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Was having this conversation with a friend the other day about some of the weird stuff we have seen on jap imports and especially those that were freshly imported. Fairly interesting to hear and see some of the stuff that use to be done when turbo/injector/ecu upgrades were expensive.

Personally i have seen:

A Z32 300ZX with a secondary fuel rail ontop of the plenum with 270cc injectors(Z32 NA).

Another Z32 with Fuel injectors in the intake pipes and Mines ecu.

A mates R33 GTSt with a Fuel cut defender, stock ecu & afm, HKS Gt2540, Old school Trust return flow cooler, FPR, 20psi and timing retarded via the CAS. I thought the car would run like shit but it trapped 114mph iirc at WSID.

Another R33 GTSt with a HKS GTRS, Mines ecu and again timing retarded via the CAS.

So just curious what you guys have seen?

Twin injectors per runner was used in the YB Cosworth Sierra RS500, although the second rail was inactive for road/emissions.

The old 2 litre Supertourer Audi A4 also used twin injectors.

Prior to easily flashable ECUs, it was relatively common to see overall enrichment via a potentiometer on the coolant sensor. Made the ECU think it was still in warm-up mode and push more fuel in.

I don't know if you guys got the 4G63 Mitsubishi VR4s, but they were all the rage in the late 90s/early 2000s here and there was a trick where you could "swap the hoses" which really looking back was probably just messing up the feed to the wastegate and potentially freeboosting them. Typically only done for "drags" and I actually don't know anyone who melted an engine doing this, and the intended result was always reached - they went HEAPS better when this well considered mod was performed. I think one of the guys cracked into the 11s with one just by stripping it out, upgrading the fuel pump, putting some AVGas in the tank and giving it the freest flowing exhaust they could.


Similar to the other mods mentioned here - there was a spate of guys who turbocharged their Hondas back then too, typically making up a shitty exhaust manifold, attaching an EVO or WRX turbocharger, a cheap intercooler, retarding the timing slightly and hooking up an extra injector in the intake which is triggered by a pressure sensor. Again these lasted surprisingly well!


On the flipside I remember back in these days (we're talking mid/late 90s) realising I maybe didn't fit into the V8 world of the day as well as I fit in with Japanese tuning - I had what actually turned into a fairly heated arguement (yay bourbon) about intercoolers being a gimmick. The V8 guys (and actually quite a few people general car people) were CONVINCED that they were just a passing ricer fad and if anything they cost power, and generally anyone that condoned it or did it were retarded.


Its quite interesting watching tuning ideas and understanding evolve over the years :)

Jpc in vic, for some vl turbo setups, used to run 2 commordore ecus and two set's of standard injectors.

Extra injectors, dodgy wmi setups with copper tubes that would gunk up and washer bottle motors., timing always retarded by cas, where typical stuff. Some of its clever how they got around things, some is dodgy.

In american with the jza80 supras they have BPU mods. Back in the day, you'd pull out the headlight(worth2-3mph), drop the exhaust at the turbos , run race fuel and reset ecu to stop pulling timing, and pull the actuator hoses of the twin turbos.

For no money you had a 11 sec-low 12 118-120 ish mph car

cheers

darren

Edited by jet_r31

Yeah i've heard of JPC before, came across this video that i thought was interesting. 418rwkw out of a T3 based Highflow on E85, Maybe Hypergear can enlighten us as to what core is in this turbo.

looks like a 3582 or equivalent in .63 turbine housing, which should be enough to flow that sort of power.

That engine would've had extensive head and cam work, But I'm no Rb30 expert.

haha..you think?...i was always going to ask you about this...It has a standard nissan vl comp cover..so same comp

cover as standard Rb25 turbo..can you squeeze a 60mm comp wheel in a standard comp cover?...and next, thats 418rwkw

through a AUTO...and thats dyno ..on that ramp rate... probally reads 40-60rwkw less than the dyno you use stao...and then the

auto probally reads another 40rwkw less than a manual..

