Pelican Parts Forums

Pelican Parts Forums (
-   911 / 930 Turbo & Super Charging Forum (
-   -   Initial impressions on GT35R BB Turbo & GSF Headers (

WydRyd 11-15-2006 01:24 PM

Initial impressions on GT35R BB Turbo & GSF Headers
Thought this write-up deserved a thread of its own, for anyone who's considering this path.

I picked up the car last night and I must say, it's a totally transformed BEAST now :eek:

The pre-boost torque and drivability with the GSF headers & GT35R BB turbo is amazing. This turbo is a MONSTER guys :cool: When it spools, it whistles VERY loudly, almost to the point of scaring me from applying further throttle :confused:

The last few days have been quite wet down here, so I haven't really had a chance to get a feel for what this new setup can do, but my initial impressions are that it will meet and probably exceed all my expectations.

I'm not too sure about the SPEC Stage3+ clutch as yet. It's new, so I guess it needs proper breaking in, but I'm not very familiar, or use to, the on/off feel of this clutch. I'll give it a few months and see how it goes.

The Magnaflow single out muffler sounds great. Not TOO loud and not too quiet. Again, I haven't applied full throttle yet to experience the whole system, but I like the sound of the Magnaflow and the build quality and welds are of a very high quality.

I was quite surprised that the GT2 EVO CAMs don't sound as lumpy with a proper header setup & the GT35R. The older K27HF and factory heat exchangers made the engine idle quite lumpy, but now it's very smooth. Probably because of the more efficient exhaust flow and split/divided housing on the new turbo?!?

I can't wait for some dry weather this coming weekend so I can experience this new configuration completely :cool:

I'll get & post some pics when the weather dries up ;)

P.S: I'm not even running an optimum tune with the Proto Motronic Stage3 CHIP. Once I go MAP sensing, it'll compliment the setup even further. Oh, another cool thing is you can hear the compressor still spinning after the engine is turned off ;)

hobieboy 11-15-2006 06:23 PM

Congrats!!!! It is certainly a great feeling when everything works out, or better than what you expect :D

Are you running with a 3.4 set up? Are you EFI now? What BOV are you using - kinda interesting that you can hear the turbo when you shut off :)

WydRyd 11-15-2006 06:31 PM

Thanks ;)

My setup is an aftermarket turbocharged Carrera motor, with 930 P&C's, GT2-EVO CAMs, ARP fasteners, racing valve springs, titanium retainers, turbo spec inlet/exhaust valves, C2T head gaskets, full bay IC, twin plugged heads, OEM Motronics with Protomotive software & FPR. BOV is a TiAL 50mm, W/gate is a TiAL 46mm unit.

Yeh, I can hear the compressor winding down after a shut-off, through the air cleaner. Probably spins down for a minute or so :)

Lukesportsman 11-15-2006 06:47 PM

We wait with anticipation. Glad you finally committed to a route and achieved your expectations :) Very nice Merv, and yet my misguided path continues....ever since some deal fell through with a nice Australian gentleman in a bolt on setup.

WydRyd 11-15-2006 07:02 PM


Originally posted by Lukesportsman
We wait with anticipation. Glad you finally committed to a route and achieved your expectations :) Very nice Merv, and yet my misguided path continues....ever since some deal fell through with a nice Australian gentleman in a bolt on setup.
Thanks Luke. The power from this single setup certainly meets my expectations. I actually think it may be TOO powerful as an everyday car, but hey, who's complaining :D

My only gripe is with the SPEC clutch... that thing is a b!tch to engage smoothly, but I'm getting use to it, and I hope it improves as it gets bedded in :confused:

Are you still going down the TT path? My Proto TT kit is still available mate ;) :D SmileWavy

hobieboy 11-16-2006 06:11 AM


Originally posted by WydRyd

Yeh, I can hear the compressor winding down after a shut-off, through the air cleaner. Probably spins down for a minute or so :)

Wow - maybe its because of the straight pipe that I used (too loud :D). I bascially connect a K&N directly off the turbo inlet and I still can't hear it wind down when I shut off the car; though I do always idle for a minute or so before I shut her off, so maybe the turbo had spun down by then? :confused:

BTW - do keep us posted when you have a chance to truly test her capability :)

rsrfan 11-16-2006 08:11 AM

Remember guys, he is running a Garrett ball bearing turbo - it is the ball bearings you hear after shutdown. They do sound cool.


