Considering going Turbo on my 3.8
 

I have been planning my build for a while now, I have a 95 993 motor and a new set of CWM 102 pistons and JE cylinders for a 3.8 11.5:1, rebuild high comp, I was considering going ITB's, megasquirt2, I'm going street/track, it is basically a hot rod project.

lately I have been contemplating going turbo to get more HP

I have a set of 1 3/4 even length SS 3 bolt headers and a plastic 993 intake manifold, I have a mate who has various turbo parts intercooler plumbing of a 3.6 turbo.

1. for a 3.8 what turbo should I purchase?
2. what cams should I run?
3. Do JE make a turbo piston in 102mm?
4. What about ITB's with a turbo any benefit?
5. should I go single or twin turbo?

Any advice apprciated

Matt

"Eye of the Toiger" - I love that, mate! ;)

Afraid I'm probably not the guy to ask - but I thought I'd be helpful and just give this thread a *bump* - hope that somebody else can contribute.

As with anything, depends what you're after. If you're after monstrous horsepower (800+FWHP), drop 'Juan Ruiz' or somebody a line...

If you're going to track the car, I'd have thought twin-turbo would be the choice. (But I don't know anything compared to these boys ;))

thanks TJ,

I really just need an idea of what turbo charger and cams would go nice with a 3.8 for street and track days, I don't want an on/off switch, but a nice balanced machine that I can unleash the mongrel when I want it, 450 hp would be nice

Jonathan ('JBL930') has stuck a 3.6 993tt engine into the back of his ~'84 930.

Was developing an estimated 520BHP at the crank when I saw it on the rollers, back in May a year or 2 back. Provided you can get the fuelling, one would have thought that - with an extra 200cc - you should be getting similar numbers.

He has a very long but very interesting thread you might want to take a look at:
http://forums.pelicanparts.com/911-930-turbo-super-charging-forum/506171-my-930-993tt-engine-project.html

Someone got around the 450 crank mark just adding boost to an N/A 993, standard compression, was document here or rennlist a while back. Dropping compression to 8.1 and running .8bar on a 3.2 gives your goal hp, with a 3.8...

You can use you headers with an M&K turbo pipe, they were designed for use with 993 HEs and should bolt up top your headers, twin wastegates, very slick.... You just want to keep our compression up and boost low to avoid the on off switch.

Your mate's 3.6 intercooler could work with a few mods, they're a prized intercooler around these parts...

Will be so much fun, you gotta do it!

Definately go with a M&K turbo y-pipe, very simple install and perfect fit! You will not be disappointed with the results.
GL!

Cool i will talk to Ben, any one know what turbo charger I should get.

I have read that for a single a K29 or a garrett GT35 any idea's?

Here's the car I was talking about earlier:

993 turbo project - 6speedonline.com Forums

Yes, J&E will make you turbo pistons. 8/1 compression w .8 bar is a good combination. If you have the stock 993 cams they are great. The plastic manifold can make up to 750 or more HP. Probably do not want to run a KKK or T3 hot housing turbo. Probably a T4 based GT35 for up to 600hp. .83 hot housing will spool up fast on an EFI turbo. Probably in the 2500rpm range on a 3.8. However, you could go bigger and badder but then you need rods...

Some of the magic is in the intercooler. Bell makes a good one.

As to exhaust, what do you really have? If something like B&B headers they are to long. You want short or short and equal headers. If you have the 993 heat exchangers the M&K Y pipe is the best shorty w heat system.

Or, check with RarlyL8/Brian about equal/equal length headers w a T4 flange. Tial makes a light weight SS hot housing GT turbo that uses a clamp to mount instead of bolts that could be cool.

If you come across a set of take off 993TT heat exchangers or headers, doing a twin turbo package is possible but the new single turbos are probably as efficient and except for the exhaust, easier to plumb.

If you have the stock 993 Motronics you might consider adapting it with a larger MAF sensor and custom chip as it would keep the knock sensing function.

That's my two cents worth.

cheers for that 911st, I may go for the B&B headers

I also have access to a Alloy manifold of a 964 which has had mods done to throttlebody & adapt an intercooler. Can that make the same HP as Plastic?

Matt

How much HP are you going for?

I am not a real expert.

I did read in Bruce Anderson's book that Protomotive used extrude honed alloy manifolds but if he needed more be went with the plastic one's and they were "12% more efficient" for what it is worth. He also shows a dyno sheet on a 3.8 TT he built that made 750hp.

