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Mon May 26, 2008 7:05 am

hi all.

first post here so please be nice...

I'm nearing the time on my diy project to address the engine and power...

I have a fair idea what i'm try to do but need a little help and advice to make it happen...

so far i plan to run 2 x twin empi 44 carbs... and twin turbos.... (not seen it done before)

i can't seem to find anyone online etiher with this set up

so first of all if you have any resource or link please post/reply...

heres is my concerns are will the engine product enough exhust gas to spin the turbos correctly....?

I pan to run either turbo in its own cylinder head side of engine, with each carb feeding the turbo..
this seems the easist soultion if i want to keep twin carbs...

the engine will run around 1.8-2.0L,

I have already puchased in the deal of the century 2 turbos however (now come the major issue these are off a toyota hiera 2.4L diesel didn't relaise at the tim of buying)

after some more reading online i understand a change to the carbon seal from the standard piston set up should get round the draw though/blow though issues...

but afer further invesitagtion i now fear these cant be used anyway as orginaly for deisel fitment and something to do with the seals failing....
as in disel engine fitment the fuel doesnt mix before the turbo and therefore the seals arn't designed to protect against degrade.

i also found a lot of advice saying deisel turbos ant good for petrol engine as they boost at lower rev's, but being it a aircooled engine surely thats a benefit to us?

the turbos are ihi h12 (vb15 code) both run normally 7 psi boost (more than enough for me....

and finally any good site for buying custom exhust bits to chop up?

thanks all.

Mon May 26, 2008 8:35 am

I think there's a forum for performance engines, found here:
http://www.thesamba.com/vw/forum/viewforum.php?f=12
Maybe have a talk with those guys...

Mon May 26, 2008 8:44 am

In America, we call that a grenade. :wink:

Mon May 26, 2008 9:19 am

hi there im running same sept im single turbo just need to build it :)

Mon May 26, 2008 9:20 am

Turbo engines are the one that really need to run right, if you think you give yourself a deal saving money using thrown together at the factory empi hpmx carbs, then your in for a headache down the line, get some decent carbs, dellortos or webers.

you may also notice non of the top turbo engine builders built twin carb twin turbos. :?

Mon May 26, 2008 10:25 am

Also, turbochargers set up for diesel applications generally have a wider pitch on the turbine blades to get it to spool at a lower RPM. Speaking in terms of VW applications (all that I'm familiar with) Diesel turbos are only designed to be run up to 4k engine RPMs.

Turbocharging a daily driven bus is bad news in my book, but there's going to be people that will tell you it can be done. Your biggest drawback is the lack of the ability to dissipate excess heat created by the turbocharger, not only in the increase in oil temp, but the intake charge (compressed air) will be pre-heated causing your engine to run hotter than normal. There are ways to combat this (intercoolers, thermal coated engine components) but you start talking BIG $$$. It's also worth noting that you can build a reliable naturally aspirated engine to go faster than is safe to drive the bus.

Talk to people that know, and have done turbocharged applications. Listen to what they tell you.

Krusher's advice of running a single turbo through a set of Legit webers or Dellortos is highly advisable. If money is no object (which should be the case if you're seriously considering a twin turbo project) Look into fuel injection as it responds better and is easier to tune with a turbo application.

I don't know anyone in the VW scene that is successfully running a twin-turbo system. There's got to be a reason.

Mon May 26, 2008 10:52 am

big bus mike wrote: I don't know anyone in the VW scene that is successfully running a twin-turbo system. There's got to be a reason.

Not saying I don't agree with you on what you said, but there was a '59 beetle vert at Bug Jam last year that had a twin turbo type IV in it.

Mon May 26, 2008 11:00 am

It just goes to show there are people with more money than sense...

Mon May 26, 2008 1:22 pm

big bus mike wrote: It just goes to show there are people with more money than sense...

Actually, they only thing they had money in was the parts, if I remember correctly. It was a father son deal and they did the whole engine setup themselves. Custom made the manifolds, even. It was very, very cool. I spent a good bit of time looking at it. I was impressed.

Mon May 26, 2008 5:39 pm

Andrew wrote: big bus mike wrote: I don't know anyone in the VW scene that is successfully running a twin-turbo system. There's got to be a reason.

Not saying I don't agree with you on what you said, but there was a '59 beetle vert at Bug Jam last year that had a twin turbo type IV in it.

This car belongs to Steve and his son Jemery in So. Fla. They still dont have it dailed in yet. And keep in mind Steve is a God Dam genius! GOOD LUCK

Mon May 26, 2008 5:51 pm

Andrew wrote: big bus mike wrote: It just goes to show there are people with more money than sense...

Actually, they only thing they had money in was the parts, if I remember correctly. It was a father son deal and they did the whole engine setup themselves. Custom made the manifolds, even. It was very, very cool. I spent a good bit of time looking at it. I was impressed.

It looks really well done. The thing I don't understand is why have two separate turbos that appear to feed into a single plentum? On a modern fuel injected car it could be rather easy to control (the 2.7L bi-turbo Audi's for example) but I would imagine it would be a bit difficult getting it set up correctly.

Now to the original question of two turbos, each feeding a dual barrel carburetor, you're asking for trouble, and if you have to ask questions about the idea, you don't have what it takes to make it work. I don't mean to sound like a dick, but it's going to require a lot more mechanical aptitude than just welding some pipe together, bolting on a pair of turbos and calling it good. It might not hurt to make friends with the guy with the twin turbo oval.

