Jump to content
SAU Community

Recommended Posts

I'm looking at extracting a bit more power out of GTR. After blowing the turbos at my first track day, I have done the following upgrades:

  • Installed Garrett -7's, dumps & front pipes
  • Vipec & tuned @ 260kw on 17psi (standard injectors)
  • FPR, pods, boost controller, exhaust already installed
  • Some other shit I can't remember :P

I would like to reach about 300-330kw safely, but more importantly I want the power to come on earlier. The turbo spools up between 3400rpm to 5000rpm. Is there any way to get it to kick in earlier? Aside from bigger injectors, what else would you guys recommend to get more power out of it without opening up the engine. Also, is there any advantageto switching to E85?

Cheers

Link to comment
https://www.sau.com.au/forums/topic/403940-getting-more-power-out-of-7s/
Share on other sites

  • Replies 85
  • Created
  • Last Reply

Top Posters In This Topic

Im pretty sure if your getting full boost at 5k rpm then you have something wrong or you have to go and get a different tuner.

Do the basic shit!

Bigger injectors

Fuel pump

Dump pipes

Big cat

Good exhaust

Mainly GOOD TUNER!

No reason why you couldnt get 300 if you do all that!

I also forgot I have a walbro fuel pump. What's the benefit of E85? I also should've mentioned this car is for the track only if that makes any difference.

I'm trying to find a dyno sheet from the last tune hopefully that will explain things a bit better.

cam gears

injectors

boost

tune

stock airbox

Whilst there are a whole swag of other parts you could buy... spending anything more realistically than the above list with those turbos, will not give you worthwhile gains for the money you'll need to spend.

I make around 300kw on that boost with -7s, and that boost hits at around 4000rpm. But you wont do it with stock injectors at stock rail pressure and stock cat/catback. So get 550cc or similar injectors, and a 100 or 200 cell metal cat and 3 or 3.5in catback. Cam gears can make the turbos spool earlier, and if you change them you'll need to tune, so you might as well get them now and have it all tuned together.

-7 come with new adjustable actuators, but they may need more pre-load. IIRC 10mm is a good starting point.

  • 4 months later...

Car is getting ready to go for a tune. At this stage I can't really afford switching to E85, so I was going to get a tune with the following items:

  • Bigger injectors (Bosch 750cc)
  • adj cam gears
  • tune
  • tomei poncams

Firstly, which type poncams should I go for? Secondly, are Bosch injectors any good? They're only $480 from ebay. And thirdly, are the cams useful in this setup? I probably should've mentioned the car already has 3.5inch exhaust and modified cat. Are there any other mods that might be more useful?

Thanks guys.

I don't know that much about the cams, from what i've read the poncam type b's would be suitable. Wait for someone with more knowledge to have a say on that though...

As for the exhaust, you mentioned you have done the cat and catback, by "modified cat" do you mean gutted? Cos if its a track car maybe you could just run a straight pipe in its place. What about front pipes? Those would make a big difference.

For -7s, no need for cams of some sort, stock cams are more than enough. Just need to arm it with adjustable cam gears.

On pump, -7s will do 300-330-ish kw at wheels depending on boost, motor condition.

The poncams are going to give you very little for a lot of expense - they're really a waste. Also, you shouldn't need to modify a cat...

If you dont get ~320 on 20-22 psi, then you have some troubleshooting to do. Eg, drop exhaust to check if its restrictive, compression check, etc.

Car is getting ready to go for a tune. At this stage I can't really afford switching to E85, so I was going to get a tune with the following items:

  • Bigger injectors (Bosch 750cc)
  • adj cam gears
  • tune
  • tomei poncams

Firstly, which type poncams should I go for? Secondly, are Bosch injectors any good? They're only $480 from ebay. And thirdly, are the cams useful in this setup? I probably should've mentioned the car already has 3.5inch exhaust and modified cat. Are there any other mods that might be more useful?

Thanks guys.

ditch poncams, new Walbro pump is like $180-190 i think? shove that in, and you're E85 ready - you've got everything else, and if you're going to get injectors, just get some 1000's and be done with it, although i think you'ld be ok with E85 and 750's. And it's a track car, even more reason to go E85, so much more protection available via the fuel.

the "can't afford" line doens't really make any sense?

the "can't afford" line doens't really make any sense?

I keep forgetting they make injectors to drop in for E85. So fuel lines don't need to be changed for bigger fittings or anything? I was also told the tune costs about $1800 for a flex fuel.

I'll look into pricing, am keen to switch to e85 for sure.

Also, it has a walbro already installed :)

Doing a flex fuel tune can be done depending on the ECU you have,

ID 1000's are great for $700 odd delivered, Give Tu Speed a call, Don't forget you will need adapters to fit STD rail, Call Tuff car parts for a set.

stock dumps are good if you can your hands on R34 ones, FPR are really needed... So ive heard.

you say you have exhaust set up already, Make sure its a free flowing as possible, What are current specs do you know? Either way. Start with big injectors and a tune. Wind the boost up to 20 psi + and should be happy days.

I keep forgetting they make injectors to drop in for E85. So fuel lines don't need to be changed for bigger fittings or anything? I was also told the tune costs about $1800 for a flex fuel.

I'll look into pricing, am keen to switch to e85 for sure.

Also, it has a walbro already installed :)

The newer e85 400L walbro flows twice what your 342 walbro will. They are also designed to be e85 friendly and come with sealed connectors.

