AO

I'm not sure you can do it, but you might consider trying S4 fuel rails. There's a variety of injector sizes that will work with those, e.g. 24, 30, 42.

Edit: D'oh! Nevermind! I didn't consider the electrical connections.

hacker-pschorr

The stock injectors are 24lbs - more than enough for 14psi on these cars. Tim Murphy has pushed the stock S4 19lb injectors to over 10psi with no issues.

Is it ideal? No, but how much boost are you shooting for? If under 10psi, start small & get that to work. I'm running just fine with the stock injectors with 6+ pounts of boost. I say 6+ because on a cold 40 degree morning like today, it's making more power than the 6.1 pounds of boost I saw on the dyno in July. Air / Fuel is still perfect.

Everyone is always in such a hurry to swap out injectors. Fueling the car under boost is the easy part (at lest with a centrifugal it is). The hard part is day to day driveability.

If you are running an aftermarket ECU - then yes, everything I just said is out the window.

Tony

IF..IF...you really jack up the Fuel pressure. Sure...and the level it will take, i would DEFINTITLY check the hoses on an older 16 V car and make sure you have a pump to push it..

Or...

Use a Sharktuner and then have a pump adequete to flow that much fuel at/near 90-100% duty at the lower pressure.

On an 16v car, i dont think any of those are an opiton yet?

With the prices and "simplicity" of 16v cars, id love to see some good HP numbers added to them!

AO

Agreed! Sure would be cool to get a nice setup for say, less than $10k, that would spank some butt!

Fabio421

How does over 400 rwhp and 450 lb/ft of torque sound on a 4.7l sound? And yes, there is a dyno chart available. It is a car here in FL. You actually know the car and the builder.

hacker-pschorr

Bingo!
Like I said, maybe not 100% ideal, but it works.
I agree 100% - also, anyone making any type of performance gains should be checking / replacing 20 year old hoses anyway.
[QUOTE=Tony]Use a Sharktuner and then have a pump adequete to flow that much fuel at/near 90-100% duty at the lower pressure.

On an 16v car, i dont think any of those are an opiton yet? [QUOTE=Tony]
No Sharktuner for the L-Jet. Even the 951 updates do not work on the 928 due to different voltages in the systems.
I’m already around 340bhp with my 81 with low boost and the original 4.5 liter.
$10k? Hell, for an OB that can include the car!!!
Share the details – not sure how I missed this car if it was posted here in the last 5 years. Sounds cool.

Jean-Louis posted around 380rwhp with a 10.4:1 Euro with low boost & no intercooler. This setup survived 2-3 track weekends with two drivers. Anyone who knows JL is aware he does not ***** foot around Road America.

Hell, if I cranked up the timing I could rip off one impressive dyno chart. I would never dare drive it that way …..ok, maybe I would. JL’s car is the best example of what you can do with a 16V motor.

AO

That's what I meant!

ceedee

haha, i know the builder. but i am not telling...

John V

I'd like to know more about this one myself. You wet our appetites, you can't clam up now. Do tell!

hacker-pschorr

If it's who I think it might be - the car isn't L-Jet anymore & has had other modifications. Not hat it matters, just worth mentioning.

Hell, there's a 2.2 liter in Green Bay putting 722 down to the wheels Anything is possible with the right parts.

ceedee

true hacker,
anything is possible with the right parts, the ***** to do it and the brain to get/keep it operable.

a4sfed928

[QUOTE=Tony]IF..IF...you really jack up the Fuel pressure. Sure...and the level it will take, i would DEFINTITLY check the hoses on an older 16 V car and make sure you have a pump to push it..

I am tring to avoid this with the proper sized injectors since mine need replaced anyway. I think I'm getting close to a solution now.

hacker-pschorr

I agree this is the correct approach. Problem is, the L-Jet computer is set for 24lb injectors. So when under vacuum (95% of your driving) too much fuel will be entering the cylinders. Like I said, tuning for boost is easy, the daily driving part is the PIA. If this were a track car it wouldn't matter. Dumping that much fuel as you putter along the highway at 65mph is going to foul your plugs and kill the O2 sensor.

Speaking from experience here, just trying to help. If you found a way to dial fuel back under vacuum for non-boost driving. Awesome!!!! Please share!!!

Fabio421

I'm not able to post the builder, there is a gag order in place. Lets just call the builder Schmoopie. Hacker is on the right track. I believe the car is still running the L-Jet however it has been modified to use a MAF instead of an AFM to increase throttle response and allow for laptop tuning. Its actually an affordable route to take to get a tuneable fuel system in an OB.

hacker-pschorr

Then it's running MAF and not L-Jet......

I've thought about doing this. Maybe in the future I'll drop the L-jet system or switch to an adapted system like this.

I'll be switching my 79 CIS to either the EuroS EFI system or an aftermarket setup such as autronic before I add any boost.