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just had my gt30 500hp turbo with internal wastegate fitted, my rb25 pulled 260rwkws at 20psi and 229 rwkws at 13psi. just wanting any feed back from anyone else who maybe running similar combo. car goes really hard now, even though im very happy with the results would upgrading my cams make any difference tp peak power or would the results be miniscule compared to the outlay and cost???? would be interested in peoples thoughts and opinions?

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I have a mate with a GT30 with the smallest ex housing (0.63) making 353rwhp at 19 psi on a FJ20. Engine standard apart from cams + pistons. He made this on pump fuel.

I think your car being a 2.5 has much much left in it. Fuel limits the FJs to about 350rwhp so you should make 430 rwhp no probs. Obviously you have problems with airflow into the engine and in addition maybe the tune is conservative. My advice for making the 430rwhp: Get some tomei cams and upgrade from those pissy 240 degree 7.8mm cams....they're holding you back enormously. Get some 270s and your power will be there.

I get my car tuned next week tuesday so Ill let you know how it goes.

exactly.

my 600HP GT30 - with the GT series wheel (6 blade) makes 270rwkw on 16psi.

So an int Gated version of the 500HP variety wont make anymore.

I'd be very happy wtih the result.

CAMS might get you a little, but stock 25DET heads are pretty good for 300rwkw with the stockers

There are .63 ARR housings and .63 ARR housings . If its the poor old Nissan cast T3 housing reprofiled your on your own . This combination is known not to work properly . Garrett does make a proper .63 version of the GT30 84 trim housing which works well on FJ20's . If you must have an integral waste gate housing HKS do them in .68 and .87 for the PRO S version of their GT3037 which is the same CHRA as the GT30R and has the T3 flange . These housings are expensive but cheap compared to external gates and custom manifolds and good enough for the street .

My opinions cheers A .

Yes , that CHRA in Garrett speak in Pt no 700382-12 for the same thing . Some Garrett BB CHRA's need the locating groove machined 1-2 mm deeper into

early HkS housings but its a std thing nowdays . There was once a string at a US SR20 site about someone using one of ATP's (Garretts) GT3071R's in a T28 flanged .73 ARR HKS housing and it needed this mod . In that case the 3071R CHRA was being substituted for a damaged 3037 core so the original assembly was an early build HKS turbo . 90% of them go bolt .

GCG said they can get them for about $800 though I enquired some time ago . These use HKS's GT Pro outlet on the back so you may need to make a dump pipe for it .

Cheers A .

I have a mate with a GT30 with the smallest ex housing (0.63) making 353rwhp at 19 psi on a FJ20. Engine standard apart from cams + pistons. He made this on pump fuel.

I think your car being a 2.5 has much much left in it. Fuel limits the FJs to about 350rwhp so you should make 430 rwhp no probs. Obviously you have problems with airflow into the engine and in addition maybe the tune is conservative. My advice for making the 430rwhp: Get some tomei cams and upgrade from those pissy 240 degree 7.8mm cams....they're holding you back enormously. Get some 270s and your power will be there.

I get my car tuned next week tuesday so Ill let you know how it goes.

hey dude,

just wondering, do u feel that the GT30R is laggy on the street with the A/R .82 exhaust housing?

when do u roughly get full boost?

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