Fuel injection to Carbs? |
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Fuel injection to Carbs? |
torakki |
Jun 27 2024, 11:32 AM
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#1
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Member Group: Members Posts: 51 Joined: 5-October 18 From: Nor Cal Member No.: 22,545 Region Association: Northern California |
In the process of swapping the FI, on my 2.0L to Empi carbs. My research never found anything about the dizzy needing to be changed. Now I see in the Empi instructions, to swap the distributor. It sounds like, just for timing advance. I wasn't planning on the extra expense so is this necessary?
Thanks |
emerygt350 |
Jun 27 2024, 11:35 AM
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#2
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Advanced Member Group: Members Posts: 2,403 Joined: 20-July 21 From: Upstate, NY Member No.: 25,740 Region Association: North East States |
If you haven't changed the cam, I don't see why you would change distributors if you are trying to save money.
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NARP74 |
Jun 27 2024, 11:45 AM
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#3
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Senior Member Group: Members Posts: 1,172 Joined: 29-July 20 From: Colorado, USA, Earth Member No.: 24,549 Region Association: Rocky Mountains |
Now you did it...
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Superhawk996 |
Jun 27 2024, 11:50 AM
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#4
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914 Guru Group: Members Posts: 6,469 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch |
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GregAmy |
Jun 27 2024, 12:06 PM
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#5
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Advanced Member Group: Members Posts: 2,370 Joined: 22-February 13 From: Middletown CT Member No.: 15,565 Region Association: North East States |
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rhodyguy |
Jun 27 2024, 12:47 PM
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#6
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Chimp Sanctuary NW. Check it out. Group: Members Posts: 22,188 Joined: 2-March 03 From: Orion's Bell. The BELL! Member No.: 378 Region Association: Galt's Gulch |
Don’t forget to purchase a new low (correct pressure) pressure fuel pump. If you are new to dual carbs be patient and remain calm.
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Superhawk996 |
Jun 27 2024, 01:24 PM
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#7
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914 Guru Group: Members Posts: 6,469 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch |
So no one else dares wade in and answer your question. (IMG:style_emoticons/default/happy11.gif)
I’ll stick my neck out. Problem is with carbs you pretty much lose the ability to use vacuum advance or vacuum retard. Yes, there are cobble solutions. Trust me that you don’t want to know about them right now. So what you need is a distributor that can give you the advance the engine wants without vacuum. That means a dizzy swap. 123 is great but crazy pricey. There are other options all the way down to the Bosch 009 centrifugal advance which was the “ticket” back in 80s but really is sub-optimal without having it re-curved (again you really don’t want to know). So can you survive without swapping? Yea. But performance will suck and you will have unsolvable flat spots that will seem like carb tuning issues but it really is an ignition problem. Nuisances - yes. Catastrophic - no as long as you keep your total advance reasonable around 27 degrees BTDC. Are we having fun yet? Unfortunately carb swaps come with some strings attached that seem to get glossed over in all the happy marketing for carbs. Sorry to be the bearer of bad news. Long term: watch the classifieds forum. Used 123 dizzy’s seem to pop up from time to time at more affordable pricing. |
930cabman |
Jun 27 2024, 01:35 PM
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#8
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Advanced Member Group: Members Posts: 3,523 Joined: 12-November 20 From: Buffalo Member No.: 24,877 Region Association: North East States |
I like my 009, considered a 123, but why?
I also like my Weber 40IDF twin carbs |
Spoke |
Jun 27 2024, 01:42 PM
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#9
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Jerry Group: Members Posts: 7,051 Joined: 29-October 04 From: Allentown, PA Member No.: 3,031 Region Association: None |
In the process of swapping the FI, on my 2.0L to Empi carbs. Care to elaborate on what is happening/not happening with the FI right now? As others mentioned, carbs can get you running fairly quickly but are not optimal w/o changing the cam and the dizzy. I have all the parts from a 2L FI system and would love to put them back on my 2056 although I do not know if the cam was changed. Plus my 911 is down with an engine R&R so I need to have one P-car running at all times. |
Superhawk996 |
Jun 27 2024, 01:42 PM
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#10
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914 Guru Group: Members Posts: 6,469 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch |
I like my 009, considered a 123, but why? I also like my Weber 40IDF twin carbs I had IDF’s and a 009 back in the day. Literally drove that rig for tens of thousands of miles before I had the 009 re-curved. Night and day difference. The ability to recurve the 123 via the app to whatever you want is a huge technology difference vs finding someone with the equipment (basically now obsolete) and proper springs and weights to recurve the 009 mechanically. |
JeffBowlsby |
Jun 27 2024, 01:51 PM
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#11
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914 Wiring Harnesses Group: Members Posts: 8,657 Joined: 7-January 03 From: San Ramon CA Member No.: 104 Region Association: None |
https://www.sparxwerks.com/ may be able to recurve the dizzy.
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Superhawk996 |
Jun 27 2024, 01:58 PM
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#12
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914 Guru Group: Members Posts: 6,469 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch |
I can’t vouch for the complete accuracy (not my data) but it captures the jist of the 009 flaws
Too much total advance and too soon in the RPM range. This causes you to dial back the timing at low rpm. Off the line it will bog (flat spot) then at some point things catch up between carb airflow and ignition and then it screams for a bit and then falls a bit flat near redline because it was dialed back initially to keep total advance around 27 -29 degrees. My carbed 1911 (with cam & raised CR) used to start to ping around 29-30 degrees. The 009 “worked” but was a compromise until re-curved Source: http://www.914world.com/bbs2/index.php?showtopic=275097 |
Osnabruck914 |
Jun 27 2024, 02:02 PM
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#13
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Member Group: Members Posts: 85 Joined: 19-December 22 From: United States Member No.: 27,038 Region Association: South East States |
DO NOT bother with a 009 (personal experience). I am running an SVDA dizzy with dual Dellortos, and it runs silky smooth. Not oversizing your main venturis is also a big thing in getting things right.
