Project Twin Turbo - Making Progress
 

Gentlemen, it's starting to really take shape. All of the "major" fabrication is done.

http://forums.pelicanparts.com/uploa...1060831529.jpg

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Nice work Mark. Is that a Spearco core? I see you made your own heater block off plates

Do you need an apprentice to polish your cam cover bolts? OK, I'll even scrub your floor with a toothbrush. Teach me, o' wise one. :)

How are you planning to drain the oil from the turbos?

Any guesses on the HP output? If the dyno reads less than 110 HP, I would consider your project a massive failure. ;)

jurgen

Dean, yes it's a Spearco. Spendy little bits they are. They are very proud of their stuff. Nice catch on the block off plates. I'll update my website with lots of pics sometime.

Jurgen, you are funny. I'm still debating on several potential solutions for the oil scavenging. The fail safe way is a single stage dry sump pump. The drawbacks to that are high cost and requires a 2 belt system because it has to turn at a reduces ratio compared to crank. I'm also considering a power steering pump but haven't concluded if its viable. The pros are lower cost and doesn't require reduced ratio so I could retain a single belt setup. The cons is its somewhat of an unlnown and I'm a little shy of trying new things for something so important. I've been doing R&D for 3 years now and want to stay "this side" of the line. If it only makes 110 hp I will consider it a failure too.

Very nice.

As far as turbo scavenging goes, why not just run a 930 style turbo scavenge pump off of one of the cams?

because it's questionable if a regular 930 pump can support twin turbos. I know I can go with an aftermarket pump (for back of cam) but they cost as much as a professional dry sump pump and they are really just a modified VW oil pump.

beautiful work!!!

Hey Mark

Do you have a good source for the Spearco's? The are the best core around but I can only buy them from a middle man and he wants a huge cut.

If I were you I would adapt a VW pump for the scavanging unit. It looks like you have the skill to do that:)

Again nice work;)

Nice intercooler.
Good job.
I'm working on a similar project here.
Which turbos do you use ? K26 ? Do you keep them with stock trims and A/R ? Are the two ones identical ?
What kind of throttle do you use, it looks to be the 3L2 plenum ?
How will you manage the engine ?

Sorry for the questions, I'm so excited to see such another work :P

Congratulations ;)

Best regards
Luc.

Why not use a 935 oil pump, wouldn't that supply it fine?

Mark,
Beautiful work. What's the base platform? 3.2?

Impressive work! Are you using the same base engine as The Beast, or is this a new engine? What happened to the beautiful supercharged engine?

Blown, email me directly with the Spearco stock number and I'll see what I can do.

961, they are K16's that will be modified by Kevin at Alimo. I'm using a Haltech E6K for engine management.

All, sounds like you haven't been to my webiste. It has full details on the motor being built. It's not updated for the turbo stuff yet, it still has the SC stuff on it but you will see.

Looks beautfiul ... hope it goes as fast as it looks :)

On the other side of things, I am really interested to find out how your headers work out. I remember you mentioning that they don't need to be equal length runners, but I'm not so sure. I'm not saying your wrong ... I hope that I am. Are you going to dyno the motor once complete? Or are you gonna just stuff it in the car and go for broke?

I would really like a link to your site to get specifics on the engine's guts, if you would be so kind as to provide one.

It's a great looking motor ... but those turbos are awfully close to the valve covers. Is heat going to be an issue?

Also, what car is this monster going to motivate? Would be a blast in a 914-6 :D

I think in turbocharged engines, short exhaust headers to the turbo are more priority for lag reasons than equal length. I believe equal length is a big deal for really high rpm, high horsepower. Basically the shorter the exhaust manifold, the less volume to fill with exhaust pressure to spool the turbo up.

The link to his site is in his Signature line....titled "The Beast"

Just breathtaking

Turbo headers just need to be short and free-flowing. Usual N/A wisdom is not a big player here.

Turbo lives on flow and flow is proportional to volume, volume is proportional to temperature (PV = nRT). Long headers just cool down exhaust gases, so there is not much left to turn the wheel. That's what they mean when they say that turbo uses wasted thermal energy and the reason why people use thermal-wrap around their turbo-headers. You want turbo as close to head as possible in order to use as much wasted heat (=flow) from the exhaust gases as possible.

