930 Twin Turbo CIS engines........right here

[Craig 930 RS]

21 years ago, check out the location of the CIS fuel head and metering unit!

http://www.dp935registry.com/gifs/935DP_Rossatti_rr_24-87.pdf


And another from the past:



Brian, this might help you with your TT endeavor -

[sand_man]

[RarlyL8]

That's pretty radical all right. Thanks for posting!
Do you have any more pictures of the engine you posted above? It looks like a stock 930 CIS manifold is used but I cannot make out the path from the air meter valve to the turbo inlets.

I have a few pictures taken a year or so ago of some CIS experimentation I did on the evil engine. The component construction of CIS allows things to be moved around a bit. I wanted to get the system running before I posted the pix but that has been indefinitely delayed by muffler work.

[Craig 930 RS]

I've asked the guy from Germany for more information - stay tuned!

[WydRyd]

I like it! I like the exhaust setup too

[beepbeep]

Porsche used K-Jet on 934 beacuse regulations didn't allow anything else. But they had two of them, as one was choking too much. I saw turbocharged cars running pressurized Weber DCOE:s as well...you can make all kind of weird mixes with old technology but you cannot beat the fact that K-Jet is still inferior fuel system after certain amount of HP is exceeded.

[WydRyd]

The inlet tank looks interesting... nice flow into the IC... should give nice distribution across the core

[BoxxerSix]

Originally Posted by WydRyd

The inlet tank looks interesting... nice flow into the IC... should give nice distribution across the core

.....abeit with alot of turbulence though. Two round ~2" tubes dumping into an open chamber endtank with little to no transition...ehh so so, but again we're looking at pictures of old technology here

[copbait73]

In CIS cars this twin installation requires relocation of the oil tank to the one year only '72 configuration- a very expensive proposition. Though great looking on the bench, the configuration is a non-starter for this reason alone.
The distributor is 964 twin therefore not sure about the base engine. 930 tein plugged or 964 with intake backdated?

[WydRyd]

Originally Posted by copbait73

In CIS cars this twin installation requires relocation of the oil tank to the one year only '72 configuration- a very expensive proposition.

Why's that? Isn't the 930 oil tank in the same location as the Carrera oil tank? On the right side of the engine bay? You can do a simple mod to the oil tank to make room for the right side turbo. I had this done by ProtoTech for my upcoming TT conversion

[RarlyL8]

When I did the 993tt H/E mock up on the Evil Engine there was a clear interference on the right side with the oil tank. If you made a big enough dent in the tank allow room you would still be left with an extremely hot turbo right next to your oil tank.
Does PtotoTech offer a heat shield as well?

[WydRyd]

Hmmm.. no heat shield, but they welded a bracket on the oil tank, which kicks out the bottom of the tank a bit to make room for the right side turbo. I guess it wouldn't be hard to fit a heat shield around that turbine housing for extra protection.

They have run all shapes/sizes of turbo's in that location without any issues, as does Protomotive

[AngM018]

I know this is on the back burner for your Brian, but when you do get back to it, why not just relocate the oil tank? are there issues associated with the relocation other than just having to run longer oil lines?

Since we are speaking of an air cooled engine, I personally wouldn't want any unnecessary heat too close to the oil tank, even with a turbo blanket.

It may look kinda fugly, but an oil tank in the trunk with a bunch of heat sinks and maybe a fresh air hose directed at it would help in my eyes. I know, I'm always over the top!

[RarlyL8]

My car is 95% street so I don't want an oil tank in the trunk.
Those 993tt H/Es belong to Lukesportsman. The exchangers and headers I have are all rear exit. I also like the cool factor of rear mounted turbos. It makes no sense to use twins on a CIS engine so the cool factor trumps.
I see no time for that project in the near future so in the mean while I'll keep gathering data and ideas.
Merv can you post a picture of the Protomotive oil tank mod?

[Craig 930 RS]

This Evil stuff will get lost here......I'd move it to the Evil thread -

In the meantime, I've got more TT CIS goodies coming ;-)

[Craig 930 RS]

"It makes no sense to use twins on a CIS engine so the cool factor trumps."

So you're doing this all for looks?

Despite the apparent dichotomy of 'twin turbo' and 'CIS', there is still gains to be had from a twin turbo setup.
Higher HP, boost at lower rpms, and better 'response' are the main ones -

[Craig 930 RS]

How do I take a picture from a Microsoft Word document -- to get it here on this post?

[beepbeep]

Originally Posted by Craig 930 RS

"It makes no sense to use twins on a CIS engine so the cool factor trumps."

So you're doing this all for looks?

Despite the apparent dichotomy of 'twin turbo' and 'CIS', there is still gains to be had from a twin turbo setup.
Higher HP, boost at lower rpms, and better 'response' are the main ones -

Hmm...it's not all rosy. You need twice amount of turbos, some clever Y-plumbing, higher HP is not at all guaranteed (unless going for some wicked HP which CIS won't support anyway) etc. Yes, you can shorten the path from heads to turbos, OK.

Responce is not guaranteed either...small turbos in consumer price range aren't as efficient as bigger ones. Yeah, you can probably find some nice Garrett GT18's to go there and have wicked response but, IMHO, fitting twins to CIS is a non-trivial task and not-efficient moneywise either.


In the end, once you bought two "quick turning small but efficient" turbochargers, welded all custom Y-plumbing around CIS, made those custom headers and in the end made it all work you would spend twice the money it would take to slap MSII, six injectors, reweld the turbo flange and install single GT35. And probably make less power too.

"Oh but it takes knowledge to install MS" you say? Well yes, but it also takes knowledge to make CIS work with such setup. Remember, it's CIS cone that represents mechanical "VE-table" and is inherently non-adjustable. Slapping twins on it might bump VE for engine out of whack and then there is nothing to do except fitting custom enrichment (that needs to be programmed too).

So yeah, nice exercise in creativity but not terribly effective I must say.

[Craig 930 RS]

No, not terribly effective (objectively, whatever that means) no of course not, and of course EFI is better......etc -

But as a general rule 2 turbochargers on a flat six can make more power at less boost than a single.

EFI or not, CIS or what have you - any modification modestly outside the normal design range will result in optimizing the system as a whole - hell, I had to do this on my CIS motor.

A CIS motor - mine in particular - has waaay more than enough fuel, bottom to top, at 1.0 bar, and over 500 FWHP.

Thus, I'd love to see a contemporary CIS engine which utilizes the Leask RPM switch / WUR / IA fuel distributor to see what is can do.

I suspect quite well -
------
So how to transfer a picture from MS Word into a gif or .jpg?
I have yet another completely different CIS TT motor picture to post

[RarlyL8]

I'm doing it simply because I can.
HP is not the goal, only torque and quicker spool. The cool factor is the inspiration. You don't see CIS twins every day.
The cost will be very minimal due to me doing the work. I have the headers to modify and the turbos and the waste gate(s). The rest is just plumbing. There shouldn't be more than $1000 in it when I'm all done.
Of course it needs to function well. If I can't make my custom CIS do the job it all comes off and will be parted out. Consider it cathartic and move on.

Looking forward to the pictures Craig.
If you convert the Word document to a pdf you can post it.