EFI upgrade of k-jetronic on GTSi

One other item you will likely need to fab is the throttle body extender to add room for the injectors/fuel rail. You can see this in some of the photos above.

 

The reason for the extended TB is to make room for the injection rail. At least that’s the route I had to use. It will be interesting to see if the TB you linked to can eliminate that interference. Please keep us posted.

 

No TB extender on the setups I've done....a little notch on the top of the rail, a little rework on the TB idle screw and it fits.

 

Mike,
Did you use full size injectors?

 

No, the little pico type. I set the lower oring like right at the port edge so as low as possible, and the otop oring like almost breaking into the bore of the rail....and it fits. I think I've done 1/2 dozen over the years and everyone's seemed happy, one guy order a 2nd.

 

I’m looking for the $1 dollar per 1 horsepower formula, anyone have that handy?

 

Honda swap?

 

To the question of why though, drivability then versatility. Carbs are kind of cool but they are never quite right. CIS usually runs well but you can't ANYTHING and keep it running right. EFI just works...same mixture everyday regardless of weather or elevation, it doesn't much care what camshafts you pick out or how much boost you add...its just nice, not original, but nice.

 

You can just add pins to your flywheel and use the stock sensor. About 6 pins evenly spaced will work.

 

people do it. You just need to be sure you pick a sensor small enough to work this the tooth size. Also remember that the cam is turning 1/2 speed of the crank so if you buy a 36-1 wheel and the controller accepts a cam only trigger, great, but if its expecting a crank trigger you'll need to remove another tooth and call it an 18-1 in the setup.

 

I'm going to look like a completely ignorant knob (English term ) with this question (because basically I am ), but...... What is the gain with all this work?

By that I mean, it seems like an awful lot of effort to go to, so I assume there must be some big gains to be made (power/torque/driveability/all three?)

I was of the understanding that, as "basic a system" as it is, the Bosch K-jetronic is a pretty reliable system, that even after 30~40 years service, doesn't require a lot of maintenance to keep it running (if any maintenance at all)

By adding a more modern injection system, you're adding aftermarket control systems and sensors that can introduce reliability issue.

The 308/328 series is an old car now - An F355 would hand it's arse to it, let alone something like a ferrari 296 (I was out and about last night in my 328 GTS, driving on a twisty main road at @ 80~90 mph, and I was absolutely urinated on by a Porsche 911 GT3 who passed me like I was parked at the side of the road!) , so what makes all this work and effort worth doing?

 

on a QV it gains you about 20hp. The CIS is quite restrictive is 2 ways. 1 is air flow and that is where the 20hp comes from, 2 is cam timing so once the CIS is gone you can run any cams or turbo or blower you please and that a a good number of 300=800hp 308s out there..classic looks with modern hp.

800hp in a 308 is hard to handle BTW...this is 1/2 throttle and not quite 2/3 redline

 

We found the best cleaner was CRC Mass Air Flow sensor spray cleaner.
Very strong and our new 328 runs much better

 

I would say look at the charge time to be sure you are getting a full charge at redline.

High voltage means its more prone to arcing were you didn't mean....so better wires, lose the extenders (I had horrible luck with them burning through) and the cap and rotor will not last as long.

Coil resistance is more a points thing....it does change the current flow so make sure you have adequate size wiring or you won't get the volts it claims to deliver.

 

Yes, 2 coils helps charging time but it's still something you should confirm.

Coil resistance sets how much current will be flowing though the coil after its fully charged, so it set how much heat is generated if you dwell time is longer than needed. You will need to set the dwell time in the ECU.

Coil charge (dwell) time it a combination of resistance and inductance with the inductance being the primary factor

I'm not aware of any restrictions on coils here in the US.....I guess it could fall under the general don't mess with anything rules in CA, not sure.

 

I recommend to install a crank sensor on the harmonic damper and a cam sensor directly on one of the intake cams. That way you have easy access and full flexibility for adjustment and tuning of you efi setup. I've used mostly modified standard equipment for both crank and cam sensor setup.

Best, Peter

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