Garrett GT42R?

[aspemo]

I'm thinking of replacing my Schwitzer SG300 with a ball bearing turbo. Garrett GT42R, GT4088R or GT4094R.

My goal is 700 Hp with resonably good low and middle rpm performance.

How to deal with the cooling, do you think it's possibly to leave the water cooling lines plugged or use them with oil?

What would you recommend for turbo? And how would you make it as loong living as possible?

Appreciate your inputs.

[tarheelturbo]

i'm just going to go ahead and say it before someone else does.
what are the specs on your motor? EFI i assume?? the more details the better everyone will be to help you!

[beepbeep]

There is nothing called "good low RPM performance" with 700hp from 3.3L and single turbo Do not plug oil into water channels, you'll just cause oil pressure drop for the engine. Either fabricate water coolant loop or leave them open.

I believe GT40R is more prudent choice even if it might not fully support 700hp.

[aspemo]

Originally Posted by tarheelturbo

i'm just going to go ahead and say it before someone else does.
what are the specs on your motor? EFI i assume?? the more details the better everyone will be to help you!

You can se some of my mods here :

some pictures of my new manifolds and IC

Following things is done:

Totally rebuild engine, new bearings etc, crank gasflowed, Pauter rods, ARP rod bolts, GT2 topbolts, Nirister rings, ported top 41 mm intake ports 38 mm exhaust ports. Ti retainers, race springs, modifyed 993 cup rockers, GT2 evo cams, Carerra 3,6 intake manifold, 50 mm Tial dump valv, twin 38 mm Tial WG, custom made equal length primary pipes 44 mm and secundary pipes 54 mm, custom made full bay IC, LINK EFI, twin AN8 fuel lines, one AN8 return line, Russ Collins 1000 cc injectors, twin 040 Borsch fuelpumps to a catch tank , and twin 044 pressure pumps, monitoring EGT, lambda, broadband lamda, fuel pressure.

New starter and dynamo, new constraction for fan drive, better durability and higher air volume, to increase cooling. A big oil cooler in the front. 100 L racetank.

Totally rebuild chassie, adjustable swaybars front and rear , Bilstein RSR suspension, 31 mm torisonbar rear with 200lbs coilover springs, steel monoballs, camberplates, polygrafite bushings.

Totally rebuilt gearbox, regeared 3d and 4th gir by lowering 15%, LSD.
Escavator driveshafts, 128 mm CV joints.

Hargettshifter( pure **** construction)

Rollercage, race seats, race harness. Improved aerodynamics, steel plate under the car, 964 body, rebuilt 3,8 rear wing, front splitter.

I have for sure forgotted somethings.

I hope this will give you info to give me some advises.

[aspemo]

Originally Posted by beepbeep

There is nothing called "good low RPM performance" with 700hp from 3.3L and single turbo Do not plug oil into water channels, you'll just cause oil pressure drop for the engine. Either fabricate water coolant loop or leave them open.

I believe GT40R is more prudent choice even if it might not fully support 700hp.

What do you think I will gain in drivabillity and power by using a GT40R instead of what I have at the moment a Schwitzer 300SG, it gives full boost at 3500 rpms.

[kenikh]

Originally Posted by beepbeep

Either fabricate water coolant loop or leave them open.

Would love to see a pic or diagram of one of these if anyone has built one!

[Speedy Squirrel]

I would say you will have to wave bye bye to "good" low end response with a single turbo at a true 700 flywheel HP (not to be confused with 700 SoCal chassis dyno HP)

What is the diameter of the S300 at the turbine exducer (the biggest diameter, you have to take the housing off to measure it)? I recall they were 86mm. The GT42 is 82mm, and has ball bearings, so you have at least that going for you.

The GT40 is out for you. For 700HP you will need the GT42. The GT4202R - 774595-5 looks right by my calculations:


I think you will get roughly the same numbers from the Garrett site. That's almost 40 psi boost there cowboy, and with a non-turbo engine case and Pauter rods I would be afraid, VERY afraid.

