Going EFI

[SteamWolf]

Hi all,

converting to EFI is something I will do to my SC after the SM1000.  I know others are interested in this, and Uncle has kindly done a lot of R&D already.

 

I thought I'd start an all-in-one thread here about the process.

 

It seems the most straightforward way is to use a 3.2L manifold and injectors, and either the stock ECU or replace it with a more versatile aftermarket one.

I have seen the 3.2 manifolds range in price second hand from $500 for a bare one, $1200 for a dressed one and $3500 from a local Porsche wrecker.

 

I have also found a guy in the US that makes plug in adaptors and rails to fit EFI injectors into the stock CIS manifolds. This would be the cheapest method to get a functioning system but still relies on the awful plastic throttle body plenum and hose clamped runners.

 

There's a few ITB suppliers too, ranging in price from $2500 to a NASA budget.

 

My personal shopping list is:

• either a 3.2 manifold or a custom one (probably work out costing the same),
• Haltech ECU,
• 32 tooth pulley and crank angle sensor (CAS)
• Distributor blanking plug
• 6x LS1 coils (already have)
• Oxygen sensor bung to be welded in the cat bypass,

This also means I can go turbo later on very easily (already have an 044 fuel pump fitted).

 

Thoughts? Anything I missed out?

 

Please add in interesting links, suppliers or ideas for your own EFI projects!

 

 

[smule]

Have you considered the other side of the coin... going carb with a set of PMO's ?

[wasserkuhl]

There was an article in the Excellence magazine a while ago about this.

 

I think it was sourced from this crowd, or this maybe the guy.

 

Seems keenly priced:

 

http://www.bitzracing.com/products/Partial_EFI_KIT/index.html

[Russ]

I've looked at this too just for driveability, and I have no idea why the intake manifold costs so much, for $3500 you could get something nice made!

[SteamWolf]

Have you considered the other side of the coin... going carb with a set of PMO's ?

 

No.

 

Actually, let me clarify. There's no way I'd remove fuel injection for carbs. It really is a step backwards.

But PMO do sell manifolds with ITB's that would do the trick very well! Full kit is USD$3100 complete

 

http://www.pmocarb.com/products.htm

 

There's a few places around that sell these.

 

http://www.borlainduction.com/ThrottleBody/ThrottleBody-FR.html

USD$2500 but no filters or air horns.

[SteamWolf]

There was an article in the Excellence magazine a while ago about this.

 

I think it was sourced from this crowd, or this maybe the guy.

 

Seems keenly priced:

 

http://www.bitzracing.com/products/Partial_EFI_KIT/index.html

 

His kit is a good one but I wouldn't be using megasquirt. MS was a good option back when an ECU cost over $2k and MS was a $300 kit. Now that it is the same price as a decent ECU there seems to be no point.

 

His injector bungs and rails look the goods tho, if using a stock manifold.

[wasserkuhl]

Yeah I see your point.

 

EFI, if available certainly does offer a far greater power, driveability and economy proposition than Carbs.

 

PMO's are quite expensive as well. But man, the induction noise is just, well, PORN.

 

I reckon you could pick up a C 3.2 Manifold a bit cheaper than the amounts you have said above, just need to go to the world and do a search.

 

Not knowing the answer to this question, but, how about a 964 Manifold?

 

http://www.ebay.com/itm/Porsche-911-964-Carrera-Aluminum-Air-Intake-Manifold-Throttle-Body-/160914145918?pt=Motors_Car_Truck_Parts_Accessories&hash=item25773b027e&vxp=mtr

[Stardust]

Or you could do the 964 plastic manifold. I understand it is a much smoother airflow than the alu one. I believe you need to buy adaptors for the flanges.

[Uncle]

This space held for answers in a minute. Just need to get out of this stupid meeting that has nill to do with me.

[Stardust]

Or the PMO EFI kit

[SteamWolf]

964 manifold adaptors are a bit expensive too, and the rubber joints are not suitable for turbos (which is on my future to-do list).

 

PMO link I posted above
I do like the EFI ITB's and they are high on my want list.

