Project Mickey Mouse - Build thread of 79 SC I bought on eBay

[Focker]

Hey Hulley, thanks for the compliments!

The ignition upgrade was pretty straightforward. Instead of using the Clewett distributor hole plug, I used a freeze plug.

Wiring even with the relays wasn't too difficult.

For the carbs, I knew I wasn't sticking with CIS due to cost to refurbish the system and the power limitations.

EFI was a consideration, but it ultimately came down to cost. Although others have had success using more budget friendly ECU such as megasquirt, I didn't want to spend all my time mapping and chasing issues.

Cost no object I would have gone EFI with Link/AEM/Haltech.

I have had experience with carbs on 3 of my last 4 racing motorcycles. The best sounding most enjoyable bike I rode was an SV Superbike with 41mm FCR flat slide carbs.

Nothing, I mean NOTHING sounds like a set of flatslides rattling at idle and screaming on the top end.

[911SauCy]

Originally Posted by Hulley

Please forgive the dumb question,

1. What's the reason for doing a carb conversion as opposed to EFI?
2. How difficult was it to do the ignition upgrade?

I ask because I have a 79' SC also and A) want to do an ignition upgrade (cop) and B) want to do a modern fuel injection or carb conversion myself.

I cannot stand how cluttered the engine bay looks with the CIS, heater blower motor, etc and I believe a better ignition/fuel system would really wake up the motor in terms of response.

Your engine bay looks amazing, really loving this build thread!

Thank you,

IMHO: ITB/EFI conversion is just not worth it.... Plenty of great conversions on here and they sound good and run well, but $20k is just a ridiculous amount of scratch to toss at motor for looks and marginal, marginal, performance increases.

Carbs have the look, they're OG, they sound incredible, power is almost identical to ITBs, for a small percentage of the ITB cost....nevermind the headaches of ITB tuning. You can count on 1 hand how many people in this country can proficiently tune EFI/ITBs, Al Kosmal on here is one of these wizards

That said, a properly tuned/cared after CIS works flawlessly and makes fantastic power as well. Mine makes as much and in some cases more than comparable ITB set-ups I've seen.

In coming off the soap box...ITB's are literally just Carbs with fuel being squirted into them instead of sucked in, they are not rocket appliances but they certainly cost like one

[Showdown]

The one truism within the Porsche fuel management debate is that everyone is firmly rooted in whatever system they have on their car:

CIS folk think it’s the most reliable and predictable.

MFI camp swears by the analog mechanical directness.

Carb club professes the realest, rawest system.

EFI/ITB gang is all about the best of all worlds.

Each has its pros and cons. There’s no perfect system and one must first define their own wants/needs ambitions/limits.

[Focker]

Originally Posted by Showdown

The one truism within the Porsche fuel management debate is that everyone is firmly rooted in whatever system they have on their car:

CIS folk think it’s the most reliable and predictable.

MFI camp swears by the analog mechanical directness.

Carb club professes the realest, rawest system.

EFI/ITB gang is all about the best of all worlds.

Each has its pros and cons. There’s no perfect system and one must first define their own wants/needs ambitions/limits.

This.

A well setup and tuned efi is miles ahead of carbs in terms of fuel economy and drive ability throttle etc., but it costs a lot of $$$ to get the drivability and part throttle mapping etc.

MFI is like direct injection from 40 years ago.


Money no object, I'm going MFI followed by EFI then carbs. But, for $4500, a turnkey 46mm carb solution gets you pretty close for a lot less money

[Hulley]

Originally Posted by Focker

Hey Hulley, thanks for the compliments!

The ignition upgrade was pretty straightforward. Instead of using the Clewett distributor hole plug, I used a freeze plug.

Wiring even with the relays wasn't too difficult.

For the carbs, I knew I wasn't sticking with CIS due to cost to refurbish the system and the power limitations.

EFI was a consideration, but it ultimately came down to cost. Although others have had success using more budget friendly ECU such as megasquirt, I didn't want to spend all my time mapping and chasing issues.

Cost no object I would have gone EFI with Link/AEM/Haltech.

I have had experience with carbs on 3 of my last 4 racing motorcycles. The best sounding most enjoyable bike I rode was an SV Superbike with 41mm FCR flat slide carbs.

Nothing, I mean NOTHING sounds like a set of flatslides rattling at idle and screaming on the top end.

Thank you, precisely why I really like the PMO carb option, the idea of constantly messing with tuning doesn't sound like fun and coming from a dirtbike background, I'm very comfortable with carbs and the simplicity is awesome.

[RDM]

Originally Posted by Focker

But, for $4500, a turnkey 46mm carb solution gets you pretty close for a lot less money

Best guess- what's a turnkey MFI system cost?

[75 911s]

Originally Posted by RDM

Best guess- what's a turnkey MFI system cost?

