Time For Some Upgrades

[QWK32]

Finished off a couple other things. Made up some heat shielding for the new turbo as you cant use the stock heat shield. I used some ceramic cored aluminium sheet, its about 3mm thick and apparently good for around 800-900c. it was really easy to work with and form. it seems to be doing the trick, the cables and pipe work in the corner with the abs aren't getting as much heat soak anymore.

today i also got around to installing a new set of coilovers which i desperately needed. on my recent trip up to my brothers, 400km away, with 4 adults, luggage and not the best roads, i managed to blow out the rear left shock and the right hand side was starting to leak. i wasn't too fussed as i had some new ones to go in, and considering it was still the 10 year old stock suspension, i wasn't surprised.

i set the new coilovers to 50mm lower than the stock ones, which only gave me about a 25-30mm drop all round (i was expecting this), fronts are the same height left to right, but in the rear, the side with the fuel tank sits slightly lower than the other, i'll fix this up tomorrow. Give the springs a few days to settle then drop it down some more and off to get the alignment checked. i'll be getting some adjustable camber arms or bushes this week to allow me to drop it and still get a good setup.

[DaveB]

Looking good Josh! Will be interested to know what your dyno graph looks like when you've finished tuning. Roughly what horsepower is your GT35 capable of?

[KiwiRS4T]

Which exhaust housing do you have (using .63 on mine)?

[QWK32]

Looking good Josh! Will be interested to know what your dyno graph looks like when you've finished tuning. Roughly what horsepower is your GT35 capable of?

yeah i'm keeping my eyes out for a dyno day or any opportunity to get it on one to see how its going. i first tuned it to 14psi as i had a couple other things to sort out, just recently i've tuned it up to 20psi so i'm keen to see what power its making. the GT35 is rated 400-600 hp. i want to see it around 400hp to start with, then once i forge the engine, go for more.

Which exhaust housing do you have (using .63 on mine)?

i'm using the .82 internal gate housing.

[dirtyRS4]

yeah i'm keeping my eyes out for a dyno day or any opportunity to get it on one to see how its going. i first tuned it to 14psi as i had a couple other things to sort out, just recently i've tuned it up to 20psi so i'm keen to see what power its making. the GT35 is rated 400-600 hp. i want to see it around 400hp to start with, then once i forge the engine, go for more.

i'm using the .82 internal gate housing.

nice. but with running that amount of boost and 400hp, your'e really pushing the stock internals to the limit. i would also recommend a 1.8mm head gasket.

[DaveB]

Had I my time over again I'd have stuck with the stock pistons and gone for 500hp and waited until something broke, *then* rebuilt lol...

Josh what is the boost build like on a GT35? My GCG highflow is pretty much as responsive as stock but makes more power everywhere. I would like something that will make real power though...

[QWK32]

nice. but with running that amount of boost and 400hp, your'e really pushing the stock internals to the limit. i would also recommend a 1.8mm head gasket.

i've seen plenty of examples and personally know of a few engines running that sort of power on stock internals and they continue to do so safely. i've been running this setup for over a year now, and 20psi for a little over 6months and the engine still has good compression and runs nice and smooth. i know where your coming from when mentioning the thicker head gasket, but i'm not too bothered about it, 20psi is still be ok on the stock one and i'm not too keen on opening the engine before i'm ready to do a forged rebuild.

Had I my time over again I'd have stuck with the stock pistons and gone for 500hp and waited until something broke, *then* rebuilt lol...

Josh what is the boost build like on a GT35? My GCG highflow is pretty much as responsive as stock but makes more power everywhere. I would like something that will make real power though...

Dave the GT35 is a completely different power delivery, i imagine yours is a smooth increase in power, the GT35 hits hard, like doubling your power in a second lol. i get about 5-7psi from 2500-3000rpm, which i would compare to the same feeling as a stock turbo on 10psi. i get a slight increase in boost, maybe 5psi then as the revs increase until it hits hard at about 4000rpm. i have lifted my rev limit to make use of the later onset of power. it is a laggy turbo but that how i like it, not once has it annoyed me to the point where i wanted to replace it. it is a bit slow off the line but once power is on, with the auto, it will hold through the gears.

it depends on what type of power curve you like Dave, the GT30 is popular, a little less laggy and will still get you too 400hp, i probably would have gotten one if the GT35 and associated parts didn't come up so cheap (i got it off a friend). hi flows are good as they retain stock turbo response and give more up top, which is good for people who dont want to sacrifice a bit of low down for more up top.

i also wouldn't mind trying the .63 rear housing to see how that performs compared to the .82, but it all costs money and i cant justify shelling out $1000+ to try a different house that might not make that big of a difference anyway.

Edited December 23, 2010 by QWK32

[KiwiRS4T]

Here is a quote from a workshop owner in Wellington:

A basic example of somthing we have tested at work.

RB30DET, usual standard mods, GT3582R. with a .63 on 14psi it made 300kw. with a .82 it made 330kw, though boost came on 500rpm later.

On 18psi the .63 made 350kw, where as the .82 made 375kw (could have made more but the power was more then enough for a street car)

The owner with the .82 exhuast housing, is looking to down size as the car isn't as responcive as he would like 4000rpm full boost.

That's on an RB30 but I guess the principle would be the same - changing to a .63 housing will bring boost on about 500rpm earlier and cost you 35kw at the top end.

I guess if you are used to how your car drives now there is no need to change but if you did want to change you could probably find some one with a .63 housing who wanted more top end and do a swap!