3/T4? 
 

I’m currently planning for:

.82 tial housing (thermo coating the housing)

525lph walbro fuel pump 

idx1300cc injectors 

turbosmart fuel regulator /filter 

continental sensor

76mm FMIC (still need to do more research on this)

 

 

[Dose Pipe Sutututu]

Hello I am no dead, but my car is lol...

Whatever you do, go get a twin scroll housing, and a proper twin scroll manifold.

The GTX3576 Gen 2 with the 1.01 divided rear comes on full noise by about 4500rpm (that's 2 bar of boost) and makes well over 1 bar of boost by 4000rpm (confirmed once I put on the new FMIC as the old one was leaking).

That graph you've posted looks laggy.

 

[Eric0]

43 minutes ago, Dose Pipe Sutututu said:

Hello I am no dead, but my car is lol...

Whatever you do, go get a twin scroll housing, and a proper twin scroll manifold.

The GTX3576 Gen 2 with the 1.01 divided rear comes on full noise by about 4500rpm (that's 2 bar of boost) and makes well over 1 bar of boost by 4000rpm (confirmed once I put on the new FMIC as the old one was leaking).

That graph you've posted looks laggy.

 

I have heard about twin scroll setups but I have a question, does the exhaust manifold require two wastegates? 
 

theoretically, if I go with a twin scroll setup, I’m currently running a 44mm wastegate. Would I neede a second 44mm wastegate to go to the other side? 

[GTSBoy]

Yes, and no. To not ruin the split pulse design, you have to make sure that both halves of the manifold have equal access to wastegating and will not interfere with each other. The best way to be sure of that is to have 2x wastegates with no communication between them upstream of their seats. If you have 1x 44, then you wouldn't need 2x 44s. You could downsize.

It is possible to design a split pulse manifold with a common wastegate outlet. Obviously there needs to be complete isolation of the two branches feeding the 'gate, and there should be a divider all the way up to the flat of the 'gate valve. This will provide sufficient isolation between the halves of the manifold....up until the 'gate cracks open. Then, sadly, there will be communication between the two halves of the manifold and pressure pulses will "leak". This is less of a problem than it sounds though, because the whole split pulse thing is more important when trying to spool the turbo than when making set boost. Split pulse housing/manifold doesn't really make any more power than a single inlet turbo does. it just makes it more responsive.

[Dose Pipe Sutututu]

48 minutes ago, Eric0 said:

I have heard about twin scroll setups but I have a question, does the exhaust manifold require two wastegates? 
 

theoretically, if I go with a twin scroll setup, I’m currently running a 44mm wastegate. Would I neede a second 44mm wastegate to go to the other side? 

Sinco make these pretty sexual manifolds (this is mine below).

As you can see each pulse is separate to the seat of the gate, other so called split pulse manifolds end up merging the pulses together which in theory wouldn't perform as well as this.

I run a 50mm gate and it controls boost very well, I can go from 0.5 bar to 2 bar using a 4 port solenoid.

[Eric0]

4 hours ago, Dose Pipe Sutututu said:

Sinco make these pretty sexual manifolds (this is mine below).

As you can see each pulse is separate to the seat of the gate, other so called split pulse manifolds end up merging the pulses together which in theory wouldn't perform as well as this.

I run a 50mm gate and it controls boost very well, I can go from 0.5 bar to 2 bar using a 4 port solenoid.

Oh man!! That is super funny to describe an exhaust manifold in that manner!! Haha, what’s a good laugh. 
 

Those are pricy! I’m seeing one for $1042. Plus $400 for the twin scroll housing, that puts me at 500- 800 more and I can just get a GTX3576r turbo and keep my current setup. Is a twin scroll setup worth it? 
 

GTX3076R .82AR Twin Scroll with Since twin scroll manifold 

~1600

OR

GTX3576r .62AR and keep my single scroll exhaust manifold 

~1900

 

I will also be purchasing:

525lph walbro fuel pump 

idx1300cc injectors 

turbosmart fuel regulator /filter 

continental sensor

76mm FMIC 

 

goal 500+ but hopefully 600hp, I’m currently at 400hp pump gas

 

[Dose Pipe Sutututu]

3 hours ago, Eric0 said:

Is a twin scroll setup worth it? 

If you're after low down, good spool, good mid range power then yes. Also depends how the car is used.

If it's for drags, drifting or roll racing then perhaps it's not worth the investment but if it's used for circuit racing or driving through windy roads then 100% worth the extra money.

0.62 is too small.