Car hasd run 140mph..punch that in, its nearly 680 ish hp at the crank...still think its a 3540 .63...because i know my rb30

single cams and you would struggle big time with a 1.06 housing to even get within 30rwkw of that...

everyone would love to know what it is..lol

cheers

darren

Edited by jet_r31

sorry, wasn't meant to be confrontational at all, just given stao a bit more info and wondering if he still thinks that,

he knows his turbos, i genuinely would like to hear his thoughts, as it has me stumped unless they are bullshitting.

fuel is E85, no gas. I reckon going by most jpc stuff it would be borgwarner parts fitted

cheers

darren

haha..you think?...i was always going to ask you about this...It has a standard nissan vl comp cover..so same comp

cover as standard Rb25 turbo..can you squeeze a 60mm comp wheel in a standard comp cover?...and next, thats 418rwkw

through a AUTO...and thats dyno ..on that ramp rate... probally reads 40-60rwkw less than the dyno you use stao...and then the

auto probally reads another 40rwkw less than a manual..

Car hasd run 140mph..punch that in, its nearly 680 ish hp at the crank...still think its a 3540 .63...because i know my rb30

single cams and you would struggle big time with a 1.06 housing to even get within 30rwkw of that...

everyone would love to know what it is..lol

cheers

darren

the engine's not standard

From the video description:

the car uses a std exhaust & inlet manifold and a std throttle body

Engine has rods, pistons and a hydraulic cam upgrade.

If you count the time of when its stepped into gas the dyno ramp seems to be 16secs.

Factory VLT Comp housing is smaller then skylines, You can see the comp housing in this video is larger.

GT35 rear end should be able to flow that easily, and work well with long ramp. since its internally gated the comp wheel should be some thing around a large trimmed 76mm or a 82mm wheel in a .70 housing.

Just my prediction of what the highflow profile might be. Never knows, I don't have personal experience with VLTs.

Mod your VLT identical to the one in this video, send me your stock turbo and it doesn't take long to figure it out :yes:

you sure you can see the comp housing in the video??, i cannot see it. (i watched it twice maybe im blind..lol)However i have seen the car in real life at the track and it looks

like a standard vlt comp cover and then i saw it pull 139mph , apparently on only 30psi..if the cams hydraulic(which im guessing it is as i havnt seen a modded rocker cover, then its probally a tx2, [email protected] ish lift 117lsa

cheers

darren

Edited by jet_r31

Stock VLT should be some thing like .46, Skyline is in .60. There is no way you can run 30psi out of that. to handle 30psi it should have anti surge slot as well.

Let me know when you want to work on your VLT. I got some thing in mind that should make same power with lot less boost.

From a thread on the VL forums

"Car has actually made 410rwkw @ 35psi but was raced on 31psi due to
complications, but i believe it will go out with 35psi next time"

And also

Edited by Super Drager

I'm currently building a 13s for $ 1300 car with an rb20 auto s13.

For tuning i have a wideband.

I'm using jaycar digital fuel adjuster to pass fuel cut

boost fuelling with an adjustable fpr and pontiometer on water temp sensor

And using the cas to advance or retard timing as required

With a r33 turbo with vg30 housing i expect to see 180kw atw or so

The digital fuel adjuster also has a relay output for additional wmi injecton, fuel pump etc so i may utilize this feature if i upgrade the turbo

Its ghetto tuning at its finest but this stuff works.

gotta remember that E85 is really a wonder fuel so i have heard.

I had a KE TX3 Turbo back in the days that had a Boost cut and fuel cut but what you could do is just DC the boost cut pipe and block it and you could run as much boost as you wanted with the bang bang of the engine cutting also it was only mapped up to 11psi so i stuck it at 10 psi from a stock 8psi on a Hi flowed VJ14 turbo.

also seen a extra injector setup on another TX3 just 1 extra 550cc RX7 injector that was hook up to squirt when number 1 injector did work well until the bonnet was up and it was spraying fuel everywhere wasnt sealed could have been a huge fireball was in the rubber inlet hose.

Edited by HYBRID VL

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