[Uncle]

_{Typed while in stupid meeting..}

 

_{You dont want a 32 tooth reluctor wheel. It will provide crap resolution for tuning and only provide half the input data points that the Haltech will require for anthing more than "Herp Derp turn fuel on now. Stop fuel make go now".You might as well just have a single holley for that kind of tune.}

_{You need to use a 60-2 wheel to provide the ECU with more exact crank referance points. Size is 126mm. A number of people make trigger wheels and crank pulleys as one now or you can just use the same set up I have. DZUG 935 pulley with bolt on wheel.}

 

_{Clewett make a nice neat blank for the dizzy but I would steer clear of the 8mm crank sensor till I have has a chance to play with the 12mm Subaru one I got from Al.}

 

_{In take air temp sensor. I used a Holden LS1 IAT. They work great and you can't kill'em with a stick.}

 

 

_{To make a 964 manifold work you need to spend $1000 on injector block adaptors to make it bolt onto the heads. Your SC motor has 2 stud manifold pattern as you know and the 964 is 3 bolt manifold. The 964 manifold also has a 964 only weirdo not round shape T/B held on with a rubber boot type set up IIRC. Do not want if adding boost. Well just do not want really}

 

 

_{The 3.2ltr Will bolt on needing nothing other than new gaskets. Things to note are the throttle position sensor is really a 3 position switch with a 2nd full throttle switch not a resistor type modern TPS. You have two choises here. You can get BMW TPS and fab up a mount or just get the TPS and mount from Turbokraft. I did the later as it saved me time mucking around looking for just the right TPS.}

 

_{You will need to get one fuel fitting made up for one of the fuel rails the same as I have to get rid of the nasty prone to splitting rubber fuel lines as you can't get the right converter from Earl's,speedflow etc.}

_{The stock injectors are low impedance (7ohm's) and can't be used with a computer like a sprint 500 as the need high impedance injectors. I have a spare set of 36lb high impedance injectors so that's no problems.}

[NaFe]

this is a very interesting read!!! I wonder whether I could ask about the spare injectors you are talking about Martin.

 

I have been doing my own research and there has been several mentions of not oversizing the injectors as this can result in running into problems when tuning for idle...i am sure you are aware, but for those who are not, if the injector is too big, then you can end up the injector opening and closing too quickly.  I wonder what your thoughts are on this...

 

if you follow any of the calculators online, typing in your 203BHP for SC engine and 6 cylinders then they quote around the 21lb/hr mark:

 

http://witchhunter.com/injectorcalc1.php

 

you can lower the fuel pressure when running the larger injectors, but the injectors have a rated flow rate presuming the pressure shouldbe used as a fine tuning exercise?

 

Nath

 

p.s. with the SC Engines running two different manifold diameters 78-80 and 81-83, which i presume match to the head diameter, how does the 3.2L manifolds align???

[Uncle]

You could go with a stock LS1 injector at 24lb that would work. My car will idle all day nice and smooth with 36lb'ers in there no probs. I have some FG XR6T injectors in there right now and it will also idle nice and smooth.

You can go to far though if you don't have the base map to support the injectors. My old XR6T was a good example of this. Lots of bolt on mods bla bla bla with 1000cc injectors. Load the stock map in and it would not idle as it would over fuel. Load 1000cc injector map in and nice and smooth again. It's simply a matter of injector timing. Bigger injector with more CC flow needs to open for a shorter amount of time than a smaller injector with a lower CC flow rate. You can get to a point of not being able to open and shut fast enough to stop over fueling but really You are talking about 60lb injectors on a stock 3ltr type thing.  

This is another point as to why you want a 60-2 wheel. Better control.

 

 

FPR is set at 30psi base before adding pressure under boost.

[SteamWolf]

Uncle,

interesting you say that. I had read that the 64 tooth was problematic and the 32 tooth was ok to use.

 

Nath, I think the pre '75 2.7 was 32mm, post '75 35mm head ports.

78/79 had a 38mm intake runner and all other CIS either side of '78/'79 was 36mm.  I'm led to believe the 3.2L manifold is also 36mm. *edit* seems the base of the 3.2L manifold adaptor is 38mm.

