rb26dett with single turbo and twin maf?

[GAWDZRA]

turbo xs lol i used to use one of their blue anodized manual boost controllers , and even that replaced the original manual one i made out of some brass fishtank fittings lol. And my knockbox looked like a radioshack DIY kit , didn't look as flashy as the new ones lol

Holy crap.. those homemade sping ball mbc's made from brace fittings from a hardware store! haha.. i remmember back in 2004 when i had my 94 wrx setup with nissan parts on it and pfc. ahhhhh memories..

Anyways, seems like ill give this a shot. if anyone else have actual experience with this set up feel free to post up your setup and any additional input/info would be nice.

[Dragon Humper]

Your power goals are not "pie in the sky" so there is nothing that Nistune can't fix, you can even go bigger injectors if you wish.

I personally think that twins on a GTR was nothing more than a maketing ploy. Why do you think that they put ceramic turbines on the stockers? Because the lag was to bad with steel. 6 pulses acting on a turbine in 2 revelutions can have more of an effect than 3. A divided tang and flange on the turbine housing works even better.

Another bonus is that a bigger single won't heat up the air as much as undersized stockers, that takes the strain off the intercooler and allows you to run more ignition timing. This can make you MUCH more torque at a lower psi giving you the thrust that you want with more reliability than the stock twin setup (heat soak, more chance for leaks, shuffle, weight, etc.....).

BTW your tire analogy was right on, PSI is definetly NOT PSI. One thing that is not being taken into acount is that in order to run that larger turbo, everything must also be larger, including the turbine housing. This opens up alot of restrictions (that is what is producing the pressure, restrictions) and allows an engine to flow much more air at a given pressure (which directly translates into a power increase). I suggest you find your deal on a tubular manifold first (harder to find than a turbo), then pick your turbo. If you find a screaming deal on an open flange, go that direction (least desireable), if you can find a divided flange (T4, most desireable) manifold get the smallest turbo to fit it and you should be kickin'. I can make as much power at .5bar than stockers can make at 1bar. At 1 bar I can make about 150hp more with a cooler intake charge.




Jon.

[M13]

Your power goals are not "pie in the sky" so there is nothing that Nistune can't fix, you can even go bigger injectors if you wish.

I personally think that twins on a GTR was nothing more than a maketing ploy. Why do you think that they put ceramic turbines on the stockers? Because the lag was to bad with steel. 6 pulses acting on a turbine in 2 revelutions can have more of an effect than 3. A divided tang and flange on the turbine housing works even better.

Another bonus is that a bigger single won't heat up the air as much as undersized stockers, that takes the strain off the intercooler and allows you to run more ignition timing. This can make you MUCH more torque at a lower psi giving you the thrust that you want with more reliability than the stock twin setup (heat soak, more chance for leaks, shuffle, weight, etc.....).

BTW your tire analogy was right on, PSI is definetly NOT PSI. One thing that is not being taken into acount is that in order to run that larger turbo, everything must also be larger, including the turbine housing. This opens up alot of restrictions (that is what is producing the pressure, restrictions) and allows an engine to flow much more air at a given pressure (which directly translates into a power increase). I suggest you find your deal on a tubular manifold first (harder to find than a turbo), then pick your turbo. If you find a screaming deal on an open flange, go that direction (least desireable), if you can find a divided flange (T4, most desireable) manifold get the smallest turbo to fit it and you should be kickin'. I can make as much power at .5bar than stockers can make at 1bar. At 1 bar I can make about 150hp more with a cooler intake charge.




Jon.

amazing, thanks Jon!

[Skym]

Stock GTR ECU (has a knock board inside) is good at detecting knock. It's as accurate as a aftermarket electronic knock detection device, as both detect knock at same time.

The difference I have noticed between the 2x setups (twin, single turbo) is the twin setup is smoother (best way I could describe what you feel) in transistion to boost. If you think about it, on racetrack you don't want car suddenly snapping sideways when exiting a corner with a single turbo, so a twin setup with smoother transistion (not a quick, violent transistion) to boost makes sense. Mix with 4wd adding torque to front wheels if rear starts to step out and have a good combination for a quick trackcar. Also I remember reading about this smoother transistion with twin turbo's (why they fitted a twin turbo setup) in a article I read ages ago on I think was the Ferrari F40 with twin turbo setup. Wish I could find it again.

The twin turbo Supra reminds me of this videoclip of a Ferrari F40 vs Supra -

http://www.youtube.com/watch?v=jOOlOLeCOww

With twin N1 turbo's (metal exhaust wheel) they reach around 1bar at around 4000rpm (with cams) and really accelerates. Factory is at around 3800rpm, so not that much of a difference.