If you manifold is set up for a 930 style intercooler it might be easier to go with the Blown Six C2 intercooler for a nice motor. Some have not been tottaly happy with there quality but the end tanks are a better design that most fabricated tanks.

There is a lot to making a big HP turbo that will live on the track. Keep it pulled back to a mild tune at say 500hp and you can have a lot of fun. Don't forget it takes a lot more cooling, clutch, brakes, transmission ....

A built NA 3.8 w sport cams, chip, headers in a light car could be a lot of fun and give even the largest turbos a fit on the track.

Me, I would love a set of PMO carbs on a 3.8 in a light car w great suspension.

Ditto on the t-4, t-3 is restrictive and on these cars you want to keep the heat out of the cylinders and a t-4 housing is good for that. On mitsu EVOs, some make up to 700 horse on a t-3, but at 40 psi! On our cars you don't want that much, so the t-4 would be a little better as it could be more efficient at lower boost. Being that it is 3.8, I would even consider a .96 hotside because you have displacement on your side and you wont be as sensitive to lag as our smaller displacement 3.3's.
A good guy to contact is Chris Carrol of TurboKraft as he has done many nutty 3.8 motors and is a dealer for AEM efi if interested.

my 2 pennies

Kris is right. You need to talk to someone who has actually done this mod as we are all just guessing about turbos until you provide air flow numbers. Who knows what the most efficient turbo will be for a 3.8L.

As for cams, you really need to start here first because it is the component that manages air flow through the motor. If it were mine, I would be looking at custom for my application. Performance Developments (a kiwi) makes a great GTII improved version that works through out the power band (2800 - 7000rpm).

Here is something to consider on the pistons - Mahle in the US is now more flexible in price and build, so look at them for a set of 102mm pistons - but wait. Consider a set of custom rods that are a bit longer (a mm or so) to stroke the motor - Mahle will off-set the piston pins on the custom pistons.

Now take the airflow that the new cams and stroker rods make, then pick your turbo. With the combination of longer stroke, the big vacuum pulled into the cylinders will give you good torque, but longer stroke also means compression is accelerated, so watch for detonation (it's a trade off). So your turbo will need to big, but very efficient at low boost levels and high air volumes. Most likely, you'll need a ball bearing turbo.

You have a great platform for a torquey turbo motor - don't stress over the HP numbers. While you're pulling away from the light, the guy next to you with 100 more ponies will still be waiting for the turbo to spool up.

Good luck

Dont use the je or CMW pistons cylinder set up . I did and it did not last. I use mahle pistons on my 3.8 and 3.6. My 3.6 made over 650 hp at 1 bar. at the wheels with small t3 turbos it has evo gt2 cams. pautter rods and ported heads.. I now use twin gt35r. turbos and they are fine. I would recommend 3071 or gt30s. I may be selling my 3.6 engine. i broke the engine in removed it because i wanted to use the 3.8 instead...

JE & CWM are meant to be excellent quality, why would they wear out? what boost/CR were u running?

A couple of years ago, JE went to a different forging process so maybe that's part of the problem. There are a lot of JE's out there in Porsche's with no problems, but if you're going to use OEM cylinders, why not stick with Mahle (still a premium to JE though). I have steel cylinders, so JE works just fine.

speed racr - what are you going to ask for your 3.6L?

T4 hybrid turbos, and MOTEC EMS with EFI, GT2 Evo cams are a good mild setup.

Here's what you need:
83 lb Siemans injectors
dual t3/t4 garrett ball bearing turbos:
50mm compressors
t3 stage 3 turbin wheels
.63 a/r exhaust housing
twin outlet intercooler
stainless equal-length exhaust headers with dual Tial race wastegates (0.6 bar springs)
dual-outlet custom stainless exhaust system
J&S knock retard unit
dual msd 7al digital ignition boxes with high performance coils
3.2 stock intake manifold with 80 mm throttle body.
lightweight flywheel


I still have my headers, intercooler, charge pipes, exhaust pipes and intake manifold/throttle body. Basically everything but turbos and wastegates from my old setup for sale to make plug and play pretty easy.

Let me know if you want it.

EDIT***** If you want to know what it takes to run a 3.8tt setup with ITBs and tuning PM me as i'm doing that right now - and it will empty your pocket book quicker than you can imagine. But it'll be worth the effort if you're looking for huge hp.

I would suggest 1.625" headers for your application for quicker boost response and larger power band through improved velocity. I'm starting a build for a rear mount twin turbo setup using my headers with short secondaries and K16 turbos. K16/24 hybrids are very popular with the 993tt guys.

Reaper930 sent u a PM

matt