Porsche 944+Chevy V8

Post by **Hambden Bob** » Sat. Aug. 03, 2024 9:26 am

Stokes',You're Truly An Animal..!! Eh,Maybe A "Bloodhound"!! Once You're "On Da' Case",You Don't Stop Until It's Solved..!!

I'm truly impressed with Your results on the drive..!! Sidenote- It seems these days that Fuel Pump and Fuel Regulation Equipment has become "Iffy" in the lower, more reasonably priced group. Being that as it may, You just can't dance with pressurized Fuel hazard chances. Thanx for the companion videos that You include in Your posts..!! Most helpful. Smitty oughta get thoroughly turned-on by this one..!!

Post by **StokerDon** » Sat. Aug. 03, 2024 10:09 am

Hambden Bob wrote: ↑Sat. Aug. 03, 2024 9:26 am Smitty oughta get thoroughly turned-on by this one..!!

Thanks Bob! There hasn't been a Smitty sighting yet today, but the day is young!

The pictures and videos again.

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Post by **StokerDon** » Sun. Aug. 04, 2024 9:36 am

I am love'in the carb conversion!

Here is the video.

We are heading in the right direction now. Hard to believe I drove it with terrible throttle response for 4 years. My original plan was to sort out the car while running the carb, then wire up the factory EFI. I guess I should have stuck to the plan!

-Don

Post by **StokerDon** » Fri. Aug. 09, 2024 9:04 am

Just about done with the carb conversion!

Scuffed and painted the hood scoop. I used Rust O Lium Semi Gloss Hi Heat black, same stuff I use on boilers and stoves.

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Next, we did some trimming of the hood hole to center the air filter in the hole.

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We also installed some rubber door trim from the hardware store around the hole. This will encourage rain water entering the scoop to go around the hole rather than dumping on top of the engine.

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Then the moment of truth...
Installed the Aeromotive 13220 regulator.

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IT WORKS!!!
I was able to set the high side pressure at 12 PSI. And the low side to 5 PSI.

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I now have a HAPPY CARBORETOR!!!

The video will be out at about 6:00 today.
-Don

Post by **StokerDon** » Sat. Aug. 10, 2024 8:23 am

The carb install is DONE!

The hood scoop is painted and mounted!

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I guess it don't suck too bad...

Now we move on to tuning.
Got the MSD View software loaded onto my old laptop. We're set at 32 degrees coming in by 2400 RPM. Also have the internal MAP sensor connected to manifold vacuum.

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The carb seems a little fat so we'll play with rods, springs and jets today.

-Don

Post by **StokerDon** » Sun. Aug. 11, 2024 7:59 pm

I've been able to keep up on the videos, but fall'in behind on the type'in!

The MSD setup seems good. On the carb, we stepped down 2 sizes in main jet and bumped the accelerator pump up to the middle adjustment hole. It runs Great!

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This morning we played with the alignment. I wanted to try more castor angle. I didn't have time to do proper castor measurements so I very crudely cranked in a quarter turn. Set the camber to -1.5 degrees and toe to 0.0".

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These settings noticeably improved turn in and make the steering a little lighter feeling. All good things!

-Don

Post by **StokerDon** » Sat. Aug. 17, 2024 6:27 pm

We've got the carb pretty well sorted out. Here are our current settings.
Main Jet = .101
Accelerator Pump = #2 Hole
Metering rod = .065" x .052"
Pink Spring

Got 15.75 miles per gallon on the first tank full. I'm hoping to get a little better on the second tank now that we are about done tuning.

We also made some interesting revelations about Cowl Induction. It actually works, we tested it!

-Don

Post by **Hambden Bob** » Sun. Aug. 18, 2024 10:16 am

Holy Cats Stokes..!! Nice Technicals..!! Looks like "Miss Porche" is operating in "Happy Land"..!!

Post by **StokerDon** » Sun. Aug. 18, 2024 8:03 pm

Hambden Bob wrote: ↑Sun. Aug. 18, 2024 10:16 am Holy Cats Stokes..!! Nice Technicals..!! Looks like "Miss Porche" is operating in "Happy Land"..!!

You'll also be happy to know we got 17.25 MPG on the second tank of gas. We can probably do even better now that we have zeroed in on the right settings, and we can keep our foot out of the gas.