[TurboKraft]

The GT40R is a really good turbo and works well on an EFI 930. You can have 1.0bar boost by 3,350rpm, even a 3.3L with just 7.0:1 compression and so-so engine work.

Here's an example:

Well known 930 racecar running very competitively in POC and PRC (consistent high finisher) was brought to our shop. Pretty tired machine, running 2 seasons on the same engine, and not the greatest engine preparation (cooling tins missing, rock hard hoses, oil drips everywhere...)
- original 3.3L P&Cs, <7.0:1 due to deeper valve pockets, twin-plugged heads
- heads "ported" (roughly opened) to 41mm/41mm
- GT2 cams
- GT40R with 1.06A/R turbine
- modified B&B headers, converted to T04 flange
- dump pipe
- Tial 46mm WG
- full width intercooler, albeit with poor inlet pipe configuration
- Carrera intake manifold & throttle body
- older Autronic engine management, twin MSD CDIs with 964 distributor -- kaput integrated boost solenoid control channel

We built new custom twin scroll headers with twin wastegates, a 3" race muffler to meet sound requirements, and re-plumbed the charge pipe between the turbo and intercooler.
(Tried to fix as many other wrong things with the engine as we went along, but there were absurd budget constraints -- can't make chicken soup from chicken s....)

Baseline dyno in green.
485.3rwhp @ 5,772rpm, 19.3psi
458.0tq @ 5,256rpm, 18.6psi
bad boost creep to 19.5psi @ 5,794rpm -- inefficient exhaust design, too small WG
109-octane

Dyno after in red.
515.0hp @ 5,915rpm - 16.8psi
528.8tq @ 3,717rpm - 18.0psi
peak 19.6psi @ 3,605rpm
109-octane
Boost fluctuating some with a double-adjustable manual boost controller not perfectly dialed in, but at least not more runaway boost creep. Off the dyno and straight to the track.




Use a conservative drivetrain loss of 15% for the 930 4-speed, and that's about 622hp at the flywheel at 18psi. Not bad for a GT4088R 1.06A/R on a tired, low compression, beater 930 racecar.
I'd reasonably expect another 30hp on a better built engine with a newer, more sophisticated engine management system with integrated boost management -- and do that on 91-octane.

If you're shooting for 700hp and don't want to run race gas and really high boost, consider the GT4094R.

The GT42R will do the job, but don't expect it to spool up as quickly on your 3.3L. It would be a good fit if you had a 3.4L with Nickies, or a stroker 3.45L (76.4 crank x 98 P&Cs).
The 3.8L we're building now is getting something much larger than that, and still boosts like this GT40R on a 3.3L...

[aspemo]

Originally Posted by TurboKraft

The GT40R is a really good turbo and works well on an EFI 930. You can have 1.0bar boost by 3,350rpm, even a 3.3L with just 7.0:1 compression and so-so engine work.

Here's an example:

Well known 930 racecar running very competitively in POC and PRC (consistent high finisher) was brought to our shop. Pretty tired machine, running 2 seasons on the same engine, and not the greatest engine preparation (cooling tins missing, rock hard hoses, oil drips everywhere...)
- original 3.3L P&Cs, <7.0:1 due to deeper valve pockets, twin-plugged heads
- heads "ported" (roughly opened) to 41mm/41mm
- GT2 cams
- GT40R with 1.06A/R turbine
- modified B&B headers, converted to T04 flange
- dump pipe
- Tial 46mm WG
- full width intercooler, albeit with poor inlet pipe configuration
- Carrera intake manifold & throttle body
- older Autronic engine management, twin MSD CDIs with 964 distributor -- kaput integrated boost solenoid control channel

We built new custom twin scroll headers with twin wastegates, a 3" race muffler to meet sound requirements, and re-plumbed the charge pipe between the turbo and intercooler.
(Tried to fix as many other wrong things with the engine as we went along, but there were absurd budget constraints -- can't make chicken soup from chicken s....)

