My 2.7l EFI project with Carrera intake

djb25 · 07-19-2014, 07:55 AM

Hi everyone,

I'm about to start converting my 2.7l to EFI using megasquirt and a 3.2l Carrera intake, so I figured I would start a thread detailing the entire project.

This project is about 10 years in the making, during which time I've acquired a lot of random components, including intakes and random sensors, etc.

I have a mostly complete 3.6l aluminum intake (without the injector blocks), a stripped 3.0 sc intake, and now (third time's the charm) a mostly stripped 3.2l Carrera intake.

The 3.6 intake was rejected because injector blocks were too expensive and would take too much effort to fabricate myself.

I had planned on using the SC intake, and had gone as far cutting down the air box, but then I found a good deal on a 3.2 intake on eBay.

I don't know if there is any real performance advantage to the 3.2 intake, but it looks better, so that's what I'm going with.

I'm using a throttle body from a 944, as it mates to the 3.2 intake perfectly.

The fuel rails are from bulk aluminum extrusions.

I'm also planning on using the idle control valve from the 3.6 intake.

Most of the wiring, injectors, and misc. are coming from a late-model GM v6 wiring harness that came from eBay. I got the entire wiring harness, complete with connectors, so I'll be in good shape for the various sensor connections.

I'll be using an LC-2 wideband controller for the 02 sensor.

EFI will be Megasquirt 3. I haven't bought the controller yet, mainly because I'm not sure if I'm going to need the MS3x board.

The plan is to start by setting up fueling and then, later on, controlling ignition as well.

I'll post some intro photos shortly.

Sent from my iPad using Tapatalk HD

cmonref · 07-19-2014, 08:33 AM

You'll want the MS3X board for sequential operation, for the added input/outputs, and for the knock sensor board with its ability to respond to knock. You will seriously regret not getting it.

Brian

djb25 · 07-19-2014, 10:04 AM

Brian,

Thanks for the input. One of the first questions I was going to ask was about sequential injection and whether it was worth having.

Is there an advantage to sequential? Or is the knock control the real advantage?

ej911 · 07-19-2014, 11:48 AM

very interested to see this. sub'd.

cmonref · 04:11 PM

My 3.0L has MS3X, 3.2L intake, MAF, LC-1 (soon to be two), two knock sensors (one on the pads between intake runners 1-2 and 5-6), running full sequential. Sequential gives you smoother idle, NOT more power (sequential and batch are equal at high power settings). Changes in fueling are slightly more responsive since changes can be applied to the next cylinder instead of waiting until the next batch calculation (I suspect us shade-tree folk can't detect this, but I also suspect it is part of the smoothness.) In sequential, knock control can retard ignition on a cylinder-by-cylinder basis in response to knock detected on a cylinder-by-cylinder basis. For inputs and outputs, my MAF, second O2 sensor, the constant barometric sensor, and the fuel pressure sensor all feed thru the 3X card with its additional circuits for such.

In a developing system -- and MS is a developing system with 1, 2, and 3 in the field and 4 being talked about from a features basis. There are many spinoffs, like the DIY PNP units and the MS3-Pro (effectively an MS3X in a different package), from the basic series. For a system that is in continuous development with new features being introduced as the development moves forward, it is always wisest to get the most advanced package available at the time. The uses of the "full package" might not fully absorbed by the new user, but they are there.

That said, MS is a DIY system for a user committed to spend lots of time learning. And it is this learning that opens the horizons for the full capability of the hardware purchased. Tain't easy, but it is rewarding.

And there is a TON of help available here on Pelican and on the MS forums -- especially the Extra forum.

Brian

PS: DIYAutotune has 10% off thru Monday in honor of their recent speed record of 202 mph with their MS3-Pro car.

zelrik911 · zelrik911's Garage

I will follow your project with interest & may do the same myself (I am collecting parts already!).

What are you doing for ignition &/or EFI timing? M/S doesnt seem to be as advanced in this area as it is in the pure injection side.

Peter SC 3.0L

djb25 · 07-19-2014, 06:26 PM

Okay, first issue has popped up, fortunately it's nothing significant.

The injectors I have are Delphi 25323972. They're a high impedance injector that flow around 19 lbs/hr, which is about the correct flow for 200 hp.

The problem is that the tips of the injectors are wider than the Bosch injectors that porsche used on the 3.2. The through hole in the manifold is too small for the tip, so the injectors won't seat. Note that the port itself is the correct diameter, it's the smaller hole that runs through the manifold that is too small. The tip on the bosch injectors is around 10mm, while the delphi tip is around 12mm.

