GT35R turbo for 3.4L?

[911TT33]

0.96 is too big for our motors. No wonder its laggy as hell

Drop down to a 0.82 ball bearing unit and you'll see/feel the difference immediately... Guaranteed!

The GT35R comes standard with the 4" inlet 2.5" outlet compressor housing too, so your existing intake plumbing should mate up without any major mods. You can of course order them with a 3" inlet, 2" outlet too.

I'd be interested to know the diameter of the primaries on your custom headers. Too big, and that also affects spool

Btw, can you actually get a 0.9 bar spring for the OEM waste gates?

[spuggy]

Originally Posted by RarlyL8

The K27 hybrids and high flows will easily support 400WHP and drop your boost 1000+rpm. They also bolt on and use the OEM oiling system.

What Brian says.

I would like an honest 400 RWH (.9 bar max) with better response off the line and some decent legs at the top.

I'm running a K27/HF with a Kokelyn/GHL's, and I make 370RWHP on CIS with the stock wastegate/spring. 6PSI boost @ 2400 RPM in 3rd, all in by at least 3000. It doesn't run out of boost at high RPM - just fuel.

With MOTEC, 3.2 intake and port-matched heads, you should be closer to 500RWHP than 400RWHP.

[forte500]

Okay, I am sold on the GT35, plus it won't require major changes or fabrication...I will measure the primary diameter......do you recommend the twin scroll/ports on the turbine? I could easily have a seperator welded on the flange as well if that helps.


RE: .9bar spring for OEM wastegate...tuner says he can get/make one and feels no need to swap out (i.e. TIAL, etc.).

[JBurer]

I think that's a good call, given the current setup.

Pretty sure my GT35R is not a twin scroll. I believe that requires a divided manifold to work properly (?)

On boost control and wastegate springs - have you considered using the MoTeC to control boost and just leaving the 8psi spring in place?

Originally Posted by forte500

Okay, I am sold on the GT35, plus it won't require major changes or fabrication...I will measure the primary diameter......do you recommend the twin scroll/ports on the turbine? I could easily have a seperator welded on the flange as well if that helps.


RE: .9bar spring for OEM wastegate...tuner says he can get/make one and feels no need to swap out (i.e. TIAL, etc.).

[911TT33]

If the merge collector on your headers is not divided, then there's no point going with a divided inlet turbine housing. Just go with an open inlet turbine housing.

Here's an example of a divided 930 manifold suitable for a divided inlet turbine housing. The idea is to isolate exhaust gas pulses from the left and right side of the motor all the way to the turbine wheel to maintain exhaust energy and maximize turbo response.

http://goingsuperfast.com/images/Porsche_930_header_NEW-5.JPG

No affiliation... Just showing an example

[forte500]

The primaries are 1.5" I.D. and secondaries approx 2" I.D....what were yours with the GT35 setup?

[911TT33]

Originally Posted by forte500

The primaries are 1.5" I.D. and secondaries approx 2" I.D....what were yours with the GT35 setup?

Yep, the same. Got any pics of the intercooler?

[forte500]

Did you get good boost in 1st? (i.e. able to spin wheels)

[JBurer]

Frank,
Off topic, but mind if I ask what lift that is you have?
How tall are the ceilings?

Originally Posted by forte500

Did you get good boost in 1st? (i.e. able to spin wheels)

[Tippy]

Originally Posted by forte500

do you recommend the twin scroll/ports on the turbine? I could easily have a seperator welded on the flange as well if that helps.

Although I've yet to see a 911/930 run a divided/twin scroll and the results, it has to help. So, yes!

Originally Posted by 911TT33

If the merge collector on your headers is not divided, then there's no point going with a divided inlet turbine housing.

Here's an example of a divided 930 manifold suitable for a divided inlet turbine housing.

http://goingsuperfast.com/images/Porsche_930_header_NEW-5.JPG

First, it is very easy to add a divider - I did on mine. So, I'd would buy the twin scroll housing and add the divider.

Second, that picture is NOT a divided flange. It is too thin-walled to survive the heat/stress. It is simply where the two secondary tubes were mated. Also, the supposed divider (which it is not) doesn't meet up flush with the flange. The energy would simply bypass back and forth and make probably next to no benefit.

Not trying to be pompous, just do not want people buying headers like that, putting on a twin-scroll turbo, and getting 0 benefit!

[911TT33]

Interesting, that's the first kokeln IC I've seen used on a 3.2 intake manifold. Usually people go with a full length IC and relocate the AC condenser.

Btw, gorgeous looking car! You will be wrapped with the new performance of the GT turbo... It will feel like a different animal

Those headers look like Marco Menzies equal length headers!? You car was obviously built with big top end HP in mind.

[forte500]

Thanks for everyone's input....I ordered my GT35. This is great resource..intend to give back as I learn more about these cars and their limits.

[JBurer]

Frank - any details on the lift to share?

