Advice on an EFI setup on a 2,7 (1977) 911/81

[SorenDK]

Hi

I need some advice from guys out there who have knowledge on the EFI setup.

Recently I purchsed a 1977 with a 2,7 cis and coming from a 1969 E model with webers this i kinda new: Im planning to replace the old CIS on the 2,7 with some EFI and need some advice on setup. Basically Im trying to figure out the optimal setup in terms of what efi kit, inlet manifold, throttle body to use?
The engine is a 911/81 RoW with stock CIS at the moment... how should this be configured?.... I thinking about JE pistons with a custom cam... any advice on that?

Anything else I should be aware of... what about oilpump/lubrication/cooling... does stock suffice?

And of course - anyone have an idea about HP outcome ?? - coming from stock 165 it would be nice with some more :-)

Thanks :-)

Best from Søren

[dfhtrhjn]

I've only met a couple people with EFI and they used the Bitz Racing EFI kit for their 911s. I'm told it self configures, you can choose your fuel mappings, and a novice can put it together in a few days.

If my CIS ever totally takes a crap that's what I'll order.

[Eli W]

Why not just do PMO Carbs? Not being flippant, I have a 3.2 engine with 964 cams and twin plug running on a CIS and if it craps out I'm planning to go PMO carbs. Unfortunately it runs like a top, and goes like hell at 3,500 rpm and above. It is not broken so I can't fix it.

[dfhtrhjn]

He could still pass emissions requirements with EFI but not with carburetion I'm guessing.

[Eli W]

Yeah, that would be a good reason. I got my hotrod out of Cali because of their emissions.

If it could have pasted emissions there I bet my car would have been 5k more.

[SorenDK]

Emmision is not really an issue since I dont live in cali but in Europe...:-)
Anyway the carb thought passed my mind coming from a 69 with webers but i think it must be worthwhile introducing the good ole flat 6 intake system to 40 years of Tech evolution. I have heard many good things about the EFI - megasquirt and so forth. Say I go with the kit from bitz... Should I consider another engine setup?... Cams, pistons etc...

[Tippy]

Read the MegaManual from MegaSquirt.

DIYAutotune.com sells complete MegaSquirt ECU's and harnesses for cheap.

[dfhtrhjn]

Going with different cams and/or pistons would require pulling the engine. If you're interested in a big project, you could get a lot more power from that motor. The efi would really let you take advantage of it.

Either way efi is going to give you more power because you can select a fuel mapping that gives you more power at the expense of fuel economy if you choose. I've been told by the couple people I've met that efi provides better throttle response too.

I guess if I were you, I would do an efi conversion of your choice first, and if you're still itching for engine removal, you can always do the cams later.

[ThomO]

I have been doing some research on the topic and bitz racing seems to be the way to go for a cis to efi swap.

I am looking to put 2.4 heads and cylinders on a 2.0 with PMO ITB's Megasquirt EFI and some type of coil on plug setup just to play around with new tech on an old engine

[SorenDK]

Brillant inputs guys - thanks. Dont mind pulling the engine but will go with dfhth and try EFI with current. ThomO... Sounds interesting... I was thinking maybe some JEs with a modified cam could be fun...

[roy gray]

carbs are always a step backwards.why is that so hard for porsche guys to take.if you have cis,and it works properly,keep it.if you want more performance,go with cam,piston,and head mods.or a bigger,better motor.if you have a 2.7 or 3L with cis and you have money go with some fancy efi setup.but at that point,why not update yer stock cis motor with a sweet 3.6 upgrade?every time i've put carbs on someone's otherwise reliable cis motor,because of someone else's advice,they were not impressed."why won't my car run cold?why does my car backfire?why does it idle like ****?it didn't used to....."the answer,carbs-just say no.this semi-rant applies only to road cars,drivers.

[al lkosmal]

Soren,
Greetings. I have a little experience with installing and tuning EFI on 911 engines. Let me know if i can answer any questions. A lot of it depends on what you want to do, budget, etc. The nice thing is that you can step into it somewhat progressively, improve performance one step at a time...but keep in mind that it is a system, so think ahead regarding the final configuration.

