The Tuning Talk Thread - Forced Induction EFI & JZ Tuning.

[VA61DETT]

Been following this thread for a while now.
Some really useful info accumulating.

Out of curiosity has anybody done the numbers for a moderate twin upgrade for a 2JZ?
Since I am running a VG30 (don't hate me!) they should be fairly similar in air flow.
I have been looking at getting a pair of faster spooling GT25 to 28's.
I am aiming for about 400RWHP & after response over absolute power.

I plugged in my numbers (for 1.5L) here:
http://www.lovehorsepower.com/joomla...id=4&Itemid=88

And came up with a plot here:


From what I can gleam it looks like a fairly good match, but wont go much higher then 20psi before choking.
Dose this look about right?
I kind of figured a GT28 would be a little large for effectively 1.5L, so I am not sure if I ran the numbers correctly.

An input would be much appreciated.
Cheers.

[sleepercorty]

long term i want it to be stupid... well maybe not stupid but in a ballpark of 600rwhp

wifes supra has a 35r on a 2jz for lightning quick lightswitch response...

as far as turbos go ill probably stick to the garrett range due to its long time proven track record...

the precision and such look like a good bit of gear but for some reason i think i want to stick with a trusty old garret for futur mod path...

check out my cressida build thread i did a test between garrett t66, garrett to4z and a precision turbo of the same size precison definately came out on top. to4z ran out of puff on my 1jz at around 30psi made best of 560rwhp, precision turbo made 600rwhp on the same boost and still makes plenty more power after 30psi

[midnight_purple_GA70]

ill have to take a good look when i get a chance... seems that i will one day need to rethink my plans if i want to go for big power...

[boxh34d]

VA61DETT:
I would have thought that your 3L should be able to get that kind of power @ less flow. 400RWHP, should only take around 25lb/min per turbo (around 500 engine HP).
Without being familiar with your engine, by my quick calcs, around 25lb/min per turbo, @ 18psi and 6500rpm should put you about where you need to be. I would not expect you to be able to make max power much higher than that unless your engine has some cams or something to help it breathe that well up to 7500rpm.

Have you had a look around the Z forums, as I'm sure that this kind power level would be well documented for you to compare.

[VA61DETT]

-boxh34d

Cheers for the info,
I have been looking all over, but I have had a little luck on finding decent info.
Hence posting here, since people seem to know what is what

[Ken_T]

Hi guys, I'm trying to retune a 4agte at the moment but i'm having some trouble. Car was initially tuned with a 8.0:1 comp big port gze with an s14 t28 and everything went fine. New motor is an ae101 gze (smallport) and we're retuning to suit.

Got the fuel map sorted out to good enough but it's still pretty rich because of the issue we're having. I've only spent 20 minutes or so on it but I can't get it to stop "knocking". I've put knocking in inverted commas because as much as it sounds like detonation I don't believe it is. Basically, anything above 80kPa between 2-4100 rpm sounds like pinging. I'm using a wideband Nissan knock sensor bolted to the block in the middle of cyl. 4, running to either an amp then to my noise-cancelling headphones or through the laptop to record the noise and to the headphones without the amp. AFR's I think are around 11.3-4 when this occurs.

The recorded sound is in the right range estimated to be knock for this engine. I bandpassed the recording between 5500 and 7kHz and the noise is more prominent. I've had the timing as low as 4 degrees in the 100kPa/2500 rpm cell and the noise is still there. Dropped like 6 degrees between two adjacent cells that knock and the noise stays the same.

Here's the kicker, once you get past 4100 rpm, the knock disappears. You can set the timing above that cell like a normal engine and no knock whatsoever.

Out of boost you can rev it through the knock rpm range without a hint of knock.

This has got me stumped. The only thing I've checked atm is cam timing and timing with a gun to make sure the number on the laptop is what's actually happening at the engine.

Halp!

Edit, I can email over the tune file and recorded sound if anyone wants to look over it/listen. Ecu is adaptronic e420c.

[JZA70 R]

There is a live webinar on right now where Andre from 'High Performance Acadamy' is teaching Nigel from 'Engineered to Slide' (Melbourne) how to tune his recently finished drift hilux. Its a SR20 with a TD06 20g running pump 98... The ecu is a Link G4 storm.

HPA speaks with Nigel Petrie from Engineered to Slide on Livestream

[BEVANI]

Hey toymodders need a bit of help,

Im currently running a 1jz with haltech PS2000 and haltech HPI6 ignitor

Anyone running a similar setup and can anyone shed light on the config and settings to make it start?

trial and error and multiple attempts at starting and no luck. i just need it running prior to sending it to my tuner
All wiring has been double checked and wired correct, ive confirmed that the home and trigger are wired correct as im receiving a steady #24 TSLH and RPM signal, and yes running off the front cam sensor, also getting spark on all cylinders
Im still concerned ive got the numbers wrong for the trigger and home signals, in the config crank angle @65 degrees tooth offset of 22 timing currently locked @10 is there anything ive overlooked?

also does anyone know what the dwell time is on the factory coils?


Cheers in advance for any help!

[JP]

So you've confirmed the timing reads 10deg at the crank with a light?

What's the rpm reading when cranking? 150-250rpm?

[BEVANI]

yep RPM is between 160 and 200 RPM ive got to double check the timing as i think i busted my timing light today so ill have to get back to ya on that

the motor was running prior to the install so nothing has changed or moved internally..

[BEVANI]

Ok so i got all the timing set and locked @10 degrees for starting but still no go. im using the haltech base map for VE tuning so base values for fuel are @55% and ignition is 10deg

still getting the odd backfire usually when stopping but no starting, i have found the plugs after several attempts are black and sometimes wet so im guessing over fueling? what is the best option on spark plugs and gap? higher heat range maybe required?

[JP]

Ok so i got all the timing set and locked @10 degrees for starting but still no go. im using the haltech base map for VE tuning so base values for fuel are @55% and ignition is 10deg

still getting the odd backfire usually when stopping but no starting, i have found the plugs after several attempts are black and sometimes wet so im guessing over fueling? what is the best option on spark plugs and gap? higher heat range maybe required?

Engines start easier rich than lean. Try 80% for fuel or double check your cranking/startup enrichment

[JP]

edit: double post

[BEVANI]

thanks JP ill give it a try, im going to clean the plugs this morning first... only concern is that its quite cold outside even in the garage, anyone have any extra tricks for cold/er starting?

[BEVANI]

Winner!
Plugs were black and fouled, changed to a set of BKR6E's....BAM! started first go... AND the 2nd time round also!

now i have to fix a leaking turbo oil inlet and a few small things... then Dyno time..

Thanks for the help JP!