Lukesportsman 11-18-2006 04:33 AM

Yes, Merv still thinking TT. Already have too many parts at this point to go Protomotive and I ended up with a 3.0 base at this point and Megasquirt. Decision are snail size and whether to go to the trouble and cool factor of ITB's or just slap on a Carrera intake (both in the garage, don't tell wife :) )

rs911t 11-18-2006 06:27 AM


Originally posted by rsrfan
Remember guys, he is running a Garrett ball bearing turbo - it is the ball bearings you hear after shutdown.
FWIW My K27HFS blows air for a few moments after shutdown.

WydRyd 11-19-2006 02:09 PM

UPDATE: I tried to test out this new setup on the weekend and had a couple issues.

1. First time I tried to cane her, the vacuum line blew off the fuel pressure regulator :mad:

2. Once I tracked THAT down and fixed it, took her for another spin and found that when boost kicks in hard, I'm experiencing ignition break-down :mad:

Time to fit that Crane HI-6 ignition system back in there :confused:

quattrorunner 11-20-2006 03:55 PM

Turn the boost down a notch.

WydRyd 11-20-2006 05:20 PM

Yeh I could, but that'd mean I'd have to go inside the w/gate and remove one of the springs (it has a 0.8bar + 0.3bar spring in it).

Probably just as much effort to install the Crane unit and leave it at 1.1bar.

beepbeep 11-20-2006 11:50 PM

As I said before, I firmly believe that removing 0.3 bar spring is very prudent thing to do. You can raise the boost from 0.8 by other means. You might run into trouble on firm 1.1 bar if it's really warm outside and you hit a batch of bad gas.

WydRyd 11-21-2006 01:19 PM

Hi Beep! Interestingly, this morning was quite cool and I gave her a bit of throttle. Seems like the wastegate was supplied with a 1.0bar spring. My telltale boost guage shows it pinned right at @ 1.0bar and I got no hesitation up top. What I may have experienced on the weekend was possibly due to the warmer weather :confused:

Either way, I'm typically seeing full boost by 3K on a pretty crude tune, so I'm happy with the end result. I can't wait to go standalone EMS and twin plugs now, to further improve on an already great setup.

I highly recommend the GT35R to anyone considering an alternate path... Heck, I'd be willing to try the GT30R for high performance street. I think the GT30R would be a seriously fun street turbo, seeing that the GT35R provides this level of drivability and responsiveness.

Porschefile 11-22-2006 04:39 PM

Merv, full boost at 3k? How much boost and what size hotside? Is it a t3 or t4 hotside. Hmm, that sounds like some pretty quick spool! That has me considering selling my Billet Design Marco Manzie headers and going with the GSF ones as I'm no longer interested in going the high hp dyno queen route. ;)

WydRyd 11-22-2006 06:04 PM

YUP! 1bar mate! :eek: From 2.5k, boost rises aggressively and you get shoved back pretty hard :cool: Pulls all the way to redline, so the power band is very fat. Pulls like a freight train from very low and it's totally transformed the drivability of the car.

I went with the 0.78 A/R, divided inlet T3 turbine housing, to suit the GSF headers. It has a 3" V-band discharge too.

If the GT35R can spool this quick on such a crude tune (I'm just using a generic Protomotive Stage3 CHIP), I'd be interested in knowing how the GT30R compares :eek: If you aren't after BIG HP numbers, but ultimate streetability & response, I'd say go for the GT30R ;)

I like my car like this though. It's a blast to drive and with the top down, the turbo sounds amazing when it spools.

juan ruiz 11-25-2006 05:43 AM

Merv ,how much power is the car making ?

Porschefile 11-26-2006 12:54 AM

I would also like to know how much power it's making. Wow, I didn't think a gt35r would be spooling that quick!