Pump is 2-3k for a core, then 1k to rebuild. Plus 1k for a custom RSR space cam.

You need MFI cams, pulleys and a belt. and MFI engine tin. You need MFI heat exchangers or to mod the MFI pump with a manual enrichment (1k +) you also need MFI engine tin for the back of the motor.

Plastic or hardlines.

Heads that have MFI ports or can be drilled to ports, or aftermarket adapters.

Throttle body cores are about 1k depending on condition.

Plastic stacks you can get for 800 or so if you are going for the stock look.

Air cleaner another 900 ish.

You need a MFI fuel console and filter 1k ish.

Other more custom or race inspired intake would be much more. (For instance high butterfly or slide valve)

You'll need to change or recurve the dizzy at $600-800

I know Johnny built a test rig to test his and who knows what that cost, alternative is ....trailering to 1 of 3 places in the world that can tune it for you? Who knows who is competent to tune a custom MFI setup.

Carbs really are the cheapest, best bang for the buck imho. For those who know what they are looking at, wow factor on MFI is unbeatable.

[911SauCy]

Originally Posted by Showdown

The one truism within the Porsche fuel management debate is that everyone is firmly rooted in whatever system they have on their car:

CIS folk think it’s the most reliable and predictable.

MFI camp swears by the analog mechanical directness.

Carb club professes the realest, rawest system.

EFI/ITB gang is all about the best of all worlds.

Each has its pros and cons. There’s no perfect system and one must first define their own wants/needs ambitions/limits.

As a lover of my CIS, If I had the choice of any of these options, MFI would be the go to, carbs, then efi/itb....the juice isn't worth the squeeze with efi/itb

Regardless...we're digressing.

UPDATES, Focker!?

[Focker]

Not a ton to report at the moment, but I'm about to embark on a bit of upholstery.

I'm going to be covering the dash in leather so I can get that back in and have the glass guy reinstall the front and rear wind screens.

My dash is in excellent condition, but I wanted it to be in leather along with the top of the door caps.

Fuel system should be good to go this weekend.

[Coastr]

Surely only masochists and vintage racers (birm) would attempt a new MFI install?

Carbs for the show, Efi for the go. There’s a lot of cars getting about with them now, can’t be that hard to tune. But they are cheaper as already noted.

[Focker]

Very brief superbowl Sunday update.

I hate the following things:

WIRING
CONTACT CEMENT THAT CLUMPS UP
F*CKING BUTYL TAPE
WIRING
REROUTING FUEL LINES
PANEL ALIGNMENT
WIRING
UPGRADES THAT TURN OUT TO BE A PAIN IN THE ASS AND MAKE YOU QUESTION ALL LIFES DECISIONS
WIRING


Thank you.

Go Bengals.

[chrisbalich]

I'm with you on the hatred of wiring.
I've read multiple times how it's very Zen, but I find it quite stressful.

[Jonny042]

Originally Posted by RDM

Best guess- what's a turnkey MFI system cost?

Pretty much priceless. Since IMO there is no such thing.

Duane is pretty much on the money with his reply. I built my entire engine and project car around the MFI system once I got hooked on Maniacal Fuel Injection..... and it was worth every penny and then some. But it's not something you can bolt on and go it has to be a planned effort right out of the gate.

PMO carbs are basically the best option for simplicity, functionality, and lack of wiring. Aftermarket EFI and ITB's for that last 5% power and tunability.

[AutoXer23]

Nice build.. Mine is actually being painted the same color

[Focker]

Brief update.

I finished plumbing the fuel system and it turns out my *****ty job welding on the AN6 fitting to the return line on the tank so I had a small fuel leak. I think I got that sorted out now.

Glass guy comes on Monday to install front and rear windscreen. Slow progress now as I am in my busiest part of the year for work.

[Hulley]

Originally Posted by Focker

Brief update.

I finished plumbing the fuel system and it turns out my *****ty job welding on the AN6 fitting to the return line on the tank so I had a small fuel leak. I think I got that sorted out now.

Glass guy comes on Monday to install front and rear windscreen. Slow progress now as I am in my busiest part of the year for work.

Pics for God's sake, we need em!

[Focker]

Originally Posted by Hulley

Pics for God's sake, we need em!

I will post some pictures over the weekend.

I did try a test fire on the engine but it just coughed and acted up. In all my excitement to put the engine together, I didn't disassemble and clean the carbs that I got second hand and they were a bit blocked up.

Rebuild kit is enroute from Parts Klassik after I tore one of the paper gaskets, but otherwise they are clean and ready to rock and roll.

It WILL be driven by April 30, 2022 (its 3 year anniversary).

[Focker]

Tidied up the garage and dropped the car back on its own feet.

Pictures as promised.

[chrisbalich]

Looking great!

Ready to see it rolled out into the sun!

[proporsche]

just today i thought to myself pastel grey will look great on 911 and here we have it..looks superb

Ivan