supercharged twin turbo 2jz - lets brainstorm

[RobV]

im not sure of power, was tuned with data logging, As had no dyno access at the timewas running approx 80% duty cycle on 880cc injectors at 33psi with a 13:1 a/f ratio, went through couple clutches, new setup will be alot easier and more efficient ,have right parts wolf v500 ecu, intercooling between both stages ,hub dyno access , lol getting high tech

[JustenGT8]

im not sure of power, was tuned with data logging, As had no dyno access at the timewas running approx 80% duty cycle on 880cc injectors at 33psi with a 13:1 a/f ratio, went through couple clutches, new setup will be alot easier and more efficient ,have right parts wolf v500 ecu, intercooling between both stages ,hub dyno access , lol getting high tech

A really rough calc gives me approx 720hp but regardless it would have been pretty healthy and hell responsive

[RobV]

it had imazing ressponce around 24psi 3000rpm, am really looking forward to seeing what its like with a twin screw and well suited turbo,

[seamonsta]

Besides the obvious "Cos I can" and "I'm a Kiwi Bro" any real reasons to build the man mountain motor?
Not that I am dissing you, big respect for actually doing it and making it work but I do wonder why!

[JustenGT8]

it had imazing ressponce around 24psi 3000rpm, am really looking forward to seeing what its like with a twin screw and well suited turbo,

Hmmi thought it would have been better than that? Mine had 250rwkw at 3000rpm!! 6psi boost off idle (1000rpm) so stupid grunt straight off the bat. Even with my ridiculous 2.92:1 rear end i could start in 2nd gear and break traction at will

Peak boost of 25psi and hellish inlet temps were the scary bits..... resolveable but car went in a different direction so never had to bother.

[RobV]

prolly board, allways muckn rnd in da shed wit suthing, and couldnt really find much info about it , had been developing the s engine trying different turbos started with a turbonetics t58 ptrim.58a/r, then went to a t66 compressor and .7 twin scroll, but found it a bit lacking in ressponce ,but cranking at high boost, just happened accross a sc14 with a extended snout , had a week holiday from work, and couple slabs kiwi ale. pretty much put it 2geather in 2days drivn rnd on friday

[RobV]

yea i found that aswell ,I think the toyota blowers are very poor in efficiency originally i had the idea to run the system in paralell, with a reflux valve, running the blower at a 3 to 1 overdrive thinking that it would only be running to around 4000rpm max,and wanting to get every last Rpm outa the blower, this never quite worked as planned tho, as the turbo would spool up compound with the blower wich was allready way overdriven and out of efficiecy and the turbo way chokeing up and doing all kinds of noises, back pressure was way up due to compressor only running around 3psi and big airflow way out in the chock flow, then the blower cluch would disengauge around 4000rpmand the car would take off just running on t66, no gd but could see the potential, geared the blower right down low boost 8-10psi, and added extra turbo. Turbos were running from 6-15psi into the blower. and intercooler, , this really performed much more nicely very smooth boost around 4000rpm ,postive inlet pressure to back pressure ratio, through the entire rev range, and seemed to just keep gobbling fuel the more boost and RPM you fed it

[white_sandshoe]

Besides the obvious "Cos I can" and "I'm a Kiwi Bro" any real reasons to build the man mountain motor?
Not that I am dissing you, big respect for actually doing it and making it work but I do wonder why!

Is "I wanna go fast" a good reason? Do we really need a reason though? I don't. Bring on more insane engines!

[JustenGT8]

yea i found that aswell ,I think the toyota blowers are very poor in efficiency originally i had the idea to run the system in paralell, with a reflux valve, running the blower at a 3 to 1 overdrive thinking that it would only be running to around 4000rpm max,and wanting to get every last Rpm outa the blower, this never quite worked as planned tho, as the turbo would spool up compound with the blower wich was allready way overdriven and out of efficiecy and the turbo way chokeing up and doing all kinds of noises, back pressure was way up due to compressor only running around 3psi and big airflow way out in the chock flow, then the blower cluch would disengauge around 4000rpmand the car would take off just running on t66, no gd but could see the potential, geared the blower right down low boost 8-10psi, and added extra turbo. Turbos were running from 6-15psi into the blower. and intercooler, , this really performed much more nicely very smooth boost around 4000rpm ,postive inlet pressure to back pressure ratio, through the entire rev range, and seemed to just keep gobbling fuel the more boost and RPM you fed it

Positive boost to back pressure ratio is where it's at ....so poorly understood by many who just want to stuff in more boost

[RobV]

its amazing ,.alot of the top level people are only starting to use that tuning methology,

[mr75]

hey sorry for the stupid question but what do you mean rob by Positive boost to back pressure ratio? only so much boost to the back pressure your experiencing and if so whats the ratio? is it different for every turbo/setup or is there 1 general ratio?

[SeptemberSquall]

Performanceforums.com will also give you a warm reception.

"I've disconnected my factory BOV so it goes fuckenwhoosh lol, but..."

[JustenGT8]

hey sorry for the stupid question but what do you mean rob by Positive boost to back pressure ratio? only so much boost to the back pressure your experiencing and if so whats the ratio? is it different for every turbo/setup or is there 1 general ratio?

It's the ratio of exhaust manifold pressure to inlet manifold pressure. Most systems (OEM) aim for low boost response with not much thought for top end....generally results in a low ratio with exhaust manifold pressure higher than boost. This situation still drives a turbine but all the delta changes across the turbine are constrained. Efficiencies increase substantailly once than ratio approaches 1:1 and go thru the roof once they go greater than 1. A few of the turbo texts go into this and as with most pref mods it's a matter of compromise. The more effort in design though and the better your system will work.

[mr75]

It's the ratio of exhaust manifold pressure to inlet manifold pressure. Most systems (OEM) aim for low boost response with not much thought for top end....generally results in a low ratio with exhaust manifold pressure higher than boost. This situation still drives a turbine but all the delta changes across the turbine are constrained. Efficiencies increase substantailly once than ratio approaches 1:1 and go thru the roof once they go greater than 1. A few of the turbo texts go into this and as with most pref mods it's a matter of compromise. The more effort in design though and the better your system will work.

so its about having the right turbo, housings and wheel to suit your application? i have a gt3582 new but the ford xr6 spec with the 0.5 front housing and 1.06 rear. what do you think the efficenicy of this set up would be? or would this only be found by testing?

[big_zop]

While i never thought this was a good idea, i did stumble across this



And check out the exhaust manifold!


Here are the threads, although I havent had a good look through them so i dont know how much info is in them and the owner is from the Ukraine so his english isnt the best:
http://www.aeu86.org/viewtopic/ae86/...er=asc/start=0
http://www.hachiroku.com.au/blog/?p=270