We tuned on that fuel injection for 4 years. It only took a week to tune the carb, and it runs better now than ever.

Pretty interesting.

-Don

Post by **StokerDon** » Sun. Aug. 25, 2024 6:26 pm

Not much to report this week. Only got 15.01 MPG on the last tank. But, we got loads of Smiles per Mile!

Minor tweaks this week, accelerator pump set to high, radiator fan switch replaced, Toe adjustments. It runs and turns better than it ever did before!

Let's Make Some Noise!!!

Post by **Rob R.** » Sun. Aug. 25, 2024 6:57 pm

Hey Don - about the cold morning stumble - do you have the choke setup? Are you sure you don’t have the idle mixture overly lean?

Post by **StokerDon** » Fri. Aug. 30, 2024 9:40 am

Rob R. wrote: ↑Sun. Aug. 25, 2024 6:57 pm Hey Don - about the cold morning stumble - do you have the choke setup? Are you sure you don’t have the idle mixture overly lean?

These are good points Rob, thanks!
But, I probably should have said that it is a cold running condition stumble. Cold starting is no problem so it is not a choke issue. I didn't get much time to play with it because mornings were in the mid 50's for only 4 days. Driving home in the afternoon when it was in the 80's was no problem. Also, I adjusted the accelerator pump and idle mixture when I got home on the first day and there were no problems after that.

I think we may have to revisit this in another month when temps go down a bit. For reference, the choke is not used in this application and is mechanically set to full open. The intake manifold has no prevision for plenum heat or carb heat so cold temps might be a challenge.

For now, it still runs great!

Post by **Rob R.** » Sun. Sep. 01, 2024 8:55 am

It sounds like you are on the right track. Back when I was drag racing I replaced a dual-plane intake with a big single plane. Installed the same Holley carburetor, backed it out on the road and floored it....and it stalled! I drove myself crazy getting the accelerator pump circuit dialed in. Eventually I replaced the 30cc pump on the secondary's with a 50cc pump and a big nozzle, that did the trick! I think I still have a box full of pump cams and nozzles out in the shop somewhere.

A lot of people like the Edelbrock carburetors because most of the time they run pretty good out of the box and are relatively simple to tune. By changing the pump linkage you have increased the amount of fuel delivered in each "shot" from the accelerator pump, but if that turns out to still not be enough you can experiment with different nozzles. A larger nozzle gives you the same volume of fuel, but in a shorter amount of time.

https://www.summitracing.com/parts/edl-1475

Post by **grumpy** » Sun. Sep. 01, 2024 9:12 pm

Did you notice more power?

Post by **StokerDon** » Sun. Sep. 01, 2024 9:52 pm

grumpy wrote: ↑Sun. Sep. 01, 2024 9:12 pm Did you notice more power?

Using my 'Butt Dyno', maybe a little.

I would have to get 4th gear wound out to really be able to notice. That would be way over 100 MPH though. Best I can manage on my roads is about 90.

Rob R. wrote: ↑Sun. Sep. 01, 2024 8:55 am Back when I was drag racing I replaced a dual-plane intake with a big single plane. Installed the same Holley carburetor, backed it out on the road and floored it....and it stalled! I drove myself crazy getting the accelerator pump circuit dialed in.

That right there is what I was fighting on this fuel injection system. If you opened the throttle too much at low RPM, it would try to stall. I've had builds that acted that way but revved super hard above 3000 RPM. But this is a 6.0 Liter V8 in a light-ish car. With the FI it should putt putt around at close to idle but it would not.

I never ran one of these carbs before. I've always had Webbers, SU's, Holleys and Qadra-jets. I was real surprised how this ran right out of the box. Tuning wise, after changing a bunch of things, we ended up one main jet size smaller and one step stiffer on the spring. Everything else is back to as it came out of the box.

If it was a race car, I would have put a 750 double pumper on it. Since it is mostly a street car that gets driven to work I need something a little more flexible. This 800 CFM AVS2 really works great and I would rate it better than a modified Q-Jet any day.

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Did some toe adjustments and the front end is as perfect as I can get it with primitive tools. To get the rear to help with turn in, I bumped the rear sway bar up one notch stiffer.

So here is a video of me driving around in circles and around country twistiness to test it out.