Getting More Power Out Of -7's

[JimmyRickard]

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
  

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

[SiR_RB]

Bigger injectors

Adjustable cam gears

1 bar actuators

Bigger fuel pump

And screw 22psi into it

[Hadouken]

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!

[Super Drager]

No Cat

Poncams

Camgears

24psi

Big Injectors + Pump

E85

[JimmyRickard]

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.

[The Dan]

Benefit of E85 = everything you want and more

[R31Nismoid]

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.

[MrStabby]

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.

[JimmyRickard]

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.

[Serpandrew]

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.

[Count Grantleyish]

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.

[MrStabby]

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.

[SS8_Gohan]

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?

[JimmyRickard]

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

[sydking]

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.

[scotty nm35]

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.

[SS8_Gohan]

^ 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

[JimmyRickard]

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

[SS8_Gohan]

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

[mico]

300kw + 700kw shot of nos = 1000kw. done.