[forte500]

Sure thing - I bought the lift in order to keep 3 cars in a 2 car garage. Fortunately, I have high ceilings 11ft (minimum required). I paid approx $1800 for the lift w/ramps and drip pans. Most important is a locking feature (ladder design) that is internal vs. a welded tab on the outside of the lift posts. There is no way for the lift to come down accidently! The standard lift (what I have) allows for a reg car/sedan up to 59" high and a sports car (less than 55" high) to fit under an 11ft garage. If your garage is higher, you may want to get the extended lift, which allows an SUV to fit under.

The lift came in several sections (heavy) but I was able to get most into place with a hand truck and then get a friend to help position the final track. It was pretty intuitive and a good thing, as the instructions were in Chinese and very poor diagrams It was delivered by a large box truck and typically requires a lift to transport from the truck to a residential garage. I paid the truck driver $100 and he agreed to help me move it in. Be sure to ask this when you buy it as some vendors will require you to have loading dock or lift.

It took about 3hrs to assemble and was very straightforward. It came with dollies to move the lift around and cement bolts to adhere to the garage floor. I chose not to drill-up my floor in case I decided to relocate the lift in the future. I did relocate the hydraulic motor at another corner so it wouldn't be in the walk-path in the garage. At first I tried it without a car on it - it felt flimsy and would rock considerably back n' forth …..with weight on it, it was rock-solid even w/o the bases bolted down. To be extra safe - I attached one side to the wall joists and now the lift doesn't rock even when the car is off.

I have to say...I love the set-up and it makes repairs a snap. Send me a PM if you want more details or know where I bought it.

FF

[911TT33]

Originally Posted by forte500

Thanks for everyone's input....I ordered my GT35. This is great resource..intend to give back as I learn more about these cars and their limits.

Nice, now make sure you give us all feedback on the end results

Do you have an intercooler temp gauge for your intake? It would be interesting to see how efficient that kokeln unit is. You can buy them from Davtron I think. They measure pre and post IC temps.

[fredmeister]

Originally Posted by forte500

Thanks for everyone's input....I ordered my GT35. This is great resource..intend to give back as I learn more about these cars and their limits.

Sorry to hijack the thread but what rims do you have on that car? They are nice.

Fred

[JBurer]

Measured last night and my garage ceilings are only 9.25 feet. Time to move

Originally Posted by forte500

Sure thing - I bought the lift in order to keep 3 cars in a 2 car garage. Fortunately, I have high ceilings 11ft (minimum required). I paid approx $1800 for the lift w/ramps and drip pans. Most important is a locking feature (ladder design) that is internal vs. a welded tab on the outside of the lift posts. There is no way for the lift to come down accidently! The standard lift (what I have) allows for a reg car/sedan up to 59" high and a sports car (less than 55" high) to fit under an 11ft garage. If your garage is higher, you may want to get the extended lift, which allows an SUV to fit under.

The lift came in several sections (heavy) but I was able to get most into place with a hand truck and then get a friend to help position the final track. It was pretty intuitive and a good thing, as the instructions were in Chinese and very poor diagrams It was delivered by a large box truck and typically requires a lift to transport from the truck to a residential garage. I paid the truck driver $100 and he agreed to help me move it in. Be sure to ask this when you buy it as some vendors will require you to have loading dock or lift.

It took about 3hrs to assemble and was very straightforward. It came with dollies to move the lift around and cement bolts to adhere to the garage floor. I chose not to drill-up my floor in case I decided to relocate the lift in the future. I did relocate the hydraulic motor at another corner so it wouldn't be in the walk-path in the garage. At first I tried it without a car on it - it felt flimsy and would rock considerably back n' forth …..with weight on it, it was rock-solid even w/o the bases bolted down. To be extra safe - I attached one side to the wall joists and now the lift doesn't rock even when the car is off.

I have to say...I love the set-up and it makes repairs a snap. Send me a PM if you want more details or know where I bought it.

FF

[DonE]

Originally Posted by vas930

Does anyone have any documented evidence that the GT spools faster than the K27?
I always read that some people feel it does.
Then I see Brian say he has not seen this to be the case.
I listen to what all you guys say. I have great respect for Brians knowledge.
Surely after all this time someone has done a documented test.

All my documentation went when I sold my car. Since it's EFI, you can get the GT to spool faster from idle (I proved it) but where the GT shines is in throttle response. The K27 center sections (bushings) can't spool up as fast as ball bearings and the vane technology that's on the GT. This is assuming you've tuned the motor well but to be fair, if you're looking for a dramatic difference, there isn't one. You get it down low quicker and in quick changes to throttle position.

I thought it was cool when I shut my motor off (it had a GT35R), the turbo would continue to spin for something like 45 seconds. The K27 stopped in 10 - 15 seconds from idle.

The ball-bearing vs. bushing turbo discussion is ALMOST as bad as one on which oil is better.

[forte500]

John, sorry to hear your ceilings are too low for the lift

Fredmeister - the rims are Kinesis K28 (w/ flat lips vs. the stepped). Fronts are 18 X 40 X 245, rear are 18 X 30 X 315. I would have never thought gold would look so nice, but as my wife says " they make the car". They really do in my opinion and resemble racing'/cup car wheels. Thanks...

[Hukdunfoniks]

I ran the GT35 on my 3.3L and now the 3.4L...shes a beast! Youll love it! I understand the twin scroll will give even better numbers. Enjoy