Mon May 26, 2008 9:46 pm

[/quote]

What's the point? Even the type IV can handle only so much boost. Just one of those turbos could make more boost than that engine could normally handle without drastically lowering the CR. Lets see.... Type IV engine, bergman (whatshisface) porsche fanshroud w/alt, 2 turbos, custom (and chromed) intakes, custom exhaust, LOTS of braided lines, custom electric ignition, custom ground cams, and whatever else he has in there (perhaps something to keep this monster cool?). Sounds to me like there's a small fortune in there even with the homebrew stuff. A well-tuned single turbo upright setup would serve the same purpose without the added cost (keep in mind that you'd probably be outsourcing a lot of the work this guy did himself).

There is one advantage to the TT setup though.... It's super reliable. You can always rely on it sitting there all blingy on the back of a trailer with a big goose egg on the odometer.

Mon May 26, 2008 9:59 pm

big bus mike wrote: It looks really well done. The thing I don't understand is why have two separate turbos that appear to feed into a single plentum? On a modern fuel injected car it could be rather easy to control (the 2.7L bi-turbo Audi's for example) but I would imagine it would be a bit difficult getting it set up correctly.

They aren't feeding a single plenum, they're being drawn from a single plenum. It's a draw through setup with the throttle body is mounted to the firewall behind the fan shroud.

Mon May 26, 2008 10:29 pm

Try here...........

http://www.shoptalkforums.com/viewforum.php?f=3

Tue Jun 24, 2008 8:49 pm

glowplug wrote:

What's the point? Even the type IV can handle only so much boost. Just one of those turbos could make more boost than that engine could normally handle without drastically lowering the CR. Lets see.... Type IV engine, bergman (whatshisface) porsche fanshroud w/alt, 2 turbos, custom (and chromed) intakes, custom exhaust, LOTS of braided lines, custom electric ignition, custom ground cams, and whatever else he has in there (perhaps something to keep this monster cool?). Sounds to me like there's a small fortune in there even with the homebrew stuff. A well-tuned single turbo upright setup would serve the same purpose without the added cost (keep in mind that you'd probably be outsourcing a lot of the work this guy did himself).

There is one advantage to the TT setup though.... It's super reliable. You can always rely on it sitting there all blingy on the back of a trailer with a big goose egg on the odometer.

Not to bring up an old post but no its not some bergman shroud, its actually a one off shroud so that we could push the fan back far enough to clear the deck lid. Thanks for the compliment on the intakes, I put about 20-40 hours sanding and polishing those things to get them to that point. To bad we scraped it and went to a blow through setup so I had to polish them all over again. You can see it featured in the august issue of Hot VWs.

big bus mike wrote: It just goes to show there are people with more money than sense...

Whats that suppose to mean? Were you there helping us build it?

Tue Jun 24, 2008 10:09 pm

Cool, I'm really glad this one came back up b/c I have to admit I have been back to this thread more than a few times simply to stare at that engine :shock: . I'm not hating this at all, but I do have a few questions for you: Is there any particular reason you went with two turbos over one? If it's b/c 'it's never been done before', that's awesome. Maybe it's a type 4 thing (admittedly I don't know much about this engine)? Boost? CR? What are you using for overboost protection? Now that you are using blow-through, are you using a carb or TBFI?

Sorry about all the questions but I love turbos on aircooled engines and have never seen anything like this before. Also, I can't wait until the mag gets here. If it works, is reliable, and has advantages (quicker spool-up maybe?), who knows.... I'm not set in my ways yet. I saw your gallery too. Great job on the shroud. Can you buy the fan/alt seperately? :wink:

Tue Jun 24, 2008 10:49 pm

glowplug wrote: Cool, I'm really glad this one came back up b/c I have to admit I have been back to this thread more than a few times simply to stare at that engine :shock: . I'm not hating this at all, but I do have a few questions for you: Is there any particular reason you went with two turbos over one? If it's b/c 'it's never been done before', that's awesome. Maybe it's a type 4 thing (admittedly I don't know much about this engine)? Boost? CR? What are you using for overboost protection? Now that you are using blow-through, are you using a carb or TBFI?

Sorry about all the questions but I love turbos on aircooled engines and have never seen anything like this before. Also, I can't wait until the mag gets here. If it works, is reliable, and has advantages (quicker spool-up maybe?), who knows.... I'm not set in my ways yet. I saw your gallery too. Great job on the shroud. Can you buy the fan/alt seperately? :wink:

Well for one me and my old man were tired of seing the same standard single turbo setup and we wanted to be original, and we figured that it would be easier to plumb. We went with a type 4 because we wanted it strong and reliable which it is. Were throwing about 12 pounds of boost at it right now and shes holding just fine and makes boost pretty fast. CR is about 7.5:1. Over boost protection are the two waste gates. Were using the same throttle body when we converted to blow through. The heart of the system is an electromotive ECU that controlls our fuel management and ignition. No worries on all the questions it doesnt bother me :wink: We bought the fan and alt together off thesamba actually :) I dont see why they could not be bought seperately. If you look close at the pictures in the mag you can see we made the shroud from two pieces, I havent updated my gallery in a while.

Mon Jun 30, 2008 7:56 pm

Got my mag yesterday. I have to say that thing is HOT!

Ok, let's talk about the car now :wink: (you're probably getting that a lot by now). Seriously, nice work! I'm even digging the water-cooling setup. After seeing the mag, I still can't say that I'm sold on the twin idea but I honestly never thought it would be plausible until now. Then again, even fuel injection was a myth once- just took somebody to say 'fuck the myth'. Hopefully I'll see this monster a a show or two next season. Keep it up. 8)

Tue Jul 01, 2008 8:27 am

Thanks, were talking about it here

http://www.shoptalkforums.com/viewtopic.php?t=114598&start=105