Weber 44 IDF's - keep - or find original d-jet? Options

[Gatornapper]

Questions re: Weber 44 IDF carbs:

1. Is anyone running these on a stock engine, and if so, how do they perform? National Carburetors kit for stock engines is 34 ICT's, lightly modified 40 IDF's, and only 44's on heavily modified engines.

2. What problems do you introduce using 44's? other than dumping too much fuel in the engine......

3. Venturi's are 45mm, someone pointed out that one should use 40mm venturi's - is that with a stock engine?

4. Anyone run 44's and then convert back to EFI? How did that go? Labor cost?

TIA,

GN

[BillC]

It'll be more work than just slapping on a set of carbs, but I think you'll be happier in the long run if you install the original D-Jet setup. Plus, the car will be worth more once it's all done.

If you're going to stick with carbs, the 44s are too big for a stock engine. The 40s might work for a 2.0, but might be too big if you still have the stock cam. The 34s will give you the best drivability around town and fuel mileage, but you might sacrifice a little on the top end on a 2.0.

[Gatornapper]

Bill -

I restore old motorcycles so I know the more original, the more the value....

The 44's are on the car now & I'm rebuilding them. My good friend in whose barn the car has sit for 10 years said the car was running perfectly when it was driven in the barn and he had been riding in it with the PO (another friend of his) that day.

I'm now thinking I want to flip the car ASAP.

Will the car run ok with the 44's? 10mpg?

And where would I start looking for the original D-Jet setup and how do I know I'm getting a full, properly working system? Reliable sources?

Thanks!

GN

It'll be more work than just slapping on a set of carbs, but I think you'll be happier in the long run if you install the original D-Jet setup. Plus, the car will be worth more once it's all done.

If you're going to stick with carbs, the 44s are too big for a stock engine. The 40s might work for a 2.0, but might be too big if you still have the stock cam. The 34s will give you the best drivability around town and fuel mileage, but you might sacrifice a little on the top end on a 2.0.

[Gatornapper]

The PO told me the Weber's didn't produce any more power, but made the engine a lot more responsive......

GN

[Gatornapper]

Don't you have to pull the engine to change the intake manifold?

Or can it be done from on top? Doesn't seem possible from looking at things.....

GN

[Gatornapper]

A long-term member here has a complete D-Jet system in his garage for $250 - think I'd better grab it.........

GN

[thelogo]

Yeh the 44s are technically too big but

D-jet is not supported by me personally cause it is waaayyyy
To complex or spookey weird

Carbs are simple , me i just trust them alot more

But they constantly want to go wide open throttle



(IMG:style_emoticons/default/sheeplove.gif) D-jet never gos wide open throttle (IMG:style_emoticons/default/screwy.gif)




Where is the go to 914 world , individual throttle body
Fuel injection conversion , that i would buy .
But carbs till then

[Gatornapper]

????? So why won't the D-Jet go full throttle?????

GN

Yeh the 44s are technically too big but

D-jet is not supported by me personally cause it is waaayyyy
To complex or spookey weird

Carbs are simple , me i just trust them alot more

But they constantly want to go wide open throttle



(IMG:style_emoticons/default/sheeplove.gif) D-jet never gos wide open throttle (IMG:style_emoticons/default/screwy.gif)




Where is the go to 914 world , individual throttle body
Fuel injection conversion , that i would buy .
But carbs till then

[Gatornapper]

Logo -

Options:

1. So, If I put a cam in the engine and high-performance exhaust on, the 44's would work?

What would that do to the value of the car? Money in, value down it seems.

2. Buy the kit for the 34 carbs, easy install, sell the 44's (they'll be looking like new after my rebuild) for the cost of the 34's. Simple, easy, little to no cost - engine should run great.

3. Buy the D-Jet system from an "original" member here ('04), go through the hassle of learning the system (experienced with old Volvo EFI systems), finding & replacing possible defective parts, sell the 44's for a profit.

Decisions, decisions, decisions. #2 is the most simple for me.

On #3, how to I ensure that the D-Jet system I purchase is good? Lots of parts could be defective, including the difficult-to-find ECU.

GN





[quote name='thelogo' post='2536095' date='Oct 9 2017, 10:27 PM']
Yeh the 44s are technically too big but

D-jet is not supported by me personally cause it is waaayyyy
To complex or spookey weird

Carbs are simple , me i just trust them alot more

But they constantly want to go wide open throttle



(IMG:style_emoticons/default/sheeplove.gif) D-jet never gos wide open throttle (IMG:style_emoticons/default/screwy.gif)




Where is the go to 914 world , individual throttle body
Fuel injection conversion , that i would buy .
But carbs till then
[/quote]
[/quote]

[BeatNavy]

If you don't want to learn D-Jet, do what you know. There will be a learning curve, and yes, the D-Jet components will be in varying states of usability and repair. I'd recommend buying a new wiring harness from Bowlsby if you do go that route, but that's just my thought.

Part of my personal enjoyment with these cars is challenging myself and learning new things, but that's not an interest for everyone. Some people just want it to work and drive it.

Your car, your call.

[TheCabinetmaker]

D jet won't go full throttle? (IMG:style_emoticons/default/confused24.gif) (IMG:style_emoticons/default/av-943.gif)

[BeatNavy]

D jet won't go full throttle? (IMG:style_emoticons/default/confused24.gif) (IMG:style_emoticons/default/av-943.gif)

Yeah, I didn't understand that either (IMG:style_emoticons/default/confused24.gif)

[TheCabinetmaker]

Just


Another



Useless



Post?

