Jump to content
SAU Community

Recommended Posts

Hay ppl

just chasing some advice on head work and turbo selection for my gtr!

Brief rundown on the car/setup

r33 gtr vspec

26/30 (in process)

Rb 30 block (machined)

Nitto pistons

forged rods

ati 1000hp balancer

custom oil pump

arp studs etc

The bottom ends basically sorted i need advice on head work now

i had a gtx3582r with tial housing but ive changed my mind (due to paranoia mainly)

i want to build a twin lowmount setup to keep it stockish looking from the top!

Im chasing 500kw atw (2nd reason for losing the gtx)

Ive looked a bit through the turbo upgrade thread and a bit of research has led me to believe that the garrett gt2871 -10 (gtrs i believe) would be a good choice with ext gates setup!

OPINIONS PLEASE???

HEAD WORK!

Will this work?

I want the car the have a decent rev range so opinions also greatly appreciated!

Tomei type b cams

tomei cam gears

.5mm oversize valves

titanium valve springs

retainers

Valve guides

Required machining!

OPINIONS PLEASE??

What kind of lag would i expect with this type of setup?

I know theres prob heaps of other parts involved so if you were to build the head what eould you do in these circumstances!

Thanks heaps

Link to comment
https://www.sau.com.au/forums/topic/398361-need-some-guidance/
Share on other sites

  • Replies 83
  • Created
  • Last Reply

Top Posters In This Topic

Go back to a single!

What he said.

And dont bother with o/s valves, Just tidy up the ports and bowls, I am using the supertech valvetrain with o.s valves cut back to near standard, With the 37/88 on a 30 bottom end you will give nothing away to any twin setup in terms of response and low down grunt.

Just do it, you wont regret it. they can shove the twin turbo goatf**k where the sun dont shine.

Problem is - he is in Melb.

You need an arsehole that can take a firehydrant if the cops pull him over with that, and the likelyhood given how things are down here ATM is highly likely...

It's basically engine out, install stock motor and then re-reg with a different motor & start again. Fark that.

As Paul said look into the GTX lowmounts if you want stock-ish appearance, but the custom piping will mean it's really quite obvious.

Do not go near the -10s/GT-RS. Worst turbos you can possibly buy. I cannot think of one user who has taken them off, and regretted doing so - that's how bad they are.

Hate to say it but if you want to have a stock appearance about as much as you'll make is 400-440rwkw with HKS 2530s, and when I say stock, it'll look 100% factory.

Have a read/search of the main FI section. You'll see they are a surgy/laggy mess for the power they make. Totally mis-matched like the HKS 2540 of old.

470rwkw+ you ain't going to get outta stock appearance low mount setup

Only way is the GTX turbos, but its pretty obvious they aren't factory then and you might as well have a big single.

Just add a shot of nitrous if you wanna race it or whatever.

I'll be going rb30 soon. I'm running hks gt-rs 441AWKW @ 24psi on a rb26 full boost by 5000rpm on e85

Should be much more responsive with the rb30 with full boost around 4000rpm. I have no comp surge and will be running 28-30psi.

We will see what result will be, let see if I can make 470awkw with a stock low mount look :)

Edited by destrukshn

looks stock and 470rwkw+, sounds like a challange

I to am building a 30 with RSs ( though was looking for T618ZS ) and was aiming for 450, though I have seen a couple of poeple on this forum make 500rwkw+ from RSs

Dealing with the backpressure from the mismatched wheels when the exhaust valve opens is , I think, the key to making then work

Lets face it if you want 450rwkw+ that looks stock then pretty much your only option is RSs or T618Zs

if you really want to use those turbos, i wouldnt be asking on a forum for ideas on if/how to get it to work.

Youre better off going to a good builder with a reputation for making things work and ask them, hand over your $$$ because once youre up there getting the max out of something, its takes every little bit.

everything counts.

Piggaz and N1GTR are up to mid 400s with -5's, they have well sorted setups.

most people net mid to high 300s... its the setup as a collective

if you really want to use those turbos, i wouldnt be asking on a forum for ideas on if/how to get it to work.