Osnabruck914 |
Shivers |
Jun 27 2024, 02:22 PM
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#14
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Senior Member Group: Members Posts: 2,654 Joined: 19-October 20 From: La Quinta, CA Member No.: 24,781 Region Association: Southern California |
I can’t vouch for the complete accuracy (not my data) but it captures the jist of the 009 flaws Too much total advance and too soon in the RPM range. This causes you to dial back the timing at low rpm. Off the line it will bog (flat spot) then at some point things catch up between carb airflow and ignition and then it screams for a bit and then falls a bit flat near redline because it was dialed back initially to keep total advance around 27 -29 degrees. My carbed 1911 (with cam & raised CR) used to start to ping around 29-30 degrees. The 009 “worked” but was a compromise until re-curved Source: http://www.914world.com/bbs2/index.php?showtopic=275097 Wow, that is exactly what mine does, 40’s and an 009. Not a big deal on a twisty, but yeah on the fwy it gets to a certain rpm and hits a wall. |
Superhawk996 |
Jun 27 2024, 02:38 PM
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#15
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914 Guru Group: Members Posts: 6,469 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch |
DO NOT bother with a 009 (personal experience). I am running an SVDA dizzy with dual Dellortos, and it runs silky smooth. Not oversizing your main venturis is also a big thing in getting things right. Osnabruck914 @osnabruck914 Details needed for OP. SVDA is a very generic term that could literally be any number of dizzys VW used since 74’ with various curves. Unfortunately the Aircooled.net SVDA is no longer available though them. Which one are you using? Are you ported off just one cylinder or are you using a vacuum box and/or check valves? |
Osnabruck914 |
Jun 27 2024, 03:43 PM
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#16
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Member Group: Members Posts: 85 Joined: 19-December 22 From: United States Member No.: 27,038 Region Association: South East States |
[/quote]
@osnabruck914 Details needed for OP. SVDA is a very generic term that could literally be any number of dizzys VW used since 74’ with various curves. Unfortunately the Aircooled.net SVDA is no longer available though them. Which one are you using? Are you ported off just one cylinder or are you using a vacuum box and/or check valves? [/quote] It is a Flamethrower SVDA dizzy. The vacuum is coming from a single port on the left carb and have an inline check valve. I tried T-ing two lines together from left and right carbs, but it was much smoother with a single source of vacuum. It's a 2.0 and I found 30mm main vents worked best on the DRLAs. Osnabruck914 |
930cabman |
Jun 27 2024, 04:04 PM
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#17
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Advanced Member Group: Members Posts: 3,523 Joined: 12-November 20 From: Buffalo Member No.: 24,877 Region Association: North East States |
In the process of swapping the FI, on my 2.0L to Empi carbs. Care to elaborate on what is happening/not happening with the FI right now? As others mentioned, carbs can get you running fairly quickly but are not optimal w/o changing the cam and the dizzy. I have all the parts from a 2L FI system and would love to put them back on my 2056 although I do not know if the cam was changed. Plus my 911 is down with an engine R&R so I need to have one P-car running at all times. How is the status with your 930? |
930cabman |
Jun 27 2024, 04:08 PM
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#18
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Advanced Member Group: Members Posts: 3,523 Joined: 12-November 20 From: Buffalo Member No.: 24,877 Region Association: North East States |
I can’t vouch for the complete accuracy (not my data) but it captures the jist of the 009 flaws Too much total advance and too soon in the RPM range. This causes you to dial back the timing at low rpm. Off the line it will bog (flat spot) then at some point things catch up between carb airflow and ignition and then it screams for a bit and then falls a bit flat near redline because it was dialed back initially to keep total advance around 27 -29 degrees. My carbed 1911 (with cam & raised CR) used to start to ping around 29-30 degrees. The 009 “worked” but was a compromise until re-curved Source: http://www.914world.com/bbs2/index.php?showtopic=275097 Wow, that is exactly what mine does, 40’s and an 009. Not a big deal on a twisty, but yeah on the fwy it gets to a certain rpm and hits a wall. My 2056 with Elgin cam, 009 and Weber 40 IDF's pull nicely to 6k in 1st, 2nd, 3rd and 4th gears I do not have any history with the 009 other than it was laying around and seems to work ok. Probably dumb luck |
brant |
Jun 27 2024, 04:09 PM
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#19
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914 Wizard Group: Members Posts: 11,726 Joined: 30-December 02 From: Colorado Member No.: 47 Region Association: Rocky Mountains |
I actually think the 009 is the worse distributor you can use
The 050 a little better I have a 1.8 distributor from a certain year (74?) That is a better one to use 123 is the best available right now |
Superhawk996 |
Jun 27 2024, 05:08 PM
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#20
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914 Guru Group: Members Posts: 6,469 Joined: 25-August 18 From: Woods of N. Idaho Member No.: 22,428 Region Association: Galt's Gulch |
My 2056 with Elgin cam, 009 and Weber 40 IDF's pull nicely to 6k in 1st, 2nd, 3rd and 4th gears I do not have any history with the 009 other than it was laying around and seems to work ok. Probably dumb luck When my 1.7 was totaled (not me driving) I sold off lots of parts at Hershey. Given you’re in Buffalo, maybe my re-curved 009 found its way into your hands (IMG:style_emoticons/default/piratenanner.gif) Wouldn’t that be something? I always wondered where all those parts ended up. (IMG:style_emoticons/default/idea.gif) |
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