For MAF, can run a 700hp rated Ford Racing Lightning MAF (for a supercharged Ford Lightning) with stock ECU + Nistune (it's in the drop down menu when changing MAF). Some aftermarket Ford Lightning MAF's are rated to 700hp+, but finding the translation table for MAF voltage (or this data that sometimes is posted on forums) on ECU could be a bit hard.

This RB20DET with Nistune inside stock ECU runs a Ford Lightning MAF + intake piping adaptor (blow through setup) -

http://www.youtube.com/watch?v=k2cREcerhyk

From what I understand, blow through MAF should be mounted inbetween BOV, intake plenum.

[GAWDZRA]

Your power goals are not "pie in the sky" so there is nothing that Nistune can't fix, you can even go bigger injectors if you wish.

I personally think that twins on a GTR was nothing more than a maketing ploy. Why do you think that they put ceramic turbines on the stockers? Because the lag was to bad with steel. 6 pulses acting on a turbine in 2 revelutions can have more of an effect than 3. A divided tang and flange on the turbine housing works even better.

Another bonus is that a bigger single won't heat up the air as much as undersized stockers, that takes the strain off the intercooler and allows you to run more ignition timing. This can make you MUCH more torque at a lower psi giving you the thrust that you want with more reliability than the stock twin setup (heat soak, more chance for leaks, shuffle, weight, etc.....).

BTW your tire analogy was right on, PSI is definetly NOT PSI. One thing that is not being taken into acount is that in order to run that larger turbo, everything must also be larger, including the turbine housing. This opens up alot of restrictions (that is what is producing the pressure, restrictions) and allows an engine to flow much more air at a given pressure (which directly translates into a power increase). I suggest you find your deal on a tubular manifold first (harder to find than a turbo), then pick your turbo. If you find a screaming deal on an open flange, go that direction (least desireable), if you can find a divided flange (T4, most desireable) manifold get the smallest turbo to fit it and you should be kickin'. I can make as much power at .5bar than stockers can make at 1bar. At 1 bar I can make about 150hp more with a cooler intake charge.




Jon.

YES! this is exactly what i was trying to accomplish!! ive talked to a couple people running a midsized single (gt3076r) running 12psi and runs great and no issues at all.

Also what is nistune? is this kinda like a "open ecu tuning"? a cable/software tuning program for the factory GTR ecu? hmm.. interesting.

[GAWDZRA]

Stock GTR ECU (has a knock board inside) is good at detecting knock. It's as accurate as a aftermarket electronic knock detection device, as both detect knock at same time.

The difference I have noticed between the 2x setups (twin, single turbo) is the twin setup is smoother (best way I could describe what you feel) in transistion to boost. If you think about it, on racetrack you don't want car suddenly snapping sideways when exiting a corner with a single turbo, so a twin setup with smoother transistion (not a quick, violent transistion) to boost makes sense. Mix with 4wd adding torque to front wheels if rear starts to step out and have a good combination for a quick trackcar. Also I remember reading about this smoother transistion with twin turbo's (why they fitted a twin turbo setup) in a article I read ages ago on I think was the Ferrari F40 with twin turbo setup. Wish I could find it again.

The twin turbo Supra reminds me of this videoclip of a Ferrari F40 vs Supra -

http://www.youtube.com/watch?v=jOOlOLeCOww

With twin N1 turbo's (metal exhaust wheel) they reach around 1bar at around 4000rpm (with cams) and really accelerates. Factory is at around 3800rpm, so not that much of a difference.

For MAF, can run a 700hp rated Ford Racing Lightning MAF (for a supercharged Ford Lightning) with stock ECU + Nistune (it's in the drop down menu when changing MAF). Some aftermarket Ford Lightning MAF's are rated to 700hp+, but finding the translation table for MAF voltage (or this data that sometimes is posted on forums) on ECU could be a bit hard.

This RB20DET with Nistune inside stock ECU runs a Ford Lightning MAF + intake piping adaptor (blow through setup) -

http://www.youtube.com/watch?v=k2cREcerhyk

From what I understand, blow through MAF should be mounted inbetween BOV, intake plenum.

i understand where you are coming from. but theres tons of tools/ways to make a single setup to be as smooth a twin set up. You can fine tune some electronic boostcontroller for a gradual boost so when it hits, its not as voilent. As far as twins being good at the track, well.. lets just say that theres a crap load of large single turbo proven track monters all over the world. Its all footwork when it comes to the track. you can easily over power a turn in any car single /twin/ even underpowered NA cars. its all about regulation of the gas pedal. So that arguement that twins are better at the race track is somewhat invalid given the amount of cars performing at a highlevel not having them.

[Oakville]

Do the twin maf with the big single. Y pipe with two z32 mafs should do it.