Bosch ev14 1000's can be had for $600 including the adapters and plug tails locally, with warranty. ;)

^ hence i don't understand the affordability aspect... you have to do these things anyway, or already have...

you don't need a 'flex fuel' tune - you said it's a track car, so just leave it on an E85 tune, simply.

'flex fuel' is ability to run any mixture of 98/E85 - required ethanol sensors etc, this is not at all needed from what the OP has posted. Just needs an E85 tune and happy days :)

Yeah you're probably right, spoke to a few tuners and looks like the way to go. Are the stock fuel lines an issue?

This is what I've costed for so far:

  • E85 tune - $1300
  • Bosch 1000cc injectors - $600
  • adj cam gears - not sure whether to get ISC $200 ones for tomei ones for $380
  • Walbro 400lt fuel pump - $275

Have I missed anything? Thanks for the help guys :)

Race Pace make some great adjustable cam gears, they modified the stock ones and from i understand, it's a more durable base to start from. You could go that route, you'd either have to see if they have any in stock, or just send them yours.

Red R racing probably could modify stock cam gears as well. No real $$ advantage over new, the ISC definitely seem cheaper than what i paid for RP to modify mine

stock lines are fine in terms of concerns about degredation etc (not an issue)

i'm not 100% if there is concerns with a 'capacity' issue? i'm wouldn't think there would be an issue - i made near 300rwkw on my prev GT-T with E85 and stock lines, 98 car. Still fine on high % ethanol after 4-5 years

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Similar Content

  • Latest Posts

    • This is for an RB20DET. Sorry for not including that. 
    • Welp, this is where my compression lands after my rebuild. Thoughts? I have ~6 hours on the motor. 
    • Well, after the full circus this week (new gearbag, 14 psi actuator on, injectors and AFM upgraded, and.....turbo repair) the diagnosis on the wastegate is in. It was broken. It was broken in a really strange way. The weld that holds the lever arm onto the wastegate flapper shaft broke. Broke completely, but broke in such a way that it could go back together in the "correct" position, or it could rearrange itself somewhere else along the fracture plane and sit with the flapper not parallel to the lever. So, who knows how and when exactly what happened? No-one will ever know. Was it broken like this the first time it spat the circlip and wedged itself deep into the dump? Or was it only broken when I tried to pry it back into place? (I didn't try that hard, but who knows?). Or did it break first? Or did it break between the first and second event of wierdness? Meh. It doesn't matter now. It is welded back together. And it is now held closed by a 14 psi actuator, so...the car has been tuned with the supporting mods (and the order of operations there is that the supporting mods and dyno needed to be able to be done first before adding boost, because it was pinging on <<14 psi with the new turbo with only a 6 psi actuator). And then tuned up a bit, and with the boost controller turned off throughout that process. So it was only running WG pressure and so only hit about 15-16 psi. The turbo is still ever so slightly lazier than might be preferred - like it is still a bit on the big side for the engine. I haven't tested it on the road properly in any way - just driven it around in traffic for a half hour or so. But it is like chalk and cheese compared to what it was. Between dyno numbers and driving feedback: It makes 100 kW at 3k rpm, which is OK, could be better. That's stock 2JZ territory, or RB20 with G series 550. It actually starts building boost from 2k, which is certainly better than it did recently (with all the WG flapper bullshit). Although it's hard to remember what it was like prior to all that - it certainly seems much, much better. And that makes sense, given the WG was probably starting to blow open at anything above about 3 psi anyway (with the 6 psi actuator). It doesn't really get to "full boost" (say 16 psi) until >>4k rpm. I am hopeful that this is a feature of the lack of boost controller keeping boost pressure off the actuator, because it was turned off for the dyno and off for the drives afterward. There's more to be found here, I'm sure. It made 230 rwkW at not a lot more than 6k and held it to over 7k, so there seems to be plenty of potential to get it up to 250-260rwkW with 18 psi or so, which would be a decent effort, considering the stock sized turbo inlet pipework and AFM, and the return flow cooler. According to Tao, those things should definitely put a bit of a limit on it by that sort of number. I must stress that I have not opened the throttle 100% on the road yet - well, at least not 100% and allowed it to wind all the way up. It'll have to wait until some reasonable opportunity. I'm quite looking forward to that - it feels massively better than it has in a loooong time. It's back to its old self, plus about 20% extra powers over the best it ever did before. I'm going to get the boost controller set up to maximise spool and settle at no more than ~17 psi (for now) and then go back on the dyno to see what we can squeeze out of it. There is other interesting news too. I put together a replacement tube to fit the R35 AFM in the stock location. This is the first time the tuner has worked with one, because anyone else he has tuned for has gone from Z32 territory to aftermarket ECU. No-one has ever wanted to stay Nistuned and do what I've done. Anyway, his feedback is that the R35 AFM is super super super responsive. Tiny little changes in throttle position or load turn up immediately as a cell change on the maps. Way, way more responsive than any of the old skool AFMs. Makes it quite diffifult to tune as you have to stay right on top of that so you don't wander off the cell you wanted to tune. But it certainly seems to help with real world throttle response. That's hard to separate from all the other things that changed, but the "pedal feel" is certainly crisp.
    • I'm a bit confused by this post, so I'll address the bit I understand lol.  Use an air compressor and blow away the guide coat sanding residue. All the better if you have a moisture trap for your compressor. You'd want to do this a few times as you sand the area, you wouldn't for example sand the entire area till you think its perfect and then 'confirm' that is it by blowing away the guide coat residue.  Sand the area, blow away the guide coat residue, inspect the panel, back to sanding... rinse and repeat. 
×
×
  • Create New...