I can just bore out the hole, but I'm not sure if I should bother. Maybe I should just get a set of higher flow injectors?

Does anyone know if there is a standard for tip sizes?

jpnovak · 07-19-2014, 06:43 PM

Run the smallest injectors you can and still have less than 85% duty cycle. I doubt your 2.7S motor will come close to maxing out a 19# injector.

The problem with your injectors is the outer lip of the Pintle cap. You can put new pintle caps on or just shave down the outer lip just below the o-ring. It is no problem to drill the manifold injector section slightly larger.

Another option is to pick up another set of injectors. I like the EV6 style injectors that are on a Ford 4.6 GT application. They are cheap as these guys like to think that larger injectors make more power. BS. Use this to your advantage. They flow about 21# and work great. Very stable at low pulse widths.

I typically like the Seimens Deka injectors the best.

The MS3 setup is great. Be aware that the case is considerably larger than an MS2 setup. The typical installation locations are under the seat and the MS3 does not fit on a stock seat unless its a later car with the spacers. Honestly, on these cars sequential is not needed when you use a common plenum. Idle will be just fine. CIS is batch fire and no one complains about how smooth the idle is. The extra ports are nice but you just won't need them on a NA 911 engine.

Why not use stock 3.2 fuel rails? The bolt up nicely to the intake and no brackets are required. Its easy to cut the collars and plumb your own fuel system/hoses. \

Having converted a whole bunch of 911s to EFI just keep it as simple as possible. Plan ahead and it is easy to make changes/upgrades later on.
YMMV.

djb25 · 07-19-2014, 08:06 PM

Actually, it's not the lip on the cap that is the problem. It's the tip of the injector itself. The injectors are the disc type, so maybe that's why they're larger?

This is what my injectors look like - http://www.summitracing.com/parts/dfp-fj10480

I'm probably just going to bore out the manifold to accommodate the injectors I have. They're practically brand new, so no reason not to use them.

Oh, and I'm using the extruded fuel rail because I already have it (and I don't have the stock 3.2 rails).

So where is everyone mounting the ms3 box?

scottrx7tt · 11:21 PM

I am running a 3.2 intake on my 3.0 motor. I am using the 3.2 throttle body, from what I understand, the 3.0 throttle body is plug and play also. If you use the 944 throttle body, you may have issues hooking up the throttle linkage. I am also running the stock fuel rails, and fuel lines. No since in trying to fabricate everything up, if it's already made up for you. I am running some accel fuel injectors, that are exact drop ins. Check out the Bitz website for the part # that you will need. I am running the Bitz megasquirt ECU. It's a little basic, but I liked the idea of the ECU already tuned. I ended up having to tune it anyways, since my car would not run off the programmed tune. You can also use the carrera ICV instead of the 3.6 ICV, which would make for an easier install. I am using the one from the 3.0, which is a little archaic, but seems to work OK

scottrx7tt · 07-19-2014, 11:18 PM

Here's a pic

djb25 · 07-20-2014, 07:00 AM

Well, it appears that the injectors will fit if I remove the pintle caps. Although, "pintle" caps isn't really correct, as my injectors are "disc" type - not pintle type. I think I'm just going to leave the caps off and try to run that way. Apparently this comes up on occasion - the bosch tips are significantly narrower.

As for the throttle body - I didn't know the 3.0 and 3.2 throttle bodies were "plug and play" with the 2.7 throttle linkage. I'll have to look into that once I pull my cis intake. I had the 944 throttle body in my random collection of parts, but if it proves difficult to adapt, I'll look for an alternative.

The 3.6 and 3.2 idle control valves are more or less identical, so no issues there.

Admittedly, this would be much easier if I had a complete 3.2l intake. However, I'm doing this for "fun" - not out of necessity - so I'm ok with putting in some extra time.

I'm also considering powder-coating or cerakoting the intake in silver or a light gray, just to dress things up a bit.

I'll post some initial photos soon, I promise!

djb25 · 07-21-2014, 02:40 PM

Well, I got a bit of work done on Sunday.

The fuel rails and mounting brackets are completed and the rails are now attached to the intake.

Today I ordered the Ms3 with ms3x expansion, a wiring harness, and some weather pack connectors from diyautotune.

I think I'm going to use Fragola 6000 series fittings and the Fragola -6 AN PTFE fuel hose. I was going to use a nylon or Kevlar wrapped hose, but I couldn't find any with Teflon cores, so I'm going to use the Fragola hose with the plastic coating over the stainless steel.