[Skym]

i understand where you are coming from. but theres tons of tools/ways to make a single setup to be as smooth a twin set up. You can fine tune some electronic boostcontroller for a gradual boost so when it hits, its not as voilent. As far as twins being good at the track, well.. lets just say that theres a crap load of large single turbo proven track monters all over the world. Its all footwork when it comes to the track. you can easily over power a turn in any car single /twin/ even underpowered NA cars. its all about regulation of the gas pedal. So that arguement that twins are better at the race track is somewhat invalid given the amount of cars performing at a highlevel not having them.

I agree that boost controller plays a role, so does tune.

I guess I should show with videoclips, as it's hard to understand without experiencing both.

This R34GTR trackcar is a good example of boost hitting hard, quick with a big single -

http://www.youtube.com/watch?v=ikSsxO0Q9aM

Then compare to twin turbo setup on R35GTR with similar awhp -

http://www.youtube.com/watch?v=nRzHEPeK33U

Both cars have slicks, race suspension, etc, but with smoother transistion to boost with twin turbo. Same difference comparing my car to a mates GTR racecar and his cars engine has more hp but similar size twin turbo's to single turbo on my car.

[GAWDZRA]

I agree that boost controller plays a role, so does tune.

I guess I should show with videoclips, as it's hard to understand without experiencing both.

This R34GTR trackcar is a good example of boost hitting hard, quick with a big single -

http://www.youtube.com/watch?v=ikSsxO0Q9aM

Then compare to twin turbo setup on R35GTR with similar awhp -

http://www.youtube.com/watch?v=nRzHEPeK33U

Both cars have slicks, race suspension, etc, but with smoother transistion to boost with twin turbo. Same difference comparing my car to a mates GTR racecar and his cars engine has more hp but similar size twin turbo's to single turbo on my car.

But see.. you cant use youtube videos to do a comparison. thats like trying to prove a thesis sourcing everything from wikipedia.. not to mention 2 totally different cars in 2 totally different environment. Have you personally done any track driving before? its all about smooth footwork and smooth lines. You dont just floor it and hope that car does fine around the track. You posted a r35GTR on a road corse and compared it to some dude mashing the gas pedal on some street doing a pull?!?!?!

same horsepower has nothing to do with anything. first of all the r35 has bigger displacement than an r34 making it smoother to begin with but thats besides the point. i dont get your reasoning behind the choice of vehicles to comepare. my mind is blasted.

Thank you for the input though.

[Dragon Humper]

I have to agree with you awd_pwnz, that is not a very good comparison, unless you want to really complicate things, you MUST run twins on a V engine, otherwise would (is, I've done it) be a PITA. The R35's boost is coming in hard, he just doesn't have it wound up very tight (most likely only 1.2 bar). And that particular R34 has a fairly large turbo and 4.11 gears (stock is 3.54) so it kind of sounds like a madman, I think I could take it though.......lol.

You can make your boost come in as gentle or hard as you want with a quality controller and a nice big wastegate. And like Skym said, the tune also plays a big part. You can back off the ignition timing a whole bunch while you are in transition and then bring it back in slowly to give you a more gentle boost curve. I, however, like my sledgehammer and use my right foot to regulate power (I am running a D-Jetro though). I don't plan on tracking a whole lot, more street and drag.

Nistune (you'll have to do a search) lets you tune the factory ECU with a socketed factory board and a cable/tuning suite on your laptop. Like Oakville said, a couple of Z32 MAFs and Nistune and you could run up to 1 bar and 600cc injectors with little fuss and make about 500 reliable HP. You will also be dumping about 40lbs off the front end of the car by going single.




Jon.

[Skym]

I was trying to show the sudden acceleration difference. One of those things that has to be experienced.

[GAWDZRA]

point is....

Both can have the same exact acceleration feel.

Both can be as violent and sudden as each other.

Both can be as smooth and have a nice transition to full boost.

[Dragon Humper]

Really though, unless you are going for more than 1200hp, you don't need twins. A well setup single will be exactly as responsive as a set of twins at a given HP level.

I hear some guys complain about lag with -5s, it all depends on your perseption of lag.



Jon.

[Super_Dude]

Why would you need twins for more than 1200hp? Heat treatments runs a single (1600whp)

I wouldnt say a single turbo saves any weight over twins though. Maybe a little but not 40lbs.

I love singles

Twins are for cookie cutter builds.

[Skym]

Then why have twin turbo's, when they could have used a single turbo?

I assume Skylines run a parrallel twin turbo setup (as mentioned in link below) and is said in theory to reduce lag -

http://en.wikipedia.org/wiki/Twin-turbo

Engineers have a reason behind everything they do.