[Gatornapper]

BN -

Normally I LOVE mechanical/electrical challenges, and all things being normal, I'd really enjoy doing this.

But right now I am (at 72) totally overloaded with technical challenges flipping a fairly expensive house with a lot of issues and fighting a dozen other alligators (someone ask me where "Gatornapper" came from sometime - name given to me by a major US newspaper.....in 1965), and the last thing I need is another challenge.

I only bought this car because of all the work IT DIDN'T NEED, but have worked on enough old vehicles (I restore old motorcycles) to know there would be plenty of hidden issues to deal with. I just don't need to add more......

So how much is a new wiring harness?

I know it's inevitable that "components will be in varying states of usability and repair." - and some parts are getting very hard to find.

I think I have a plan - will post it next.

Thanks man!

GN

If you don't want to learn D-Jet, do what you know. There will be a learning curve, and yes, the D-Jet components will be in varying states of usability and repair. I'd recommend buying a new wiring harness from Bowlsby if you do go that route, but that's just my thought.

Part of my personal enjoyment with these cars is challenging myself and learning new things, but that's not an interest for everyone. Some people just want it to work and drive it.

Your car, your call.

[Gatornapper]

Ok, here's the plan:

1. Purchase D-Jet unit (complete) from bigkensteele;

2. Finish rebuilding existing Weber 44's, see how car runs. If I can tune carbs where car runs well (or find a tuner who can), get car in top mechanical and beauty shape and sell it & the D-Jet system with it; a strong position.

NOTE: Local Porsche dealer service manager remembered every detail about this car and the carbs being put on. Said it was running perfectly when service was finished installing the carbs & there were no issues then.

3. If Weber 44's cannot be tuned so car runs well, I will pull them and install the D-Jet system. Invariably there will be issues, problems to solve. Big Ken said car was not running well when he pulled the system from his '76 2.0. If I can get car running well with D-Jet installed, I'll sell it that way and come out ahead - I'll sell the Weber 44's for a good price as I'll have them like new & they only have 2,000 miles on them. An even stronger position.

4. If a good Porsche mechanic cannot get the D-Jet system running well, I'll purchase and install the Weber 34 ICT kit, get car running well (should be very easy), and sell car WITH the D-Jet kit so new owner can install it if he/she wants to. I'll sell the almost-new, rebuilt Weber 44's for a good price. Not a bad fall-back position.

Hey, TEAM!......

Sound like a plan?

GN

PS: Wife (wonderful, beautiful) normally lets me do what I want vehicle-wise. But she has strongly communicated she wants only one Porsche in the family.

[TheCabinetmaker]

So, you bought a 914 to flip and make money? I wish you luck sir.

[Dave_Darling]

If the cam has been changed out for a carb-friendly one, you'll never get the D-jet to work right.

Sir Andy got his car to work OK with 44s, but he swapped in smaller venturis. I don't remember the size, possibly 36es?

The larger carbs on the smaller engine will give you a week vacuum to pull fuel into the air stream. Mixture quality will suffer at low RPMs, and low-end torque and drivability will probably be worse. It will be able to wind way up at WOT, but the stock cam and heads limit your useable RPM range anyway.

That said, they can be made to work. But 40s are generally preferred on 914 motors.

As Rob C. said--if you know carbs and don't want to learn D-jet, stick with carbs. Use your best judgement on what size will work for you.

If you're selling the car, it's usually best to do as little as possible to it. You almost never get back the full cost of work done to a car when you sell it.

--DD

[Gatornapper]

Actually I bought it to keep it. And to enjoy driving it.

Very recent changes in our financial situation dictate that we need the cash.

Ever had that happen? If not, you are young.......

GN

So, you bought a 914 to flip and make money? I wish you luck sir.

[TheCabinetmaker]

Hmmm, my profile says I was born in 1948, so I guess I'm not very young

[Gatornapper]

ALL NEW INFO!

My expert friend in GA advised me to call Pierce Manifolds in CA as they are one of the top Weber carb experts in the nation. Had a great long talk with Steve who blew me away with his knowledge of Weber setups with the 2.0 engine.

Findings:

1. The existing setup with the 44's with 44mm venturi's would work fine on the stock 2.0 engine, producing this performance: no low-end torque, great performance between 4500 and 6500 rpm. I.e., racing. As the PO used to race 911's, he probably DID know what he was doing and wanted to get the best performance out of the stock 2.0 engine, while sacrificing all low-end/street-drivability performance. Low-end and mid-range torque would both be weak.

2. The 44 IDF carbs would perform perfectly fine for regular street driving, up to 5000 rpm, using 32mm venturi's, providing good mid-range torque.

3. I had him run his calculations (was he using a calculator? Sounded like it! Certainly wasn't a computer as he was doing square roots, etc.!) for 34mm, 36mm, and 40mm venturi's. For each one he would give me the torque levels at various rpm.

4. All venturi's larger than 32mm suffered a loss of mid-range torque, with the gain of high rpm torque. After listening to all the numbers he ran by me, it was clear that even the 34mm venturi's would require almost constant driving above 4500 rpm - which is not - to me - normal driving. Not on a 41 year old Volkswagen engine with 60k miles on it.

So I ordered a set of 32mm carbs and cannot wait to see how they run. If all is as I expect it will go, I'll leave the 44's on the car and let the next owner decide on the D-Jet system.

If I feel the higher rpm performance is lacking, I can easily try 34mm venturi's - for just $60.......

GN