I chose the Teflon hose as it seems essentially bullet-proof and impervious to pretty much all fuel formulations.

djb25 · 07-21-2014, 06:09 PM

Here are a few "in progress" photos:

Intake with newly completed fuel rails:

Intake mocked up with 964 idle control valve and 944 throttle body:

Obligatory "before" shot of the engine bay (or possibly "back when the car ran"):

And this is a full body shot of the patient, my '77 911S:

djb25 · 07-26-2014, 07:47 AM

Okay, here's a progress report. I've gotten a bit done over the last few days.

Before:

After:

It fits, anyway:

Obviously I pulled the engine shroud. I polished it up a bit and it is now looking quite nice.

Now I'll have to do a bit of cleaning.

The only problem I've run into is the return line.

I bought a -6 to 14.5mm (female) fitting from Earl's but it isn't going to work with the factory fitting.

I know some people have stripped the factory fitting and reused it, but I am using Fragola PTFE hose and fittings, so I really can't. I guess I could use rubber hose to make a short adapter from the factory fitting, but the point of the PTFE was to have "lifetime" fuel lines that I didn't have to worry about failing from ethanol and so forth.

Does anyone know where I can get an adapter for the factory connection? Does anyone even know what the factory connection actually is?

911pcars · 07-26-2014, 08:30 AM

Contact Len (aka BoxsterGT). He supplies hose, tubing and fittings for what you need.

Sherwood

cmonref · 07-26-2014, 09:01 AM

What are you planning to do for the essential wiring for the MS? Where will you mount the MS3, how will you run the wires from there to the engine, how will you run the wires on the engine? It looks like you are doing the intake installation first without removing the engine and without doing the basic wiring.

I found that the basic wiring was only really possible with the engine removed. And the wiring ON the engine was only possible with the engine on an engine stand. I would hate to try all of that with the engine in the car, even with the engine partially dropped.

Brian

djb25 · 07-26-2014, 10:21 AM

Hmm... I'm not quite sure why I would need to remove the engine to take care of the wiring. It would likely be easier with the engine removed, but as the full car shot suggests, I'm a little short on space. Couple that with the fact that the windows are out of the car (roof respray is pending) and you can probably guess why pulling the engine isn't on my list.

I have pulled the engine a bunch of times, but that was back when I had access to a very large garage. I'm really not concerned with working with the engine in the car - the intake came off fairly easily, and that is probably the most difficult part.

cmonref · 07-26-2014, 03:05 PM

Damion,

Possible with the engine in place, yes, but might be difficult to a fault. From the pix below, you can see the two 3/4" wire bundles that come from the MS3 to the engine (extreme right near the shock tower, tied with white tie-wraps), the bundle of unused wires in the far left forward corner, three bundles handing down that connect to quick-disconnects on the engine, the power panel with new fuses and relays. One picture shows the engine quick-disconnects for the three connectors and the manifold vacuum line -- the number of connectors in the picture shows how many wires have to go onto and around the engine (not including the OEM stuff that goes thru the 14-pin connector.) And one picture shows how busy the front side of the intake is with fuel, electrical, vacuum, and oil breather lines.

Your lack of room certainly crimps what you can spread out to do. But the electrical wiring will probably be more than you have assumed.

On a different subject, with the intake and phenolic spacers in place, have you looked down thru the injector bores and noticed that the SC intake opening blocks some of the spray pattern of the electronic injectors? You might want to widen that intake opening some, but still leaving you enough gasket area to seal the intake to the head.

Good luck! Will be following your thread with great interest.

Brian

djb25 · 07-26-2014, 06:29 PM

Hmm... I take it you're controlling ignition and fuel? Adding ignition to the mix certainly increases the amount of wiring.

I'm only setting up fuel (for now). I'll most likely go to ignition control at some point, but that will be down the road. I already have the electrical laid out, and I will do most of the wiring with the intake off. There really isn't that much wiring for fuel control.

Plus, I'm pretty accustomed to working in the confines of the engine bay.

The 2.7 intake ports are somewhere around 37mm (or there abouts) and the Carrera intake is, I think, around 40mm. Maybe it's 42mm. Anyway, I'm making aluminum spacers to blend the two together. I'd rather not grind on the intake while the engine is assembled. It's a bit of extra work, but I have a small mill so it's not a huge deal.

However, I may end up having to enlarge the cut out for the injectors.