2.7l turbo megasquirt help needed

[djb25]

Anyone out there interested in taking a look at my MSQ and seeing if I have any major mistakes?

I have a 2.7l with a K26/6 turbo. I'm running MS3/MS3x with LS2 coils. 36-1 crank wheel, so batch fired.

The car runs, but autotune makes my VE table a huge mess every time.

Also, the idle isn't very smooth, but more annoying is when I free rev the engine. It really stumbles returning to idle. Sometimes it even stalls. I have no idea why it does this or how to fix it.

I do think my injectors are too small - they're 200cc/hr and I should probably be quite a bit larger. But I don't think this would cause the idle problems.

Anyway, here's a link to my current MSQ.

[Raceboy]

Several notes:

1. You need at least 300+cc injectors, 20cc are barely enough for normally aspirated engine.

2. Your turbo is too small. It is too small for even 944 2.5liter watercooled engine let alone 2.7liter 911 air cooled one. Reason? Simple, 911 engine is much less tolerant to backpressure which leaves more exhaust gases in the combustion chamber resulting less performance and lower knock resistance.
The least you could do is to get K26/8 but even that is barely enough regarding compressor. Best compromise (note the word compromise) would be K27/8.

Do you have cut fuel lower than xx kpa setting and is it enabled? If so, set the value to 0 as that tends to make 911 engines stall especially if you do not have proper PWM idle valve.

[djb25]

Anyone have a suggestion for inexpensive injectors?

I'd like to stick with the connectors I have if possible. I'm currently running these Delphi injectors:

[turbobrat930]

These guys are the best in the business, but a 100LB injector might be too big for what you need. What is your max boost that you will be running?

http://injectordynamics.com/

Who is tuning your engine? Are you relying on the auto-tune feature to completely tune your car? If so, I would suggest finding a reputable tuner in your area, or at the very least, get some books and educate yourself on the basics of tuning, turbocharger theory (reading compressor maps, turbo sizing, etc), and understand that auto-tune is a feature, but not something that I would use to tune an air cooled 911 engine. Also, understand that air cooled engines require running a tad but richer than a water cooled counterpart. Also, EGT's are a huge concern while tuning as well.

Here is another place to get injectors, if 100LB ones are too big. I have the ID1000's from Injector Dynamics, and I will be going to ID1700's soon. The idle with the ID1000's is awesome!! idles better then my factory CIS did.

Here is the link to the other place I was talking about..

https://www.fiveomotorsport.com/fuel-injectors/

['76 911S 3.0]

You could use Hemi 5.7l injectors...they are 300cc and dirt cheap. I am currently using them on my engine and have personally flow tested and monitored the spray pattern, which is quite nice. I would offer you mine since I am swapping for ID725's but they are already spoken for.

[djb25]

Well, I wasn't sure what OEM type injectors would meet my criteria, so I went ahead and ordered a set of Accel 48 pounds/hour injectors.



So... 48 lbs/hr or about 500cc/hr, which should be good for up to 400 hp.

I'm pretty sure those are just rebranded Bosch injectors, but they seem to have the same connectors as my current injectors, which will be nice (if I'm right).

I just wish I would have realized how small my injectors were when I started the turbo conversion. I had completely overlooked that.

[djb25]

Okay, quick update just in case someone finds themselves in the same exact situation as me.

The injectors I bought from Accel are actually branded as "Deka" and use USCAR connectors.

I'm guessing these are the Siemens-Deka injectors that everyone likes. They were only $40/each from Amazon, so the price was right... except that I had to buy an eight-pack, so they were really closer to $50 each.

Apparently EV6 is often used as the name of the connector, but that is incorrect, as EV6 injectors do not necessarily have to have the USCAR connector.

My old Delphi injectors had some sort of Delphi-specific connectors, which I should have realized (but didn't until yesterday).

So now I have my 48 lbs/hr injectors, but I won't have connectors until tomorrow. Oh well.

Here's a pic of the new vs. old injector:

New injector is on top, old is on bottom.

On the plus side, I now have brand new injectors and one less thing to worry about.

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