Baseline dyno in green.
485.3rwhp @ 5,772rpm, 19.3psi
458.0tq @ 5,256rpm, 18.6psi
bad boost creep to 19.5psi @ 5,794rpm -- inefficient exhaust design, too small WG
109-octane

Dyno after in red.
515.0hp @ 5,915rpm - 16.8psi
528.8tq @ 3,717rpm - 18.0psi
peak 19.6psi @ 3,605rpm
109-octane
Boost fluctuating some with a double-adjustable manual boost controller not perfectly dialed in, but at least not more runaway boost creep. Off the dyno and straight to the track.




Use a conservative drivetrain loss of 15% for the 930 4-speed, and that's about 622hp at the flywheel at 18psi. Not bad for a GT4088R 1.06A/R on a tired, low compression, beater 930 racecar.
I'd reasonably expect another 30hp on a better built engine with a newer, more sophisticated engine management system with integrated boost management -- and do that on 91-octane.

If you're shooting for 700hp and don't want to run race gas and really high boost, consider the GT4094R.

The GT42R will do the job, but don't expect it to spool up as quickly on your 3.3L. It would be a good fit if you had a 3.4L with Nickies, or a stroker 3.45L (76.4 crank x 98 P&Cs).
The 3.8L we're building now is getting something much larger than that, and still boosts like this GT40R on a 3.3L...

With my Schwitzer SG300 I have 520 WHP at 1.2 bar pressure. Seems to me pretty similar with the car that you describes.

I will consider a GT4094R and also check with a company that sells specially designed turbos, to design something that will hopefully give me a compromise.

Have you any experiences with the Australian Bilett turbo?

[TurboKraft]

I haven't used many Switzers or Holsets lately, but have heard the Switzers have make big advances. My tuning partner does a lot of imports, and that's the hot brand-du-jour these days. "Extended tip compressor wheels", aka undercut compressors -- reduced mass = less iniertia = faster spool.

That poor racecar had so much potential, just no more money to sort out its myriad BS. It should have been about 540-550rwhp. Again, I offer that as an example of a GT40R working well, in this case in spite of the rest of the engine...


Which billet turbo company in AU? I know of 2 companies in AU offering "billet" turbos.
According to Garrett, the main reason for the billet is they can quickly make a new wheel, be it a one-off or a small production run, for a fraction of the cost of casting. No measured performance gain on their test bench between two identical turbos, one cast and one billet.
Turbonetics markets it as a performance advantage, but I don't know anyone who can verify they have proven it as such.

[JBL930]

I have a friend running one of those GT4088r's on a very well built 3.4ltr engine, this engine was built buy the most respected man here in the UK and there was not a penny spared "everything" was done and more! And then tuned on the engine dyno by JUDD, running Motec etc etc. It made a little over 600bhp at the crank at 1.2bar. That is true, proper, genuine engine dyno power!

Quick list of what was done

GT4088R turbo
Custom intake, intercooler and exhaust.
Motec M600 with data logging, boost control, twin lambda, 6 egts
Twin plug heads
935 pistons
carrillos
cams
heads ported and flame ringed
shuffle pined case and ported
ported heads
twin plate carbon clutch
gt3rs oil pump.
High flow secondary fuel pump.

[Speedy Squirrel]

Originally Posted by JBL930

I have a friend running one of those GT4088r's on a very well built 3.4ltr engine, this engine was built buy the most respected man here in the UK and there was not a penny spared "everything" was done and more! And then tuned on the engine dyno by JUDD, running Motec etc etc. It made a little over 600bhp at the crank at 1.2bar. That is true, proper, genuine engine dyno power!

Quick list of what was done

GT4088R turbo
Custom intake, intercooler and exhaust.
Motec M600 with data logging, boost control, twin lambda, 6 egts
Twin plug heads
935 pistons
carrillos
cams
heads ported and flame ringed
shuffle pined case and ported
ported heads
twin plate carbon clutch
gt3rs oil pump.
High flow secondary fuel pump.