Youre better off going to a good builder with a reputation for making things work and ask them, hand over your $$$ because once youre up there getting the max out of something, its takes every little bit.

everything counts.

Piggaz and N1GTR are up to mid 400s with -5's, they have well sorted setups.

most people net mid to high 300s... its the setup as a collective

Honestly, it really depends on the person, what they really want for the car. A lot of people on this forum are misguided to those who talk up the -5s. If you driven a -5/HKS 2530. Yes it is responsive but every advantage will have some kind of disadvantage. My opinion of the -5s/2530 is that it lacks top-end, by about 6000rpm it is about at its limits. This is coming from someone who had a pair of HKS 2530s. With a set of HKS GT-RS even at 9000rpm on my car they still want to keep going. Disadvantage is yes it is laggier than a set of 2530s. Circuit wise 2530s, Drag wise GT-RS.

Mix and match an RB30 with a pair of HKS GT-RS, i could improve the responsiveness of the car and probably still make more power than N1GTR and Piggaz. Actually i made 441AWKW on a 2.6l bottom @ 24psi none of this RWKW rubbish. The outright power was more than they made on their respective RB28/30s. Whether it was more drivable on the road - probably not.

With my RB30 to be completed in 3weeks, tuning will be done on both 98/E85 @ 30psi. We will see the response/power output compared to the -5's. ;)

So really it is up to you, my opinion is -5s aren't all they are said to be. Depends on your engine package and since you're going RB30, it won't be as laggy as those who are on 2.6l and cry about them....

Edited by destrukshn

. Actually i made 441AWKW on a 2.6l bottom @ 24psi none of this RWKW rubbish. The outright power was more than they made on their respective RB28/30s. Whether it was Faster - probably not.

fyp

Having an extra 20kws right up the top of teh rev range does not make it the better package when you are forever waiting for it to start moving forward

Dont forget both Paul and Steve made more power going back to -5s at less boost too from memory

iirc Steves RB30 still didnt see full boost until after 5000rpm, same goes for GTRNUR's RB31 with GT-RS'

Im sure they can comment to confirm

Either way, I'm not going to tell you your setup is no good, its up to the owner to setup a car how they like, and if you like the GT-RS' than that is fine, and I cant really talk because I'm 95% sure Im going to throw a T04R onto a 1J lol

Do you have a dyno sheet of the 440kw 2.6 run? or a time slip?

fyp

Having an extra 20kws right up the top of teh rev range does not make it the better package when you are forever waiting for it to start moving forward

Dont forget both Paul and Steve made more power going back to -5s at less boost too from memory

iirc Steves RB30 still didnt see full boost until after 5000rpm, same goes for GTRNUR's RB31 with GT-RS'

Im sure they can comment to confirm

Either way, I'm not going to tell you your setup is no good, its up to the owner to setup a car how they like, and if you like the GT-RS' than that is fine, and I cant really talk because I'm 95% sure Im going to throw a T04R onto a 1J lol

Do you have a dyno sheet of the 440kw 2.6 run? or a time slip?

I actually wasnt waiting forever to get it moving. Depends how you're driving e.g. if i was in 2nd gear going around a roundabout it will be laggy. But if i was in first gear at the lights, actually didnt feel laggy at all better yet it was quite similar to the 2530s. This is a 6speed R34 GTR anyway. No changing any diff ratios. Probably couldve outdragged N1GTR or Piggaz on a 2.6l :P

Lets see if i hit full boost before 5000rpm. My 2.6l would hit full boost by 5000-5500rpm. Not sure what is up with other builds on their respective RB30s. Dyno sheet below: Not power was @ all fours and not RWD as theirs. Either way someone can run my graph of RB30 HKS GT-RS compared to theirs and compare apples to apples. It is hard to compare when the run below was done on a 2.6l bottom and run on different dynos.

Dyno.jpg

Edited by destrukshn

I am not too sure as I didnt get a dyno graph with RPM. The redline for the car was 9000rpm so you can estimate if you like lol. As i said, the car was laggy if i am driving through the streets around on 2nd gear but if you drove from 1st and kept in on power. Was a monster! :P

Edited by destrukshn

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



×
×
  • Create New...