Here's a couple of pix of my current project:

2.7 normal engine
7R case.
Heads ported to 36mm
9.5:1 JE pistons
Early S spec cams
headers
EFI/ITB system ( I have two to choose from...an old Hillborn mechanical injection system that I'm modding to work with EFI injection or TWM 3003 44mm ITB system)
3.2 Motronics ECU






My 1st kit was a Tbitz kit and I recommend Tony's kit highly. If you want to enter the EFI world, relatively inexpensively and without dropping the engine this is a good way to go.............but there are many ways to go.

Once I started with EFI...I quickly went down the slippery slope and designed a kit that adapts Triumph Speed Triple ITBs to 911 manifolds, etc. I used Megasquirt for the ECU numerous times.

Here's a link to some of my projects. Quite a few are EFI/ITB systems...from stock 2.7s like yours to some slightly wilder hot rod motors.

https://www.youtube.com/user/koz77911

This should provide some food for thought.

regards,
al

[SorenDK]

Thanks guys

Returning to your post since I appreciate you inputs. Actually did a full rebuild of my engine so now I have the following setup - still a 2,7 litre...
JE 10,1:1
New Mahle cylinders
DC-20 cam
Rest is pretty much stock besides oil fed chain tensioners.

I started off mounting a CIS from a 3,0 litre '78 but I find this difficult to dial in. Still needs some testing to do but idle is a pita. Hence EFI is getting closer.
I want to build a street car - not race or track - and my objective is to outrun all the SCs in the neighbourhood :-)... Pretty ambitious I know ...haha.

Jokes aside - I'm planning on reusing the CIS plenum air filter / throttle setup but obviously deleting air mass sensor, fuel distributor etc. I am trying to keep budgets low - and as Al writes - working progressively meaning I want to start with basics and build on that. Mega squirt sounds appealing, so I planning on this setup... Any thoughts on that? I am presuming lots of parts and sensors are available from other car manufactors... Injectors, sensors etc. Has anyone experience with this?

As you can understand I'm collecting parts ... Does anyone know of places to look? - or have anything I can buy?

Thanks ...

I'll try and post pics... :-)

[SorenDK]

[SorenDK]

[Cervantes911]

Originally Posted by SorenDK

Thanks guys

Returning to your post since I appreciate you inputs. Actually did a full rebuild of my engine so now I have the following setup - still a 2,7 litre...
JE 10,1:1
New Mahle cylinders
DC-20 cam
Rest is pretty much stock besides oil fed chain tensioners.

I started off mounting a CIS from a 3,0 litre '78 but I find this difficult to dial in. Still needs some testing to do but idle is a pita. Hence EFI is getting closer.
I want to build a street car - not race or track - and my objective is to outrun all the SCs in the neighbourhood :-)... Pretty ambitious I know ...haha.

Jokes aside - I'm planning on reusing the CIS plenum air filter / throttle setup but obviously deleting air mass sensor, fuel distributor etc. I am trying to keep budgets low - and as Al writes - working progressively meaning I want to start with basics and build on that. Mega squirt sounds appealing, so I planning on this setup... Any thoughts on that? I am presuming lots of parts and sensors are available from other car manufactors... Injectors, sensors etc. Has anyone experience with this?

As you can understand I'm collecting parts ... Does anyone know of places to look? - or have anything I can buy?

Thanks ...

I'll try and post pics... :-)

Hi, I like to know if you finish your proyect!

[SorenDK]

Yeah i did actually - got it all up and running and eventually tuned running decent, however the camshafts does not comply well with a plenum intake manifold so I'm going down another slippery road - that is putting itbs on:-).
A bit of advice- if planning on including ignition on Megasquirt don't get tbitz kit unless you really like to solder and troubleshoot. It's missing half the components for ignition - especially if you are doing like me and include VE/triggerwheel :-)

https://photos.app.goo.gl/xrlB181bYUP68uWI2