That sounds about right with a good engine management system. I would buy 600HP with that much boost.

I agree that the GT40 is perfect for 550 to 600 HP too:




But you hijacked this thread! We were talking 700 HP! That takes at GT42 and well over 2 bar, if everything else could handle it.

[Speedy Squirrel]

Originally Posted by TurboKraft

I haven't used many Switzers or Holsets lately, but have heard the Switzers have make big advances.

I don't think Schwitzer is advancing too much. They were bought out by BorgWarner and closed over 5 years ago.

I would say your SoCal correction factor is a bit much, but then you are selling HP and have to do what you have to do. I would say around 530HP with 18 PSI, perfect GT40 territory, and jives with what we have seen here in MoTown on our engine dyno with a similar setup.

[TurboKraft]

I would say your SoCal correction factor is a bit much

Have you tested a 930 engine on a reliable engine dyno, and then installed it into a standard 4-speed chassis and re-tested it on a repeatable chassis dyno?

[GT2EvoGuy]

I have direct experience with the GT4094R and it will definitely hit 700hp+ with a well built 3.3 turbo engine. Please read the thread that I posted a while back on the GT4094R. My motor made 585whp at 1.2bar using motec EFI and a 3.6 plastic manifold. I have GT2 cams which are not that aggressive. The biggest reason my motor didnt make more power is my heads, which have been ported, but were not ported very well. My shop (Auto Associates) tells me that better port work and more aggressive cams would definitely push me to 625-650whp. Their own 935 race car replica makes over 700whp at 1.2bar out of a 3.3 with 98mm P&Cs, throttle bodies and a GT42R so they have the experience to make that call. The GT42R is pretty tough to fit under a street bodied 930 due to its size (plumbing would be pretty hard) and its just strictly a top end turbo. The 4094R gives me decent response with the BB option and flows a good deal more than a 4088R.

[aspemo]

Originally Posted by GT2EvoGuy

I have direct experience with the GT4094R and it will definitely hit 700hp+ with a well built 3.3 turbo engine. Please read the thread that I posted a while back on the GT4094R. My motor made 585whp at 1.2bar using motec EFI and a 3.6 plastic manifold. I have GT2 cams which are not that aggressive. The biggest reason my motor didnt make more power is my heads, which have been ported, but were not ported very well. My shop (Auto Associates) tells me that better port work and more aggressive cams would definitely push me to 625-650whp. Their own 935 race car replica makes over 700whp at 1.2bar out of a 3.3 with 98mm P&Cs, throttle bodies and a GT42R so they have the experience to make that call. The GT42R is pretty tough to fit under a street bodied 930 due to its size (plumbing would be pretty hard) and its just strictly a top end turbo. The 4094R gives me decent response with the BB option and flows a good deal more than a 4088R.

How big are your ports? Seams to be a nice car you have. I will look in to the Gt4094R.

[GT2EvoGuy]

I believe the intake ports were enlarged to 40mm and Im not quite sure on the exhaust side. The port job on my current heads was nothing special so Im planning on getting a set of virgin 930 heads and having a top notch job done by another shop such as Xtreme. Im positive that better headwork and some custom cams would not only produce better top end horsepower but also result in faster spoolup. 700hp is a very very serious 930 motor but definitely acheivable on race gas. Individual throttle bodies would also help on the top end as the 3.6 manifold isnt designed for top end power.

[GT2EvoGuy]

Also, your motor has stock 3.3 P&Cs? Im thinking about also having my stock 3.3 cylinders bored out to 98mm and getting a set of lightweight forged pistons in 7.5 or 8.0 compression. That, along with the 3.6 crank I already have should help spool things up a little better, and I really dont intend to run more than 1.2 or 1.3 bar anyway. Might pick up 10-20hp with a bit more displacement and better piston dome shape. Every little bit helps