WydRyd 11-26-2006 01:09 PM

Haven't had the opportunity to dyno it yet. I've left the boost at 1.0bar for now, whilst I break things in, but I'm hoping to get it onto a dyno shoon to verify the A/F's and RWHP figures @ 1.25bar.

Mind you, I'm not really building a big HP dyno queen, but my goal of building a quick street turbo has been reached ;) I'm pretty happy with the end results.

My next phase will be to go complete stand-alone engine management for even better response and drivability.

I'll post dyno sheet as soon as I've had it done.

WydRyd 11-29-2006 06:10 PM

I was out tuning the EBC last night whilst it was a nice cool evening.

The B (or max) setting on the AVC-R has been set to nail the boost right @ 1.25bar. At this setting, it's insanely quick. The tach needle swings to redline THAT fast in all gears, it's very difficult to keep focused on the road and watch your RPM's at the same time. Once on boost, this turbo doesn't let up and it's quite a task to choose the right shift point before hitting the limiter. I have a whole new level of respect for you guys who drag race your cars with monstrous HP :eek:

I've set my boost levels accordingly:

LOW = 1.0bar
MED = 1.1bar
HIGH = 1.25bar (tyre shredding in 3rd gear :cool: )

Hopefully next week I can book in some dyno time to verify all my A/F's are in check, at each setting.

The GT2 EVO CAMs are also very aggressive and pins you back when they "kick in"... I'm in love again, with this car :D :cool:

RarlyL8 11-29-2006 07:12 PM

That's awsome!
A buddy has modded his turbo engine and is now complaining that the front end is too light in ALL the gears. Headlights in the sky.
Are you having that problem?
How can you keep the rear end from squatting too much and still have a good ride?

WydRyd 11-29-2006 07:28 PM


Originally posted by RarlyL8
Headlights in the sky.
LOL! Yes, I have the exact same problem... front end gets very light and it looks like your launching at a 30 degree angle.

Mind you, I'm still running OEM Carrera torsion bars (with KONI adjustables), which I think are too soft for the capabilities of this car. I need stiffer torsions, especially in the rear :(

Would love to do a rear coil-over conversion, but this is a street car, so I may just upgrade the torsions instead :confused:

RarlyL8 11-30-2006 09:17 AM

It is common for hi-po 930s to run 30mm bars out back. Mine are 28mm and they're not big enough for my mildly modded engine. My concern was ride comfort when I installed the 28s. I don't want to get into annual kidney transplants.
The next thing I am going to try are adjustable shocks. We'll see how that goes.

adomakin 11-30-2006 11:41 AM

nice one Merv! just one question-is 1.25 bar safe for these engines? im assuming that 1.25 is just for them short blats?

WydRyd 11-30-2006 01:14 PM


Originally posted by adomakin
nice one Merv! just one question-is 1.25 bar safe for these engines? im assuming that 1.25 is just for them short blats?
That's exactly what I'm going to ascertain when I get her on the dyno to verify my mixtures are in check at that boost level.

The high-po guys like Juan Ruiz and Mike Rombotis have been running those boost levels (or more) on pump grade 93 or 94 octane fuel without any dramas. That's on their EFI'd cars, like mine, and have countless drag race events under their belts :eek:

Mind you, I don't think it's wise to run that sort of boost on a track, but for pure street which only sees occassional full boost bursts, I don't think it's an issue. Again, the dyno will verify if all is OK.

For me, 1.1bar is plenty powerful. Might just bump it up to 1.25 when I demo the car for joy rides :D :cool:

Edit: Mike was able to run 1.55bar/22psi on pump grade 94 octane fuel in his TT Carrera. The result? 661crank HP & 675tq :eek: If he can run that kind of boost safely on pump fuel, I'm sure 17-18psi would be OK ;)

adomakin 12-01-2006 08:38 AM

thats what I like to hear Merv!

All times are GMT -8. The time now is 12:45 PM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2020, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2020 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website

DTO Garage Plus vBulletin Plugins by Drive Thru Online, Inc.