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I got a GT30r with a VG30 back end on it... I hope to make about 270rwkw on about 14psi-15psi... You think this is possible? The GT30r has a .7 compressor cover and is rated at 550hp. The brand new core, cover and VG30 fitted to the back cost me $1300.

Running an excellent exhaust and intake, fuel pump, 550cc nismo's and getting tuned with a powerfc and a datalogit...

You think I'll push 270 rwkw?

Edited by The Mafia

The Mafia: I wouldn't know :(, best ask someone in the trade.

There are a few "hidden" mods to acheive that figure, so it is not a case of just bolting up a vg30 ext. housing. I just love the combo because the turbo and eng. still appear to be standard.

The Mafia: I wouldn't know :D, best ask someone in the trade.

There are a few "hidden" mods to acheive that figure, so it is not a case of just bolting up a vg30 ext. housing.  I just love the combo because the turbo and eng. still appear to be standard.

Yep you wouldnt want others to thing by strapping the same turbo on they are gonna get the same power figures.

Very surprising tho that such a small turbo is making so much power with only 15psi.

How much did you spend on head work? :(

All up about $3k on head work. That included; r33 s1 Tomei Poncams (256-duration, 8.15-lift), race porting, valve springs, full reco and clearances, cam gears, etc.

Ash: This graph was not the final tune as we acheived the goal and lowered the boost to keep the bottom end safe, at 255rwkw. He actually had to back the timing off in this rev range as with his headphones (Forget the name, but the tool used to listen for detonation) he started to hear some slight pinging. He couldn't explain why it happens, but claimed that he has also noticed it on other rb25's. The only common factor is the inlet plenium, as he has tunned other rb25's with aftermarket pleniums and has not had this problem. Not sure if more tunning/dyno runs would have been able to eliminate the fault, but as stated previously we didn't want to push the std bottom end to much.

i'd be skepitcal if a plenum would have anything to do with that :P

Mine doesnt have a problem, Denham's doesnt either.

Jeff in WA using a wolf also has 297 out of his so far :)

you could back it all out a tad more and then give it more of a mid range and then it.

Can not understand this part.......... :mellow:

you could back it all out a tad more and then give it more of a mid range and then it.

I have to agree with you, but as stated, we didn't bother cleaning it up as my goal was to keep it at 250-260rwkw. Vic cleaned it up a little more after this figure was recorded, once he lowered the boost to only acheive about 255rwkw. But i didn't bother getting a print out of this graph :( .

We haven't as yet played with the adj. cam gears (in and ext), this will be done when i desire more power and that wont be till i do the bottom end.

All up about $3k on head work.  That included; r33 s1 Tomei Poncams (256-duration, 8.15-lift), race porting, valve springs, full reco and clearances, cam gears, etc.

Ash: This graph was not the final tune as we acheived the goal and lowered the boost to keep the bottom end safe, at 255rwkw.  He actually had to back the timing off in this rev range as with his headphones (Forget the name, but the tool used to listen for detonation) he started to hear some slight pinging.  He couldn't explain why it happens, but claimed that he has also noticed it on other rb25's.  The only common factor is the inlet plenium, as he has tunned other rb25's with aftermarket pleniums and has not had this problem.  Not sure if more tunning/dyno runs would have been able to eliminate the fault, but as stated previously we didn't want to push the std bottom end to much.

Looks like a good 3k spent there. Where does she start to make good power from?

Ash u never got any head work on ur with your rebuild did ya?

Looks like a good 3k spent there. Where does she start to make good power from?

Ash u never got any head work on ur with your rebuild did ya?

All depends on the gear your in.

I am not sure, as things get pretty exciting once power comes on (as you would know, with your car), but in second gear i would say about 3-4k rpm

I can not speak highly enough of cams and head porting, i strongly beleive that such good results are not possible with the std head and this turbo.

Denham just think how much potential is still untapped, from your turbo, because of the std rb25 head. If you ever consider a rebuild seriously think about head work.

I can not speak highly enough of cams and head porting, i strongly beleive that such good results are not possible with the std head and this turbo.

Denham just think how much potential is still untapped, from your turbo, because of the std rb25 head.  If you ever consider a rebuild seriously think about head work.

yer i being hopful of numbers close to that but i strongly agree with you about the head work if i pop it any time it will probably get the full treatment but at the moment i'm just spending a few grand on the bolt on stuff to give it that bit more.

Looks like a good 3k spent there. Where does she start to make good power from?

Ash u never got any head work on ur with your rebuild did ya?

Good power around 5000rpm, did you even look @ the graph denham :mellow:

Nope, 100% factory Nissan RB25 head :(

The head in its stock form is pretty good upto around 300rwkw from what ive seen by a good number of cars now.

I could have gotten some done, but its a cost that wasnt justified when i could just mash another 1-2psi down there :D

AL, what i mean was, if its pinging or whatever where timing is being pulled, which i dont think it should really be doing...

backing off a bit earlier on would result in a wider band rather than getting to a point where the graph stops heading up @ the great rate... on to slow and then only to get back on the climb again later on.

I can not speak highly enough of cams and head porting, i strongly beleive that such good results are not possible with the std head and this turbo.

Denham just think how much potential is still untapped, from your turbo, because of the std rb25 head.  If you ever consider a rebuild seriously think about head work.

Yep i know there is still alot be be gained with my system.

When the engine does finially get rebuilt it will get the works, which is gonna cost alot of $$ that i am not prepared to spend on it at the moment.

Missed out on the 19 mil on the weekend also!!!

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