911SC (with CIS to EFI) Turbo Conversion - Page 2

tbitz · 06:21 AM

I got some flow numbers for 7psi and 10psi with and without intercooler and plotted the line through the graph. Note at 2500rpm you won't be getting full boost so the line should curve down.

tbitz · 03-26-2004, 06:29 AM

tbitz · 03-26-2004, 06:35 AM

The center island of the GT-32 looks to be 76-77% eff where the center island of the T04E-54 looks to be 78% so infact the T04E-54 has a higer efficiency that the GT-32

The operating points look to stay longer in the center island on the TO4E-54 than the GT-2. Also note that at the 30lbs/min(7psi) and 34lbs/min(10psi) the eff is better on the T04E-54 than the GT-2.

So It seems to me that the T04E-54 is a better choice if you are going to run 7psi -10psi boost.

tbitz · 03-26-2004, 09:13 AM

Here is one more. The T04E-57. Less desirable than the 54 trim, but there are a few new hybrid ones on ebay right now with a $395 buy-it-now. Very tempting but I' m going to hold out for that 54 trim.

RarlyL8 · RarlyL8's Garage

What about the K27-7200?
This turbo is standard issue on upgraded 930s. I'd think an SC engine at 3.0L with SC cams, backdated exchangers and SC compression should work really well with that unit. I've got SC cams in my 930 engine with this turbo and absolutely love it.
Disclaimer - I don't know squat about those funny geographical landmass pictures you fellas keep posting. Just a real world / real application data point.

Natchamp · 03-26-2004, 03:59 PM

I wish we had a map of that K27-7200, it would be very interesting to see how it compares.

ohecht · 03-26-2004, 05:49 PM

What are the options for a kit like this for an SC motor with a 9.3 to 1 compression ratio without opening the case, etc.? With and without intercooling?

Based on the apparent craftsmanship on the EFI kit, I am really excited to see what you come up with for the turbo kit. There should be a ton of room for an intercooler after installing the EFI kit, and maybe you could work one into the LR wheel well, too.

Olivier

tbitz · 03-26-2004, 06:20 PM

Can't understand why they keep the compressor map secret. How are guys supposed to figure out which one works for their setup?

I'm figuring they have seen the maps of Garrett and KKK isn't quite upto par so they hide their poor data.

89turbocabmike · 03-26-2004, 07:09 PM

Tony, how applicable will your efi kit be to those of us with factory CIS turbos? Obviously intakes are different, but I'd be willing to handle that aspect(injector blocks/fuelrail). There are a couple of fairly "inexpensive" new efi set ups (www,patwilliamsracing.com) to bolt onto the stock turbo intake thus avoiding the modded carrera intake and custom intercooler et al, however they are still 6K plus installation. I'm also interested in twin-plugging so does megasquirt have that ability?

tbitz · 03-26-2004, 07:21 PM

My CIS to EFI injector bungs don't work on the 930 intakes, so you need a solution there. I've see Pat's website and the CNC injector blocks look nice (I'm sure they are not cheap).

If you solve that problem, then you're 90% there. All you need is the MegaSquirt ECU and some sensors.

In my kit, the MegaSquirt doesn't do ignition. There are spin offs of MegaSquirt that can do ignition advance/retard and fuel in one unit. I will be looking into this. It still uses the distributor, but allows you too advance/retard the timing based on rpm and boost. You need some pickup though.

1fastredsc · 03-27-2004, 09:15 AM

What about using a 930 distributor on an sc that's turbocharged? Would that be feasibal?

tbitz · 03-27-2004, 09:44 AM

Quote:

Originally posted by 1fastredsc
What about using a 930 distributor on an sc that's turbocharged? Would that be feasibal?

My setup will require that the car have done the CIS to EFI conversion first. This solves a lot of problems and really simplifies the conversion. With CIS you end up with hoses and fuel lines all over the place making the engine bay look like it is in intensive care

Folks have done the conversion with CIS and I admire them, but EFI is waaaay easier IMO.

1fastredsc · 03-28-2004, 08:36 AM

I think you missed my statement tony, i said what about using a 930 distributor for the ignition. I'm assuming another issue with higher boost is retarding the ignition properly for boost. So would a 930's distributor solve that problem?

tbitz · 03-28-2004, 08:43 AM

Sorry. When you said distributor, I though you meant fuel distributor.

I am looking at using the MegaSquirt to do the ignition retard, but another option is to use a MSD boost retard unit. Don't know what a 930 ignition distributor costs, probably big $$ and how flexible is it really?

1fastredsc · 03-28-2004, 01:34 PM

I'm not positive, that's why i asked. I just figured a used 930 distributor would fix the problem. Maybe the existing sc distributor can be modified to retard under above atmospheric conditions?

dean · 03-28-2004, 04:58 PM

Quote:

Originally posted by 1fastredsc
I'm not positive, that's why i asked. I just figured a used 930 distributor would fix the problem. Maybe the existing sc distributor can be modified to retard under above atmospheric conditions?

Most 930 distributors don't retard on boost. They retard with vacume. The late US distribs do retard on boost and vacume

RarlyL8 · RarlyL8's Garage

The factory manual lists the advance curves for all 930s. As Dean stated the early ones don't retard, they just flatten out on the advance curve. The ROW model is most desirable with the California unit being the most conservative curve.
The SC dizzy with dual vacuum ports is similar to the California 930 dizzy in function. One of the ports pulls down advance near idle for smog purposes.

ohecht · 04-27-2004, 04:15 AM

Not sure if you guys with 930s saw this, it is a site with 930 injector blocks (6 for $350). (bottom of the page)

Olivier

http://www.goingsuperfast.com/FORPORSCHE.html

RickM · RickM's Garage

Wow, good find. That intercooler is downright inexpensive.

RickM · RickM's Garage

BTW, he also has a few different versions of quick release steering wheel hubs.