 

Comment on injector sizing sounds about right I think.

[Uncle]

LOL I was yelled at by Heltech et all for even thinking about a 32 tooth wheel for the reasons above.

 

Here is my car on the 2nd start up with injector timing out and very rich. Once the timing was sorted it was smooth as it was with the Webers on there. Injectors here are the 36lb'ers.

 

Click on pic to play.

 

[roodog911]

Guys,

I also have an SC and have been doing some research into EFI. How much of a performance improvement can you expect with a later EFI setup? I thought the cam/piston setup for CIS was pretty mild, so is it worthwhile just replacing the induction system without corresponding changes to the cams?

I am changing the stock exhaust to SSIs and M&K muffler. Next on the list is the induction system, but not sure which way to go yet.

 

Cheers Antony

[KBGr4]

Hi guys, I will have 3.2 fuel system less the computer available shortly for anyone interested. I am still working on putting Jenvy ITB onto my motor

[SteamWolf]

Pm'd!

[SteamWolf]

The advantage of EFI over CIS is reliability and ease of use. No exploding air boxes. No random coughs and splutters.

It also means you can run lumpier cams and other mods the CIS won't tolerate.

[Mike]

_{I have done a few of these the most recent is a 3.2 short stroke. So a 3.0 litre with 98mm cylinders being run with a Wolf V500 although since then the V550 has superseded the V500, this unit gives better control and more features. This engine is running standard 3.2 manifold and injectors, Std cams and heads. It uses a modified distributor as a crank sensor and makes 245 BHP corrected from the wheels. http://www.spyderautomobiles.com.au/files/engine_development.pdf scroll down on the link to the 3.2 short stroke page. This is super drivable makes more power and torque and as a bonus is more economical!}

[SteamWolf]

Thanks Mike that's excellent info.

What are your thoughts on the different brands of ECU available these days? What made you choose the Wolf3D over other options?

[Russ]

nice tags!

 

I gotta buy myself a coupe project car so i'm not tempted to mess with my current car

[Zelrik911]

His kit is a good one but I wouldn't be using megasquirt. MS was a good option back when an ECU cost over $2k and MS was a $300 kit. Now that it is the same price as a decent ECU there seems to be no point.

 

His injector bungs and rails look the goods tho, if using a stock manifold.

Great Topic - I am doing this too!!

 

I have a friend who has a set of Jenvy ITBs on his SC - it is a fantastic improvement over standard &/or carbs - & convinced me to go EFI. But they are from UK and are far too expensive for me.

 

I got wise advice from Uncle (Martin) early on & have started a collection of bits.

I bought a 3.2 manifold from the US, but it wasnt easy. I had to give up on the first one I found on Pelican as the shipping quote to Oz was astronomical. Local (US) people were bugging the seller so he wasnt too interested in helping me with finding alternatives.

 

I will be using M/S and Bitz Kit Fuel tables (to start with) as they are tried & tested. With M/S you dont have to buy the latest & most expensive ECU version, as that has features you will never need on a 911. A new fully assembled MegaSquirt-II ECU is USD 440 from US at the moment (kits are only USD 280). A huge bonus with M/S is the availability of add-on products & software, for example I just bought a  tester unit called a STIM and have Updated & played around with the ECU in my study with a laptop now before I even install bits on the car.

 

I am retired but from an IT background & I think the codeware development that goes into M/S (opensource) has to be better overall than the small specialist firms like Wolf, who were good to start with, but cant possibly keep up with the scale of M/S innovation and improvement. 

 

 

Peter in Melb.

[Mike]

Thanks Mike that's excellent info.

What are your thoughts on the different brands of ECU available these days? What made you choose the Wolf3D over other options?

The Wolf V550 is great value for money, it has all the features and much more for a conversion of a pre '89 911. These include traction control, launch control all the idle control features you would ever need plus more all included in the standard kit, also they are infinitely adjustable in configuration and mapping! At $1895.00 for a universal kit they are great value. Here is a link  http://www.wolfmotorsport.com.au/catalog/category/view/id/95 I am a dealer of theirs which is why the choice was made also they have a life time warrantee and are locally made with great after sales service!