Doing equal-length headers thing will marginally improve scavenging in turbo car (beacuse there is lot's of backpressure = impeller) and those long pipes will just cool down gases and weight a lot, so it's not a good option on turbocharged cars unless they can be made really short.

You are one of the ulitmate conversionist on this board. First the Super Charger, now this. Looks awesome.

Thanks everyone. Yes, my website is on my signature but just in case its: www.mark.hargett.com

I wasn't entirely please with the air filter boxes so I changed them today. Now it looks like this:

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http://forums.pelicanparts.com/uploa...1060895430.jpg

Very, very nice. Did you ever get the sequential shifter worked out?

Never did finish it. I always had so many issues to work on with the SC setup I never had time. Then I decided to go twin turbo and I still don't have any time. When I get it back on the road I won't have any more money! I'm ready for a break too, I've been working on this project for over 4 years I think. I might still do it some day. I still beleive in the idea and think it would work pretty cool.

Unbelievable process. Thank you for the website. I walked through the whole process in less than a minute.

Looks great Mark!

I've been away for a while and didn't even know you had actually started this project. I really like the air filters. A great detail usually forgotten in turbo cars is access to ambient temperature air.
Didn't see the wastegates. Did I miss them?

Hey Rarly dude, glad to see you around. I pretty much ghost mostly. They are K16's which have internal wastegates. I'm going to send them to Kevin at Alimo for some special treatment. How's your car running?

checked the site. two words: absolutely amazing

Simply said...BAD!! F#$%ing BAD! Killer man....im totaly impressed.

I realize this is likely to be a fair weather flyer but what are you going to do about the air intakes when you get caught in the rain?

drain holes at the bottom :D

Thanks everyone.

Yes, a fair weather Beast it is but just in case.... I was planning on making some trick covers that just clip onto the top of the air filters in case of rain. They would still be able to breath from the side. Dunno for sure, as Ronin indicated drain holes if nothing else.

The car is running great Mark. I drove it 500 miles from IL to AL a few months ago with not a hitch, glitch, or hickup. I couldn't be more pleased - but it's a dam*ed good thing given the cost and headache I went through. We went for a mountain blast this AM. Had a very cool 5 mile race with a new M3 on some very twisty roads. Makes it all seem worth the effort.

I read back some time ago in one of the Porsche mags about a turbocharger that used sealed bearings requiring no external oil flow. This would be a GREAT thing for aftermarket 911 turbos. I've got to revisit that article. You know about these?

das would be the Aerocharger VATN turbocharger. It has a self-contained oil charge. The two drawbacks are cost and size. You would need twin Aerochargers for most 911 applications. As I recall, it is one of the most efficient turbochargers on the market.

Definitely trick!!!

Jurgen

Definitely trick, but they are also prone to failure...

As far as I know, they're not generally available any more. You might be lucky enough to have them serviced, but that's about it.

A self contained oil supply doesn't sound like the "hot" tip, especially since it's not easy to water cool the center section on a 911...

Definitely a cool project. It's a shame it took the factory so long to ditch the big singles and CIS. Saab in the '70s was more advanced than some of the turbos Porsche sold in the 90's (!).

Matt
'73 911E

Wow, that is one of the nicest motors I have seen. Congrats.

I just finished reading about the vatn aerocharger, anyone know of a website that lists they're availability?

I have a question here. I have yet to own a Turbo flat 6 but have had several other turbo cars so I have thought about this a bit. The oil scavange from the turbo(s) on other cars is no problem due to the position of the turbo(s) letting gravity do the work, but on a motor where the turbo is lower then the sump I can see the issue. Here's my question: If the oil is fed to the turbo by the main oil pump, why not just route the drain line back into the system higher up and let the feed pressure push the oil out? As long as there is no obstruction the oil would have to leave the turbo would it not??

Just wondering...

Alex

If there's any restriction in the drain line, the oil will build up around the seals and enter the compressor and/or turbine, creating a big mess.

Turbo seals and center sections are not designed to be filled with oil.

They must properly drain or the shaft will have to deal with unneccesary drag and its seals will be saturated and leak. For this reason the turbo oil drain usually also needs to act as a vent.

For this reason you must run the drain to a vented pick up point that is lower than the turbo.